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6 6 TITLE DEVELOPMENT OF EQUIPMENT FOR THE HEAT TREATMENT OF SMALL DIAMETER LIGHT WALL TITANIUM ALPHA BETA ALLOY TUBE CLUSTER USED AS ENERGY ABSORBER CHART no i22_ PMORITY J2L RELATED CAMR CHARTS MANUFACTURING REQUIREMENT E s t a b l i s h heat treatment equipment and techniques for honeycomb c l u s t e r of alpha beta a l l o y titanium tubes (1/4 Inch to 1/2 inch OD x 0 001 to 0 010 inch w a l l ) to obtain uniform compressive y i e l d strength and maximum p l a s t i c s t r a i n as measured at room temperature and at 1500F P l a s t i c s t r a i n energy absorption of 40 000 foot pounds/pound of c l u s t e r uniform mechanical p r o p e r t i e s l e s s than 10 percent v a r i a t i o n from 0 to 500F and l e s s than 20 percent v a r i a t i o n from minus 250F Co 1 00 F are key requirements The maximum temperature r e s u l t s from heating of the energy absorber gear while i t i s stowed in the s p a c e c r a f t compartment during entry before deployment or from engine exhaust heating Both could be lowered by design provisions but at the expense of added weight AARP REFERENCES E Cha >s. B Cha t . 319 148b 153a b PSFVPS Char ts . APPLICABLE PROCESS VACUUM AND CONTROLLED ATMOSPHERE HEAT TREATMENT Code 4 01 01 STATE OF THE ART ASSESSMENT Since T i 6 Al 4V and s i m i l a r a l l o y s w i l l be p r e c i p i t a t i o n strengthened in the neighborhood o£ 1200F p r o p e r t i e s at 1500F w i l l more c l o s e l y r e f l e c t those of a s o l i d s o l u t i o n than a p r e c i p i t a t i o n strengthened matrix but t h i s should not pose a serious problem On the other hand the requirement that maximum v a r i a t i o n i n mechanical p r o p e r t i e s s h a l l not exceed 20 percent from minus 250F to 1500F may be d i f f i c u l t to a t t a i n with the pre c i p i t a t i o n strengthened a l l o y s or for that matter any a l l o y known today A d e t e r i o r a t i o n in uniformity of p r o p e r t i e s can be expected at the point where the p r e c i p i t a t e begins to d i s s o l v e in the p r e c i p i t a t i o n strengthening systems but even for s o l i d s o l u t i o n type a l l o y s or i n f a c t d i s p e r s i o n strengthened a l l o y s t h i s requirement does not appear to be w i t h i n our grasp for the time period indicated Thus i t i s very l i k e l y that the designer w i l l have to provide s u f f i c i e n t thermal pro t e c t i o n to l i m i t the temperature range to assure p r o p e r t i e s within 20 percent of design or l e s s The alpha beta titanium a l l o y s respond to duplex type heat treatment i e they may l e r a p i d l y cooled from the s o l u t i o n temperature and subsequently age hardened g e n e r a l l y i n the temperature range 900F to 1200F and for times between 8 and 24 hours to obtain optimum properties Delaying the quench from the s o l u t i o n temperature r e s u l t s in widely d i f f e r e n t t e n s i l e p r o p e r t i e s depending on the length of the lelay Because titanium a l l o y i s a r e a c t i v e m a t e r i a l i t must be heat treated i n a vacuum or with i n e r t gas atmosphere such as argon While vacuum i s preferred i t i s d i f f i c u l t to cool r a p i d l y (quench) in a vacuum As a r e s u l t optim m properties may not be achieved using t h i s type of furnace With an argon p r o t e c t i v e atmosphere Che m a t e r i a l may be withdrawn from a hot zone and r a p i d l y quenched in water or some other l i q u i d medium For many m i l l shapes and forms Chis technique i s acceptable p a r t i c u l a r l y i f s l i g h t contamination or d i s c o l o r a t i o n i s not objectionable For Che m a t e r i a l under con s i d e r a t i o n i e small diameter l i g h t w a l l (1/4 inch to 1/2 inch OD X 0 001 inch w a l l ) alpha beta titanium a l l o y tubing f a b r i c a t e d into honeycomb c l u s t e r s Continued on next page ALTERNATE PROCESSES NONE Code
6 7 CHART N O In STATE OF THE ART ASSESSMENTS, continued such d r a s t i c l i q u i d quenching may c r e a t e e x c e s s i v e d i s t o r t i o n and contamination which cannot be t o l e r a t e d T h i s i s p a r t i c u l a r l y true for tubing having a w a l l t h i c k n e s s i n the range of 0 001 inch to 0 003 inch The use of large volumes of pre cooled argon to achieve the required c o o l i n g r a t e without damage may be f e a s i b l e for the a l l o y i n question A completely s a t i s f a c t o r y heat t r e a t i n g technique for these l i g h t w a l l s i s not a v a i l a b l e and i t i s l i k e l y that usage or demand w i l l not adequately advance the s t a t e of the a r t to the designated time period A c t u a l l y no process now e x i s t s to produce 1/4 inch OD x 0 001 inch w a l l tubing, Conse quently development of heat t r e a t techniques w i l l have to u t i l i z e mock up c l u s t e r s perhaps with tubing made from welded f o i l Another important unknown i s the e f f e c t of s e c t i o n s i z e on mechanical p r o p e r t i e s and heat t r e a t response Most data a v a i l a b l e today are based on normal s e c t i o n s i z e s say l / ) 6 inch or t h i c k e r I t i s a recognized f a c t that as th i c k n e s s f a l l s below 0 015 inch, t h i s response f a c t o r cannot be ignored Because of these unknown f a c t o r s a rather v e r s a t i l e furnace embracing c o n t r o l l e d heating r a t e s c o n t r o l l e d cooling r a t e s c o n t r o l l e d atmosphere (vacuum or i n e r t gases) and s p e c i a l handling techniques would be required CRITICAL PROBLEMS 1 M a t e r i a l s are not a v a i l a b l e which w i l l show a maximum of 20 percent v a r i a t i o n i n mechanical p r o p e r t i e s from minus 250 F to 1500 F 2 C o n t r o l l e d heating and cooling r a t e s are re q u i r e d to provide the necessary p r o p e r t i e s for p l a s t i c s t r a i n energy absorption at room temperature and at 1500 F 3 Heat t r e a t response of extremely l i g h t s e c t i o n s 0 001 inch to 0 010 inch w a l l t h i c k n e s s i s an unknown fa c t o r 4 Handling of a c l u s t e r of tubes during and a f t e r heat treatment to avoid mechanical damage presents s e r i o u s m a t e r i a l s handling problems 5 A s a t i s f a c t o r y process i s not known for handling a c l u s t e r of tubes ( j o i n e d together by by weldinx or brazmn) to obtain proper heat t r e a t response PROPOSED DEVELOPMENT PROGRAM OBJECTIVE E s t a b l i s h procedures for h at t r e a t i n g small diameter l i g h t w a l l (1/4 inch UD to 1/2 inch OD X 0 001 inch to 0 010 inch w a l l ) titanium tubes of alpha beta a l l o y (such as T i 6 Al 4V) f a b r i c a t e d into a crushable honeycomb c l i s t e r 6 inches to 10 inches diameter and approximately 7 inches to 3 feet long I t i s important that the tubes and c l u s t e r s have uniform compressive y i e l d strength and maximum p l a s t i c s t r a i n C a r e f u l l y c o n t r o l l e d heat treatment w i l l be necessary to achieve these properties BACKGROUND Because titanium a l l o y s are r e a c t i v e to oxygen and nitrogen c l u s t e r s of such t h i n a l l tubes must e i t h e r be heat treated in a vacuum or under a high p u r i t y i n e r t gas such as argon i n order to prevent damage or d e s t r u c t i o n In a d d i t i o n heat t r e a t i n g c y c l e s may be complex r e q u i r i n g c o n t r o l l a b l e heating and cooling r a t e s T h i s I S c h a r a c t e r i s t i c not only of the alpha beta titanium a l l o y mentioned but of any p r e c i p i t a t i o n strengthening system or metastable systems which depend on p r e c i p i t a t i o n and transformation for f i n a l p r o p e r t i e s I t i s probable that when f i n a l l y developed the a l l o y for t h i s a p p l i c a t i o n w i l l depend on more complex metallurgy (and thus heat treatment) than those c u r r e n t l y known APPROACH To provide for heat treatment of such a h y p o t h e t i c a l a l l o y a h i g h l y v e r s a t i l e furnace should be developed as follows 1 Design and f a b r i c a t e a vacuum furnace capable of providing c o n t r o l l a b l e heating dwell and cooling c y c l e s the l a t t e r being on the order of 750 F per second Continued on next page
- 6 8 - APPROACH. continued CHART N O in 2 The design s h a l l permit the use of a noble p r o t e c t i v e atmosphere such as argon i n the event vacuum cannot be u t i l i z e d 3 In a d d i t i o n the vacuum r e t o r t s h a l l be designed i n such a manner that large volumes of pre cooled argon (or other noble gases) can be introduced at the appropriate moment to obtain the required cooling r a t e 4 The furnace s h a l l be designed to handle at l e a s t 100 Ibs/hr of work and p r e f e r a b l y 200 Ibs/hr without mechanical damage or d i s t o r t i o n to the extremely f r a g i l e tubing 5 Design and f a b r i c a t e f i x t u r e s to support the c l u s t e r s of f r a g i l e tubing during the heat treatment c y c l e INSPECTION TECHNIQUES SUPPLEMENT RECOMMENDATIONS The i n s p e c t i o n recommendations given in CAMR 115 are a p p l i c a b l e here and are incorporated by reference
69 PRIORITY RATING WORKSHEET CHART P R 0 6 R A M F A C T O R S P R O f l R A M P R O B A B I L I T Y O F S U C C E S S ⢠L O W Z ^ M O D E R A T E 5 ⢠mei» 8 C R I T I C A L P R O B L E M S TO B E S O L V E D D F C N V / N O T TOO D I F F I C U L T Z "ft S O M E / D I F F I C U L T S a M A N Y / V E R Y D I F F I C U L T S P R O C E S S C R O W T H P O T E N T I A L )K L I T T L E OR U N D E F I N A D L E O a K E ^ O f i N l l A B L E p o r e M T I A L 4 A P P L I C A T I O N S O T H E R T H A N AIR F O R C E ⢠NONE O S O M E 4 M A N Y e N E C E S S I T Y F O R AIR F O R C E F U N / O I N Q ⢠L O W HlfiH I N D U S m / O T H E f t S o u r E F F tX 4 Q MootiiATE - SDMI BTtotx oTHce. â¢souenes e X E i££H ISWE Ailt foUet F u M P M a L I K C L V l i NEED FACTORS S Y S T E M S P R O B A B I L I T Y H i a H F > s o B A B i i r y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T l O A L I T Y V E R Y H K T H M I & H F A I R L O W F R F a U E N C Y OF R E Q U I R E M E N T IN S Y S T E M M A R E T H A N 3 C0I^PeHtK13 7. 3 C « M p e N E i u r s S I N f l L E C o M P e N E N T D e 9 l S N A L T E R M A T E S No A L T E R N A T E F O a E e C E N ONE A L T E R N A T E S E V E C . A L A L T E E W A T E « M A T E R I A L S I M P L I C A T I O N NEW M A r e d i O L peytLof>MtNT e e a o IVWrCBlflL I M P f t O V t M C N T R E S ! P NO P R O B L E M F o n e s c e v i \t 8 4 vt 3 3 2 I â¢3 6 3 6 4 o CALCULATE PRIORITY S T E P I S T E P 2 1^ RAW SCORES FOR EACH I^EFEKEIKXP COMPONENT IN T A B L E S AT L N D OF P A N E L T J t P O t T W I T H VlAlO T O T \ L S E N T t R C P fN q u M X f l t V AT e i S H T AARP RANM SCoUCS S V S r e M S ⢠⢠I CIRCLE MIGHCST A A R P RAW S C O R E n- IN rACH CITHER S Y S T E M C I R C L E NEXT M I G H E S T ^ 9 IF WITHIN N U M S E R OF 4 F ^ I W T S O F T O P / S C O R E L O W L S T E P 3 C I R C L E F R E O O E N C Y DISTRIBUTION F A C T O R riicri 3 O R Moce S C O R E B £ L O W ( I 2. N U M B E R O F S Y S T E M S L O W 0 I 2 n. Meet 1 0 1 a 1 4 1 3 1 *f 1 z 1 *f 1 «f 2? -379 P = nx f = T O T A L = 2& 3Z PRIORITY -ff ®
70- TITLE OF LARGE COMPLEX CLOSE TOLERANCE NICKEL BASE AND COBALT BASE SUPERALLOY AIRFRAME COMPONENTS CHART NO PRIORITY 111- R E U T E D CAMR CHARTS MANUFACTURING REQUIREMENT P r e c i p i t a t i o n strengthened and d i s p e r s i o n strengthened n i c k e l base s u p e r a l l o y a i r f r a m e components are r e q u i r e d f o r use up t o 2000 F F i t t i n g s up t o 48 Inches are used i n b u i l t up assemblies f o r hypersonic v e h i c l e bulkheads frames and tr u s s e s T h r u s t v e c t o r c o n t r o l / d e f l e c t o r vanes having w a l l t h i c k n e s s o f 0 050 Inches up t o 36 Inches span 2A inches cord w i d t h and 5 Inches deep are r e q u i r e d f o r VTOL a i r c r a f t P a r t s cast from these a l l o y s are r e q u i r e d t o have mechanical p r o p e r t i e s o f y i e l d s t r e n g t h / d e n s i t y r a t i o o f 100 000 Inches a t 2000 F The expected s t r e s s r u p t u r e p r o p e r t i e s are 20 000 p s l f o r 30 minutes at 2000 F d u r i n g each thermal c y c l e The p a r t s are expected t o be s u i t a b l e f o r c a s t i n g t o c l o s e t o l e r a n c e s During o p e r a t i o n the p a r t s would be su b j e c t e d to thermal and f a t i g u e c y c l i n g under con d i t i o n s of h i g h l o a d i n g AARP REFERENCES E Cho t s . B Charts. 10 47 80 31b A2b PSFVPS Char ts . APPLICABLE PROCESS INDUCTION MELTING AND VACUUM CASTING INTO INVESTMENT OR CERAMIC MOLDS Code 1 02 08 1 02 09 STATE OF THE ART ASSESSMENT I n c o n s i d e r i n g the s t a t e of the a r t f o r c a s t i n g d i s p e r s i o n strengthened and p r e c i p i t a t i o n strengthened s u p e r a l l o y compositions the two are t r e a t e d s e p a r a t e l y due t o the d i f f e r e n c e s i n s t a t e of knowledge as i t r e l a t e s t o c a s t i n g these a l l o y types F i r s t a t t e n t i o n i s g i v e n t o the problems a s s o c i a t e d w i t h c a s t i n g the d i s p e r s i o n type a l l o y s We consider here the I n s o l u b l e d l s p e r s o l d s The c r i t i c a l d i s p e r s i o n cannot be achieved f o r these d i s p e r s i o n strengthened a l l o y s i n cast form The s t a t e o f the a r t I n c a s t i n g these m a t e r i a l s i n t o i n t r i c a t e shapes i s ex t r e m e l y l i m i t e d i f i t e x i s t s a t a l l I n any event no c a s t i n g s have been made s u c c e s s f u l l y w i t h these a l l o y types Th i s should not and does not r u l e out the p o s s i b i l i t y o f ever producing c a s t i n g s from these a l l o y s I t does however r a i s e s e r i o u s doubts as t o whether the goals can be met i n the time p e r i o d o f I n t e r e s t Since no ca n d i d a t e a l l o y c o mpositions are known t o e x i s t these d i s p e r s i o n type a l l o y s are removed from c o n s i d e r a t i o n The g r e a t e s t s t r i d e s have been made i n c a s t i n g p r e c i p i t a t i o n s t r e n g t h e n e d s u p e r a l l o y components f o r p r o p u l s i o n a p p l i c a t i o n s The progress I n t h i s area i s best I l l u s t r a t e d by the success achieved i n c a s t i n g t u r b i n e buckets and blades These shapes have been s u c c e s s f u l l y cd becau o f r e p r o d u c i b i l i t y i n g r a i n s i z e c o n t r o l c o n t r o l l e d d i r e c t i o n a l s o l i d i f i c a t i o n i n t r i c a t e l y cored h o l l o w blades t o g e t h e r w i t h a h i g h degree o f dimensional p r e c i s i o n P r e c i p i t a t i o n strengthened n i c k e l base and c o b a l t base s u p e r a l l o y c a s t i n g s weighing up to 40 pounds have been made by investment c a s t i n g techniques Semi permanent ceramic molds can be used to produce c a s t i n g s as l a r g e as 200 pounds w i t h w a l l t h i c k n e s s e s o f 0 100 inches To overcome d i f f i c u l t i e s encountered i n producing l a r g e r c a s t i n g s i t w i l l be necessary to e f f e c t i v e l y combine the t e c h n o l o g i e s i n v o l v e d i n p r o d u c t i o n of l a r g e p r e c i s i o n h i g h q a l i t y s t e e l c a s t i n g s and the c o n c u r r e n t manufacture o f sma l l Investment c a s t s u p e r a l l o y components of e q u a l l y h i g h r e l i a b i l i t y The present d i f f i c u l t i e s r e q u i r e a compromise between o b t a i n i n g good f l o w and low p o r o s i t y I n order t o achieve these a l a r g e amount of superheat IS r e q u i r e d which r e s u l t s i n increased g r a i n s i z e i n the f i n i s h e d c a s t i n g Molds are u s u a l l y heated o u t s i d e the vacuum and then placed i n s i d e the chamber O f t e n o u t g a s s i n g problems Continued on next page ALTERNATE PROCESSES FORGING MACHINING Code 2 01 00 5 01 00
71 STATE OF THE ART ASSESSMENT, c o n t i n u e d CHART NO J.IZ develop when a heat i s poured i n vacuum Post aging t r e a t m e n t s are used to improve s t r e n g t h and t o improve s t r e s s r u p t u r e p r o p e r t i e s A number of s u p e r a l l o y compositions are being used t o cas t components f o r aerospace v e h i c l e s I n a d d i t i o n some development programs are being conducted t o improve the c a s t a b i l i t y o f some o f the e x i s t i n g s u p e r a l l o y compositions Of those s u p e r a l l o y s s u i t a b l e as c a s t i n g a l l o y s the most commonly used ones are INCO 713C INCO 713LC GMR 235 UDIMET 500 HS 31 H a s t e l l o y X PDia 162 and 163 INCO 718 Rene 41 and X40 CRITICAL PROBLEMS 1 The s u p e r a l l o y c o m p o s i t i o n s do not meet the r e q u i r e d s t r e n g t h l e v e l s as s t a t e d Many o f the c a s t i n g a l l o y s have not been e v a l u a t e d a t temperatures above 1800 F Most of these have been s t u d i e d o n l y up t o temperatures o f 1500 F t o 1600 F Even a t these temperatures i t i s obvious t h a t the pre s e n t c a s t i n g a l l o y s do not meet the r u p t u r e l i f e o f 10 hours a t 1800 F H a s t e l l o y X has a r u p t u r e l i f e o f 10 hours a t 1800 F however the s t r e n g t h i s decreased t o 6000 p s l 2 Semi permanent and permanent molds are not a v a i l a b l e t o c a s t these a l l o y c o m p o s i t i o n s i n l a r g e s i z e s Mold r e a c t i o n causes s u r f a c e d e f e c t s such as shr i n k a g e v o i d s and p o r o s i t y The requi r e m e n t s f o r accuracy and p r e c i s i o n o f c o n f i g u r a t i o n cannot be met w i t h c o n v e n t i o n a l c o a t i n g techniques Only through methods such as ceramic s h e l l molding massive investment molding w i t h permanent or d i s p o s a b l e p a t t e r n s or thr o u g h use of permanent mold processes can the r e q u i r e d l e v e l s be approached 3 The waxes used i n investment processes l a c k s t r e n g t h and as such cannot support the l a r g e r s i z e c a s t i n g s 4 C o n t r o l o f g r a i n s i z e must be accomplished w i t h o u t a d v e r s e l y a f f e c t i n g f l u i d i t y or i n c r e a s i n g the p o s s i b i l i t y of d e f e c t s such as mi c r o s h r i n k a g e 5 Vacuum p r o c e s s i n g m e l t i n g and c a s t i n g i s c o s t l y and time consuming Improvements are needed t o handle l a r g e r m e l t s and a t the same time be able t o produce q u a l i t y c a s t i n g s which meet s t a t e d r equirements PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop l a r g e complex c l o s e t o l e r a n c e n i c k e l base and c o b a l t base a l l o y a i r f r a m e c a s t i n g s f o r h i g h temperature s e r v i c e BACKGROUND Ca s t i n g development should c o n c e n t r a t e on p r e c i p i t a t i o n s t engthened n i c k e l base a l l o y s s e l e c t i n g c ompositions o f f e r i n g the best c o m b i n a t i o n of p r o p e r t i e s f o r c a s t i n g i n t r i c a t e l a r g e t h i n - w a l l e d s e c t i o n s (such as f l o w shrinkage s e g r e g a t i o n ) and s e r v i c e p r o p e r t i e s (such as e l e v a t e d temperature s t r e n g t h o x i d a t i o n r e s i s t a n c e e t c ) The a l l o y s e l e c t i o n phase may p o i n t up a need f o r new co m p o s i t i o n s f o r reasons o t h e r than i n a b i l i t y o f pre s e n t a l l o y s t o meet AARP p r o p e r t y g o a l s No ma n u f a c t u r i n g development f o r d i s p e r s i o n strengthened n i c k e l base a l l o y s can be o u t l i n e d a t t h i s time A l l o y development i s encouraged t o seek co m p o s i t i o n s which r e t a i n the c h a r a c t e r i s t i c o f c r i t i c a l d i s p e r s i o n o f p a r t i c l e s d u r i n g c a s t i n g C a s t i n g o f c o b a l t a l l o y s would b e n e f i t from development o f c a s t i n g techniques f o r p r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base a l l o y s and do not r e q u i r e separate f u n d i n g APPROACH 1 A mold m a t e r i a l and mold d e s i g n program should be i n i t i a t e d Mold pressed ceramics should be i n v e s t i g a t e d t o achieve c l o s e r mold t o l e r a n c e s Mold designs should be researched t o e s t a b l i s h optimum heat f l o w c o n t r o l Mold designs m a t e r i a l s and heat t r e a t m e n t s should be s t u d i e d t o reduce c a s t i n g warpage improve mold s t r e n g t h reduce mold shrinkage and mold c o n t a m i n a t i o n and p o s s i b l y reduce m i c r o p o r o s i t y Mold c o a t i n g s should be i n v e s t i g a t e d which produce a c a s t i n g s u r f a c e t h a t i s s u i t a b l e f o r the a p p l i c a t i o n o f o x i d a t i o n r e s i s t a n t c o a t i n g s Three p r o m i s i n g Continued on next page
7 2 CHART , . _ N O / / y PROPOSED DEVELOPMENT PROGRAM, c o n t i n u e d APPROACH, cont d mold m a t e i l a l types should be developed u s i n g subscale and f u l l s c a l e mold desig n s 2 An Investment wax program should be undertaken t o s t r e n g t h e n the wax t o make p o s s i b l e l a r g e r i n t r i c a t e c a s t i n g s 3 I n j e c t i o n molded cores which can be leached w i t h h o t c a u s t i c should a l s o be s t u d i e d E x p e r i m e n t a l f u l l s i z e c a s t i n g s should be u t i l i z e d h A program should be i n i t i a t e d t o develop p r e s s u r e p o u r i n g t e c h n i q u e s t o reduce d e f e c t s and t o improve the f l o w o f m e t a l i n t o the mold 5 Research should i n c l u d e methods t o e c o n o m i c a l l y r e use scraps from p r e v i o u s m e l t i n g The program c o u l d b e g i n w i t h more s i m p l e a l l o y systems 6 The d i r e c t i o n a l s o l i d i f i c a t i o n program should be expanded t o s t u d y t h e e f f e c t s o f the d i f f e r e n t t h e r m a l b l a n k e t m a t e r i a l s on s o l i d i f i c a t i o n b e h a v i o r 7 A f u r n a c e improvement program s h o u l d be sponsored t o a Speed up c y c l i n g m a t e r i a l i n t o and o u t of the f u r n a c e by d e v i c e s such as o u t e r chambers and l a z y susan type d e v i c e s b P r o v i d e f o r mold p r e h e a t i n g w i t h i n the vacuum chamber c P r o v i d e f o r Improved vacuum by i n c l u d i n g such t h i n g s as a degassing o u t e r chamber f o r a l l m a t e r i a l s and p a r t s t h a t go i n t o the m e l t i n g system d Assure s u f f i c i e n t p r o d u c t i o n c a p a c i t y 8 As new and advanced a l l o y s are developed or the use o f e x i s t i n g a l l o y s extended t o more c o m p l i c a t e d c a s t i n g s the development programs must I n c l u d e c o n s i d e r a t i o n of Che weld r e p a i r problems t h a t are i n t r o d u c e d t o g e t h e r w i t h the development o f adequate means t o i n s p e c t and a p p r a i s e r e p a i r welds 9 Heat t r e a t m e n t procedures f o r c a s t i n g s t o develop d e s i r e d p r o p e r t i e s t h r o u g h o u t t h i c k and t h i n s e c t i o n s f o r l a r g e p a r t s should be e s t a b l i s h e d 10 P r o t o t y p e component c o a t i n g s should be e v a l u a t e d by ground t e s t i n g under s i m u l a t e d v e h i c l e e n v i r o n m e n t a l c o n d i t i o n s c o r r e s p o n d i n g t o those i n d i c a t e d by AARP
73 PRIORITY RATING WORKSHEET C H A R T PROfiRAM CRITICAL PROCESS ⢠A P P L I C A T I O N S a a X NECESSITY PROBABIL ITY OF S U C C E S S D LOW MOOERATe ⢠HIAH P R O B L E M S T O B E S O L V E D ⢠FEVV/NOT TOO PIFFltfUUT S O M E / D I F F I C U L T ⢠M A N Y / V E R Y D I F F I C U L T G R O W T H P O T E N T I A L L I T T L E O R U N D E F I N A B L E eeco&HMBie P O T E M T I A L O T H E R T H A N A I R F O R C E N O N E S O M E M A N Y FOR AIR Z 5 8 Z 3 e o 4 o 4 6 F O R C E FUNDIWa LOW HI6« IMtUSTItV/cTH A 6 0 V r C F F I T ^ M OeHATE - SCMC 6Fro«.T OTHoe 'SOUC'ieS 8 e x £ U i s i y c A I R F O A C L F U M P N 6 L I K C L V vl. p a N E E D F A C T O R S SYSTEMS PROBABILITY HI<3H PKOBABIL lTY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y - COMPONENT C R I T l C A L I T Y VeRV Hl£-H H I < S H FAIR L o w FREauENCY OF REQUIREMENT I N S Y S T E M MOBC THAN 3 COMPaNEMTS Z 3 C«MPl>lUENr^ S l w a L E <20MPeNENT D E S I S N A L T E R M A T E S No ALTERNATe R i a E S E E N ONE ALTERNATe S E V E R A L . A L T E R M A T E S M A T E R I A L S IMPLICATION NEW MATERIAL P£Vtli)(>M£»IT B e * O IVWTCRlAL IMPrtOVtMENT RES) P NO PROBLEM F o R e ^ c e u 12 8 4 IZ -9 & 3 3 2 I â¢3 6 3 £ 4 o CALCULATE S T E P I S T E P 2 P R I O R I T Y RAW S C O R E S F O R EACH REFceENrtP cof/ivonctn I H TABLES AT tlXD or P A N E L IZtPOtT W I T H T S A W Tar \LS E N T E K E P IM <3UlUMAItV AT gtSMT S V S T E M S A A R P RAVJ SCORES (^ti I r ~ ⢠⢠⢠⢠⢠⢠⢠⢠⢠n -CIRCLE HIGHEST A A R P RAW S C O R E IN EACH CffHER S Y S T C M C I R C L E NEXT H I G H E S T IF WITHIN 4 P O I M T S O F T O P S C O R E n ^ LOW ^ 30 S C O R E NUM&ER OF â¢SysTElWS H l^H STEP 3 CIRCLE FREOUENCY DISTRIBUTION FACTOR f BEUJWt MUMoetL O F sysrtMS I 2. Hicrt 3 O R M O C E NUM&ER OF S Y S T E M S LOW 0 1 2 B. Most 1 0 1 a 1 1 1 3 1 z 1 *f 1 4 TOTAL PRIORITY
74 TITLE COMPLEX THIN WALL REFRACTORY METAL CASTINGS CHART N O PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Columbium and molybdenum a l l o y s are r e q u i r e d i n complex c a s t i n g s up t o 48 Inches (5 50 l b s ) Minimum w a l l r e q u i r e m e n t s are 0 040 i n c h + 0 010 i n c h Y i e l d s t r e n g t h / d e n s i t y must be 100 000 inche s a t 2700 F and 150 000 inche s a t 2500 F S t r e s s r u p t u r e s t r e n g t h must be 20 000 p s i f o r 5 hours a t 2500 F The c a s t p a r t s must be J o l n a b l e and r e s i s t a n t t o d i s t o r t l o n f r o m t h e r m a l g r a d i e n t s The c a s t i n g s must be c o m p a t i b l e w i t h o x i d a t i o n r e s i s t a n t ceramic o x i d e coacinge Complex c a s t i n g s are r e q u i r e d f o r i n t e r n a l bulkheads frames s t i f f e n e r s t r u s s members f i t t i n g s and s t r u c t u r a l assemblies AARP REFERENCES E Chnrt . ^6 80 B Chart , 31a 42a P4FVPS Charts APPLICABLE PROCESS Code VACUUM ARC SKULL MELTING AND CASTING INTO GRAPHITE MOLDS 1 01 12 STATE OF THE ART ASSESSMENT Columbium A l l o y s U e l d a b l e h i g h s t r e n g t h columbium a l l o y s w i t h a d d i t i o n a l a l l o y elements such as U Zr C Hf T i and Mo are p r o d u c i b l e today w i t h y i e l d s t r e n g t h / d e n s i t y r a t i o s o f a p p r o x i m a t e l y 35 000 t o 75 000 inches a t 2500 F S t r e s s r u p t u r e l i m i t s are around 18 000 p s i a t 2400 F f o r 5 hours O x i d a t i o n r e s i s t a n t c o a t i n g s have been u n s u c c e s s f u l t o date due t o p i n h o l e type uncoated areas Only i n g o t s and b a s i c shapes have been c a s t No work has been done t o produce i n t r i c a t e w a l l s e c t i o n s S t r e n g t h p r o p e r t i e s i n the c a s t I n g o t s and shapes have been lower t h a n p u b l i s h e d v a l u e s Cold g r a p h i t e molds have been used These molds make g a t i n g d i f f i c u l t and s u r f a c e c a r b i d e f o r m a t i o n p r e v e n t s c l o s e c o n t r o l o f t o l e r a n c e s i n c a s t i n g s Arc s k u l l m e l t i n g i s necessary t o av o i d u n d e s i r a b l e c r u c i b l e c o n t a m i n a t i o n o f the m e l t S k u l l l o s s e s have been h i g h due t o i n s u f f i c i e n t power s i n c e p r e s e n t m e l t i n g p r a c t i c e uses a v a i l a b l e t i t a n i u m m e l t i n g t y p e equipment Vapors o f lower m e l t i n g c o n s t i t u e n t s i n t e r f e r e w i t h a r c s t a b i l i t y The pre s e n t m e l t i n g and c a s t i n g equipment can produce 24 i n c h s i z e s i n the 5 50 pound c l a s s Molybdenum A l l o y s Molybdenum a l l o y w i t h T i Zr and C has a t 2400 F S t r e s s r u p t u r e s t r e n g t h a t 2000 F i s being made f o r c o a t i n g molybdenum f o r o x l d a problem i s i n e l i m i n a t i n g b r l t t l e n e s s I n g o t s i n c r e a s e s but s i n c e complex c a s t s t r u c t u r e s ca columbium molybdenum has been l i m i t e d t o ingo have been used S k u l l m e l t i n g i s necessary t o los s e s are h i g h due t o l i m i t e d power on t i t a n i a l l o y c o n s t i t u e n t s make a r c s t a b i l i t y d i f f i c u l 24 i n c h s i z e s i n the 5 50 pound c l a s s a y i e l d s t r e n g t h / d e n s i t y r a t i o o f 108 000 Inches I S about 30 000 p s i f o r 100 hours Good p r o g r e s s t l o n p r o t e c t i o n u s i n g s l l l c l d e s A s e r i o u s can be worked t o reduce g r a i n s i z e and d u c t i l i t y nnot be worked b r i t t l e p a r t s r e s u l t . L i k e t or crude shape c a s t i n g s Cold g r a p h i t e molds p r e v e n t c o n t a m i n a t i o n f r o m t h e c r u c i b l e S k u l l urn m e l t i n g equipment Vapors o f lower m e l t i n g t P r e s e n t m e l t i n g equipment can produce Continued on n e x t page ALTERNATE PROCESSES FORCINGS EXTRUSIONS POWDER METALLURGICAL PROCESSES Code 2 01 00 2 03 00 1 03 00
7 5 CHART N O _ CRITICAL PROBLEMS Numeroi s and d i f f i c u l t problems must be solved t o meet the 1970 1985 r e q u i r e m e n t s C e n e r a l l y these problems are common t o c a s t i n g both columbium and molybdenum a l l o y s I uc are somewhat m a g n i f i e d f o r the l a t t e r a l l o y s because o f the h i g h e r m e l t i n g temperature:. 1 S t r e n g t h p r o p e r t i e s o f a v a i l a b l e a l l o y s are f a r below the r e q u i r e d s t r e n g t h level's 2 S u b s t a n t i a l work must be performed t o p r o v i d e c o a t i n g s w i t h adequate o x i d a t i o n r e s i s t a n c e 3 Mold m a t e r i a l s are not adequate f o r a c h i e v i n g a c c e p t a b l e s u r f a c e f i n i s h e s and c l o s e c o n t r o l o f t o l e r a n c e s , f o r p r e v e n t i n g r e a c t i o n s w i t h and c o n t a m i n a t i o n o f the r e f r a c t o r y c o a t i n g s and f o r p r e v e n t i n g r a p i d u n c o n t r o l l e d c o o l i n g and s o l i d i f i c a t i o n 4 C o n t r o l o f m e l t and p o u r i n g temperatures are s i z a b l e problems f o r c o n t r o l l i n g f l u i d i t y t o p r o v i d e adequate f e e d i n g o f complex shapes The usual r e q u i r e m e n t s e x i s t f o r l i m i t i n g d e n d r i t i c g r a i n s i z e and s e g r e g a t i o n and these problems are i n t e n s i f i e d because of the v e r y h i g h temperatures t h a t are i n v o l v e d D i r e c t i o n a l s o l i d i f i c a t i o n i s needed to minimize these problems 5 A s i g n i f i c a n t s c a l e up o f e l e c t r i c a l power i s needed f o r the i n c r e a s e d m e l t s i z e s s p e c i a l a t t e n t i o n needs t o be devoted t o i m p r o v i n g arc s t a b i l i t y and f o r p r e v e n t i n g adverse r e a c t i o n s o f a l l o y vapors i n r e d u c i n g arc s t a b i l i t y 6 I n t e g r a l furnace and m u l t i p l e c a s t i n g equipment must be p r o v i d e d so t h a t an adequate p r o d u c t i o n c a p a c i t y can be achieved which i s reasonably economic 7 Repair w e l d i n g t e c h n i q u e s do n o t e x i s t f o r a p p l i c a t i o n t o r e f r a c t o r y m e t a l c a s t i n g s 8 F i n a l l y e s p e c i a l l y d i f f i c u l t problems a r i s e because o f the n e c e s s i t y f o r p r e v e n t i n g e x c e s s i v e c o n t a m i n a t i o n o f c a s t i n g s from p i c k u p of gaseous i n t e r s t i t i a l c o ntaminants which are so d e t r i m e n t a l t o c a s t i n g d u c t i l i t y PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop the c a p a b i l i t y t o c a s t columbium and molybdenum a l l o y c a s t i n g t o c l o s e t o l e r a n c e s C a s t i n g s are i n t e n d e d as l i f t and c o n t r o l s t r u c t u r e s and r i g i d sub s t r u c t u r e s t h a t are exposed t o e l e v a t e d temperatures BACKGROUND Columbium A l l o y s A v a i l a b l e columbium a l l o y s do n o t have s u f f i c i e n t s t r e n g t h t o meet the r e q u i r e m e n t s Columbium a l l o y c a s t i n g s i n s i m p l e shapes can be case i n the s i z e s and w e i g h t r e q u i r e d i n the time p e r i o d I t i s emphasized however t h a t these are simple shapes A major developmental program w i l l be r e q u i r e d t o p r o v i d e the technology necessary t o produce complex columbium c a s t i n g s i n the 1970 1985 time p e r i o d Furnace power w i l l have t o be i n c r e a s e d i n order t o s c a l e up t o l a r g e r m e l t i n g c a p a b i l i t i e s Companion programs i n c o a t i n g s development w i l l be r e q u i r e d t o develop c o a t i n g s capable o f p r o t e c t i n g the s t r u c t u r e s a t h i g h tempera t u r e s Molybdenum A l l o y s The s i z e and w e i g h t r e q u i r e m e n t s f o r molybdenum c a s t i n g s can be met w i t h the p r e s e n t t e c h n o l o g y The f u r n a c e and s u p p o r t i n g equipment r e q u i r e d f o r columbium technology w i l l s u f f i c e f o r molybdenum An a l l o y such as Mo 1 25Ti 0 3Zr 0 15C appears t o be a l i k e l y c a n d i d a t e f o r meeting the s t r e n g t h r e q u i r e m e n t s As w i t h columbium a l l o y s a major development program must be conducted i n c r i e r to e s t a b l i s h an adequate molybdenum c a s t i n g t e c h n o l o g y However i t w i l l not be necessary t o c a r r y o u t complete development programs f o r each a l l o y system r a t h e r a basic r e f r a c t o r y m e t a l s c a s t i n g program i s i n d i c a t e d w i t h a d d i t i o n a l tasks designed t o s o l v e s p e c i a l problems a s s o c i a t e d w i t h i n d i v i d u a l a l l o y s ] S u i t a b l e c o a t i n g s t o p r o t e c t the s t r u c t u r e s from o x i d a t i o n are n o t a v a i l a b l e and need t o be developed The a l l o y s themselves tend t o be b r i t t l e when r e c r y s t a l l i z e d and are j o i n e d o n l y w i t h d i f f i c u l t y Some s m a l l amount o f TIG and MIG w e l d i n g i s p o s s i b l e however welds tend t o be b r i t t l e These a l l o y s w i l l p r o b a b l y lend themselves t o j o i n i n g by b r a z i n g and s o l d e r i n g Continued on next page
CHART 76 PROPOSED DEVELOPMENT PROGRAM, c o n t i n u e d APPROACH 1 A development program I s needed t o improve the s t r e n g t h c a p a c i t i e s o f colurabium and molybdenum a l l o y s i n the 2500 3400F temperature range Development o f c o a t i n g s w i t h improved o x i d a t i o n r e s i s t a n c e i s an a d d i t i o n a l r e q u i s i t e 2 A f u r n a c e improvement program i s needed t o p r o v i d e i n c r e a s e d e l e c t r i c a l power and t o reduce s k u l l losses F e a t u r e s should be i n c l u d e d f o r complete m o n i t o r i n g and c o n t r o l o f a l l t e m p e r a t u r e s C o n t r o l l e d h e a t i n g and c o o l i n g o f the mol i i n s i d e the vacuum chamber should be p r o v i d e d Other f e a t u r e s should be c o n s i d e r e d such as use o f s h i e l d e d a r c s means o f c y c l i n g m a t e r i a l i n t o and out o f the vacuim system w i t h o u t c o n t a m i n a t i n g the r e f r a c t o r y c a s t i n g s and the p o s s i b l e i n c o r p o r a t i o n o f c e n t r i f u g a l c a s t i n g t e c h n i q u e s Pressure p o u r i n g should be s t u d i e d as a way of r e d u c i n g s h r i n k a g e and m i c r o p o r o s i t y 3 A mold m a t e r i a l s and de s i g n improvement program i s r e q u i r e d t o reduce mold s h r i n k a g e reduce s u r f a c e r e a c t i o n s and c o n t a m i n a t i o n o f c o a t i n g s and t o p r o v i d e c l o s e t o l e r a n c e s P o s s i b l e approaches i n c l u d e use o f p r e c i s i o n rammed non r e a c t i v e m a t e r i a l s such as g r a p h i t e and h i g h t e m p e r a t u r e o x i d e c o a t i n g s Cooled permanent molds should be i n v e s t i g a t e d a l s o i n c l u d i n g the use o f c o n t r o l l e d d i r e c t i o n a l s o l i d i f i c a t i o n A An e x t e n s i v e program w i l l be r e q u i r e d t o p r o v i d e an adequate r e f r a c t o r y metals c a s t i n g t e c h n o l o g y T h i s program should p r o v i d e adequate c o n t r o l o f c a s t i n g t o l e r a n c e s and d e f e c t s ( p o r o s i t y s h r i n k a g e s e g r e g a t i o n g r a i n s i z e hot t e a r s p i n h o l e s e t c ) c o n t r o l o f m e l t and p o u r i n g t e m p e r a t u r e s adequate arc s t a b i l i t y and c o n t r o l o f o t h e r s i g n i f i c a n t v a r i a b l e s 5 Ap p l y the b a s i c r e f r a c t o r y m e t a l s c a s t i n g t e c h n o l o g y to i n d i v i d u a l columbium and molybdenum a l l o y s t o s o l v e s p e c i f i c problems a s s o c i a t e d w i t h the c a s t i n g o f these a l l o y s
77 PRIORITY RATING WORKSHEET CHART P R O f i R A M F A C T O R S PROaRAM PROBABIL ITY OF S U C C E S S D LOW MODERATE ⢠HI6H C R I T I C A L P R O B L E M S TO B E SOLVED ⢠FE>^/NOT TOO DIfFUIULT X 3 0 M E / D I F F I C U L T D M A N Y / VERY D IFF ICULT P R O C E S S G R O W T H P O T E N T I A L ⢠LITTLE OR O N O E F I N A B L E iZECOfiNllABLE m e W T I A L OTHER THAN AIR FORCE NONE SOME MANY Z 5 8 Z s 6 o 4 A P P L I C A T I O N S a O n 4 >C e NECESSITY FOR AIR FORCE FUNDIWa ⢠L O W HlfiH IMtttS l l V / c T H £ f t G o v r E F F d T ^⢠IWOOEHATE - Scut E F f o t T OTHce. ' S M C ^ i e S 8 D E K C U S l ^ E AiR FolUrt F U M p w a L I K C L V 12. N E E D F A C T O R S SYSTEMS PROBABILITY HIQH P B 0 B A 6 I ITY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y VERY HICH H I6H FAIR L O W F R E a U E N C Y OF REQUIREMENT I N S V « r E M M A R C THAN 3 COMPANEUTS Z 3 COMPlMENrs S I N G L E Cen/IPONENT DESIGN A L T E R M A T E S No ALTERNAre p o a e e e e N ONE ALTEIZNATC S E V E H A L A L T E R N A T E S M A T e R l A L S IMPLICAriON New MATERIAL PtVtU)J>U£NT CClS O MATEBIAL IMPROVfcMtlMT REffl D NO P R o o L E M F o i i e ^ e e N 12 8 4 tz 9 e> 3 3 2 I <5 6 3 6 4 o CALCOLATE S T E P I S T E P Z P R I O R I T Y 8 S Jo RAW SCORES FOR EACH REFERtMClP COMFCNCNT IN T A B L M A T END OF P A N E L RtPetT WITH BAtO TtrT^LS ENTERrP IN AT e i s M " S Y S T E M S A A R P RA>M scopes ^ II II 11 1 f 5 r " i r n i 11 1 ⢠⢠⢠c II 1 ⢠⢠⢠C II 1 ⢠⢠⢠c : II 1 II 1 m n r n r II 1 ⢠⢠⢠⢠⢠II 1 I L J ⢠n a n !⢠l O ⢠⢠⢠⢠\ n I L J ⢠⢠⢠⢠i r n ⢠⢠⢠L n i " n II 1 II 1 ⢠⢠⢠⢠II 1 ⢠⢠n i II 1 ⢠I J O L II 1 CIRCLE HIGHEST A A R P RAW S C O R & r ' 11 = IM EACH OTHER S Y S T E M C I R C L E NEXT H I G M E S T S C O e C IF WITHIN 4 P O I M T S O F T O P S C O R E n NUMBER OF S y s T E W S H I d H 3 - L O W ^ STEP 3 CIRCLE FREQUENCY DISTRIBUTION FACTOR f BELOWc I Z 3 B B Mee-e NUMBER. OF S Y S T E M S LOW 0 I 2 B Moize 1 0 I 4 1 1 1 3 1 H 1 2. 1 «f 1 4 TOTAL PRIORITY
- 7 8 - TITIE LARGE THIN WALL HIGH STRENGTH CASTINGS FROM TITANIUM ALLOYS AND MARAGING STEELS CHART PRIORITY R E U T E D C A M ! CHARTSt MANUFACTURING REQUIREMENT T i t a n i u m a l l o y s and maraging s t e e l s e x h i b i t i n g good minimum d u c t i l i t y (107 e l o n g a t i o n 2 i n c h ) and h i g h y i e l d s t r e n g t h / d e n s i t y (800 000 i n c h ) a t 1000 F are r e q u i r e d f o r c a s t i n g arge s t r u c t r a l bulkheads and frames (5 200 l b s ) S t r u c t u r e s up t o s i x f e e t i n l e n g t h lust be c a s t w i t h t h i c k and t h i n s e c t i o n s t h a t can be welded w i t h o u t c r a c k i n g or d i s t o r t i o n he f i n i s h e d c a s t i n g must meet t o l e r a n c e s o f + 0 010 i n c h I n o r d e r t o a v o i d f i n a l m a chining m 1 l a r g e m Th AARP REFERENCES f Chnrt . 47 B Chart . 31d P&FVPS Chart . APPLICABLE PROCESS Code TITANIUM VACUUM SKULL MELTING AND CASTING INTO CENTRIFUGAL MOLDS 1 01 12/1 02 07 MARAl'ING STEEL VACUUM MELTING AND CASTING INTO CERAMIC MOLDS 1 02 09 STATE O F THE ART ASSESSMENT T i t a n i u m A l l o y s At 800 F c a s t T i 6Al 4V has a y i e l d s t r e n g t h / d e n s i t y r a t i o o f 500 000 inche s Creep a t 800 F i s 77 a f t e r 10 000 hours a t UO k s i C a s t i n g s have been l i m i t e d t o dimensions o f 6 f t X 3 f t X 2 f t Minimira s e c t i o n t h i c k n e s s i s 3/32 i n c h (0 093) Dimensional t o l e r a n c e s achieved are + 0 020 up t o 3 i n c h l e n g t h s T i t a n i u m i s c a s t u s i n g a m o d i f i e d I n g o t f a c i l i t y i n c l u d i n g p r o v i s i o n s f o r e l e c t r o d e r e t r a c t i o n t i l t p o u r i n g and vacuum mold chambers f o r c e n t r i f u g a l l y f e e d i n g the m o l t e n m e t a l S k u l l m e l t i n g i s necessary t o p r e v e n t c o n t a m i n a t i o n o f the m e l t and c r u c i b l e burn t h r o u g h C e n t r i f u g a l c a s t i n g i s used t o improve f e e d i n g and reduce gas p o r o s i t y M i c h i n e d and rammed g r a p h i t e molds r e s u l t i n s u r f a c e c r a c k i n g and c o n t a m i n a t i o n problems Expendable rammed g r a p h i t e i s the most s a t i s f a c t o r y mold m a t e r i a l a v a i l a b l e Close t o l e r a n c e s are l i m i t e d by carbon p i c k u p from the g r a p h i t e molds Shrinkage o f mold m a t e r i a l i s 1/8 i n c h per f o o t M o i s t u r e and gas c o n t a m i n a t i o n o f mold m a t e r i a l I s a problem i n g o i n g from t h e molding oven t o the vacuum fur n a c e C y c l i n g o f molds and p a r t s I n and o u t o f the vacuum f u r n a c e IS slow and c o s t l y T h i s can be improved upon by development o f more s o p h i s t i c a t e d equipment M e l t s o f 400 pounds can be made w i t h p a r t s up t o 200 pounds produced A l l o y development f o r c a s t i n g s has c e n t e r e d on a l l o y s developed i n the 1950 1960 p e r i o d V e r y l i m i t e d q u a n t i t i e s o f h i g h q u a l i t y c a s t i n g s are a v a i l a b l e MaraRing S t e e l The y i e l d s t r e n g t h / d e n s i t y r a t i o o f 18 N i maraging s t e e l a t 1000 F I s 476 000 inche s The d u c t i l i t y a t 1000 F i s 247 and a t room temperature 117 Nominal p r o p e r t i e s have been d l f f i c j l t t o achieve i n scaled up p r a c t i c e due t o the d i f f i c u l t y i n a c h i e v i n g a u n i f o r m m i c r o s t r u c t u r e S e g r e g a t i o n has been p a r t i c u l a r l y troublesome i n heavy s e c t i o n s and causes b r i t t l e n e s s The mo l t e n m e t a l must be p r o t e c t e d f r o m t h e atmosphere Vacuum m e l t i n g reduces gas c o n t a m i n a t i o n and improves f l u i d i t y A l c o h o l v e h i c l e ceramic mold m a t e r i a l s have been used s u c c e s s f u l l y t o produce sound c a s t i n g s however the r e q u i r e d t o l e r a n c e s have not been achieved i n l a r g e t h i n w a l l s e c t i o n s Molds are preheated o u t s i d e o f t h e vacuum chamber i n a r Cycling, o f m a t e r i a l and p a r t s i n and ou t o f the fu r n a c e i s slow C a s t i n g s i z e s of 5 200 pounds can be produced c u r r e n t l y Continued on next page ALTERNATE PROCESSES FORCINGS EXTRUSIONS Code 2 01 00 2 03 00
79 CHART CRITICAL PROBLEMS T i t a n i u m 1 The predominant amount o f t i t a n i u m c a s t i n g s b e i n g produced are the T i 6 A l 4V or T i 5A1 2 5Sn a l l o y s These a l l o y s have comparable mechanical p r o p e r t i e s each h a v i n g a y i e l d s t r e n g t h / d e n s i t y r a t i o of a p p r o x i m a t e l y 800 000 inches a t lOOOF The r e q u i r e m e n t s i n the 1970 85 time p e r i o d are 800 000 Inches a t lOOOF Research t o develop a c a s t a l l o y w i t h p r o p e r t i e s s u p e r i o r t o those o f T i 6A1 4V have no t been to o encouraging Heat t r e a t m e n t of t h i s alpha beta a l l o y w i l l produce an i n c r e a s e i n s t r e n g t h but a l o s s i n d u c t i l i t y 2 Mold m a t e r i a l s have l i t t l e e f f e c t on t h e mechanical p r o p e r t i e s o f t i t a n i u m copper s t e e l s o l i d g r a p h i t e and rammed g r a p h i t e are s u f f i c i e n t l y i n e r t mold m a t e r i a l s f o r c a s t i n g t i t a n i u m Molds machined from copper s t e e l or s o l i d g r a p h i t e are most s u i t a b l e f o r simple shapes where no r e s t r i c t i o n t o s o l i d i f i c a t i o n e x i s t s I f t h e r e i s r e s t r i c t i o n t o s o l i d i f i c a t i o n rammed g r a p h i t e i s used as the mold m a t e r i a l G r a p h i t e molds c o n t a m i n a t e t h e s k i n o f the c a s t i n g w i t h carbon T h i s n e c e s s i t a t e s the removal of 10 t o 15 m i l s from t h e s u r f a c e by chemical m i l l i n g 3 M e t a l permanent type molds can be used e f f e c t i v e l y t o produce s m a l l e r c a s t i n g s r e l a t i v e l y f r e e from d e f e c t s such as gas p o r o s i t y and m i c r o s h r i n k a g e However long t h i n s e c t i o n s case i n m e t a l molds are apt t o have p o r o s i t y r e s u l t i n g from s h r i n k a g e and s h r i n k a g e v o i d s as d e f e c t s 4 Vacuum f u r n a c e s now being used t o m e l t t i t a n i u m are l i m i t e d e n t i r e l y t o the consumable e l e c t r o d e s k u l l m e l t i n g f u r n a c e T h i s type f u r n a c e has l i m i t e d c a p a b i l i t y i n t h a t the losses due Co s k u l l f o r m a t i o n reduce the e f f i c i e n c y o f the c a s t i n g process Here i t i s e s t i m a t e d t h a t the s k u l l f o r m a t i o n accounts f o r a p p r o x i m a t e l y one f o u r t h o f the m e l t The h i g h super heat r e q u i r e d causes problems of g r a i n s i z e c o n t r o l Maraelng S t e e l s 1 P r e s e n t c a s t i n g a l l o y s do not meet the s t r e n g t h r e q u i r e m e n t s F u r t h e r a l l o y development i s needed t o p r o v i d e a l l o y s w i t h improved e l e v a t e d t e m p e r a t u r e p r o p e r t i e s Research done t h u s f a r t o produce c a s t a l l o y s w i t h h i g h e r s t r e n g t h p r o p e r t i e s has n o t met w i t h a g r e a t d e a l o f success There i s some l a c k of u n i f o r m r e p r o d u c i b i l i t y m p r o p e r t i e s The as case a l l o y s are prone t o s e g r e g a t i o n w h i c h r e s u l t s i n a decrease o f d u c t i l i t y T h i s troublesome s e g r e g a t i o n problem may become more pronounced as a l l o y s t r e n g t h i n c r e a s e s 2 The molds and mold m a t e r i a l s p r e s e n t l y b e i n g used t o c a s t these a l l o y s are n o t c o n s i d e r e d CO be capable o f p r o d u c i n g c a s t i n g s Co the r e q u i r e d t o l e r a n c e s 3 To p r o v i d e t h e complete c a p a b i l i t y t o p e r f o r m weld r e p a i r and b u i l d up of complex s t r u c t u r e s the w e l d a b i l i t y o f Che maraglng s t e e l s must be c o n s i d e r e d I n g e n e r a l t h e r e appear Co be C h r e e major problems (1) poor weld meCal toughness i f w e l d i n g processes o t h e r t h a n gas t u n g s t e n a r c i s used on heavy s e c t i o n s (2) h e a t a f f e c t e d zone c r a c k i n g i n banded base m e t a l s t r u c t u r e s and (3) reduced s t r e s s c o r r o s i o n c r a c k i n g r e s i s t a n c e i n welds 4 improvement i s r e q u i r e d i n mold m a t e r i a l d e s i g n T h i s improvement w i t h t h e use o f d i r e c t i o n a l s o l i d i f i c a c i o n t echniques w i l l decrease Che number o f c a s t i n g d e f e c t s PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop l a r g e w e l d a b l e c l o s e t o l e r a n c e s t r u c t u r a l frame and bulkhead c a s t i n g s of t i t a n i u m a l l o y s and maraging s t e e l s f o r e l e v a t e d temperature s e r v i c e BACKGROUND T i t a n i u m C a s t i n g s i z e and w e i g h t r e q u i r e m e n t s are n o t a problem even today The d i f f i c u l t r e q u i r e m e n t s t o a c h i e v e a r e the + 0 010 i n c h t o l e r a n c e s and s t r e n g t h l e v e l s A l l o y development p r o l a b l y w i l l i n v o l v e an a g i n g r e a c t i o n superimposed on basic a l l o y systems i e 5A1 2 5Sn To 6A1 4V and Ti-13V 11 Cr 3Al New Continued on next page
- 8 0 - CHART NO âIQrl PROPOSED DEVELOPMENT PROGRAM, c o n t i n u e d c o m p e t i t o r s are emerging I n the c a s t i n g area w h i c h w i l l promote t e c h n i c a l advances and w i l l expand t h e t e c h n o l o g y A s t r o n g v i g o r o u s a t t a c k on these key problems should produce c a s t i n g s h a v i n g the d e s i r e d p r o p e r t i e s Maraging S t e e l C a s t i n g s i z e and we i g h t r e q u i r e m e n t s can be met w i t h today s te c h nology Close t o l e r a n c e s w i l l r e q u i r e emphasis on mold m a t e r i a l s t h e r m a l c o n t r o l s and vacuum degassing Improvements S e g r e g a t i o n i s a s e r i o u s problem and r e q u i r e s d e t a i l e d study T h i s I s n o t c o n s i d e r e d t o be an unsurmouncable problem I t i s f e l t t h a t an a l l o y development program can be conducted s u c c e s s f u l l y t o p r o v i d e c a s t i n g a l l o y s w i t h s u i t a b l e mechanical p r o p e r t i e s APPROACH T i t a n i u m To meet the r e q u i r e m e n t s f o r t i t a n i u m c a s t i n g I n t h e 1970 1985 time p e r i o d a number o f p a r a l l e l programs must be conducted t o s o l v e the many d i f f i c u l t problems 1 A program i n a l l o y development i s needed i n o r d e r t o p r o v i d e a l l o y s w i t h improved e l e v a t e d t e m p e r a t u r e p r o p e r t i e s 2 A c o n s i d e r a b l e amount o f a t t e n t i o n must be g i v e n t o d e s i g n and Improvement o f mold m a t e r i a l s I n d i c a t i o n s are t h a t permanent molds o f f e r a g r e a t d e a l o f promise i f some of the problems a s s o c i a t e d w i t h t h e i r use can be overcome M e t a l permanent molds are p a r t i c u l a r l y a t t r a c t i v e i n m a i n t a i n i n g t o l e r a n c e s i n t h i n s e c t i o n s Ceramic r e f r a c t o r y mold c o a t i n g s and washes should be f u r t h e r developed t o reduce s u r f a c e r e a c t i v i t y w i t h the mold and t o improve s u r f a c e f i n i s h 3 The problem o f inadequate m e l t i n g and c a s t i n g equipment should be s t u d i e d w i t h a view toward i m p r o v i n g m a t e r i a l s h a n d l i n g d u r i n g the complete c a s t i n g c y c l e Of p a r t i c u l a r concern i s the n e c e s s i t y t o p r o v i d e f u r n a c e equipment which w i l l p e r m i t p r e h e a t i n g molds i n the f u r n a c e atmosphere T h i s procedure w i l l decrease m a t e r i a l s c y c l i n g time and a t the same ti m e decrease the number o f c a s t i n g d e f e c t s The o x i d i z e d aluminum molds used i n some p r o p r i e t a r y processes should be i n v e s t i g a t e d as a permanent mold m a t e r i a l as w e l l as the u s u a l copper and s t e e l molds 4 A program i s needed f o r i m p r o v i n g c u r r e n t m e l t i n g p r a c t i c e s which w i l l i n c ease the y i e l d o f the m e l t and a t the same time reduce power r e q u i r e m e n t s Reactions between the mold m a t e r i a l and the m e l t must be minimum i n o r d e r t o achieve these o b j e c t i v e s Maraging S t e e l s I f one c o n s i d e r s the p r e s e n t s t a t e o f the a r t and t h e c r i t i c a l problems t o be so l v e d i t i s not unreasonable t o expect t h a t the g o a l s o f the 1970 1985 time p e r i o d can be met f o r t h i s c l a s s o f m a t e r i a l s A program i s needed f o r s u b s t a n t i a l l y I m p r o v i n g the s t r e n g t h p r o p e r t i e s o f ma r a t l n g c o m p o s i t i o n s At the same time some a t t e n t i o n must be g i v e n t o develop s u i t a b l e w e l d i n g t e c h n i q u e s i n c l u d i n g f i l l e r r o d development I n w o r k i n g maraging s t e e l s t o wrought forms some r e g i o n s o f i n t e r d e n d r i t i c s e g r e g a t i o n are f l a t t e n e d and l a t e r cause a banded m i c r o s t r u c t u r e T h i s banded m i c r o s t r u c t u r e causes a n i s o t r o p i c mechanical p r o p e r t i e s which are a l s o p r e v a l e n t I n weld heat a f f e c t e d zones Welding s t u d i e s and f i l l e r rod development should a l s o be d i r e c t e d towards e l i m i n a t i n g the banded m i c r o s t r u c t u r e M e l t i n g p r a c t i c e s should be improved t o c a p i t a l i z e on the economics o f a i r m e l t i n g as compared t o vacuum m e l t i n g Here a program i s needed t o stu d y the adequacy o f m e l t i n g under a p r o t e c t i v e s l a g and p o u r i n g i n t o an evacuated mold chamber or i n an argon i n e r t atmosphere I t w i l l be necessary t o reduce t o a minimum the time the m e l t i s exposed t o ambient environment Continued on next page
- 8 1 - CHART ^ ^ , NO i^-t APPROACH. Maraglng S t e e l s , c o n t i n u e d The problem o f s e g r e g a t i o n i n maraglng a l l o y s must be s o l v e d i f h i g h e r s t r e n g t h a l l o y s are t o be produced I n s t u d y i n g the p a t t e r n o f s e g r e g a t i o n a r a d i o a c t i v e t r a c e r element h a v i n g atomic m o b i l i t y s i m i l a r t o t h a t o f n i c k e l c o u l d be used t o s t u d y f l o w p a t t e r n s d u r i n g f r e e z i n g p a r t i c u l a r l y d u r i n g times when d e n d r i t i c s e g r e g a t i o n o c c u r s
82 PRIORITY RATING WORKSHEET CHART P R Q g R A M P A C T O a S PROaRAM P R O B A B I L I T Y O F S U C C E S S ⢠LOW X MODERATE ⢠HiaH C R I T I C A L P R O B L E M S TO B E S O L V E D ⢠F E W / N O T Too DIFFICULT Jt 3 0 M E / D I F F I C U L T P M A N Y / V E R Y D I F F I C U L T P R O C E S S G R O W T H P O T E N T I A L D L I T T L E O R O N D E F I N A B L E ^ (^ECO<3NI^ABLE P O T E N T I A L A P P L I C A T I O N S O T H E R T H A N A I R F O R C E ⢠N O N E n S O M E X M A N Y N E C E S S I T Y FOR AIR F O R C E F U N D I N G ⢠⢠z 5 8 Z s 6 o 4 o 4 6 LOW HI6H IM I t tS t t tV /c rHE* GOVT C F F C C T * lneotttATs - 5<iDiE C F n c r o r n « â¢SoMeces e ttccuis\¥£ A I R Foftct F U M P M ^ LIKEL<< i t N E E D F A C T O R S S Y S T E M S P R O B A B I L I T Y HiaH PROBABIL ITY FAIR. P R O B A B I L I T Y LOW P R O B A B I L l T y COMPONENT C R I T l C A L I T Y V E R Y H I C - H HlfiH F A I R L o w F R E f l U E N C Y OF REQUIREMENT IN S Y S T E M MORE THAN 3 COMPONENTS 2. 3 COMPcNENTS S I N G L E ( C O M P O N E N T D E S I & N A L T E R M A T E S No ALTERNATE R n E S E E N ONE ALTERNATE S E V E R A L A L T E R N A T E C M A T E R I A L S I M P L I C A T I O N New MATERIAL PevtLOfMENT CCO V MltTCRlAL IMPROVbMCNT E E S D NO PRO&LEM F o U C S E E N 12 8 4 n 9 b 3 3 2 I <9 6 3 6 4 o CALCULATE S T E P I S T E P S P R I O R I T Y 8 8 3e R A W S C o « S F O R E A C H REFCIteNOCP C O M F O N C U T IN T A K L U A T L M S or PANEL RtP««.T W I T H B A W T O T A L S E N T E R C P M <3UIUUAtV AT IZISMT S Y S T I M S 2& CIRCLE HIGHEST A A R P RAW S C O R E n s IN EACH CTHER S Y S T E M C I R C L E NEXT H I G H E S T S C O R E IF WITHIN 4 P O I N T S O F T O P S C O R E n " NUMBER OF g y s T E M S H idH / L O W O S T E P 3 C I R C L E N U M S E R OF S Y S T E M S LOW F R E Q U E N C Y D ISTRIBUTION F A C T O R NuMsen. oc sysreM4 Hi&ri I 2, 3 O K M M L E BELOWi 0 1 2 R MOU 1 0 1 a I 4 1 1 1 3 1 f 1 z 1 Â«Ì 1 4 A A R P RA>N SCORES ] ⢠⢠! ] ⢠⢠: ] ⢠⢠! : ] ⢠⢠[ ] ⢠⢠⢠⢠⢠⢠⢠⢠T O T A L PRIORITY
83 TITLE ROLLING OF WIDE SUPERALLOY SHEET AND FOIL CHART / . 2 V PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT To p r o v i d e f l a t r o l l e d p r o d u c t s o f p r e c i p i t a t i o n and d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s p r i n c i p a l l y n i c k 1 base i n th i c k n e s s e s from 0 006 t o 0 120 i n c h w i t h + 5 percent t h i c k n e s s coli-rance i n w i d t h s up t o 96 inches Wide sheet and f o i l p r o d u c t s are d e s i r e d t o minimize j o i n t wei^jht p e n a l t i e s i n v e r y l a r g e s t r u c t u r a l panels such as l i f t and c o n t r o l s u r f a c e s and r i g i d si.bstr c c i r e a i r i n l e t s and d u c t i n g s t r u c t u r a l s t i f f e n e d canning f o r r a d i a t i o n s h i e l d i n g heat s h i e l d s t h r u s t s t r u c t u r e s and s p a c e c r a f t r a d i a t o r s AARP REFERENCES F rhnrtc . R rhnrt. 3. 11. 15a.b. 16a.b. 20a. 30b,c. 32b, 41b.c. 42b,c, 50a, 92. 110a,b. 122b,c PAF\/P<: rhort. APPLICABLE PROCESS COLD ROLLING ON jSENDZIMIR OR SIMILAR CLUSTER MILL WITH INTERMITTENT AND FINAL ANNEALS AS REQUIRED Code 2 02 09 STATE OF THE ART ASSESSMENT The r e q u i r e d sheet t o l e r a n c e l i m i t s r o l l i n g m i l l c h o i c e t o the c l u s t e r c o n f i g u r a t i o n Maximum pro d u c t w i d t h f o r present c l u s t e r m i l l f a c i l i c i e s i n Che United S t a t e s i s 52 inches w i t h 36 Co 48 i n c h w i d t h s being more common i n house l i m i t s f o r Che s u p e r a l l o y producers M i l l designs have been made f o r widchs up t o 144 inches However market r e q u i r e m e n t s have been j ged i n s u f f i c i e n t f o r the c a p i t a l investment r e q u i r e d t o extend w i d t h c a p a b i l i t y I t has been i n d i c a t e d i n p r i v a t e communications from Michael G Sendzlmir t h a t i n d u s t r y i s c u r i e n c l y c o n s i d e r i n g p r o d u c t i o n o f 72 in c h wide s t a i n l e s s s t e e l Expansion t o the 96 i n c h i i d c h s j i M depend on requiremenCs As an a l c e r n a t e approach to Che r o l l i n g o f such wide sheet narrower sheets might be j o i n e d by w e l d i n g or ot h e r mechods T h i s approach mlghc s u f f i c e f o r c o n v e n t i o n a l m a t e r i a l s b c d i s p e r s i o n screngchoned a l l o y s e x h i b i t such poor j o i n t e f f i c i e n c i e s t h a t t h i s i s not a s a t i s f a c t o r y approach Should f u t u r e a l l o y development a l l e v i a t e t h i s problem t h i s c o u ld circumvent Che need f o r sheet r o l l i n g f a c i l i t i e s o f wider c a p a c i t y CRITICAL PROBLEMS Wide c l u s t e r m i l l s and necessary a c c e s s o r i e s are not a v a i l a b l e ALTERNATE PROCESSES HOT PACK ROLLING WITH MECHANICAL FINISHING TO ATTAIN GAUGE AND FINISH WELDING OF NARROWER SHEET Code 2 02 10 6 01 00
PROPOSED DEVELOPMENT PROGRAM OBJECTIVE Est I l i s h a c a p a b i l i t y f o r producing c l o s e t o l e r a n c e s u p e r a l l o y sheet up t o <J6 i n c h w i d t h s BACKGROUND Thi_ v a l u e o f d e s i g n i n g v e r y l a r g e h i g h performance systems w i t h wide c l o s e t o l e r a n c e sheet was shown d u r i n g i n i t i a l d e s i g n s t u d i e s f o r a i r c r a f t such as the B 7 0 b j t the a t t e n d a n t c o s t was h i g h Future v e r y l a r g e systems can be expected CO i n v o l v e s i m i l a r q u e s t i o n s but f o r d i f f e r e n t a l l o y s where f a c i l i t y i n s t a l l a t i o n s wo 1 1 be c o s t l y and would have t o be j u s t i f i e d a f t e r c a r e f u l e x a m i n a t i o n o f a l t e r m c i v c s i n design and t h e i r e f f e c t on systems performance I t i s b e l i e v e d t h a t these t r a d e and value analyses can be performed w e l l i n advance of systems develop ment d e c i s i o n s and i n time t o a l l o w the necessary equipment and process develop ment lead time i f such a c t i o n i s i n d i i . a t e d APPROACH 1 Using the AARP d e s c r i p t i o n s o f components and p o t e n t i a l systems as a guide conduct an e n g i n e e r i n g trade s t u d y o f the s t r u c t u r a l p e n a l t i e s a s s o c i a t e d w i t h v a r y i n g w i d t h f l a t r o l l e d p r o d u c t s o f weldable and non weldable a l l o y s C o r r e l a t e s t r u c t u r a l w e i g h t e f f i c i e n c i e s w i t h v e h i c l e o p e r a t i o n a l g a i n s I n p u t s f o r these s t u d i e s come i n p a r t from c u r r e n t i n d u s t r y p r o p o s a l s f o r advanced systems and from i n d u s t r y i n house s t u d i e s augmented by more d e t a i l e d s t r u c t u r a l analyses when needed 2 I f the v a l u e o f wide c l o s e t o l e r a n c e s u p e r a l l o y sheet i s v e r i f i e d by these s t u d i e s prepare s p e c i f i c product d e s c r i p t i o n s i n terms of p r o p e r t i e s w i d t h t h i c k n e s s t o l e r a n c e s and f a b r i c a b i l i t y 3 Design an a p p r o p r i a t e c l u s t e r m i l l w i t h necessary accessory equipment I f Government requirements are s u f f i c i e n t i n q u a n t i t y i t i s b e l i e v e d t l a t i n d u s t r y would c o n s t r u c t the necessary f a c i l i t i e s w i t h o u t a d d i t i o n a l government support
85 PRIORITY RATING WORKSHEET CHART NO _ PRQgjpAM FACT9RS PROfiRAM PROBABIL ITY OF S U C C E S S ⢠LOW ⢠MODERATE C R I T I C A L P R O B L E M S TO B E SOLVED TC F E W / N O T TOO D I F F I C U L T ⢠SOME / D I F F I C U L T 3 Q M A N Y / VERY DIFF ICULT 8 P R O C E S S G R O W T H P O T E N T I A L ⢠LITTLE OR U N D E F I N A B L E O eeco6Hni^Bie poreMriAL 4 APPLICATIONS OTHER T H A N AIR FORCE ⢠NONE o SOME 4 n MANY 6 N E C E S S I T Y FOR A I R FORCe F U N D I N G ⢠LOW Hiâ¬H iNtuSTHV/^crrHCA & o v r ereotr ⢠MooERATE - sme erfotx oryux. X eici:LiisiyE A IR FoAct F U N D N & L I K C L ' / I t p s N E E D F A C T O R S S Y S T E M S P R O B A B I L I T Y H I G H P R O B A B I L I T Y F A I R P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T l C A L I T Y VERY HIiTH HI<KH FAIR L o w F R E Q U E N C Y OF REQUIREMENT IN -SYSTEM MORE THAN 3 COMPONENTS Z 3 CeMPONENrS S I N G L E eeMPONENT 0 E S I 6 N A L T E R M A T E S No ALTERNATE R W E S E E N ONE AUTERNATE S E V E R A L A L T E R N A T E * M A T E R I A L S IMPLICATION New M A E R l A L PEV U3<>M£NT CClS O MATERIAL IMPflOVtMENT R£(9 0 W PROBLEM F o R t s e e N CALCULATE P R I O R I T Y RA>N SCORES S T E P I S T E P 2 CIRCLE HIGHEST A A R P RAW S C O R E IN EACH OTHER S Y S T E M C I R C L E NEXT H I G H E S T S C O R E IF WITHIN 4 P O I N T S O F T O P S C O R E N U M B E R OF ^VSTEMS H idH ^ S T E P 3 C I R C L E NUMBER OF S Y S T E M S L o w F B E O U E N C Y DISTRIBUTION F A C T O R NUMSEfL OP S Y S T E M S Hiart I 2 I 1â 0 I 2 RMoee 1 0 t a I 0, 1 1 1 3 1 *f 1 z 1 «f A A R P SVST MS B2& <rfAp RAW SCORES FOR E A C H REFCRENCEP COMPONCMT IN TA&LEj AT END or PANEL IZtPOtT WITH R A W T O T \ L S ENTEREP M <3UiU>tAtV AT EIGHT TOTAL BELOWt 3 OR M o e £ PRIORITY
-86 TITLE CHART PRIORITY ROLLING OF CLAD SHEET AND FOIL NO /a. 5 RELATED CAMR CHARTS AARP REFERENCES E Chnrt. 1 B Charts la 3 P i F V P S Chart* APPLICABLE PROCESS EXPLOSIVE OR HOT ROLL BONDING PLUS SECONDARY HOT/COLD ROLLING INTERMEDIATE AND FINAL HEAT TREATMENT Code 7 09 01 7 09 03 MANUFACTURING REQUIREMENT Provide stainless steel or superalloy sheet and f o i l clad w i t h precious metals for resistance to corrosive fuels and exhausts Flat r o l l e d products must have minimum r a t i o of clad to core consistent w i t h corrosion protection required so as to minimize s t r u c t u r a l weight penalty and must be formable i n t o pressure vessels tanks and other structure without delamination Total thickness anticipated ranges from 0 005 inch to 0 100 inch + 57 in sizes to 96 inches wide x 144 inches long The long f l i g h t duration vehicles would imply the need for large minimum weight tanks and consequently large f l a t r o l l e d product to minimize s t r u c t u r a l j o i n t s In conventional hot bonding operations low d u c t i l i t y b r i t t l e phases are formed in the bond zone between the base metal and the clad which cause cracking and delamination during subsequent forming or secondary working Thus production of large composite packages has been l i m i t e d to materials that do not form such b r i t t l e phases on exposure to the high tempera tures required for hot bonding The recent development of explosive cladding procedures has given a method for minimizing the formation of b r i t t l e i n t e r m e t a l l i c phases i n the bond zone Composites of titanium to steel have been made i n the size ranges required Smaller composites 12 x 12 to 24 x 96 have been made between palladium and columbium columbium and stainless steels tantalum and stainless steels,and tantalum and Hastelloy The strength requirement for the pressure vessel and tanks i s that the strength/density a t l o hould be 7 50 000 Inches The clads made to date f a l l i n the ange of 120 to 450 000 inches Assuming that a base metal with the desired strength i s available the only additional requirement imposed by the explosive cladding operation i s that s u f f i c i e n t d u c t i l i t y be present to withstand the explosive forces Thus the required composite forms appear to be te c h n i c a l l y feasible but have not been demonstrated The size and thickness requirements cannot be met on commercially available equipment This subject is treated i n CAMR 124 An alternate would be to form the tanks and vessels by welding smaller clad sections together Welding of clad assemblies without degrading properties is d i f f i c u l t and yet to be demonstrated for the precious metal high strength combinations desired CAMR 435 discusses the fusion welding problems and techniques CRITICAL P v C ' E S 1 Rolling composites of high and low strength alloys w i t h variance i n expansion c o e f f i c i e n t w h i l ^ maintaining desired r a t i o of clad to core 2 Minimizing i n t e r m e t a l l i c ( b r i t t l e phases) formation during warm or hot r o l l i n g and heat treatment 3 Rolling f a c i l i t i e s for widths up to 96 inches and thicknesses down to 0 005 See Chart 124, 4 Welding of di s s i m i l a r a l l o y compositions without undue s t r u c t u r a l degradation ALTERNATE PROCESSES 1 EXPLOSIVE BOND AT FINAL GAUGE ( p a r t i c u l a r l y suited for pressure vessels and tanks) 2 MELT DUPLEX INGOTS AND WORK TO SIZE 3 COLD ROLL BONDING Code 7 09 03 1 01 00 7 09 01
PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop a process for converting to the required sheet and f o i l a large composite package of a precious metal clad to a stainless steel or superalloy core The r e s u l t i n g product w i l l be evaluated by hardware production APPROACH 1 Technical f e a s i b i l i t y studies on hot and explosive bonding for sp e c i f i c composite combinations should be i n i t i a t e d on a scale which would provide xnforma t i o n for process scale up The i n i t i a l portion of the program should be directed at establishing optimum bonding technique for the desired precious metal-high strength combinations needed The c r i t e r i a for evaluating the bonding operation would be the absence of b r i t t l e phases i n the bond zone and a b i l i t y of a composite to withstand the bonding operation I t s e l f The most promising cladding procedure would be then selected f o r process studies I n these studies the composite thickness clad to base metal r a t i o s cold/warm r o l l i n g sequences and intermediate annealing procedure would be established 2 The products available from the small scale study would be evaluated by producing simulated pieces of hardware to ensure that a r t i c l e s can be formed without delamination F i n a l l y welding procedures should be Investigated f o r j o i n i n g of small parts i n t o larger sections See CAMR 435 for a description of welding techniques 3 I f welding procedures are successfully established the next phase of program would be to scale up to the largest sizes that could be commercially manufactured I f on the other hand I t Is not possible to produce s a t i s f a c t o r y welding assemblies a market survey should be made to see i f a need for the type and size of r o l l i n g m i l l s required could be established for Industry I f there is no i n d u s t r i a l need f o r r o l l i n g m i l l s capable of producing material at widths to 96 inches and thicknesses to 0 005 inches ' government support would be required
88 PRIORITY RATING WORKSHEET CHART PRQg^pAM FACTORS PROGRAM PROBABILITV OF SUCCESS D LOW 2. MODERATE 5 ⢠HI&H S CRITICAL PROBLEMS TO BE SOLVED n FEVV/NOT TOO DIFFICULT Z J 5 SOME/DIFFICULT S Q MANY/ VERY DIFFICULT S PROCESS GROWTH POTENTIAL ⢠LITTLE OR yNDEFINAOLE O ^ KrC06NirABLE POTEMTIAL 4 APPLICATIONS OTHEB. THAN AIR FORCE ⢠NONE O >C SOME H D MANY 0 NECESSITY FOR AIR FORCE FUNDIMO ⢠LOW HlfiH IMPUSTtty/«TH£« <iO»r CFFOCT 4 ⢠|M»t>eiiATE - ^mC EFCMLT OTHCd SMCCeS S ^ excuisive A IH F»Acb F U M P M & UKCL<< \I. NEED FACTORS SYSTEMS PROBABILITY HIQH PBOBABILlTY FAIR PROBABILITY LOW PROBABILITY COMPONENT CRITICALITY VERY HICH HIAH FAIR Low FREOUENCy OF R E a U l K E M E N T IN SYSTEM MORE THAN 3 COMPONENTS 7. 3 COMPCNENTS SINflLE COMPONENT O e e i a N A L T E R N A T E S No ALTERNATE RwESEEN ONE ALTERNATE SeVEIlAL ALTERNATE* MATECIAL3 IMPLICATION New MATERIAL DeVblOfUEMT REiS O MATtClAL IMPUOVEMENT CElB D NO PaoatEM FoftEscEH IZ 8 4 l i 9 & 3 3 2 1 "5 6 3 6 4 o CALCULATE S T E P I S T E P 2 PRIORITY /2 HAW SCORES FOR EACM REFceeNfcP COMPONENT IN T A & L U AT t N D OF PANEL tJEPOtT W I T H 12AI0 T O T A L S ENTERCP M AT eiSMT S V S T e M S /9 / CIRCLE HIGMCST A A R P RAW S C O R E n = IN EACH OTHER S V S T G M C I R C U E NEXT HICSMEST IF WITHIN 4 P O I N T S O F T O P S C O R E n NUMSER OF SySTEWS HldlH / L O W ^ S T E P 3 C i R C u e NUMBER OF SYSTEMS LOW F R E O U E N C Y DISTRIBUTION F A C T O R MUMOen OP svsn^Mf HiaH I 2 3 OB N W U S C O R E B E L O W i 0 I 1 0 1 a 1 4 1 1 1 3 1 z 1 «f 1 *f ⢠c ⢠c ⢠⢠I ⢠⢠I l a c ⢠⢠I ⢠⢠I ⢠c z i i ⢠⢠I ⢠c B ⢠T O T A L P R I O R I T Y
89 TITLE PRODUCTION OF VERY FINE (0 0002 inch dla ) SUPERALLOY WIRE IN LONG CONTINUOUS LENGTHS CHART NO PRIORITY RELATED C A M ^ C H ^ T S MANUFACTURING REQUIREMENT To produce long continuous lengths (on Che order of 30 000 f t ) of 0 0002 Inch -K) 0001 Inch 0 0000 Inch diameter wire from n i c k e l or cobalt base superalloys Wire should have a minimum ultimate strength of 100 000 p s i at 1800 F and 10 percent minimum elongation This very f i n e superalloy wire In large q u a n t i t i e s (several thousand pounds) and of continuous length i s needed for making wire strands or yarn to be used for the manufacture of m e t a l l i c rope or woven f a b r i c s AARP REFERENCES E Charts 301 B Charts 302 lA5b 149b 150b P8FVPS Char ts . APPLICABLE PROCESS (A) COLD DRAWING WIRE THROUGH SUCCESSIVE DIES WITH INTERMITTENT ANNEALS (B) BUND1£ DRAWING or (C) MELT SPINNING (A) 2 o f ^ (B) 2 05 03 (C) 2 05 06 STATE O F THE ART ASSESSMENT Materials having the specified mechanical properties are not available i n wire form at t h i s time Based on the l i m i t e d data available today the strongest superalloys w i l l have an ultimate t e n s i l e strength of 90 000 p s i at 1800 F Elongation requirements also appear d i f f i c u l t to meet Cold Drawing Wire through Successive Dies w i t h I n t e r m i t t e n t Anneals Fine wire on the order of 1/2 m i l (0 0005 ) diameter can be produced today by the conventional wire drawing process u t i l i z i n g a succession of diamond dies each w i t h a smaller hole At least two p r o p r i e t a r y superalloys have been drawn i n t o wire by the conventional process to a diameter of 0 0002 inch i n lengths of approximately several thousand feet This has been accomplished i n the l a s t phases of drawing by reductions of approximately 15 percent per pass and w i t h as many as 20 dies i n succession As many as 100 dies are required to reduce wire from 0 001 inch to 0 0002 inch diameter An Important factor i s equal reduction and/or drawing force between successive dies The use of l i q u i d lubricants i s a w e l l defined a r t and normal progress should provide s u f f i c i e n t c a p a b i l i t y for Che 1970-1985 period Further aids to drawing such as ultrasonics should be standard practice i n the near future Associated processes such as pointing degreasing annealing and coating are w e l l advanced and w i l l be w i t h i n the required state of the art The major d i f f i c u l t y at the present state of the a r t i s to obtain diamond dies possessing a high degree of u n i f o r m i t y w i t h respect to wear for drawing long continuous lengths of 30 000 f t or more Dies can be made but the conventional d r i l l i n g of the diamond dies i s exceedingly tedious w i t h very long lead times The arc-spark discharge process and the laser d r i l l i n g process are possible solutions to the problem and should be Investigated further The laser process i s p o t e n t i a l l y a lower cost method of achieving the desired r e s u l t s Another d i f f i c u l t y i s that a wire drawing machine u t i l i z i n g m u l t i p l e dies and the necessary b u i l t - i n controls i s not available but must be t a i l o r made The knowledge to do ALTERNATE PROCESSES NONE Continued on next page Code
CHART 90 STATE OF THE ART ASSESSMEWI, continued t h i s e x i s t s With present state of the a r t no problem is anticipated i n producing large q u a n t i t i e s of continuous length wire having a diameter of 0 00045 inches or larger Bundle Drawing Development work now i n progress Contract No AF33(615) 5063 shows considerable promise for producing f l e x i b l e m u ltifilament m e t a l l i c yarn by the bundle drawing process Type 304 stainless and the proprietary Chromel R have been drawn i n t o 0 0045 inch diameter yarn (7500 f t long) which is composed of many filaments of 0 0005 inch diameter wire There i s optimism that superalloy yarn composed of 0 0002 inch diameter filaments w i l l be available for the designated time period In t h i s process several rods of copper clad a l l o y the a l l o y being perhaps 1/8 inch diameter and 3 feet long are inserted i n t o a larger copper tube and sealed The composite IS f i r s t r o l l e d then drawn through successive dies u n t i l the f i n a l diameter say 0 0045 inch IS obtained The copper is than leached away and the filaments are twisted to form a compact smooth yarn The number of filaments i n a yarn may vary over a wide range e g 90 to 300 depending on design requirements (For information only the yarn may be coated w i t h polyvlnylalcohol for ease of weaving i n t o m e t a l l i c c l o t h The coating I s then removed i n hot water) Melt Spinning Fibers of Chromel R and nic k e l base superalloys with diameters between 0 0015 inch and 0 013 inch and lengths up to 77 inches have been produced using a melt spinning process where molten metal i s forced through a small o r i f i c e i n t o a v e r t i c a l freezing chamber The objective i n t h i s current development work i s 0 0005 inch diameter i n continuous long lengths (see Air Force Project Nr 149 7) and up to 2000 pounds of packaged filament CONCLUSION I t IS believed that as a r e s u l t of c u r r e n t l y sponsored programs the required c a p a b i l i t y w i l l e x i s t by 1970 or s h o r t l y thereafter Present e f f o r t should continue undiminished but no f u r t l e r manufacturing development is proposed other than as outlined i n CAMR 306 concerning precision d r i l l i n g of small holes i n diamond dies
91 TITLE EQUIPMENT FOR PRECIPITATION STRENGTHENED HEAT TREATMENT OF SUPERALLOY FINE WIRE STRAND UP TO 0 25 INCH DIAMETER CHART NO PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Development of furnace equipment to p r e c i p i t a t i o n strengthen 0 25 inch diameter superalloy wire strands (made from 0 001 inch diameter wire) at high temperature under an i n e r t atmosphere to achieve an ultimate t e n s i l e strength of at least 100 000 p s i at 1800 F I t i s desired that t h i s heat treatment be carried out i n sequence w i t h the wire drawing f i n a l annealing and stranding process AARP REFERENCES E C h a r t s . B C h a r t s . 308 146 PSFVPS Char ts . APPLICABLE PROCESS Either (A) BATCH HEAT TREATMENT or (B) CONTINUOUS STAND HEAT TREATMENT (A) (B) Code 4 01 01 4 01 02 STATE O F THE ART ASSESSMENT Batch Heat Treatment Superalloy f i n e wire heat treatment to achieve maximum strength i s accomplished i n an i n e r t or reducing atmosphere batch type furnace where temperature soaking time and cooling rate can be con t r o l l e d w i t h i n close l i m i t s For many of the superalloys the aging or p r e c i p i t a t i o n strengthening is of long duration (several hours) and requires close a t t e n t i o n to cooling rates from one temperature to another Some superalloys are very d i f f i c u l t to heat t r e a t without formation of a t i g h t l y adhering very t h i n oxide f i l m A ctually t h i s f i l m Is not considered detrimental to f a b r i c a t i o n or per formance of the fi n e wire herein described Should absolute freedom from an oxide f i l m be required i t is probable that the normal advances i n the state of the a r t w i l l provide for t h i s c a p a b i l i t y at the designated time period Most fin e wire manufacturers today claim to have the batch type heat t r e a t i n g f a c i l i t y needed to obtain maximum response from the p r e c i p i t a t i o n heat treatment Handling techniques appear to be adequate as does the uniformity of response to the aging cycle even for the large diameter strand indicated (0 24 i n and weighing up to 40 lbs ) No manufacturing development i s needed for batch heat treatment for the r e l a t i v e l y short lengths indicated (up to 200 f t ) Continuous'Strand Heat Treatment Duplex heat treatments i e dropping from one temperature to another at a defined rate i s not ea s i l y achieved i n a continuous furnace Although t h i s Is not a serious matter optimum aging response may not be achieved A further complication arises from the fact that the true strength of the wire or strand at high temperatures is low and may easily break Handling of the f r a g i l e strands would thus be a c r i t i c a l problem I t appears to be the general opinion of those engaged i n the manufacture and heat treatment of f i n e wire that a continuous process o f f e r s no advantage over the batch process and unless there are compelling reasons for doing so t h i s process i s not a t t r a c t i v e ALTERNATE PROCESSES NONE Code
92- TITLE ~ HANDLING METAL FOILS SHEETS AND EASILY DAMAGED LARGE VEHICLE ASSEMBLIES CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT E f f i c i e n t handling of large q u a n t i t i e s of metal f o i l s i s required avoiding contamination and damage throughout f a b r i c a t i o n and assembly operations The f o i l s anticipated are in t h i c k nesses 0 001 to 0 005 inch with widths up to 4 f t Foils and sheet may be clad or coated with rorrosion protective materials which are susceptible to damage Very l i g h t gauge f o i l s for multilayer r e f l e c t i v e thermal i n s u l a t i o n for cryogenic propellant tanks would be d i f f i c u l t to handle in large blankets on compound contours Many applications require stringent cleanliness control to maintain o p t i c a l or thermal properties for fuel/p r o p e l l a n t compatablllty Handling and f i x t u r i n g of sheets and assemblies must provide accurate positioning and freedom from dis t o r t i o n and damage Large assemblies are anticipated spacecraft h u l l s up to 20 f t x AO f t t o r r o i d a l tanks up to 80 f t dia antennae up to 60 f t dia wit h minimum weight for these large structures AARP REFERENCES E C h n r l . 211 B C h n r t . 95b 107a 111a b P&FVPS Charts APPLICABLE PROCESS Code SEE STATE OF THE ART ASSESSMENT BELOW STATE O F THE ART ASSESSMENT At the present time there appear to be no completely s a t i s f a c t o r y methods for handling of f o i l e i ther i n c o i l s or as uncoiled very l i g h t gauge s t r i p i n large sizes Some of the d i f f i c u l t i e s leading to damage are (a) gauges too t h i n for use of vacuum handling (b) d i s t o r t i o n from clamping (c) very susceptible to damage from chips d i r t (d) moisture entrapment i n c o i l g iving d i s c o l o r a t i o n and contamination (e) d i s t o r t i o n and residues from tape or abrasion protec t i v e f i l m removal ( f ) kinking w r i n k l i n g canning reverse curvature i n c o i l There are techniques which can be employed for s p e c i f i c problems as they are encountered and normal state of tt a r t advances for these when problems arise are considered adequate These techniques nclude (a) electromagnets for magnetic all o y s (b) vacuum l i f t i n g f i x t u r e s (c) soluble protec ti v e coatings (d) a i r tables (e) s l a t conveyers (rubber) ( f ) removable backing laminates and disposable pressure sensitive tapes and (g) handling f o i l s as far as possible in c o i l form Since problems vary widely with the sp e c i f i c intended use i t is suggested that any e f f o r t to expedite advances in techniques be made a part of a component development program In handling sheets and assemblies a t t e n t i o n must be given to p ovlslon and location of pick up tabs or extra t r i m for handling use of i n f l a t a b l e boots in r l g i d i z i n g f i x t u r e s vacuum h o i s t i n g of assemblies and i n t e r n a l pressurization of assemblies for s t i f f e n i n g Specific systems development programs such as the Atlas booster (a monocoque structure 10 f t dia x 80 f t long fabricated from sheet 0 010 to 0 030 inches t h i c k ) have used techniques suited to the s p e c i f i c handling and transport problems involved In some cases handling f i x t u r e s may have to r e s i s t very stringent environmental conditions when the component or assembly must undergo thermal treatment r a d i a t i o n chemical cleaning propellant system checkout environment simulation v i b r a t i o n or functional r e l i a b i l i t y t e s t i n g or c a l i b r a t i o n Manufacturing development e f f o r t is not recommended separately from component development but the necessary emphasis should be given to handling i n such programs CRITICAL ? C3 . b NONE ALTERNATE PROCESSES NONE Code
TITLE CASTING OF LARGE COMPLEX VANADIUM-BASE ALLOYS -93- CLOSE TOLERANCE CHROMIUM AND CHART N O ^ PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Chromium base and vanadium base alloys are considered as alternate materials to p r e c i p i t a t i o n strengthened and dispersion strengthened n i c k e l base alloys for use up to 2000 F for various airframe components The upper range may exceed the c a p a b i l i t i e s of the nickel-base al l o y s generating a requirement for an alternate material I n t h i s case components would be f i t t i n g s for b u i l t up i n t e r n a l structure r i g i d substructures and vanes for turbofan VTOL thrust vector c o n t r o l Configurations suggest close tolerance castings as suitable product forms Dimensional requirements for castings vary from three feet to s i x feet as the maximum dimension w i t h w a l l thickness down to 0 020 inches Sizes vary from 50 to 200 pounds Joining repair welding and mechanical fastening may be required Casting surfaces must be suitable for the a p p l i c a t i o n of oxidation r e s i s t a n t coatings AARP REFERENCES F r h-rf. 10. 47, 80 B Charts '* 31c 42c PAFVP<; rhnr t . APPLICABLE PROCESS SKULL MELTING AND CASTING INTO CENTRIFUGAL MOLDS 1 01 1 02 Code 12 07 STATE O F THE ART ASSESSMENT Chromium Base Alloys Chromium a l l o y castings have not been investigated to any appreciable extent except for l i m i t e d laboratory research studies A few small turbine castings have been made Castings lack strength and d u c t i l i t y The chromium vapors are highly v o l a t i l e and i n t e r f e r e w i t h arc s t a b i l i t y High p u r i t y chromium w i t h low oxygen has been alloyed w i t h Fe and Ni for sheet and plate studies but a l l o y castings have not been made successfully Mold material reactions have prohibited induction melting The usual casting problems would have to be solved i f a casting program were undertaken such as close tolerance c o n t r o l i n t h i n wall sections control of surface f i n i s h prevention of contamination by preventing reactions between the mold materials and the highly reactive molten metal development of suitable melting pouring and feeding practices and furnace designs including providing adequate power for melting c o n t r o l of arc s t a b i l i t y and develop ment of d i r e c t i o n a l s o l i d i f i c a t i o n technology to cont r o l grain size segregation and raicroporosity Vanadium Base A l l o y s Casting technology f o r vanadium i s similar to the technology for s k u l l melting and casting titanium Although somewhat similar to titanium vanad um has not been given the thorough a l l o y development as has titanium With the exception of V U V T i and V Fe systems the vanadium r i c h a l l o y systems have not been studied extensively As a pure metal vanadium has low strength and i s very susceptible to nitrogen oxygen and hydrogen erobrittlement when exposed to these gases above 575 F One hundred pound cylinders 14 inches diameter by 22 Inches long with 2 inch walls have been c e n t r i f u g a l l y cast as pure vanadium The p r o b a b i l i t y of meeting the strength requirements at 2000 F i s very low for V base alloys these requirements are (1) stress to rupture of 25 000 psi for 1000 hours and (2) a strength/density r a t i o of 100 000 inches Present c a p a b i l i t i e s of V base all o y s are less than h a l f these requirements Continued on next page ALTERNATE PROCESSES 'â¢lACHINING Code 5 01 00
94 CHART STATE OF THE ART ASSESSMENT, continued Vanadium a l l o y casting problems p a r a l l e l those of titanium and can be solved by the same approaches I t is expected that prevention of surface contamination may be a more d i f f i c u l t problem wi t h vanadium base alloys than with titanium base alloys and that arc s t a b i l i t y would be less In melting vanadium all o y s due (1) to the higher v o l a t i l i t y of vanadium and (2) to the reaction products formed from vanadium and the residual gases in the melting atmosphere CONCLUSION I t i s highly improbable that either Cr or V base alloys w i l l be used in any form much less castings for advanced airframe components i n the next 20 years The basic me t a l l u r g i c a l problems must f i r s t be solved with these alloys These problems are (1) lack of adequate strength and d u c t i l i t y for Cr base alloys and (2) lack of adequate high temperature strength for V base alloys No manufacturing development program for developing large t h i n w a l l castings to close tolerances should be undertaken for Cr and V base alloys at t h i s time
95- TITLE CHART PRIORITY EXTRUSION OF THIN WALLED COMPONENTS NO RELATED CAMR CHARTS AARP REFERENCES P r h n r f c 49, 80 R C h n K 11 15a b 16a b 31a b c d 42a b e 49 107a e 108c 109a 111a 122a b 123 124 PftFVP<l r h n r t . 125 134a b 136a c 138b APPLICABLE PROCESS j 2 03 02 Code EXTRUSION OR EXTRUSION PLUS DRAWING [ 2 03 07 MANUFACTURING REQUIREMENT To provide t y p i c a l airframe extruded shapes (tees angles channels H sections) with t h i n walls 0 040 to 0 080 inch + 10 percent thickness tolerance Cross sections would have a c i r cumscrlblng c i r c l e radius of from 1 to 2 inches w i t h lengths of from 6 feet to 40 feet Extruded sections are expected to have wide usage as f i t t i n g s s t i f f e n e r s edge members fo r supersonic hypersonic l i f t entry drag entry and spacecraft vehicles Materials Include beryllium high a l l o y and stainless steels t i t a n i u m alloys p r e c i p i t a t i o n and dispersion strengthened n i c k e l base and cobalt base superalloys columblum molybdenum tantalum tungsten and possibly chromium alloys STATE OF THE ART ASSESSMENT Extrusion and drawing techniques being developed under A i r Force sponsorship are directed to r e f r a c t o r y alloys t i t a n i u m ^beryllium dispersion strengthened n i c k e l alloys and too l steels I t i s expected that the techniques w i l l be applicable t o maraglng and stainless steel shapes Assuming that high q u a l i t y chromium extrusion b i l l e t s were available the techniques should permit the extrusion of simple shapes i n chromium alloys also Current A i r Force programs on high energy rate extrusion and hydrostatic extrusion plus r o l l forming w i l l enable consideration of these processes as alternates to d i r e c t extrusion With the introduction of higher strength superalloys the temperature range for extrusion can be expected to become very narrow This w i l l necessitate higher extrusion pressure capacity i n order to obtain the desired shapes Work Is c u r r e n t l y underway on A i r Force programs to develop t h i s capacity No specific a d d i t i o n a l extrusion programs are recommended at t h i s time However i t i s recommended that the r e s u l t s of current programs be examined against requirements such as described by AARP and ad d i t i o n a l development e f f o r t be devoted to necessary aspects The more general a p p l i c a b i l i t y of the extrusion plus subsequent metalworking techniques should be examined f o r other a l l o y s S i m i l a r l y developments i n the areas of die materials l u b r i c a t i o n studies extrusion container and press a u x i l i a r i e s should be related to requirements for complex shapes of the various alloys I f current programs indicate that contamination of extrusions remains a serious problem then development of a t o t a l l y enclosed atmosphere c o n t r o l system for the heating extruding and cooling stations i s recommended CRITICAL PROBLEMS ALTERNATE PROCESSES HIGH ENERGY RATE EXTRUSION (DYNAPAK) HYDROSTATIC EXTRUSION PLUS ROLL FORMING Code 2 03 03 2 03 07
96 TITLE BORON FILAMENT PRODUCTION OF QUANTITIES FOR PROTOTYPE COMPONENT FABRICATION CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT To make large q u a n t i t i e s of long close tolerance boron f i b e r s for filament winding Tolerance c o n t r o l should be i n the range of + 0 00015 inches to preclude voids overlapping and consequent loss of strength AARP REFERENCES E Charts 158 B rhnrt. 83c d P4FVPS C h a r t s . APPLICABLE PROCESS VAPOR DEPOSITION ON TUNGSTEN FILAMENT WITH BCl, H 3 "2 Code 1 05 01 STATE OF THE ART ASSESSMENT The only successful method at present i s vap BCI3 H2 reduction at 1900 2400 F Other promising (1200 1300 F) decomposition of B2H6 and the duo p i BCI3 H2 S i l i c a or quartz substrates appear promi plate simultaneous y) procedure which would increa the present approximately 10 ft/mln to 750 1000 f method appears to be 2 to 3 years away The devel fmciing l i g h t e r substrates than tungsten or elimin or deposition on tungsten filament from methods at present are the low temperature ating procedure f i r s t from B2H6 then from sing for a draw p l a t i n g (draw substrate and se the p o t e n t i a l speed of the process from t/min The successful development of t h i s opment of f i n e r filament is dependent upon ation of the requirement for a substrate No manufacturing development program is necessary since the c a p a b i l i t y now exists to manufacture q u a n t i t i e s of boron filament to the requirements established by the AARP However as process development continues through the supply of experimental q u a n t i t i e s some aspects should receive p a r t i c u l a r a t t e n t i o n A Vapor deposition Work should continue on vapor deposition w i t h emphasis on continuous filament tolerance c o n t r o l and substrate removal or s u b s t i t u t i o n of l i g h t e r substrate B A program should be developed to c o n t r o l surface contamination and eliminate prching C Melting and Drawing This method would eliminate the substrate and provide the p o t e n t i a l for long continuous filaments The p o t e n t i a l of t h i s method i s l i m i t e d by the tendency of boron to unite w i t h v i r t u a l l y a l l elements at the melting temperature D Raw material supply Emphasis must be continued on making a supply of high p u r i t y boron available E Work should continue to develop other types of filament materials such as carbon etc ALTERNATE PROCESSES 1 VAPOR DEPOSITION ON TUNGSTEN FILAMENT FROM B2H6 2 DUO CHEMICAL PLATING FROM B2H6 (low temp) and BCI3 H2 (higher temp) 3 DRAW PLATING ON CARBON COATED SILICA OR QUARTZ SUBSTRATE 4 MELT BORON AND DRAW FILAMENT WITH OR WITHOUT A SUBSTRATE Code 1 05 01 1 05 01 1 05 03 1 05 03
PROPOSED DEVELOPMENT PROGRAM No s p e c i f i c process development e f f o r t i s recommended to make available adequate q u a n t i t i e s of boron filament for prototype hardware development i n view of current A i r Force a c t i v i t y However a c o r o l l a r y program on non destructive inspection development Is proposed INSPECTION TECHNIQUES SUPPLEMEOTAL RECOMMENDATIONS INSPECTION REQUIREMENT OBJECTIVE BACKGROUND APPROACH In process and end item evaluation of production q u a n t i t i e s of boron filament for a p p l i c a t i o n to composite f a b r i c a t i o n To establish controls on f a b r i c a t i o n process and filament q u a l i t y evaluation w i t h respect to (a) diameter (b) flaw i n filaments and (c) properties of filaments Although a minimum e f f o r t has been made to apply NDT as process c o n t r o l and boron filament Inspection the e f f o r t has not been exhaustive (1) There is some e x i s t i n g f e e l i n g that filament q u a l i t y v a r i a b i l i t y becomes s t a t i s t i c a l l y less important when wound i n t o a composite This f e e l i n g has not been tested In d e t a i l however and could lead to inspection problems when time to solve them has slipped away The s p e c i f i c q u a n t i t a t i v e filament v a r i a b i l i t y problem must be defined f o r each filament/composite f a b r i c a t i o n process For fllam°nt diameter, measurement a capacitance gauge (CDD) is suggested because of the e l e c t r i c a l properties of boron I t i s a poor e l e c t r i c a l conductor or a lossy d i e l e c t r i c Eddy current techniques (CBA) have not been found r e a d i l y applicable but t h i s w i l l depend on filament properties as produced by various processes For flaws i n filaments, microradiography (BA) of composite specimens has been found useful provided the number of filament layers i s severely l i m i t e d (2 or 3 layers) Penetrants (ABB) have revealed filament s p l i t t i n g i n small composite specimens For filament properties, dynamic modulus techniques based on induced v i b r a t i o n s (DA) have shown t h e o r e t i c a l and p r a c t i c a l c a p a b i l i t y Equipment i s available for dynam c modulus determinations on the f l y for long filament lengths Although not studied i t Is expected that other filament mechanical properties can be correlated w i t h e l e c t r i c a l properties as gauged dynamically with d i e l e c t r i c or eddy current (CDD CBA) probes An NDT study should be i n i t i a t e d to operate concurrently w i t h e x i s t i n g or new filament f a b r i c a t i o n process development The important filament q u a l i t i e s should be defined i n terms of r e s u l t i n g composite q u a l i t y Composite f a i l u r e mechanisms c l e a r l y traceable to filament q u a l i t y should be separated from those associated w i t h prepreging and composite f a b r i c a t i o n These then become the target for NDT technique development for the filaments themselves Techniques should be selected/ optimized and calibra t e d f o r q u a n t i t a t i v e measurement of s i g n i f i c a n t a t t r i b u t e s The development program is summarized 1 Apply NDT to detect v a r i a b i l i t y i n boron filaments (thickness flaws properties) Continued on next page
98 APPROACH, continued CHART 2 Conduct f a i l u r e mechanism studies of composites fabricated from the NDT characterized filaments 3 Define s i g n i f i c a n t filament a t t r i b u t e s separate from non relevant filament variables 4 Select/optimize NDT for the s i g n i f i c a n t variables and e s t a b l i s h q u a n t i t a t i v e c a l i b r a t i o n s NDT should be developed as filament f a b r i c a t i o n process controls when possible 5 Write detailed NDT procedures Reference (1) Stinebring R C and Zurbrlck J R Property Determination and Process Control of Boron Filament Composites Using Non destructive Test Methods Proceedings of lOth National Symposium of Aerospace Material and Process Engineers San Diego C a l i f o r n i a November 10 1966
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS, AND AARP RATING FACTORS C A M R ctuicr. NUHBtK /t>3 /OS I06 BEF B-L20c Component 01 04 0 LEADING EDGE f o r B-3ii l i f t i n g r e - e n t r y v e h i c l e e a r t h o r b i t a l and lunar r e t u r n REF B-121C Component 08 01 0 HEAT SHIELD f o r B-3a vehlc l o o above BEP B-176b Component 08 07 0 HEAT SHIELD f o r C-3c abort/mlaolon r e - e n t r y encloaure l i f e aupport oyatem REF B-I45b Component 01 02 1 AERODYHAHIC LIFT & COimiOL STRUCTURE - FLEXIBLE (FLEX WING) f o r B-4a oarch landing syatcms t a n g e n t i a l and v e r t i c a l REF B-K9b Component 01 02 03 AEROOmHIC LIFT & CONTROL STRUCTURE - FLEXIBLB (FLEX DECELBRATOR) fo r B-6n eyotems above REF B-150b Component 01 02 4 AERODYNAMIC LIFT & CONTROL STRUCTURE - FLEXIBLE (FLEX ROTOR) f o r B-4o systems above REF Propulsion Requirement Base Metal Forma No 6 Component 23 01 0 FUEL CELL ELECTRODES f o r B-2a(l) spacecraft near space operations earth a a t e l l i t e f o r B-2a(2) space s t a t i o n , f o r B-2a(3) lunar v e h i c l e and B-2c spacecraft a h u t t l t . REF B-4 Component 06 03 0 VECTOR CONTROL & THRUST DEFLECTOR VANE f o r A-1 subaonlc long endurance a i r c r a f t chemical or nuclear fueled REF B-42a b c Component 01 01 2 AERODYNAMIC LIFT & CONTROL STRUCTURE - RIGID SUBSTRUCTURE f o r A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e s REF B-17o b B 18a b c d B 19a b Component 01 08 0 MAJOR STRUCTURAL FITTINGS (BULKHEAD ENGINE MOUNT WING SPARS HINGE) f o r A 2a and A-2b supoisonic hit^t- a l t i c u r i o long range chemical and nuclear fueled o l r c r a f t hypersonic c r u i s e high a l t i t u d e and low a l l i t u d e a i r c r a f t REF Propulsion Requirement M a t e r i a l Treatment No 1 Components 10 03 0 TURBOJET TURBINE VANES 10 06 0 TURBOJET AFTERBURNER COMBUSTION CHAMBER 10 07 0 TURBOJET AFTERBURNER FLAPS Cor A-2a supersonic high a l t i t u d e long ronge a i r c r a f t for A-2c supersonic t a c t i c a l V/STOL f i g h t e r and f o r B-la earth launch recoverable booster Components 12 03 0 TURBORAMJET TURBINE VANES 12 06 0 TURBORAMJET AFTERBURNER COMBUSTION CHAMBER 12 07 0 TURBORAMJET A r i E R B U R N E R FL/JS 12 11 0 TURBORAMJET DttFUSER LEADING EDGE 12 12 0 TURBORAMJET COMBUSTION CHAMBER f o r fl-2a supersonic high a l t i t u d e long range a i r c r a f t f o r A-3a(l) hypersonic c r u i s e high a l t i t u d e v e h i c l e and for B la earth launch rccovt.nble booster S Y S T E M PROaABI t IT t COMPONENT C R I T I C A U T V FREauCNCy OF Ravit IN S V S T E W \ D E S I G N A L T E R N A iS M A T C R I m S IMPUCATOH AARP RAW S C O R E S I t 1 6 3 3 2 1 I t s -r»TAL ff e z 2 3 & 0 31 ,*ff.o/,o, ,?^>, , s /z 3 & «e.6>7e, ,^3e , 1 S 6 0 Zt n / 2 3 V </ o 0 33 e/ etJ f4« , /t Z 2 3 0 3c /z n 3 0 33 <t / d 0 ze 0 ze ,13,0/0, ,g,2fi(3) /a 9 f 1 £ e 23,0/0 pZffCl} * / C e 0 zo 33 0/ 0 ,g ze^ 8 / O ,eit,<>3A f, , S / £ 3 3 3 C 0 so f / _ 6 0 23 /3 <7 3 3 J 0 J * .ofK<>.8,0, ,A 2t 9 C 6 0 zs C','\Z 3a, 8 IZ 6 3 0 za IP o,e,o ,4 â¢f3_. <£ 3 3 o t zn , /p, tfi q A, 3c It 11 6 * _ < _6 £ J C d> z</ _ Z - Z__ _ 3 3_ _ 3 _ 3 3 J â<? 0 to on 0 A ic io,oeo g (a IP g 7 c /a. It o3o fi Zo, , /z. « _ /2 0_Z3 0 2c 3 c o 0 Zo __9__ _6 3 3 e 0 Z7 /'â¢"^â¢^ A-^ . lIQl 0 ,/l â¢2A /« o 0 zfl It- 3 o 0 2</ n 9 9 3 t) Z1 /2,1,1,0, , /* 3 j r 0 J 7 /1,03,O, '>.'3fC'J, _ g _ 9 3 3 0 s< /laio, /I3^(0 6 3 o e 3 3 e 0 zc / 2 // o /) Sa6j 9 _ 3 __3 o 0 ^?
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS, AND AARP RATING FACTORS CAMR ciusr 107 lot no Continued from preceding page Components 13 01 0 RAHJET DIPPUSEa LBADIHG EDGE, 13 02 0 RAKJBT DIFPUSBR SKINS, and 13 03 0 HAKIET COMBUSTION CHAMBER f o r A-3aCl) hyperaonlc c r u i s e high a l t i t u d e v e h i c l e and B-la e a r t h launch recoverable booster Components lA 01 0 LIQUID ROCKET COMBUSTION CHAMBER and 14 02 0 LIQUID ROCKET MOTOR NOZZLE f o r B-la ea r t h launch recoverable booster and B-lb space launch earth o r b i t or lunar launch aystems Component 16 03 0 SCUD ROCKET NOZZLE f o r A-4b(l) s t r a t e g i c mobile ICBM m i s s i l e , f o r A-Ab(2} s t r a t e g i c s t o r a b l e ICBM m i s s i l e , f o r A-Ab(3) s t r a t e g i c space launched ICBM m i s s i l e , f o r A-Ab(6) strocegic r e - e n t r y m i s s i l e , f o r B-la earth launch recoverable booster, and f o r B - l b ( l ) space launch e a r t h o r b i t system REF Propulsion Requirement Base Hetal Forms No 1 Component 16 01 0 SOLID ROCKET MOTOR CHAMBER for B - l a ( l ) e a r t h launch recoverable booster and f o r B-lb(2) space launch lunar ayatera REF Propulsion Requirement Base Metal Forma Ho 3 Components 10 01 0 TURBOJET COMPRESSOR BLADES and 10 02 0 TURBOJET COMPRESSOR DISCS for A-2 supersonic high a U l t u d e long range a i r c r a f t and t a c t i c a l V-STOL a l r c r e f t and for A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e (maneuvering propulsion) REF B-148a Component 05 02 0 ENERGY ABSORBER (LANDING) iiS O B f o r B-6a e a r t h landing ayateras t a n g e n t i a l or v e r t i c a l ' ' ' ' ' ' ' Ì ' ' 1% 03 0, IZei o, ^2."7.; go/9, /3,o/o ff.ol.o. 14. e>2^ /</.'./o /4.°'3.o. /6oJo ft 03 o 10 Ol o ,/.o.<??<? REF Propulsion Requlremenc Base Mctol Form No 4 It 01 O Components 18 01 0 CASEOUS FLICUT POWER OEVICE TURBINE ⢠⢠' ' ⢠I DISC UITH lOTEGRAL BLADES and 22 02 0 CLOSED CYCLE TURBOELECTRIC FLIGHT POWER DEVICE TURBINE DISC WITH ft ? INTECRAL BLADES f o r e s s e n t i a l l y a l l f l i g h t v e h i c l e s k S Y S T E M PROBADILITI COMPONENr cRiTicAinr FREaUCNCV OF ravtT IN S Y S T E M D E S I G N A L T E R N A T O MATERIALS IMfUCAnOll A A R P RAW 3 C O K E S It e 4 I t & 3 3 1 1 I C S 6 q 'O T"»TAL S 8 ? 3 O 23 8 <i 3 S o 0 a3 6 3 3 o 0 S3 e f 3 3 o 0 23 ,«/«., e s 3 0 0 2 » , e 1 3 3 e 0 Z3 8 /z 3 0 0 -Zg e 3 3 a 0 Z3 g 9 3 3 o 0 3 3 .SJf^. . e / 2 3 o 0 26 J'A . 8 9 3 3 0 0 33 6 f 3 3 0 i> Z3 8 <9 3 3 0 0 _ 2 3 _ , S <f 3 3 o 0 2 J /2 9 2 3 o /Z 9 i 3 o >f 9 / 3 o 0 /7 n 9 / 3 e 0 3S 8 9 / 3 o i> 2/ IX f 3 e> 0 .Br'.o.. . 9 9 3 3 e 0 23 .8. iPfi). 9 Z. 3 o C 2i .8. 1.0.0) t _ .. 1 0 9 / o A 2. . 9 2__ & C 0 2, Ii. 9 z & 0 ss- ?!>. 9 z 3 C y 9 2 3 c /z 9 1 3 o 11 9 / e 0 32. /* 1 ___6 0 3Z
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS, AND AARP RATING FACTORS C A M R CHART /// /'3 / / r 116 111 i/e REP Propulolon Requirement Base Metal Forms No 5 Componento 10 03 0 TURBOJET TURfilNE VANES, 10 04 0 TURBOJET TURBIKB DISCS, and 10 05 0 TURBOJET TURBINE BUDBS f o r A-2 aupersonlc high a l t i t u d e long range a i r c r a f t and t a c t i c a l V/STOL f i g h t e r , and f o r A-3b hyperaonlc boost g l i d e straceglc or t a c t i c a l v e h i c l e (maneuvering pr o p u l s i o n ) Componenti 10 07 0 TURBOJET APTERBURNBR FLAPS f o r A-2 supersonic a i r c r a f t as above Components 11 04 0 TURBOROCKKT TURBINE DISCS and l l 05 0 TURBOROCKET TURBINE BLADES f o r A-3a hyper- sonic c r u i s e high a l t i t u d e or low a l t i t u d e v e h i c l e and A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e (maneuvering propulsion) REF B-20o,b Component OS.OJ.O RADIATION SHIELD (NUCLEAR AND SPACE) f o r A-2 supersonic high a l t i t u d e long range a i r c r a f t REF B-20a,b Component 08 03 0 RADIATION SHIELD (NUCLEAR AND SPACE) f o r A-2 supersonic high a l t i t u d e long range a i r c r a f t REF B-146 component 01 02 2 AERODYNAMIC LIFT & COOTROL STRXTURE - FLEXIBLE (SHROUD LINES) f o r B-4a ea r t h landing systems t a n g e n t i a l or v e r t i c a l REF B-li8b 153a,b Component 05 02 0 ENERC^ ABSORBER (LANDING) f o r B-4a ea r t h landing system t a n g e n t i a l or v e r t i c a l and B-4b space landing system REF B-95b Component 02 04 0 PRESSURE VESSEL (TORROIDAL TANK) for B-lb space launch systems REF B-1070 Componenc 02 01 0 SPACECRAFT HULL f o r B-2a Spacecraft near space op e r s t l o n s , earth s a t e l l i t e (ipacc scntlon or lunar v e h i c l e REF B-lUo b Components 06 05 0/07 01 0 SOLAR COLLtCTOR & ANTENNA f o r B 2a spacecraft as above REF B-148b 153a b Component 05 02 0 ENERGY ABSORBER (LANDING) f o r B-4a ea r t h l a n d i n g s y s t e m t a n g e n t i a l or v c r t L c a l and B-f'tb space l a n d i n g s y s t e m s REF B-4 Component 06 03 0 VECTOR COOTROL & THRUST DEFLECTOR VANES f o r A-1 subsonic a i r c r a f t long endurance REF B-31b c 42b c Component 01 01 2 AERODYNAMIC LIFT i CONTROL STRUCTURE - RIGID SUBSTRUCTURE for A-3a(l) hypersonic c r u i s e v e h i c l e high a l t i t u d e , and fo r A-3a(,2) hypersonic cruise v e h i c l e low a l t i t u d e f o r A-3b h>pctsonlc boost g l i d e v e h i c l e s s t r a t e g i c and t a c t i c a l ll I,0,n3,o, ,4 ^ , , S Y S T E M P R O B A B I L i n COMPOHENr C R I T l C A U T f FREaUCNCy OF KQMT IN S V S T E M D E S I G N A L T E R N A T E S MATCRIAIS IMPUCATIOII A A R P RAW S C O R E S 11 fe 3 3 1 1 1 C. 3 T"»TAL S 9 1 c q> 32 ey,o, ,/f| 2 , , / t <? 1 [> 32 ,/e.oS.o, 4 | , 1 / 0 3S ,/0,e,So, ,A,3,b. , Â¥ & i 0 2t ,10 oif o fi-sb ^ 6. 1 & i> 2/ 1 0 Zf / Z £ 1 G b a 8 /». / 0 2 f ."fi?^.<'. A^. , 1 a 0 ?/ f 6 9 / 0 2/ f 2 6 o /.el ^ .S'f^ . f t 9 /i /Z 2. 6 O / / 0 3/ n f 3 4 psoio gift, 1 3 4 t> 2/ c 2^cV^ B lb â¢3 (^ 33 /a / t tl _ _ ? _ 3 o 0 3e, 9 9 _5L_ 3 o 0 J3 0 2'i 05,"1,0 / z / V «S e2 o g £ 1 3 6 4 i> 2.1 0_3£1_ 0_ze 0 2S e / e o / o f l s 2 6 _ < j -§ e, 2. 6 _6 V __?_ 2 0 27
EXPLANATION OF C A M R REFERENCES TO S Y S T E M S , COMPONENTS, AND A A R P R A T I N G F A C T O R S CAMR CHAKT NUHBMt. U K . no I (23 R£F B 4 Component 06 03 0 VECTOR CONTROL h THRUST IKFLECTOR VANE f o r A 1 subsonic long endurance a l r c r a f c REF B 31c 62c Component 01 01 2 AERODlfNAMIC LIFT & COIfTROL STRUCTURE RIGID SUBSTRUCTURE f o r A 38 hyper onlc c r u i s e high or low a l t i t u d e v e h i c l e and A 3b hypersonic boost g l i d e v e h i c l e REF B 31a 42a Component 01 01 2 AERODYNAMIC LIFT & COOTROL STRUCTURE RIGID SUBSTRUCTURE for A 3a hyper B o n l c c r u i s e high or low a l t i t u d e v e h i c l e and A 3b hypersonic b o o s t g l i d e v e h i c l e REF B 31d Component 01 01 2 AERODYNAMIC LIFT & CONTROL STRUCTURE RIGID SUBSTRUCTURE for A 3a hyper sonic cr 1st high or low a l t i t u d e v e h l c l a REF B 16a b 49 122a b Component 01 01 1 AERODYNAMIC LIFT & CONTROL STRUCTURE RIGID SKIN for A 2 a per sonic high altLcuda Long rant^e a i r c r a f t and supersonic t a c t i c a l V/STOL t i g h t e r f o r A 3c hypersonic HTOL o r b i t a l v e h i c l e flnrt f or B l a l i f t ro e n t r y v e h i c l e REF B 136a b Component 01 01 1/01 01 2 AERODYNAMIC LIFT & CONTROL STRUCTURE RIGID SKIN/RIGID SUBSTRUCTURE for A 3o hypersonic c r u i s e high or low a l t i t u d e v e h i c l e A 3b hypcrnonlc boost g l l d t . v e h i c l e and fl 3a W i t re entry v e h i c l e REF B 11 Component 01 04 0 LEADING EDGE f o r A 2 super sonic h i ^ l i a l t i t u d e long range a i r c r a f t and t a c t i c a l V/STOL f i g h t e r REF B 107 Component 02 01 0 SPACECRAFT HULL for B 2a near spac opeiaclons spacecraft ( e a r t h s a t e l l i t e or apace s t a t i o n ) and P 2c spacecraft s h u t t l e (nan uv roh l ) REF B 108c 136a c Component 02 02 0 SPACECRAFT INTERKATION STRUOTURE £o B.2« nd V-3 y t mii aa above and B 3b drag c i t r y v e h i c l e KcF 3 109o Component 02 03 0 SPACECRAFT EXTERXAL TRlfCTI llE fo B 2 and B 2c y C ma ae bov ElEt H l*ia b Component 06 01 0 AIR INLETS & DUCTING fo A 2 8 pc onlc I r a f l s bova REF B l l l o Componen 06 05 0/07 01 0 SOLAR COLLECTOR STHLCTURE/ANTENNA for B 2o and B 2c systems as obovo REF B 124 Component 07 02 0 ELECTROMAGNETIC TRANS PARENCIES (RADOMES RADAR WINDOWS) for B 3a l i f t r e n t ry vehicles REF S 125 Component 07 03 0 OPTICAL TRANSPARENCIES (VISIRU IB UV) f o r B 3a l i f t re entry v e h i c l e s rtEF H U8b Component 09 02 0 SEAL f o r B 3b drag cry v L h l c l s REF Propulsion Requirement Bosc Metal Forms No 4 Components 2 03 08 RADIAL EXTRUSION/FORCING II 0/ 01 I 91. qi. I. Of o f t 0/ o»<<> oiOtq Otaio f>9et0 fifA'.o. ot eso ofole o9clc ii SYSTtM PROBABILITY COMPONENT CRITICAUTY FREaUCNCV OF mwit N sysTew> DESIGN ALTERNA a MATCRriuS IMmCATTOH A A R P RAW S C O R C S I t . 8 4 11 1 fe 1 3 1 1 S t 3 f, n a 8 <? / J e i> 3o B 6 s 0 96 / 3 6 0 23 $ s â¢3 0 z e Â¥ t 3 ^ 23 0 6 3 3 6 0 36 A , f t 9 7. C o 0 i9 0 n A i ' f , Â¥ (⢠1 c o â¢â¢^ 3A . 8 / i 3 C o 0 t9 n. 6 2. <, 0 0 i t A h . 9 1 c o i) 21 Â¥ f 6. o o 0 to 8 3 O 13 tt «. 6 0 t<i 17. 17- 3 3 o 0 3o fi-SLe e /2 3 3 0 B-Za. /a- & 3 3 o 0 i f PPf. e (, 3 o 0 TO n. 3 2 6 0 t) 23 /z 6 3 & o 0 27 e 3 3 i o /2 2 i o [^ 23 n 9 3 t e> 3o 8 9 3 6 o 8 i, 3 3 C o i> « 8 9 & 6 o 0 2£ It 3 2 e /Z *f f 6 & 0 9Â¥ /2. 9 / 6 6
EXPLANATION OF C A M R REFERENCES TO S Y S T E M S , COMPONENTS, AND A A R P R A T I N G F A C T O R S NUHSCK ns REF B 3 16a h 30b c i l b c Component 01 01 1 AERODYNAMIC LIFT i CONTHOL STRUCTURE - RIGID SKIN f o r A - l â¢ubflonlc loofc, ondurdnc« al c c c f t f c A-2 sup«itonlc high alclcudc long lango a i r c r a f t and Cactlc a l V/STOL f l g h t a r A-3fi hyporaonlc cruiao high or low a l t i t u d e v e h i c l e and A-3b hyparaonlc booat g l i d e vehlcloa scrategic or t o c c l c a l REF B-122b c Compononc 01 01 1/08 01 0 AERODYNAMIC LIFT & CONTROL STRUCTURE RIGID SKIM/KSAT SHIELD fo r B 3a l i f e r e - e n t r y v e h l c l a REF B 42b c Componont 01 01 2 AERODYNAMIC LIFT & CONTROL STRUCTlRt - RIGID SUBSTRUCTURE f o r A-3b hypersonic boose g l i d e vehicles REF B - I I Component 01 04 0 LEADING EDGE for A-l subsonic long endurance a i r c r a f t REF 11-92 Component 02 06 0 THRUST STRUCTURES f o r B l b ( 0 space lounch systems { e a r t h o r b i t launch) and B lb£2) spoce launch sysLem (lunar launch) REF 8-lSa,b 32b Conponent 06 01 0 AIR INLETS 6 DUCTING f o i A 1 subsonic long endurance a i r c r a f t and A 3a hypersonic c r u i s e v e h l c l o s RtF B nO« b Component 06 04 0 HEAT EXCHANGER (RADIATOR) for B 2a spacecraft near apace operations and B 2c opacocrafc s h u t t l e (maneuverable) h t l ll-5Ua Component 08 0] 0 HEAT SHIELD for A 3c hjperflonlc HTOL-orbital v e h i c l e tt-F B 20a Component 08 03 0 RADIATION SHIELD (NUCLEAR AND SPACE) for A 2a B u p e r a o n l e high a l t i t u d e (.heirUally f u e l n J and A 2b s u p e r s o n i c high a l t i t u d e n u c l e a r p o w e r e d a i r c r a f t REF B 1 J Conponent 01 07 0 PRESSURE VESSELS t TANKS 'or A 1 subsonic lon^, endurance a i r c r a f t R2F B-3 Component 01 01 1 AERODYNAMIC LIFT & COOTtOl STRLCTtniE - RICID SMN for A 1 a i r c r a f t i k SYBTtM PROSABIkin COMPONENT FREauCNCY or KUVtT IN svrrewi PESIQN MATCRIAIS IMPUCATION A A R P RAW S C O R E S I t . 8 It 1 6 3 S & 3 6 4 - 0 e £ t 6 0 i> 22 oy.e/y. ,4*., n. 9 Z 6, 0 0 Z9 e IZ Z S o 0 2S f f .o.'.f. A?^. f fZ 2 3 o l> At Af.o/J. .ff^^. e / £ / 3 e 0 34 fi tfi/.i, A^il. 4 9 z 3 o 0 /8 Af,eÂ¥,n At.. e 9 2 6 0 ^ ZC fifA*.«. A-M) n. ? / 6 0 e> 2v 9 / 6 0 0 30 $ 3 2 6 0 0 P*,o.'.o. AM . e 9 Z 6 o 0 2S /a fZ 1 6 o 0 3/ e tz / 6 o 0 :>9 OS. e/6 1 « tz / 6 o 0 33 9 & 0 0 Z9 68oJ_e A.24>. 9 z 6 c i> «/ PKot.e. A 1. . 8 6 2 3 6 0 2S 91. / . , 9 e 3 6 0 2S t> 1^ 6 1^ 0 0 * 0 0 1 1 1 1 1â1âi_i ⢠t> 0 i> . .. . 0
â¢105- PANEL ON FORMING Members L i a i s o n Mr Abraham H u r l i c h , Chairman Mr Max Guenther Mr Martin L Headman Mr John J Burke Mr A R Metzger Mr V a s i l P h i l i p c h u k Mr R i c h a r d Reynolds Mr J F Rudy S p e c i a l Advisor Mr W W Wood Vought Aeronautics D i v i s i o n LTV Aerospace Cor p o r a t i o n
-107- 2 2 FORMING A Summary of Problems and Recommendations With few exc e p t i o n s , the problems foreseen I n the forming of metal shapes f o r aerospace a p p l i c a t i o n s f a l l I nto two p r i n c i p a l c a t e g o r i e s The f i r s t category i s one of s i z e , both manned and unmanned aerospace v e h i c l e s of extremely l a r g e s i z e are e n v i s i o n e d , and these v e h i c l e s w i l l i n c o r p o r a t e v e r y l a r g e components i n v o l v i n g the forming of d e t a i l p a r t s much l a r g e r i n s i z e than h e r e t o f o r e attempted T h i s problem i s f u r t h e r complicated by the n e c e s s i t y f o r employing v e r y t h i n gauges of sheet m a t e r i a l f o r many of these l a r g e p a r t s The second category c o v e r s those forming problems d e a l i n g w i t h metals t h a t a r e e i t h e r higher m s t r e n g t h than those used i n previous aerospace a p p l i c a t i o n s , such as hig h e r s t r e n g t h a l l o y s t e e l s and beta t i t a n i u m a l l o y s , or metals r e q u i r i n g c o n s i d e r a b l y higher forming temperatures f o r f a b r i c a t i o n i n t o d e s i r e d shapes, such as b e r y l l i u m , s u p e r a l l o y s and r e f r a c t o r y metals I n many of the l a t t e r c a s e s , a d d i t i o n a l problems a r e introduced by the n e c e s s i t y f o r p r o t e c t - ing the metals from e x c e s s i v e o x i d a t i o n during forming at e l e v a t e d temperatures I n some i n s t a n c e s , both the problems of l a r g e s i z e and d i f f i c u l t - t o - w o r k metals a r e encountered i n the f a b r i c a t i o n of the same p a r t I n the proposed programs d e a l i n g w i t h the problems of forming v e r y l a r g e p a r t s , two approaches a r e g e n e r a l l y taken One approach d e a l s w i t h the study and e v a l u a t i o n of co m p e t i t i v e p r o c e s s e s f o r forming l a r g e p a r t s and i s concerned w i t h an a n a l y s i s of the f e a s i b i l i t y , p r a c t i c a b i l i t y and c o s t of designing and manufacturing the r e q u i r e d forming equipment The second approach i n v o l v e s experimental forming s t u d i e s m s c a l e model to develop b a s i c p r i n c i p l e s and t o o l i n g concepts These s t u d i e s a l s o i n v o l v e c o n s i d e r a t i o n of dimensional t o l e r a n c e s , f i t - up and handling problems The l a t t e r problem i s concerned both w i t h the v e r y l a r g e s i z e s and weights of some of the p a r t s and w i t h the f r a g i l i t y of l a r g e t h i n - s k i n n e d s t r u c t u r e s Many of the programs on the forming of l a r g e p a r t s , i n v o l v i n g both monocoque and s t i f f e n e d s t r u c t u r e s , contemplate e x p l o s i v e forming and s i z i n g as the p r e f e r r e d means of f a b r i c a t i o n While some of these p r o c e s s e s have a l r e a d y been reduced to production p r a c t i c e f o r the forming of lower s t r e n g t h aluminum a l l o y s , the a p p l i c a t i o n of these p r o c e s s e s to high s t r e n g t h t i t a n i u m a l l o y s , s t e e l s , b e r y l l i u m a l l o y s and s u p e r a l l o y s r e q u i r e s manufacturing development s t u d i e s Important c o n s i d e r a t i o n s i n the development of processes and equipment f o r the forming of metal shapes i n c l u d e the number of p a r t s to be produced and the degree to which the m a t e r i a l s of c o n s t r u c - t i o n , the dimensions and the shape of the p a r t s a r e defined I t would be extremely dangerous and w a s t e f u l to i n v e s t a l a r g e sum of money i n the production, f o r example, of a r o l l e x t r u s i o n or r i n g r o l l i n g machine fo r the forming of l a r g e c y l i n d e r s f o r rocket motor ca s e s and then f i n d
-108- that v e h i c l e design and m a t e r i a l changes have made the equipment o b s o l e t e because of l i m i t a t i o n s i n a v a i l a b l e power, s i z e or maximum he a t i n g temperatures L i k e w i s e , a l a r g e investment i n equipment may not be J u s t i f i e d i f only a few p a r t s are to be produced L e s s optimum production techniques such as the forming and J o i n i n g together of a l a r g e number of s m a l l e r s e c t i o n s ( w i t h attendant weight and r e l i a b i l i t y p e n a l t i e s ) may sometimes be r e q u i r e d on the b a s i s of economic c o n s i d e r a t i o n s The forming of small-to-moderate s i z e d p a r t s from r e f r a c t o r y metals and a l l o y s can be done by a v a r i e t y of means, s e v e r a l of which a r e recommended f o r study and development These means i n v o l v e molecular forming ( e l e c t r o f o r m i n g , vapor d e p o s i t i o n , plasma s p r a y i n g , e t c ) and high temperature f o r g i n g , s p i n n i n g and s t r e t c h forming The forming of bodies of r e v o l u t i o n by means of spinning and flow t u r n i n g a r e a l s o recommended The high temperature forming of r e a c t i v e and r e f r a c t o r y metals intr o d u c e s the n e c e s s i t y f o r i n e r t atmospheres and/or p r o t e c t i v e c o a t i n g s to prevent o x i d a t i o n and d e t e r i o r a t i o n of the base m a t e r i a l s during the fonnlng operations B Outlook A s i g n i f i c a n t new m a t e r i a l s development has been achieved s i n c e the completion of the study made by the Aerospace A p p l i c a - t i o n s Requirements Panel T h i s development c o n s i s t s of the h i g h s t r e n g t h , high modulus f i b e r strengthened composite m a t e r i a l s such as boron f i b e r r e i n f o r c e d p l a s t i c and metal m a t r i c composites These m a t e r i a l s o f f e r p o t e n t i a l weight sa v i n g s up to 50 percent i n a i r c r a f t and m i s s i l e s t r u c t u r e s w i t h consequent major performance I n c r e a s e s The A i r F o r c e has i n i t i a t e d , and i s supporting, major e f f o r t s to develop these m a t e r i a l s , to develop methods of s t r u c t u r a l a n a l y s i s and design of aerospace s t r u c t u r e s i n c o r p o r a t i n g high modulus f i b e r r e i n f o r c e d composites, and to b u i l d and ev a l u a t e prototype hardware components i n c o r p o r a t i n g these m a t e r i a l s How- ever, no i n t e n s i v e study has y e t been made t o ex p l o r e the f o r m a b l l i t y of metal m a t r i x composite m a t e r i a l s Among the composite m a t e r i a l s (both sheet and p l a t e ) t h a t can be advantageously used i n aerospace s t r u c t u r a l a p p l i c a t i o n s a r e aluminum and t i t a n i u m a l l o y m a t r i c e s r e i n f o r c e d w i t h boron or s i l i c o n c a r b i d e f i l a m e n t s , s t e e l or b e r y l l i u m w i r e , metal or metal oxide w h i s k e r s , e t c , and s u p e r a l l o y s r e i n f o r c e d w i t h r e f r a c t o r y metal or a l l o y w i r e The f o r m a b l l i t y of sheet and p l a t e metal m a t r i x composite m a t e r i a l s should be ev a l u a t e d and a program on t h i s s u b j e c t i s recommended The AARP p o s t u l a t e d , as p o s s i b l e a p p l i c a t i o n s of b e r y l l i u m sheet and p l a t e , the use of b e r y l l i u m and b e r y l l i u m a l l o y s i n the c o n s t r u c t i o n of p r e s s u r e v e s s e l s and cryo g e n i c p r o p e l l a n t tankage f o r lar g e aerospace s t r u c t u r e s While the a p p l i c a t i o n s of b e r y l l i u m as a i r - c r a f t and s p a c e c r a f t h u l l s k i n s and l a r g e antennas appear f e a s i b l e , the poor f r a c t u r e toughness of b e r y l l i u m p r e c l u d e s i t s use i n p r e s s u r e v e s s e l s , e s p e c i a l l y f o r low temperature s e r v i c e
109 TITLE FORMING LARGE BERYLLIUM COMPONENTS AND STIFFENER SECTIONS CHART NO ^ / 3 PRIORITY RELATED CAMR CHARTS 7ai MANUFACTURING REQUIREMENT 1 Form l a r g e c y l i n d r i c a l h u l l s e c t i o n (up t o 20 f o o t OD x Ì 0 f o o t l o n g ) from Be and Be a l l o y sheet and p l a t e m a t e r i a l and form s t r i n g e r s and s t x f f e n e r s f o r h u l l support elements 2 Form Be and Be a l l o y sandwich panels i n t o t u b i n g s e c t i o n s up t o 3 f o o t i n diameter and 2 inches i n w a l l t h i c k n e s s 2 Form Be and Be a l l o y s i n t o contoured shallow dishes w i t h v e r y c l o s e t o l e r a n c e s u r f a c e s Dishes are up t o 60 f o o t diameter and made from sheet and p l a t e 0 005 t o 0 250 inches t h i c k S t i f f e n e r s u p p o r t s t o be formed i n t o channels and other shapes A Same as 3 except t h a t contoured shallow d i s h i s made from sandwich c o n s t r u c t i o n w i t h honey comb or o t h e r shapes or core made from f o i l gauge Be and Be a l l o y s 5 Form Be and Be a l l o y sheet and p l a t e i n t o 10 f o o t diameter s p h e r i c a l p r e s s u r e v e s s e l s f o r upper stage s o l i d p r o p e l l a n t motors and cry o g e n i c p r o p e l l a n t s storage t o 150F AARP REFERENCES E Cha »s . B Charts. 212 107a 109b U l a b PSFVPS Chnrt. Forming No 1 APPLICABLE PROCESS HOT ROLL FORMING C y l i n d r i c a l s e c t i o n s HOT CREEP AND DRAPE FORMING shallow d i s h e s BRAKE FORMING. DIE FORMING s t i f f e n e r s e c t i o n s Code 3 03 07 3 03 06/ 3 03 21 3 03 01 / 3 05 00 STATE OF THE ART ASSESSMENT The AARP r e f e r e n c e s s t i p u l a t e v a l u e s o f (Ftu/p)RT r a n g i n g from 1 0 t o 1 6 x 10^ i n c h good f o r m a b i l i t y w e l d a b i l i t y and f o r some a p p l i c a t i o n s good r e s i s t a n c e t o b r i t t l e f r a c t u r e as e x e m p l i f i e d by a notched/unnotched t e n s i l e r a t i o i n excess o f 1 0 i n c h w i t h a notched specimen h a v i n g a Kt=6 The l a t t e r a p p l i c a t i o n s i n v o l v e pressure v e s s e l s f o r the storage o f cr y o g e n i c p r o p e l l a n t s However because o f the v e r y poor f r a c t u r e toughness o f b e r y l l i u m and b e r y l l i u m a l l o y s t h i s m a t e r i a l i s d e f i n i t e l y not recommended f o r use i n pressure v e s s e l a p p l i c a t i o n s e s p e c i a l l y f o r sub zero temperature use ( M a n u f a c t u r i n g Requirement #5) The ot h e r a p p l i c a t i o n s h u l l s e c t i o n s s o l a r c o l l e c t o r s and antennas r e p r e s e n t reasonable a p p l i c a t i o n s f o r b e r y l l i u m While b e r y l l i u m sheet and p l a t e m a t e r i a l can meet the lower end o f the above s t r e n g t h range the h i g h end i s beyond c u r r e n t c a p a b i l i t i e s and i n d i c a t e s the need f o r f u r t h e r a l l o y and process development work At the pre s e n t time moderately l a r g e c y l i n d r i c a l and c o n i c a l s t r u c t u r e s w i t h mechani c a l l y f a s t e n e d angle s t l f f e n e r s have been f a b r i c a t e d from h o t foirmed b e r y l l i u m sheet S t r u c t u r e s up t o 6 f e e t m diameter have been made f o r Agena adapters and Minuteman spacers and guidance c o n t r o l compartments B e r y l l i u m sheet p l a t e and s t r i p have been hot formed a t temperatures between lOOF 1400F i n t o angles channels 2 s e c t i o n s and ot h e r shapes w h i l e U channels down t o 0 040 i n c h w a l l t h i c k n e s s have been extruded i n l e n g t h s up t o 40 f e e t Heated ceramic f o r m i n g d i e s have been s u c c e s s f u l l y employed i n bending b e r y l l i u m i n t o v a r i o u s s t r u c t u r a l shapes used as s t l f f e n e r s Recent work has demonstrated t h a t compound curved s k i n s o f b e r y l l i u m can be formed by a hot f o r m i n g o p e r a t i o n combining creep and s t r e t c h wrapping T h i s has however been accomplished o n l y on r e l a t i v e l y s m a l l pieces and a d d i t i o n a l development work i s r e q u i r e d on f o r m i n g compound c u r v a t u r e shapes Work has a l s o been s t a r t e d t o i n v e s t i g a t e the r o l l bonding o f s t i f f e n e d r i b sandwich s t r u c t u r e s ALTERNATE PROCESSES NONE Code
110 CRITICAL PROBLEMS CHART NO A / 3 1 Maximum s i z e o f Be sheet and p l a t e a v a i l a b l e i s a p p r o x i m a t e l y 40 Inches x 100 inches AARP r e f e r e n c e s i n d i c a t e requirement f o r s i z e s up t o 132 inches x 540 inches 2 Be and Be a l l o y s are not p r a c t i c a b l y weldable s t r u c t u r e s must be m e c h a n i c a l l y f a s t e n e d w i t h s t i f f e n e r segments b o l t e d or r i v e t e d t o s k i n s e c t i o n s 3 The b r l t t l e n e s s o f Be and Be a l l o y s and v a r i a b i l i t y i n the p r o p e r t i e s o f sheet and p l a t e p r o d u c t s are c o n t i n u i n g problems Surface c o n d i t i o n i s e x t r e m e l y c r i t i c a l w i t h r e s p e c t t o f a b r i c a t i o n processes 4 Ceramic d i e s are b r i t t l e and p r a c t i c a l l i m i t a t i o n s e x i s t i n m a n u f a c t u r i n g s u i t a b l e data f o r f o r m i n g l a r g e p a r t s 5 I t i s d i f f i c u l t t o c o n t r o l d i e and workplace temperatures i n f o r m i n g l a r g e p a r t s PROPOSED DEVELOPMENT PROGRAM OBJECTIVE I t IS recommended t h a t a comprehensive program be undertaken t o develop e n g i n e e r i n g and p r o d u c t i o n data on the f o r m a b l l i t y o f b e r y l l i u m a l l o y s Data are r e q u i r e d on the f o r m a b l l i t y l i m i t s and optimum processes f o r compound c u r v a t u r e forming, o f la r g e sheet s e c t i o n s and on the f o r m i n g o f complex c u r v a t u r e elements r e q u i r e d f o r s t r u c t u r a l s t i f f e n i n g components BACKGROUND While c o n s i d e r a b l e d a t a e x i s t on the f o r m i n g c h a r a c t e r i s t i c o f b e r y l l u m and b e r y l l i u m a l l o y s ( r e f e r e n c e NASA Tm X 53453 The F a b r i c a t i o n of B e r y l l i u m A l l o y s Volume I I Forming Techniques f o r B e r y l l i u m A l l o y s ) th e r e i s a l a c k o f s y s t e m a t i c e n g i n e e r i n g and p r o d u c t i o n data on f o r m a b l l i t y l i m i t s as f u n c t i o n s o f sheet t h i c k ness type o f f o r m i n g o p e r a t i o n e f f e c t o f s i z e o f p a r t s t o be formed and on the optimum f o r m i n g techniques f o r d i f f e r e n t o p e r a t i o n s While been s u c c e s s f u l l y used i n punch and d i e f o r m i n g s m a l l p a r t s p r a c t i c a l problems w i l l a r i s e m e x t r a p o l a t i n g t h i s process ceramic t o o l i n g has from b e r y l l i u m sheet t o l a r g e p a r t s APPROACH The proposed development program should i n c o r p o r a t e the f o l l o w i n g a A s y s t e m a t i c d e t e r m i n a t i o n o f minimum bend r a d i i as a f u n c t i o n o f sheet t h i c k ness along w i t h the d e t e r m i n a t i o n and o p t i m i z a t i o n o f the p r o d u c t i o n methods t o achieve v a r i o u s s i z e s and shapes o f s t i f f e n e r elements The problems a s s o c i a t e d w i t h e x t r a p o l a t i n g these methods t o the p r o d u c t i o n o f l a r g e angles channels Z s e c t i o n s e t c e s p e c i a l l y where compound c u r v a t u r e s are r e q u i r e d should be assessed b The fo r m i n g o f compound c u r v a t u r e b e r y l l i u m sheet by means o f hot creep and drape f o r m i n g or creep and s t r e t c h wrap f o r m i n g should be i n v e s t i g a t e d Methods and a p p r o p r i a t e t o o l i n g should be developed which c o u l d p r a c t i c a b l y be extended to the forming o f l a r g e compoind c u r v a t u r e sheet panels c The present punch and d i e method f o r f o r m i n g curved channels should be assessed f o r adequacy and l i m i t a t i o n s f o r a p p l i c a t i o n t o l a r g e p i e c e s Means f o r c l o s e temperature c o n t r o l o f l a r g e d i e s and problems a s s o c i a t e d w i t h l a r g e ceramic d i e s should be e v a l u a t e d d A d d i t i o n a l j o g g l i n g development work i s recommended A l t h o u g h the f e a s i b i l i t y o f j o g g l i n g channel e c t i o n s i s i n d i c a t d f u r t h e r i n v e s t i g a t i o n and evelopment o f the processes are r e q u i r e d The d e t e r m i n a t i o n o f f i r m t r a n s i t i o n l e n g t h s f o r a l l gauges o f m a t e r i a l and repr>-sentativo s i z e s o f s e c t i o n s the development o f exact c o n t r o l s the e s t a b l i s h m e n t o f r o u t i n e p r o d u c t i o n procedures and the design o f s u i t a b l e s t a i n l e s s s t e e l matched d i e set s have not y e t been accomplished e Methods f o r m i n i m i z i n g g a l l i n g and sur f a c e damage o f b e r y l l i u m and b e r y l l i u m a l l o y s d u r i n g hot f o r m i n g should be e v a l u a t e d and improved methods developed f I n v e s t i g a t i o n should be male of the a p p l i c a b i l i t y o f the r o l l bonding process f o r p r o d u c i n g b e r y l l i u m sandwich s t r u c t u r e s by us i n g f i l l e r m etals which can "Ì e leached out a f t e r f o r m i n g the sandwich i n t o c y l i n d r i c a l or h e m i s p h e r i c a l shapes
I l l PRIORITY RATING WORKSHEET CHART P R Q g R A M FACTORS PROf iRAM PBOBABILITV- OF SUCCESS ⢠LOW 2. ⢠MODERATE 5 "P< HICH 8 CRITICAL PROBLEMS TO BE S0CV6O a F E W / N O T TOO D I F F I C U L T Z S O M E / D I F F I C U L T 3 Q MANY/ VERV D I F F I C U L T 8 P R O C E S S G R O W T H P O T E N T I A L ⢠LITTLE O K U N D E F I N A B L E O «£CO&Hyt.k^\.t P O T E M T I A L 4 A P P L I C A T I O N S OTHER THAN AIR F O R C E ⢠NOME O SOME 4 D MANY 6 N E C E S S I T Y FOR AIR F O R C e F U N D I N O D LOW HieH i N t u s i e V / ^ c r H c e G o « r S F F C I T * X MeO«/»TE - Some E F f o t T OTHCe -SwatfES 0 ⢠e i t fKJsi^E A I R P O U C L FuMt>N<i L I K C L V vi. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIQH PROBABILITY FAIR. P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y VERY WKCW HI A H FAIR LOW F R E f l U E N C Y OF REQUIREMENT IN S V « T E M M «Re THAN 3 COMPei'ENTS Z 3 CAMPei^lENTS S I N f l L E COMPOweNT O e S l S N A L T E R M A T E S No ALTEBNATe RKtEBEEN ONE AUTeRMATe SEVEB.AL ALTERMATES M A T E R I A L S I M P L I C A r i O N NEW MATEfclflL P£Vtt«J>»l£»IT CeO V MATERIAL l M P « > V t M E W T R E a ' P NO P R o s L E M F o d t s e e M IZ 8 4 14 9 Q) 3 3 2 I 6 3 6 4 o CALCULATE PRIORITY STEP I STEP 2 STEP 3 0 RAW sco<!es F O R EACH COMPONENT IN TABLES AT t N D o r PAMEL R t p « t T WITH liAlO T O T \ L S ENTEREP M A T K16MT AARP RA>W SCOftCS ⢠⢠H i CIRCLE HIGHEST AARP )?AW S C O R E IN EACH OTHER SYSTEM C IRCLE NEXT HI<BM£ST IF WITHIN ^ POINTS OF TOP SCORB n s c o R e HidH LOW NUMSCR or SVSTEWS CIRCLE FREOUENCY DISTRIBUTION FACTOR f BELOWt NUMBECt. Of SiSretM I Z HIGH N U M & E R OF SYSTEMS 0 I 2 RMOttE 1 0 \ Z 1 4 1 1 1 3 1 2. 1 p = n « f = TOTAL= PRIORITY (D
TITLE FORMING OF METAL MATRIX FIBER STRENGTHENED COMPOSITE SHEET CHART NO PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Form shapes o f simple and compound c u r v a t u r e from h i g h modulus f i b e r r e i n f o r c e d m e t a l m a t r i x composite sheet m a t e r i a l s The m e t a l m a t r i x may be a l l o y s o f aluminum t i t a n i u m or n i c k e l r e i n f o r c e d w i t h h i g h s t r e n g t h h i g h modulus f i b e r s or w i r e s o f boron b e r y l l i u m s t e e l molybdenum s i l i c o n c a r b i d e e t c or wh i s k e r s o f metals or m e t a l c a r b i d e s or oxid e s The r e i n f o r c e m e n t f i b e r s may be u n l d l r e c t i o n a l l y p l i e d or successive p l i e s may be o r i e n t e d a t v a r i o u s angles AARP REFERENCES E Charts None B Charts None PSFVPS Charts. APPLICABLE PROCESS HYDRAULIC BULGE FORMING BRAKE BENDING EXPLOSION FORMING STRETCH FORMING Code 3 03 23 3 03 01 3 08 01 3 03 05 STATE OF THE ART ASSESSMENT A c o n s i d e r a b l e m a t e r i a l s development e f f o r t i s c u r r e n t l y underway under the sponsorship l a r g e l y o f the A i r Force aimed a t the p r o d u c t i o n and u t i l i z a t i o n i n aerospace v e h i c l e s o f h i g l s t r e n g t h / w e i g h t h i g h modulus p l a s t i c and meta l m a t r i x composites r e i n f o r c e d w i t h newly developed f i l a m e n t a r y m a t e r i a l s o f e x c e p t i o n a l l y h i g h s t r e n g t h s and e l a s t i c m o d u l i i I n the area o f meta l m a t r i x composites a t t e n t i o n i s being d i r e c t e d t o composites o f aluminum t i t a n i u m n i c k e l base and s u p e r a l l o y s r e i n f o r c e d w i t h boron f i l a m e n t s or f i n e w i r e s o f b e r y l l i u m s t e e l molybdenum e t c M e t a l l i c c a r b i d e or oxi d e f i l a m e n t s or whis k e r s are a l s o o f i n t e r e s t as the r e i n f o r c e m e n t m a t e r i a l s While the main e f f o r t t o date i s c e n t e r e d upon the development o f m a t e r i a l s having enhanced mechanical p r o p e r t i e s a s i g n i f i c a n t e f f o r t i s a l s o being d i r e c t e d towards the development o f d e s i g n p h i l o s o p h i e s and procedures f o r i n t r o d u c i n g composite m a t e r i a l s i n t o aerospace products such as a i r c r a f t wing and t a i l s u r f a c e s h e l i c o p t e r r o t o r blades a i r c r a f t engine blades e t c Most of the work t o date has I n v o l v e d p l a s t i c m a t r i x composite m a t e r i a l s wl i c h have been f o r t l i e most p a r t f a b r i c a t e d e i t h e r i n t o f l a t sheet or i n t o c y l i n d e r s or o t h e r stapes o f r e v o l u t i o n by f i l a m e n t w i n d i n g o f tapes M e t a l m a t r i x composite m a t e r i a l s have been produced p r i m a r i l y by d i f f u s i o n bonding o f sheet t o produce f l a t p r o d u c t s Work has a l s o been done on plasma s p r a y i n g the m a t r i x m a t e r i a l onto t h e f i l a m e n t a r y m a t e r i a l t h a t i s wound i n f l a t or curved shapes but the p r o p e r t i e s o f plasma sprayed composites are reduced as compared t o d i f f u s i o n bonded composite m a t e r i a l s The vapor d e p o s i t i o n and l i q u i d i n f i l t r a t i o n o f metals to produce f i b e r s t r e n g t h e n e d composites have a l s o r e c e i v e d some a t t e n t i o n and more work o f t h i s n a t u r e i s w a r r a n t e d L i t t l e work has been done t o i n v e s t i g a t e the f o r m a b i l i t y o f m e t a l m a t r i x f i b e r r e i n f o r c e d sheet m a t e r i a l s N o r t h American A v i a t i o n I n c has e x p e r i m e n t a l l y h y d r a u l i c a l l y bulge formed s m a l l p i e c e s o f b e r y l l i u m w i r e - r e I n f o r c e d aluminum sheet t o a r a d i u s o f a p p r o x i m a t e l y 10 f e e t While b e r y l l i u m w i r e has some d u c t i l i t y boron f i l a m e n t i s e x t r e m e l y b r i t t l e Cold drawn carbon and s t a i n l e s s s t e e l s and molybdenum w i r e a l s o e x h i b i t some d u c t i l i t y and should p e r m i t some degree o f f o r m a b i l i t y o f composite sheet m a t e r i a l s c o n t a i n i n g these r e i n f o r c e m e n t m a t e r l a l s ALTERNATE PROCESSES NONE Continued on next page Code
CHART H 3 STATE OF THE ART ASSESSMENT, c o n t i n u e d I n o r d e i Co e x p e d i t e the i n t r o d u c t i o n o f meta l m a t r i x composite m a t e r i a l s i n t o aerospace v e h i c l e s i t i s necessary t o conduct s y s t e m a t i c i n v e s t i g a t i o n s o f Che f o r m a b i l i t y o f these n a C e i i a l s as f u n c t i o n s o f m a t r i x and r e i n f o r c e m e n t m a t e r i a l s and Cheir r e s p e c t i v e volume and gcometi i c a l d i s t r i b u t i o n s CRITICAL PROBLEMS 1 Boion s i l i c o n c a r b i d e and o t h e r f i l a m e n t a r y and whisker m a t e r i a l s are ex t r e m e l y b r i t t l e 2 Metal raaCrix f i b e r r e i n f o r c e d composite m a t e r i a l s r e a d i l y d elaminate upon d e f o r m a t i o n 3 Non d e s t r u c t i v e t e s t i n g t o e v a l u a t e damage and d e g r a d a t i o n o f both m a t r i x and r e i n f o r c e ment maCerials r e q u i r e development PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To e v a l u a t e the f o r m a b i l i t y o f m e t a l m a t r i x f i b e r r e i n f o r c e d sheet m a t e r i a l s as f u n c t i o n s o f m a t r i x and r e i n f o r c e m e n t m a t e r i a l s and t h e i r r e s p e c t i v e volume and g e o m e t r i c a l d i s t r i b u t i o n s APPROACH I t IS recommended t h a t a s y s t e m a t i c i n v e s t i g a t i o n be made o f the f o r m a b i l i t y o f sheet m a t e r i a l o f the f o l l o w i n g types a Aluminum a l l o y m a t r i x w i t h 50 per c e n t by volume of boron f i l a m e n t w i t h a l l p l i e s o f f i l a m e n t u n i d i r e c t i o n a l l y o r i e n t e d b Aluminum a l l o y m a t r i x w i t h 50 pe r c e n t by volume o f boron f i l a m e n t w i t h a l t e r n a t e p l i e s o f f i l a m e n t o r i e n t e d a t 90° t o each o t h e r c Same as (a) b i t w i t h c o l d drawn s t e e l w i r e r e i n f o r c e m e n t d Same as (b) but w i t h c o l d drawn s t e e l w i r e r e i n f o r c e m e n t e N i c k e l base s u p e r a l l o y s m a t r i x w i t h 25 pe r c e n t by volume o f TZM molybdenum a l l o y w i r e r e i n f o r c e m e n t w i t h a l l p l i e s o f w i r e u n i d i r e c t i o n a l l y or i e n t e d f Same as (e) but w i t h a l t e r n a t e p l i e s o f w i r e o r i e n t e d a t 90° t o each o t h e r The f o r m a b i l i t y l i m i t s and c h a r a c t e r i s t i c s o f m a t e r i a l s (a) th r o u g h ( f ) when s u b j e c t e J t o h y d r a u l i c bulge f o r m i n g e x p l o s i o n f o r m i n g brake bending and s t r e t c h f o r m i n g should be e v a l u a t e d on specimens as s m a l l as p r a c t i c a b l e t o y i e l d r e a l i s t i c f o r m a b i l i t y data Among the f a c t o r s t o be e v a l u a t e d are 1 E f f e c t o f fo r m i n g temperature 2 Springback 3 E f f e c t o f f o r m i n g upon mechanical p r o p e r t i e s 4 Damage and d e g r a d a t i o n o f m a t r i x and r e i n f o r c e m e n t m a t e r i a l s An e v a l u a t i o n should be made o f the f a b r i c a b i l i t y o f h a t s e c t i o n s t i f f e n e r s made from u n i d i r e c t i o n a l l y p l i e d b o r o n - r e i n f o r c e d aluminum a l l o y m a t r i x composite m a t e r i a l w i t h f i b e r s o m i t t e d from the r e g i o n o f the bends INSPECTION TECHNIQUE SUPPLEMEWTAL RECOMMENDATION OBJECTIVE The o b j e c t i v e o f the i n s p e c t i o n and e v a l u a t i o n program would be t o determine i f and how much,damage had been done t o the m e t a l m a t r i x composite m the for m i n g process Continued on next page
CHART 1 1 4 - INSPECTION TECHNIQUE SUPPLEMEOTAL RECOMMENDATION, c o n t i n u e d APPROACH The f i r s t p a r t o f the proposed program must be concerned w i t h d e t e r m i n i n g why and how the v a r i o u s k i n d s o f meta l m a t r i x f i b e r s t r e n g t h e n e d composite sheets f a i l d u r i n g the f o r m i n g process For example i t must be determined i f the f a i l u r e i s d e l a m l n a t l o n b r e a k i n g o f f i l a m e n t s or o t h e r mechanisms A q u a l i t a t i v e e v a l u a t i o n o f the damage vs f o r m i n g process must be made Once the f a i l u r e mechanism i f determined the methods o f non d e s t r u c t i v e t e s t i n g t o be e v a l u a t e d or used can be determined I n the non d e s t r u c t i v e t e s t i n g development program i t i s suggested t h a t the f o l l o w i n g be co n s i d e r e d 1 X r a y laminography u s i n g image systems 2 S t e r e o r a d i o g r a p h y 3 Neutron r a d i o g r a p h y f o r boron f i l a m e n t m a t e r i a l 4 An u l t r a s o n i c t e c h n i q u e or tech n i q u e s f o r d e t e r m i n i n g a modulus of e l a s t i c i t y f o r these m a t e r i a l s 5 A c o u s t i c e m i s s i o n Considerable time and e f f o r t must be expended on the i n s p e c t i o n and e v a l u a t i o n development program and on the development o f adequate sta n d a r d s t o ge t m e a n i n g f u l and u s e f u l i n f o r m a t i o n
115 PRIORITY RATING WORKSHEET CHART PRQgRAM FACTORS P R 0 6 R A M P R O B A B I L I T Y O F S U C C E S S D LOW Z ⢠M O D E R A T E 5 X H I A H 8 C R I T I C A L P R O B L E M S T O B E S 0 L V 6 O Q F E W / N O T TOO D I F F U J U L T 7. ⢠f i g O M E / D I F F I C U L T S ⢠M A N Y / VERY DIFFICULT S P R O C E S S G R O W T H P O T E N T I A L D LITTLE OR UNDEFINABLE O yL KECoaNaABLE PorEMTIAL 4 A P P L I C A T I O N S O T H E R T H A N A I R F O R C E ⢠NONE O ⢠SOME n " R MANY S N E C E S S I T Y F O R AIR FORCe F U N 0 I N C 3 D l ow HieH mtustttV/cTHtft Gowr gpF c r H ySL. iMoDcaATE - sone EFFOILT OTHCK 'Sou«<!es e a e x c L U s i y e A IR Folicb F U M C K K ^ L I K C L V \I. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIQH P B O B A B l t r y 12 FAIR P R O B A B I L I T Y 8 LOW P R O B A B I L I T Y 4 COMPONENT C R I T l C A L I T Y VERV H I i - H I I H I A H 9 FAIR 6 L o w 3 FREOUENCV OF R E a U I R E M E N T IN S Y S T E M MfiRE THAN 3 COMPomeNTS 3 Z 3 COMPeUeuTS 2 SINGLE ^OMPeNENT I OeSISN A L T E R N A T E S No A L T E R N A T E R W E S E E N ONE A L T E R N A T e 6 S E V E ( 2 . A L ALTERMATEe 3 MATERIALS IMPLICATION N e w MATEi2.inL Devt:u>(>MeNT e c u o 6 M A T t R l A L i M P r t O V E M C N T R£ia C 4 No PROBLEM FoUeSCEkl O 0 e 33 R A W 5C04ZCS F O R EACM REFceEMAP CoMFONCtfT IN T A B L U A T E N D or PANEL RtP«tT W I T H I J A W T O T H L S E N T E R C P IM QvlMUAKV AT tZlSMT AARP RA^I SCOWS / » ^ f / a Y ^ \ \ 1 1 1 1 I I I ⢠⢠⢠⢠⢠⢠⢠⢠1 = CALCULATE PRIORITY S T E P I CIRCLE HIGHEST A A R P RAW S C O R E n : S T E P 2 IN EACH OTHER S V S T E M C I R C L E NEXT H I C M E S T S C O R E IF WITHIN N U M B E R OF 4 P O I N T S O F T O P S C O R E >3 t o w S T E P 3 C I R C L E N U M B E R OF SYSTEMS L o w P R E O U E N C Y DISTRIBUTION F A C T O R I 2. 3 OK Nxe-E B£LOWi 0 I 2 RMoet t 0 1 2 I 4 1 1 1 3 1 *f 1 z 1 *f 1 4 TOTAL PRIORITY
1 1 6 TITLE MOLECULAR FORMING OF REFRACTORY METALS AND ALLOYS CHART PRIORITY REUTBD CAMR CHARTSi MANUFACTURING REQUIREMENT Produce 6 inch t o 24 inch diameter hollow h e m i s p h e r i c a l or c o n i c a l shapes w i t h i n t e r n a l s t l f f e n e r s f o r nose s h e l l s t r u c t u r e s and C and D shaped leading edge members w i t h i n t e r n a l s t l f f e n e r s 6 inch t o 12 inch I n span 2 inch t o 6 inch chord and 1 in c h t o 3 inch nose r a d i i w i t h w a l l thicknesses up t o 0 040 inch M a t e r i a l s t o be r e f r a c t o r y metals and a l l o y s o f tantalum molybdenum columblum and tungsten Thickness t o l e r a n c e s + 0 010 Inch AARP REFERENCES E Cho \ 52j_ B Cho ts 28c 83 30c d 40c PSFVPS Charts. APPLICABLE PROCESS One of the f o l l o w i n g depending on end Item ELECTR0F0R.1ING VAPOR DEPOSITION PLASMA SPRAY or ELECTROPHORESIS Code 3 03 17 7 14 06 7 14 02 7 08 02 STATE OF THE ART ASSESSMENT E lec t i o f o r m i n f . Commercial processes are c u r r e n t l y a v a i l a b l e f o r e l e c t r o f o r m i n g shapes of tantalum colunbium molyldenura and tungsten metal from molten f l o r i d e baths w i t h b u i l d u p r a t e s o f 0 001 inch ro 0 008 inch/hr depending upon c o m p l e x i t y o f the p a r t s Ta p a r t s up t o a p p r o x i 1 cely 30 inch diameter and 34 inch hi(,h can be produced on a v a i l a b l e equipment Processes oie a l s o aevelopcd for e l e c t i o f o r m i n g b i n a r y Co W and quaternary Co W Ni Fe a l l o y s from aqueous s o l u t i o n " ; i n t o complex shapes such as double contoured nozzles and'hollow t u r l ine blades Considerable progress has been made i n the development of low m e l t i n g temperature n e C a l l i c mandrels and In non m e t a l l i c mandrel m a t e r i a l s such as gla s s r e i n f o r c e d p l a s t i c s poljamide and p o l y v m y l d i c h l o r ide S t r e s s r e l i e f and other thermal treatments have been developed t o improve the mechanical p r o p e r t i e s o f e l e c t r o f o r m s Vapor D e p o s i t i o n V por depo I t l o n o f W Ta Mo Cb and Che Cb IZr W Ta W Re and Cb T l V l l o y f om h a l i d e co poundb has been commerciall> developed D e p o s i t i o n o f r e f r a c t o r y metals at b i l d p r a t e o f 0 005 inch/min has been achieved and 0 040 inch thicknesses can be deposited i n approximately i i/2 h o i r s Tubing from 10 f e e t to 30 f e e t i n l e n g t h has been formed by vapor d e p o s i t i n g Ta and the Cb l ^ r a l l o y s Cones o f r e f r a c t o r y metals up t o 8 inch diameter have been s u c c e s s f u l l y vapor deposited Strengths comparable t o those o f the annealed metals and a l l o y s are developed Pla ma Spray Plasma s p r a y i n g of Be W Ta Mo and Cb i s a commercial process and has r e s u l t e d i n prod c t i o n o f cubing nose cone shapes and domes up to 6 Inch r a d i u s Be has been subsequently d'Ì n t f i e l t o 95 96 percent o f t h e o r e t i c a l d e n s i t y by vacuum s i n t e r i n g and Co 99 percent o f t h e o r e t i c a l l e n s i t y by gas pressure dens i f i c a t i o n W p a r t s f o r i o n engine casings c r u c i b l e s and domes nave 1een produced w i t h w a l l thicknesses i n the range o f 0 007 inch to 0 5 inch A l l o y s can be plasma sprayed by using a l l o y powders Reactive and r e f r a c t o r y metals are plasma s rayed m i n e r t atmospheres I t i s p o s s i b l e t o get good a l h e s i o n e s p e c i a l l y i f post processing Continued on next page ALTERNATE PROCESSES NONE Code
1 1 7 STATE OF THE ART ASSESSMENT, c o n t i n u e d CHART . ^ , gas p r e s s u r e d e n s i f i c a t i o n i s used between plasma sprayed m e t a l and s u b s t r a t e s o f the same m a t e r i a l used as s t i f f e n e r s e t c Tungsten p a r t s w i t h i n t e r n a l s t l f f e n e r s have been success- f u l l y plasma sprayed E l e c t r o p h o r e s i s Very l i t t l e work has been done on the e l e c t r o p h o r e t i c d e p o s i t i o n o f r e f r a c t o r y m e t a l s W and Mo have been d e p o s i t e d I n o x i d e f o r m on mandrels then hydrogen reduced t o the metal and s i n t e r e d t o d e n s i f y them Dep o s i t s are l i m i t e d t o 0 010 Inch 0 020 i n c h i n t h i c k n e s s Ta and Cb can be e l e c t r o p h o r e t i c a l l y d e p o s i t e d i n m e t a l form u s i n g p r o p r i e t a r y nonaqueous s o l u t i o n s J CRITICAL PROBLEMS E l e c t r o f o r m i n g 1 I n s o f a r as e l e c t r o f o r m i n g the u n a l l o y e d r e f r a c t o r y m e t a l s from m o l t e n f l u o r i d e baths i s concerned the t e c h n i c a l problems are n o t severe the main problem I s economic because of the h i g h c o s t o f t h i s process as compared t o a l t e r n a t i v e methods o f f a b r i c a t i o n o f p a r t s 2 While some success has been achieved i n e l e c t r o f o r m i n g Mo-W a l l o y s i n m o l t e n f l u o r i d e baths i t i s e x t r e m e l y d i f f i c u l t t o e l e c t r o f o r m r e f r a c t o r y m e t a l a l l o y s s i n c e the chemical com p o s i t i o n o f the d e p o s i t e d m e t a l I s I n f l u e n c e d by c u r r e n t d e n s i t y which may v a r y w i d e l y e s p e c i a l l y on the s u r f a c e o f complex shapes 3 Since e l e c t r o f o r m i n g f r o m m o l t e n s a l t baths i s done a t 1300 1600F mandrels must be made from copper i r o n n i c k e l or g r a p h i t e which are machined or leached away a f t e r the e l e c t r o f o r m i s d e p o s i t e d T h i s one time use o f mandrels adds t o c o s t o f process 4 E l e c t r o d e p o s i t i o n r a t e s are low r a n g i n g f r o m 0 0005 i n c h t o 0 0008 i n c h / h r b u i l d u p r e q u i r i n g l o n g time t o produce f i n i s h e d p a r t s 5 Sharp changes i n s e c t i o n and c o r n e r s r e s u l t i n planes o f weakness a t i n t e r s e c t i o n s o f g r a i n boundaries which develop p e r p e n d i c u l a r t o the s u r f a c e s b e i n g d e p o s i t e d upon C a r e f u l d e s i g n p r a c t i c e s and generous f i l l e t r a d i i can a l l e v i a t e t h i s problem Vapor D e p o s i t i o n 1 Mandrel m a t e r i a l s must c l o s e l y approximate t h e c o e f f i c i e n t o f expansion o f the vapor d e p o s i t e d m a t e r i a l s o t h e r w i s e the d e p o s i t e d m e t a l may c r a c k d u r i n g cooldown f r o m the d e p o s i t i o n temperatures 2 The d e p o s i t e d m e t a l o f t e n s t i c k s t o the mandrel m a t e r i a l and i t i s d i f f i c u l t t o separate them 3 Vapor d e p o s i t e d t u n g s t e n i s v e r y n o t c h b r i t t l e as d e p o s i t e d and may c r a c k b e f o r e i t i s t h e r m a l l y t r e a t e d t o r e l i e v e s t r e s s e s 4 Scale up e x p e r i m e n t a t i o n i s necessary t o produce l a r g e hemispheres and cones 5 S t i f f e n e r elements would have t o be made fr o m machined r i n g s or o t h e r s e c t i o n s i n s e r t e d I n t o mand e l and the memb ane s e c t i o n o f h e m i s p h e r i c a l s h e l l s vapor d e p o s i t e d o n t o the e t l f f e n e r s and mandrel While good adhesion i s o b t a i n a b l e between vapor d e p o s i t e d m e t a l and sub s t r a t e s o f Cb and Ta problems of poor adhesion may be expected w i t h W and Mo meta l and a l l o y s The s t i c k i n g o f d e p o s i t s t o mandrels w i l l p r o b a b l y be I n t e n s i f i e d n e c e s s i t a t i n g d e s t r u c t i v e removal of the mandrels 6 While some b i n a r y and multicomponent a l l o y s can c u r r e n t l y be vapor d e p o s i t e d a d d i t i o n a l development and r e s e a r c h i n t o h a l l d e c h e m i s t r y i s r e q u i r e d t o s u c c e s s f u l l y vapor d e p o s i t r e f r a c t o r y m e t a l a l l o y s o f p o t e n t i a l e n g i n e e r i n g i n t e r e s t Plasma Spray 1 The post p r o c e s s i n g o f plasma sprayed p a r t s I s v e r y c r i t i c a l s i n t e r i n g and gas pres s u r e d e n s i f i c a t i o n procedures must be developed and improved t o g e t b e t t e r mechanical p r o p e r t i e s 2 The s t r e n g t h s of plasma sprayed p a r t s may be o n l y 40 50 p e r c e n t o f t h a t o f the base m e t a l f a b r i c a t e d by c o n v e n t i o n a l means 3 D i s t o r t i o n o f p a r t s d u r i n g s i n t e r i n g i s a c r i t i c a l problem Continued on next page
1 1 8 C H A R T . ^ , N O ^01 CRITICAL PROBLEMS, c o n t i n u e d E l e c t r o p h o r e s i s 1 So l i t t l e work has been done i n t h i s area Chat Che c r i t i c a l problems areas are d i f f i c u l t t o d e f i n e a t pre s e n t However l i m i t a t i o n s on t h i c k n e s s o f d e p o s i t w h i c h can be made may be s e r i o u s as w e l l as l a c k o f I n f o r m a t i o n on l i q u i d s c o m p a t i b l e w i t h e l e c t r o p h o r e C l c d e p o s i t i o n of r e f r a c t o r y metals Shrinkage d u r i n g r e d u c t i o n o f o x i d e s and s i n t e r i n g would p r o b a b l y be severe problems PROPOSED DEVELOPMENT PROGRAM OBJECTIVE BACKGROUND APPROACH To evaluaCe the c o m p e t i t i v e methods o f m o l e c u l a r f o r m i n g o f r e f r a c t o r y m e t a l com I ponents t o s e l e c t optimum method or methods and develop them t o p r o d u c t i o n c a p a b i l i t j l . Of t h e f o u r processes o f m o l e c u l a r f o r m i n g e l e c t r o f o r m l n g i s t h e one whi c h has been most e x t e n s i v e l y i n v e s t i g a t e d and developed t o p r o d u c t i o n stages The e l e c t r o p h o r e t i c | process has been l e a s t developed and o f f e r s l e a s t promise as a u s e f u l process f o r f a b r i c a t i n g r e f r a c t o r y m e t a l and a l l o y components f o r nose cone and l e a d i n g edge shapes E l e c t r o f o r m l n g has s e v e r a l s e r i o u s drawbacks one o f Che most s i g n l f l c a n c I s Chat few i f any o f the a l l o y s o f e n g i n e e r i n g I n t e r e s t have been or can be e l e c t r o deposlCed by known te c h n i q u e s While a few r e f r a c t o r y m e t a l a l l o y s have been e l e c t r o f o r m e d from aqueous s o l u t i o n s most success has been a c h i e v e d w l c h e l e c C r o d e p o e i c i o n o f r e f r a c t o r y m e t a l s f r o m fused s a l t baChs on meCal or graphlCe mandrels While t h e vapor d e p o s i t i o n and plasma spray processes f o r f o r m i n g f r e e s t a n d i n g bodies o f r e f r a c t o r y meCals has noc undergone as InCensive developmenC as Che e l e c c r o f o r m l n g process these two processes have a l r e a d y demonstrated cons''derable p o t e n t i a l but a r e n o t economic a t t h i s time Both processes s u f f e r from low m a t e r i a l u t i l i z a t i o n and the l a c k o f s u f f i c i e n t process developmenC t o d e f i n e optimum t e c h niques I n a d d i t i o n mandrel removal i s a slow and c r i t i c a l o p e r a c l o n due Co Che f r a g i l e naCure o f che as deposiCed maCerial I n s u f f i c i e n t work has been done on post t h e r m a l t r e a t m e n t s t o s t r e s s r e l i e v e vapor deposlCed m a C e r i a l and on develop ment o f optimum s p r a y i n g and s i n t e r i n g p rocedures f o r a t t a i n i n g maximum m a t e r i a l p r o p e r t i e s i n plasma sprayed p a r t s A d i s t i n c t need e x i s t s f o r more fundamental work on f a c t o r s u n d e r l y i n g t h e e l e c t r o f o r m i n g vapor d e p o s i t i o n and plasma spray processes These I n c l u d e Che f o l l o w i n g areas 1 Research and developmenC i n the f i e l d o f h a l i d e c h e m i s t r y t o develop means f o r vapor d e p o s i t i o n o f mulcicomponenc a l l o y s o f che composiclons of e n g i n e e r i n g inCeresC 2 Research and development o f the hot gas pr e s s u r e d e n s l f I c a t l o n o f plasma sprayed r e f r a c c o r y meCals t o Improve Cheir mechanical p r o p e r t i e s 3 I n v e s t i g a t i o n o f the r o l e s o f p a r t i c l e s i z e s s i n t e r i n g v a r i a b l e s and mi c r o sCrucCure on Che mechanical p r o p e r t i e s o f plasma sprayed r e f r a c c o r y meCals 4 Research on aqueous non-aqueous and fused s a l e baCh composiclons and operaClng c o n d i t i o n s which would lead t o the e l e c t r o d e p o s i t i o n o f m u l t i component a l l o y s o f r e f r a c t o r y m e t a l s h a v i n g c o m p o s i t i o n s o f e n g i n e e r i n g I n t e r e s t 5 I n v e s t i g a t i o n o f the i n f l u e n c e o f i m p u r i t i e s m i c r o s c r u c C u r e and chermal creaCmenCs on che mechanical p r o p e r C i e s o f e l e c c r o f o r m e d r e f r a c c o r y meCals and a l l o y s 1 IC i s recommended t h a t an a n a l y s i s be made o f Che c a p a b i l i t i e s limiCaCionE and pocen C l a l o f the vapor d e p o s i t i o n and plasma spray processes f o r the f a b r i c a t i o n o f r e f r a c t o r y m e t a l and a l l o y shapes r e q u i r e d f o r aerospace a p p l i c a t i o n These processes have not been a d e q u a t e l y evaluaCed I n comparison Co Che e l e c C r o f o r m l n g process 2 As pare o f the a n a l y s i s o f the vapor d e p o s i t i o n and plasma s p r a y processes l i m i t e d programs should be e s t a b l i s h e d t o e v a l u a t e the mechanical p r o p e r t i e s o f Continued on nex t page
- 1 1 9 CHART PROPOSED DEVELOPMEWT PROGRAM, c o n t i n u e d a number o f r e f r a c t o r y m e t a l s and a l l o y s produced by these processes and i n v e s t i g a t e a number o f process parameters such as r a t e o f d e p o s i t i o n mandrel m a t e r i a l s and p o s t - d e p o s i t i o n t h e r m a l and mechanical t r e a t m e n t s 3 S e l e c t one or more p r o m i s i n g processes o f mo l e c u l a r f o r m i n g o f r e f r a c t o r y metals and a l l o y s f o r more I n t e n s i v e development by a more thorough i n v e s t i g a t i o n o f the process v a r i a b l e s INSPECTION TECHNIQUES SUPPLEMENTAL RECOMMENDATIONS OBJECTIVE P r o v i d e i n process c o n t r o l i n s p e c t i o n and e v a l u a t i o n o f o b j e c t s being m o l e c u l a r l y formed by e l e c t r o d e p o s i t l o n f r o m fused s a l t baths or by the a l t e r n a t e processes I f end i t e m i n s p e c t i o n I s s u f f i c i e n t t o meet the needs most o f the problems are w i t h i n the s t a t e o f the a r t and r e q u i r e o n l y c a l i b r a t i o n e f f o r t s However i f i n process c o n t r o l i s r e q u i r e d the f o l l o w i n g background and program approach apply BACKGROUND Chemical Homogeneity X r a d i a t i o n methods i n v o l v i n g t r a n s m i s s i o n / a t t e n u a t i o n (BBA) b a c k s c a t t e r (BBS) f l u o r e s c e n t (BCB) methods and e d d y - c u r r e n t methods (CBA) can be used s e p a r a t e l y or I n c o m b i n a t i o n t o e v a l u a t e c h e m i c a l homogeneity assuming a r e l a t i v e l y u n i f o r m d e n s i t y and a range o f atomic number o f t e n f o r the c o n s t i t u e n t elements These methods are w i t h i n the c u r r e n t SOA f o r an end i t e m i n s p e c t i o n but f o r i n process c o n t r o l e x t e n s i v e development w i l l be r e q u i r e d t o p e r m i t scanning of the o b j e c t d u r i n g f o r m i n g p a r t i c u l a r l y when the p a r t i s submerged I n a fused s a l t b a t h Surface Roughness. V i s u a l i n s p e c t i o n i s adequate t o e v a l u a t e s u r f a c e d u r i n g plasma spray or vapor d e p o s i t i o n but when submerged i n a b a t h f o r e l e c t r o d e p o s i t l o n or fo r m i n g by e l e c t r o p h o r e s i s o b s e r v a t i o n by the unaided eye I s denied Under these l i m i t i n g c o n d i t i o n s a te c h n i q u e employing an o p t i c a l system (AAB) and i n f r a r e d i l l u m i n a t i o n (ECA) having a wavelength t h a t can p e n e t r a t e the b a t h c o u l d be success f u l i n d e t e c t i n g uneven or modular g r o w t h i n time f o r c o r r e c t i v e a c t i o n An Image a m p l i f i e r w i t h an i n f r a r e d s e n s i t i v e image s u r f a c e i s conceived as the p r i m a r y i n s p e c t i o n u n i t assuming th e I n f r a r e d i l l u m i n a t i o n can be o f a d i f f e r e n t wavelength t h a n the t h e r m a l l y e m i t t e d r a d i a t i o n C r a c k i n g D e t e c t i o n o f c r a c k i n g i n m o l e c u l a r formed p a r t s a f t e r removal from the f o r m i n g environment I s w i t h i n the c u r r e n t SOA I n process d e t e c t i o n o f c r a c k i n g w i l l r e q u i r e development o f e d d y - c u r r e n t probe c o l l s t h a t can operate a t temperatures up t o 1600 F Temperature compensation may be accomplished by hav i n g e l o n g a t e d c o i l s d i f f e r e n t i a l l y connected and assembled as a r o s e t t e ar ay Bonding t o S t l f f e n e r s U l t r a s o n i c methods are r e q u i r e d t o e v a l u a t e bonding Depending on the m a t e r i a l s and c o n f i g u r a t i o n s p u l s e echo (DAA) t h r o u g h t r a n s m i s s i o n (DAB) o r resonance (DAC) t e c h n i q u e s can be used f o r end i t e m i n s p e c t i o n For i n process a p p l i c a t i o n i n the f o r m i n g environment i t w i l l be necessary t o develop u l t r a s o n i c probes t h a t can f u n c t i o n a t temperatures up t o 1600 F P o r o s i t y and D e n s i t y R a d i a t i o n gauging ( B E ) Induced u l t r a s o n i c v i b r a t i o n (DA) and e l e c t r o m a g n e t i c i n d u c t i o n (CB) t e c h n i q u e s are s e n s i t i v e t o t h i c k n e s s o f s e c t i o n d e n s i t y and c o m p o s i t i o n R a d i a t i o n a n a l y s i s t e c h n i q u e s (BD) are s e n s i t i v e t o c o m p o s i t i o n and c r y s t a l s t r u c t u r e so a c o m b i n a t i o n o f two or more o f these techniques can e s t a b l i s h b o t h d e n s i t y and p o r o s i t y Thickness R a d i a t i o n gauging can determine the mass o f m a t e r i a l d e p o s i t e d r e g a r d l e s s o f p o r o s i t y or d e n s i t y U l t r a s o n i c resonance can measure the t h i c k n e s s but o n l y a t h i g h f r a c t i o n s o f the t h e o r e t i c a l d e n s i t y E l e c t r i c a l methods w i l l I n d i c a t e a v a l u e combining p h y s i c a l t h i c k n e s s and d e n s i t y A c o m b i n a t i o n o f two techniques when p r o p e r l y c a l i b r a t e d and c o r r e l a t e d can g i v e t h i c k n e s s and d e n s i t y Continued on next page
CHART 120 INSPECTION TECHNIQUES SUPPLEMENTAL RECOMMENDATIONS, c o n t i n u e d G r a i n O r i e n t a t i o n and R e s i d u a l S t r e s s X r a y d i f f r a c t i o n t e c h n i q u e s are SOA f o r bot h g r a i n o r i e n t a t i o n and f o r magnitude d i r e c t i o n and s i g n o f r e s i d u a l s t r e s s P o r t a b l e equipment I s a v a i l a b l e but I s l i m i t e d t o o p e r a t i o n a t ambient c o n d i t i o n s E l e c t r o m a g n e t i c I n d u c t i o n t e c h n i q u e s have the p o t e n t i a l t o measure d i r e c t i o n and magnitude o f r e s i d u a l s t r e s s e s T h i s can be accomplished by d i f f e r e n t i a l l y c o u p l i n g e l o n g a t e d c o l l s o r i e n t e d m u t u a l l y a t r i g h t angles I n a c r o s s or t e e c o n f i g u r a t i o n These c o l l s a l s o w i l l be s e l f compensating f o r temperature C a l i b r a t i o n and c o r r e l a t i o n w i l l c o n s t i t u t e a major e f f o r t APPROACH The f i r s t development should s t u d y the i n t e r r e l a t i o n o f the a t t r i b u t e s r e q u i r e d t o c o n t r o l the conformance o f p a r t s w i t h the s i g n a l s produced i n each o f the e v a l u a t i o n t e c h n i q u e s To c h a r a c t e r i z e the o b j e c t , a t l e a s t as many t e c h n i q u e s must be a p p l i e d as t h e r e are a t t r i b u t e s , a n d each te c h n i q u e must be planned t o be most s e n s i t i v e t o one o f the a t t r i b u t e s w i t h i n i t s s p e c i f i e d l i m i t s T h i s development c o u l d be per formed a t ambient temperatures w i t h samples o f the c a n d i d a t e a l l o y formed by the ca n d i d a t e m o l e c u l a r methods some samples v a r y i n g one a t t r i b u t e o n l y and l a t e r samples have a r e a l i s t i c v a r i a t i o n o f a l l a t t r i b u t e s Methods o f c a l c u l a t i o n then can be developed t o g i v e the v a l u e s f o r the i n d i v i d u a l a t t r i b u t e s from the combined d a t a f r o m the s e v e r a l e v a l u a t i o n t e c h n i q u e s T h i s c a l i b r a t i o n s t u d y should be per formed r e g a r d l e s s o f whether the e v a l u a t i o n i s t o be an i n process c o n t r o l or an e v a l u a t i o n o f an i t e m a f t e r f o r m i n g The g r e a t e s t v a l u e o f i n s p e c t i o n and e v a l u a t i o n t e c h n i q u e s a p p l i e d t o m o l e c u l a r f o r m i n g i s gained i f the te c h n i q u e s are a r e a l t i m e e v a l u a t i o n T h i s g o a l w i l l not be a t t a i n e d by p r e s e n t s t a t e o f the a r t but w i l l r e q u i r e the development o f equipment t h a t can be used i n h o t fused s a l t baths I n p r o x i m i t y t o a plasma arc or i n the environment used f o r vapor d e p o s i t i o n The development e f f o r t s r e q u i r e d are r e p r e s e n t e d by but not l i m i t e d t o the f o l l o w i n g 1 Develop u l t r a s o n i c t r a n s d u c e r c r y s t a l s t h a t can ope r a t e a t temperatures up t o 1600 F or develop c o o l e d d e l a y l i n e s t o c o u p l e a c o l d t r a n s d u c e r t o a hot o b j e c t w i t h o u t a l o s s o f the i n t e l l i g e n c e i n the u l t r a s o n i c s i g n a l 2 Develop c o n t a c t i n g eddy c u r r e n t c o l l s I n s u l a t e d t o p e r m i t h i g h temperature use and temperature compensated t o a l l o w s t a b l e r e p r o d u c i b l e use a t e l e v a t e d temperature 3 Develop a d e v i c e t h a t can p e r f o r m an x r a y spectrum a n a l y s i s o f the s u r f a c e o f the o b j e c t d u r i n g f o r m i n g by the c a n d i d a t e m o l e c u l a r f o r m i n g method I f t h i s development can be accomplished f u r t h e r e x t e n s i o n t o d i f f r a c t i o n methods f o r measurement of r e s i d u a l s t r a i n can be made
121 PRIORITY RATING WORKSHEET CHART P R O f i R A M P A C T O R S . P R 0 6 R A M P R O B A B I L I T V O F S U C C E S S n L O W 2. ^ MODeRATE 5 ⢠Ht&U 8 C R I T I C A L P R O B L E M S TO B E S O L V E D ⢠F e > \ / N O T TOO D I F F U J U L T Z ⢠S O M E / D I F F I C U L T 3 â¢0i M A N Y / V E R Y D I F F I C U L T 8 P R O C E S S C R O W T H P O T E N T I A L ⢠L I T T L E OR U N D E F I N A B L E O Jt, f Z e e O f i N l l A B L E P O T E W T I A L + A P P L I C A T I O N S O T H E R T H A N AIR FORCE ⢠N O N E O a S O M E 4 X M A N Y e NECESSITY FOR AIR FORCe FUNDINQ n l o w HlfiM I«I»UST<IV/C7-Hefl GOMT E F F C l T f ^ MCDCKATE - SOME BrfotX OTMOU â¢Souatf fS S ⢠ttccujsive A lK F e A £ t F U M P N ^ U K C L V 12. NEED FACTORS S Y S T E M S P R O B A B I L I T Y H I Q H P B O B A B I L l T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y V E R Y H I C H HI<KH F A I R t o w F R E a U E N C y O F R E Q U I R E M E N T IN S Y S T E M MORE THAW 3 C O M P e H E M T S Z 3 C6MPeHe-HrS S I N G L E C O M P O N E N T D E S I G N A L T E R N A T E S N o A L T E R N A T E R w E B E E N ONE A L T E R N A T E S E V E B . A L A L T E R N A T E * M A T E R I A L S I M P L I C A T I O N N e w MATE( ! . | f lL P tveu)»> l> l tNT «e<» O M A T e B i A L i M P f t o v e M C W T B e a D NO P R o u L e M F o n c ^ e e K i IZ 8 I I 9 3 3 2 I <J 3 6 o CALCULATE PRIORITY STEP I STEP 2 STEP 3 CIRCLE IN fACH CfTHER SVST6M IF WITHIW 4 POIMTS 9 e 8 33 R A W s c o a e s F O R E A C H R E F c e e x r c D CoMrONCMT IN T A R c e S A T E N D O F P A N E L I Z t P O C T W I T H P A I O T O T A L S E N T E R C P I N <5UMiUAeV AT C l 6 M ~ S Y S T E M S HIGHEST AARP RAW S C O R E C IRCLE NEXT HIG!M£ST OF TOP S C O R t n i tow ^ N U M & E R OF S y s T E M S HldH CIRCLE FREQUENCY DISTRIBUUON FACTOR NUMBEIt. OP S y S T t M S H l S M I 2 . 3 O K Moee SCORE 8ELX>Wi N U M & E R O F S Y S T E M S L O W 0 I 2 R M o e t 1 0 c l 2 > 1 1 1 3 1 z. 1 *f 1 4 ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠A A R P RANN SCORCS ⢠TOTAL PRIORITY *
122 TITLE FORMING SUPERALLOY THIN SHEET INTO SMALL RADIUS SEOffiNTS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Form t h i n gauge p r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base s u p e r a l l o y s i n t o l e a d i n g edge components f r o m 2 f e e t t o 12 f e e t i n l e n g t h and 1 i n c h t o 3 inches r a d i i Sheet must be formed t o w i t h i n 0 003 i n c h on c o n t o u r Sheet t h i c k n e s s - 0 005 i n c h t o 0 060 i n c h + 5 p e r c e n t and A8 In c h t o 96 i n c h i n w i d t h AARP REFERENCES E Charts. B Charts. 19 11 PSFVPS Charts. APPLICABLE PROCESS STRETCH FORMING OR EXPLOSIVE FORMING Code 3 03 05 3 08 01 STATE OF THE ART ASSESSMENT S t r e t c h Forming The key re q u i r e m e n t s o f s t r e s s / d e n s i t y r a t i o o f 90 000 Inches a t an o p e r a t i n g temperature of 1200 F and the r m a l s t a b i l i t y f o r 30 000 hours a t t h i s temperature and s t r e s s can be met by the annealed I n c o n e l 718 a l l o y W i t h a d e n s i t y o f 0 296 l b s / i n ^ t h e s e r v i c e s t r e s s amounts t o a p p r o x i m a t e l y 26 500 p s i At 1200 F I n c o n e l 718 shows a creep r a t e o f 3 x 10 ^p e r c e n t / h r (0 17 creep a t 30 000 hours) However t h i s a l l o y w i l l n o t meet the s e r v i c e r e q u i r e m e n t s a t temperatures up t o 1800 F I t i s reasonable t o assume t h a t d u r i n g the n e x t 10 15 years Improvements i n p r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base s u p e r a l l o y s w i l l be a b l e t o extend s e r v i c e temperatures t o 1500-1600 F A l s o t h e newer d i s p e r s i o n s t r e n g t h e n e d N l and N l Or a l l o y s w i l l p r o b a b l y meet the s e r v i c e r e q u i r e m e n t s a t the h i g h e r temperatures I n c o n e l 718 has e x c e l l e n t f o r m a b i l i t y a t room temperature showing a u n i f o r m e l o n g a t i o n o f 33 p e r c e n t and a t o t a l e l o n g a t i o n o f 30 p e r c e n t I n a 2 I n c h gauge l e n g t h Leading edge segments having r a d i i i n the range o f 1 i n c h t o 3 i n c h should be s t r e t c h f o r m a b l e a t room temperature u s i n g annealed I n c o n e l 718 P a r t s up t o 12 f e e t I n l e n g t h can be r e a d i l y formed on a v a r i e t y o f s t r e t c h f o r m i n g equipment i n c l u d i n g the Sher i d a n and Erco s t r e t c h presses The d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s are rea s o n a b l y d u c t i l e a t room temperature and v e r y d u c t i l e a t m o d e r a t e l y e l e v a t e d temperatures I n view o f the c l o s e t o l e r a n c e s t i p u l a t e d a heated d i e may be r e q u i r e d i n which case a p o l i s h e d s t e e l d i e undercut i f necessary t o compensate f o r s p r i n g b a c k should s u f f i c e The use o f ceramic d i e s f o r s t r e t c h formed p a r t s i s o f t e n e l i m i n a t e d by p l a c i n g a t h i n sheet o f annealed s t e e l between the d i e and the m a t e r i a l b e i n g formed S t r e t c h f o r m i n g or e x p l o s i v e f o r m i n g o f I n c o n e l 718 and s i m i l a r n i c k e l base s u p e r a l l o y s or d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s t o l e a d i n g edge shapes i s b e l i e v e d p o s s i b l e e i t h e r by pr e s e n t t e c h n o l o g y or as the r e s u l t o f moderate and normal development over the time p e r i o d 1965 1975 The r e q u i r e m e n t f o r h o l d i n g dimensions and c o n t o u r s t o + 0 003 i n c h i s n o t con s i d e r e d r e a l i s t i c s i n c e t h i n gauge sheet can be r e a d i l y f i t t e d t o the honeycomb core f o r ALTERNATE PROCESSES NONE Continued on next page Code
123 CHART STATE OF THE ART ASSESSMENT, c o n t i n u e d bonding by e i t h e r b r a z i n g or w e l d i n g The development of su p p o r t t o o l i n g f o r h a n d l i n g and bonding the l e a d i n g edge segment t o the c o r e would a m e l i o r a t e d i m e n s i o n a l problems E x p l o s i v e Forming U shaped segments have been s u c c e s s f u l l y e x p l o s i v e formed from heat r e s i s t a n t a l l o y sheet and h e l d t o c l o s e t o l e r a n c e s a p p r o x i m a t e l y + 0 003 Inches I f the maintenance of t h i s t o l e r a n c e by s t r e t c h f o r m i n g I s a severe problem a c o m b i n a t i o n o f s t r e t c h f o r m i n g and e x p l o s i v e s i z i n g may p r o v i d e a s o l u t i o n I n a d d i t i o n e x p l o s i v e f o r m i n g by i t s e l f u s i n g charges o f a p p r o p r i a t e dimensions i s a process which I s r e a d i l y adaptable t o f o r m i n g l e a d i n g edge s e c t i o n s f r o m t h i n gauge n i c k e l base a l l o y sheet CRITICAL PROBLEMS 1 H o l d i n g d i m e n s i o n a l t o l e r a n c e s o f + 0 003 Inches on t h i n skinned formed p a r t s 2 Trimming t h i n gauge s t r e t c h formed l e a d i n g edge segments w i t h o u t d i s t o r t i o n PROPOSED DEVELOPMENT PROGRAM OBJECTIVE De.jelop f o r m i n g c a p a b i l i t y f o r t h i n gauge d i s p e r s i o n s t r e n g t h e n e d n i c k e l base s u p e r a l l o y s t o produce l e a d i n g edge segments having s m a l l r a d i i and c l o s e d i m e n s i o n a l t o l e r a n c e s BACKGROUND S t r e t c h f o r m i n g or e x p l o s i v e f o r m i n g o f I n c o n e l 718 and s i m i l a r n i c k e l base s u p e r a l l o y s t o r e q u i r e d shapes I s b e l i e v e d p o s s i b l e e i t h e r by p r e s e n t t e c h n o l o g y or as the r e s u l t o f moderate and normal development over the ti m e p e r i o d o f 1965 1975 However the f o r m a b i l l t y o f the newer d i s p e r s i o n s t r e n g t h e n e d N i and Ni Cr s u p e r a l l o y s has n o t been t h o r o u g h l y e v a l u a t e d Since such m a t e r i a l s may be r e q u i r e d t o meet the h i g h e r temperature r e q u i r e m e n t s a l i m i t e d program i s recommended The re q u i r e m e n t f o r h o l d i n g dimensions and c o n t o u r s on 0 003 Inches i s not con s i d e r e d r e a l i s t i c s i n c e t h i n gauge sheet can be r e a d i l y f i t t e d t o the honeycomb core f o r bonding by e i t h e r b r a z i n g or w e l d i n g The development o f support t o o l i n g f o r h a n d l i n g and bonding the l e a d i n g edge segment t o th e core would a m e l i o r a t e d i m e n s i o n a l problems APPROACH While i t i s not b e l i e v e d t h a t a m a n u f a c t u r i n g development prog am on f o r m i n g t h i n sheet i n t o s m a l l r a d i u s segments i s a b s o l u t e l y r e q u i r e d I t may be d e s i r a b l e t o i n i t i a t e a s m a l l program t o s t r e t c h form a t y p i c a l l e a d i n g edge component from a d i s p e r s i o n s t r e n g t h e n e d N i or N i Cr s u p e r a l l o y The component should be of a s i z e and geometry f a l l i n g w i t h i n the s t i p u l a t e d l i m i t s Contour t o l e r a n c e s would be checked a f t e r s t r e t c h f o r m i n g and e x p l o s i v e s i z i n g should be attempted I f the r e q u i r e d t o l e r a n c e o f + 0 003 i n c h cannot be a t t a i n e d by s t r e t c h f o r m i n g alone I f r e q u i r e d i n t e r m e d i a t e a n n e a l i n g steps should be attempted Trimming o f the formed segments should be accomplished t o e v a l u a t e the se r i o u s n e s s o f t h i s problem and the necessary development accomplished
124 PRIORITY RATING WORKSHEET CHART P R Q g R A M FACTOttS P R 0 6 R A M P R O B A B I L I T V O F S U C C E S S ⢠L O W Z ⢠MODERATe 5 X H I S H 8 CRITICAL P R O B L E M S TO B E S O L V E D X F E V V / N O T T O O D I F F I C U L T 2 ⢠9 0 M £ / 0 I F F ( C U L T 5 Q M A N Y / V E R Y D I F F I C U L T « PROCESS GROWTH POTENTIAL X L I T T L E O R U N D E F I N A D L E O ⢠f J e a o e N i i A B L E p o r e w T i A L 4 APPLICATIONS O T H E R THAN AIR FORCE ⢠N O N E O X S O M E 4 ⢠M A N Y 6 NECESSITY FOR AIR FORCE FUNDINca ⢠l a w HifiM iNtuSTaV/^CTHCA & o v r C F F O C T H MeociZATE - sme E F n c T o r H c e 'Seue iÌes e a txciix^ut A I R F»ftct F U M P M s U K C L W i t NEED FACTORS S Y S T E M S P R O B A B I L I T Y H I Q H P C O B A B I L i r Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y V E R Y H I C H F A I R L o w F R E Q U E N C Y O F R E Q U I R E M E N T IN S Y S T E M M A R E THAM 3 C O M P O ^ I E H T S Z 3 C A M m U E N r S S I N f l L E C O M P O N E N T D e S t & N A U T E R M A T e S No A L r e C N A T e R n E s E C N ONE A L T E R N A T E S E V E R A L A L T E R N A T E S M A T E R I A L S I M P L I C A T I O N NeM M A T E R I O L D c y L O ^ M E M T C C A o M A T E R I A L I M P O O V b M C N T e E a < D N o P R o a u E M F o n c ^ e e K i VL 9 I* VL 9 3 3 2 I <J 6 3 6 4 o CALCULATE PRIORITY 2Z R A W 5 C o « S F O R E A C M (t£r(.(LtU.eCD IN T A B L E S A T t w o o r P A N E L 1Jt<>0tT W I T H T J A W ToTrtLS E N T C R T P M ^ O M M A t V S Y S T E M S STEP I S T t P 2 CIRCLE HIGHEST AARP RAW S C O R E IN EACH OTHER SYSTEM C I R C L E NEXT HIGWEST SCORE IF WITHIW if POINTS OF TOP SCORE n N U M & E R O F S Y S T E M S HldH LOW A A R P RA>M SCORES STEP 3 CIRCLE N U M B E R O F S Y S T E M S lovt FREOUEVICY DISTRIBUTION FACTOR NUMQen. O P s v s r e M S Hi&ri I 2. 3 »K M » < ^ B E L O W i 2 RMOOE 1 0 t z » 4 1 1 t 3 1 H 1 z 1 *f 1 4 ⢠⢠] ⢠⢠[ ] ⢠⢠[ ! ⢠⢠[ ⢠c ⢠⢠⢠p = n . ' f = TOTAL= 2Z Z 3 _ PRIORITY -ff
125 TITLE FORMING COMPONENTS OF LARGL (up t o 50 f t diameLer) ROCKET MOTOR CASES OF STEEL AND TITANIUM ALLOYS CHART PRIORITY NO iLOi- JUL RELATED CAMR CHARTS /07, 'TO I MANUFACTURING REQUIREMENT F a b r i c a t e s o l i d p r o p e l l e n t r o c k e t motor case (.omponents o f s t e e l and t i t a n i u m a l l o y s 1 i n c h t o 3 Inches i n t h i c k n e s s w i t h s t a n d a r d t h i c k n e s s and l e n g t h t o l e r a n c e s DOMES End Cl o s u r e s Up t o 50 f t d i a H e m i s p h e r i c a l Up t o 10 f t d i a CYL BODIES Up CO 50 f t diameter 5: t o 160 f t l o n g Y RINGS Up t o 50 f t diam°cer AARP REFERENCES E Charts. B Charts. 148 83a PSFVPS Charts. Forming No 1 APPLICABLE PROCESS ROLL EXIRUSION ROLL FORMING (ALL PARTS) EXPLOSIVE FORMING (END CLOSURES AND HEMISPHERES) SHEAR FORMING (CYLINDRICAL BODIES) HOT SPINNING (END CLOSURES AND HEMISPHERES) RINC TOLLING (Y RINGS AND BLANKS FOR CYLINDRICAL BODIES) ROLL & WELD (Y RINGS CYLINDRICAL BODIES END CLOSURES 6, HEMISPHERES) 03 03 U/S°t)^ 08 01 19 14 02 C 03 07 /e 01 00 03 03 STATE OF THE ART ASSESSMENT R o l l E x t r u s i o n ((i-Vil Process) P r e s e n t c a p a b i l i t y i s l i m i t e d t o 160 i n c h max diameter and 240 i n c h max l e n g t h ^ i c h 3/4 i n c h max w a l l t h i c k n e s s Experience t o date has been l i m i t e d t o s t e e l and aluminum a l l o y c y l i n d e r body s e c t i o n s w i t h minor work on end c l o s u r e s P a r t s are produced which r e q u i r e no i n t e r n a l or e x t e r n a l s u r f a c e machining except a t attachment p o i n t s The p r e s e n t l y a v a i l a b l e r o l l e x t r u s i o n machine developed under an A i r Force program I s a d j u s t a b l e t o form c j l i n d r i c a l b odies from a p p r o x i m a t e l y 100 inches t o 160 inches i n diameter w i t h u n i f o r m w a l l t h i c k n e s s and c o u l d o p e r a t e a t temperatures up t o 900 F Enlarged s e c t i o n s f o r machining o f f l a n g e s f o r b o l t e d attachments or f o r weld r e i n f o r c e m e n t can be developed a t ends o f c y l i n d e r R o l l Forming ( L a d i s h Process) The L a d i s h Company Cudahy W co h developed p op e L a y o i l f o g equipment and process t e c h n i q u e s which have s u c c e s s f u l l y produced r i n g s jp t o a p p r o x i m a t e l y 22 f e e t diameter and 3 f e e t h i g h from the 200 grade maraging s t e e l s t a r t i n g from 26 000 l b i n g o t s T h i s process can produce end f l a n g e s as w e l l as i n t e g r a l s t i f f e n i n g r i n g s and a l s o wide v a r i a t i o n s i n w a l l t h i c k n e s s from one end o f a c y l i n d e r t o another Among ot h e r p r o d u c t s which have been produced on t h i s equipment are 120 i n c h diameter by 132 i n c h l o n g c y l i n d e r s from D6AC s t e e l w i t h i n t e g r a l 0 D and I D end f l a n g e s 156 i n c h diameter by 5 f o o t long c y l i n d e r s from 200 grade maraging s t e e l w i t h w a l l t h i c k n e s s v a r y i n g f r o m 1 1/2 i n c h c h i c k t o 0 119 i n c h t h i c k Continued on next page ALTERNATE PROCESSES NONE C o d e
CHART 126 STATE OF THE ART ASSESSMENT, c o n t i n u e d 120 i n c h diameter by 48 I n c h l o n g c y l i n d e r s f r o m 2014 aluminum a l l o y w i t h I n t e g r a l 0 D and I D c i r c u m f e r e n t i a l r i b s t i f f e n e r s E x p l o s i v e Forming E x p l o s i v e f o r m i n g has been used t o produce end c l o s u r e s o f l i g h t gauge m a t e r i a l up t o 30 f e e t i n d i a m e t e r T h i s appears t o be a p r o m i s i n g p r o d u c t i o n method f o r low p r o d u c t i o n r a t e s up t o say 12 p a r t s per year ARPA c o n t r a c t w i t h Martin-Denver and the U n i v e r s i t y o f Denver which i s c u r r e n t l y I n process should p r e s e n t a much more complete e v a l u a t i o n Shear Forming expensive t e l y 3/4 i n c h w a l l P a r t s iameter Heavy s e c t i o n s f o r c y l i n d e r I n s i d e diameter Hot S p i n n i n g P r e s e n t c a p a b i l i t y i s l i m i t e d t o 190 i n c h i n diameter and 4 i n c h i n t h i c k n e s s T h i s i s a hot f o r m i n g o p e r a t i o n and a c c o r d i n g l y the f i n i s h e d p a r t must be machined Hot s p i n n i n g was used to form the m a j o r i t y o f the end c l o s u r e blanks f o r the 120 i n c h s o l i d motors I t i s a proven p r o d u c t i o n method There appear t o be no t e c h n i c a l problems t o s c a l i n g up t o l a r g e r s i z e s Ring R o l l i n g P r e s e n t c a p a b i l i t y i s l i m i t e d t o 24 f e e t diameter 72 i n c h h e i g h t and 8 i n c h t h i c k n e s s P a r t s produced are f o r g l n g s which r e q u i r e machining t o produce f i n i s h e d p a r t T h i s i s a proven p r o d u c t i o n process f o r l a r g e r i n g s There appear t o be no t e c h n i c a l problems t o s c a l i n g up t o a l a r g e r diameter R o l l & Weld Prese n t c a p a b i l i t y f o r c y l i n d e r s i s i n excess o f 22 f e e t i n diameter i n t h i c k n e s s e s o f 1 i n c h Length o f s e c t i o n s i s l i m i t e d by w i d t h o f p l a t e a v a i l a b l e p r e s e n t l y l e s s than 200 inches P r e s e n t c a p a b i l i t y f o r Y Rings i s i n excess o f 22 f e e t i n diameter t h i c k n e s s e s t o 4 Inches Present c a p a b i l i t y f o r end c l o s u r e s or hemispheres i s 22 f e e t i n t h i c k n e s s o f 1 i n c h Case segments are f a b r i c a t e d from p l a t e s r o l l e d i n t o a r i n g and welded l o n g i t u d i n a l l y w i t h r e s p e c t t o the case Segments are then j o i n e d e i t h e r m e c h a n i c a l l y or by w e l d i n g t o form the c y l i n d r i c a l case End c l o s u r e s are f a b r i c a t e d from gore s e c t i o n s which are welded t o form the r e q u i r e d h e m i s p h e r i c a l or e l l i p t i c a l c o n f i g u r a t i o n CRITICAL PROBLEMS General 1 Size and weig h t o f raw m a t e r i a l needed f o r l a r g e c y l i n d r i c a l bodies g r e a t l y exceed p r e s e n t and f o r e s e e a b l e i n g o t s i z e s f o r b o t h s t e e l and t i t a n i u m Segmented c y l i n d e r d e s i g n would be necessary f o r the l a r g e r c y l i n d e r s 2 T r a n s p o r t a t i o n and h a n d l i n g o f v e r y l a r g e and heavy preforms and f i n i s h e d c y l i n d r i c a l s e c t i o n s pose c r i t i c a l problems R o l l E x t r u s i o n 1 C o n s t r u c t i o n o f a r o l l e x t r u s i o n f a c i l i t y w i t h the c a p a b i l i t y o f f o r m i n g 50 f o o t diameter c y l i n d r i c a l bodies would be v e r y expensive I t i s e s t i m a t e d t h a t the c o s t f o r such a f a c i l i t y t o produce s t e e l p a r t s would be on the o r d e r o f $25 x 10^ 2 R o l l e x t r u s i o n has not been used f o r t i t a n i u m a l l o y s T i t a n i u m must be heated t o tempera t u r e s i n the range o f 900 1200 F f o r r o l l e x t r u s i o n T h i s r e q u i r e m e n t c o m p l i c a t e s d e s i g n and would i n c r e a s e the c o s t o f the f a c i l i t y C ontinued on next page
127 CRITICAL PROBLEMS, c o n t i n u e d 3 Work on r o l l e x t r u s i o n o f hemispheres and c l o s u r e s has been v e r y r u d i m e n t a r y t o da e has n o t been f i r m l y e s t a b l i s h e d t h a t t h i s process i s p r a c t i c a l f o r these p r o d u c t s CHART I t Shear ForminR diameter 1 C o n s t r u c t i o n o f shear f o r m i n g f a c i l i t y w i t h c a p a b i l i t y o f f o r m i n g 50 f e e t d c y l i n d r i c a l bodies would be v e r y expensive e s t i m a t e d a t $20 x 10^ f o r s t e e l 2 I t would be necessary t o heat t i t a n i u m t o a p p r o x i m a t e l y 900 1200 F f o r shear f o r m i n g which c o m p l i c a t e s d e s i g n and o p e r a t i o n o f equipment 3 Manufacture o f mandrels f o r SO f e e t diameter bodies would p r e s e n t tremendous c r i t i c a l problems F o r g i n g machining and heat t r e a t i n g o f the segments would r e q u i r e equipment which has not y e t been b u i l t These blanks would have t o be produced Hot S p i n n i n g 1 C o n s t r u c t i o n o f a hot s p i n n i n g f a c i l i t y w i t h the c a p a b i l i t y o f f o r m i n g 50 f e e t diameter domes would be expensive I n a d d i t i o n l a r g e and expensive machine t o o l s would be r e q u i r e d tc produce the f i n i s h e d p a r t 2 Very l a r g e p l a t e s would be r e q u i r e d as b l a n k s by w e l d i n g l a r g e p l a t e s Ring R o l l i n g 1 C o n s t r u c t i o n o f a r i n g r o l l i n g f a c i l i t y w i t h the c a p a b i l i t y o f p r o d u c i n g 50 f e e t diameter r i n g s a t the a p p r o p r i a t e h e i g h t and t h i c k n e s s would be expensive I n a d d i t i o n l a r g e and expensive machine t o o l s would be r e q u i r e d t o produce f i n i s h e d Y r i n g s and f i n i s h machined blanks f o r e i t h e r shear f o r m i n g or r o l l e x t r u s i o n R o l l & Weld 1 As a r e s u l t o f the l i m i t s o f l e n g t h and w i d t h o f p l a t e m a t e r i a l an e x t e n s i v e amount o f w e l d i n g b o t h l o n g i t u d i n a l and c i r c u m f e r e n t i a l w i l l be r e q u i r e d t o f a b r i c a t e the case At l e a s t two and p r o b a b l y t h r e e l o n g i t u d i n a l welds would be r e q u i r e d f o r each segment PROPOSED DEVELOPMENT PROGRAM OBJECTIVE BACKGROUND To d e f i n e the work necessary t o e s t a b l i s h a f a b r i c a t i o n c a p a b i l i t y f o r the p r o d u c t i o n o f 50 f o o t diameter by 160 f e e t l e n g t h r o c k e t motor cases Because o f c o s t s i n v o l v e d problem i d e n t i f i c a t i o n and development o f the f a b r i c a t i o n c a p a b i l i t y i s proposed but not the manufacture o f p r o t o t y p e hardware ases p r e s e n t s a ses are c o n s i d e r e d C o n s t r u c t i o n o f 50 f o o t diameter by 160 f e e t long r o c k e t motor c f o r m i d a b l e c h a l l e n g e t o American I n d u s t r y W h i l e v a r i o u s proces t o have the t e c h n i c a l p o t e n t i a l f o r p r o d u c t i o n o f t h e necessary components a t l e a s t i n t h e o r y sheer s i z e o f b o t h raw m a t e r i a l s r e q u i r e d t o manufacture the p a r t and the f i n i s h e d p a r t s themselves p r e s e n t unique problems Problems o f h a n d l i n g and t r a n s p o r t a t i o n of f i n i s h e d motor cases w e i g h i n g a p p r o x i m a t e l y 1500 tons must be g i v e n c o n s i d e r a t i o n and s t u d y by an a p p r o p r i a t e a u t h o r i t y Q u e s t i o n of m a t e r i a l s u p p l y must be the s u b j e c t o f a p a r a l l e l s t u d y There are no known sources nor p r o s p e c t i v e sources f o r the s u p p l y o f s t e e l or t i t a n i u m i n the s i z e s necessary f o r p r o d u c i n g any o f these components as one p i e c e T h i s makes mandatory the development o f w e l d i n g t e c h n i q u e s t o J o i n raw m a t e r i a l s such as p l a t e s f o r f u r t h e r f o r m i n g i n t o f i n i s h e d p a r t s as w e l l as w e l d i n g t e c h n i q u e s or mechanical d e s i g n s t o j o i n these f i n i s h e d segments i n t o motor cases and c l o s u r e s Continued on next page
CHART 128 PROPOSED DEVELOPMEWT PROGRAM, c o n t i n u e d M a t e r i a l s are c a l l e d f o r i n d e s i g n which are i n the 250 000 t o 450 000 p s l y i e l d s t r e n g t h ranges P r e s e n t l y 250 000 p s i i s a t t a i n a b l e w i t h maraging s t e e l s I t i s reasonable t o assume t h a t m a t e r i a l a t 300 000 p s i w i l l be a v a i l a b l e by 1970 However i t w i l l r e q u i r e a new a l l o y system t o develop s t r e n g t h s s i g n i f i c a n t l y i n excess o f 300 000 p s l y i e l d Such a development should be s u b j e c t o f a p a r a l l e l i n v e s t i g a t i o n The r o l l e x t r u s i o n process d e s p i t e the h i g h i n i t i a l c a p i t a l e x p e n d i t u r e has i n h e r e n t advantages f o r motor case manufacture One o f the most s i g n i f i c a n t advantages i s the complete e l i m i n a t i o n o f l o n g i t u d i n a l welds Any p o s s i b l e use o f w e l d i n g would take p l a c e i n p r e p a r a t i o n o f bl a n k s f o r r o l l e x t r u s i o n and the w o r k i n g o f the weld m e t a l I n the r o l l e x t r u s i o n process i t s e l f would be an u l t i m a t e i n s p e c t i o n T o o l i n g r e q u i r e m e n t s f o r t h i s process would be r e l a t i v e l y i n e x p e n s i v e P r o d u c t i o n o f domes may be f e a s i b l e by r o l l e x t r u s i o n T h i s would be most advan tageous i f t h i s method were e s t a b l i s h e d f o r the p r o d u c t i o n o f c y l i n d r i c a l s e c t i o n s E x p l o s i v e f o r m i n g may be e q u a l l y e f f e c t i v e f o r p r o d u c t i o n o f domes Ring r o l l i n g i s a l o g i c a l source o f blanks f o r r o l l e x t r u s i o n as w e l l as blanks from which Y r i n g s c o u l d be machined Hot s p i n n i n g i s a proven method o f p r o d u c i n g blanks f o r domes Present knowledge would I n d i c a t e t h a t a d i r e c t s c a l e up o f e x i s t i n g equipment i s f e a s i b l e R o l l and weld i s a proven p r o d u c t i o n method which c o u l d be scaled up t o the l a r g e s i z e s under c o n s i d e r a t i o n The e x t e n s i v e w e l d i n g r e q u i r e d f o r t h i s method p r e s e n t s a s e r i o u s drawback Shear s p i n n i n g has some o f the advantages o f r o l l e x t r u s i o n b u t would be l i m i t e d t o e i t h e r c y l i n d r i c a l s e c t i o n s or domes not bot h on the same f a c i l i t y F u r t h e r t o o l i n g f o r t h i s method o f manufacture would be expensive APPROACH 1 Conduct a complete I n v e s t i g a t i o n o f the r o l l e x t r u s i o n process t o i d e n t i f y problems a s s o c i a t e d w i t h the s c a l i n g up o f t h i s process from 13 f o o t diameter t o 50 f o o t diameter T h i s would i n c l u d e but not be l i m i t e d t o machine d e s i g n and con s t r u c t i o n t o l e r a n c e c o n t r o l h a n d l i n g f o r b o t h raw m a t e r i a l and f i n i s h e d pares T h i s should i n c l u d e f e a s i b i l i t y s t u d i e s f o r i n c o r p o r a t i n g the c a p a b i l i t y f o r h o t fo r m i n g t i t a n i u m a t temperatures o f 1000 F t o 1400 F 2 I n v e s t i g a t e t h o r o u g h l y the f e a s i b i l i t y o f the r o l l e x t r u s i o n process f o r Che p r o d u c t i o n o f domes up t o 50 f o o t i n diameter P a r t o f t h i s i n v e s t i g a t i o n should i n c l u d e a st u d y o f the p o s s i b i l i t y o f p r o d u c i n g i n t e g r a l bosses and Y r i n g s t o c k 3 M o n i t o r the r e s u l t s o f the ARPA c o n t r a c t w i t h M a r t i n Denver and U n i v e r s i t y o f Denver t o determine the a d a p t a b i l i t y o f e x p l o s i v e f o r m i n g f o r l a r g e (50 f t d i a ) domes T h i s process should be i n v e s t i g a t e d and i t i s not c l e a r a t t h i s p o i n t how much i n f o r m a t i o n the ARPA c o n t r a c t may develop I n v e s t i g a t i o n should i n c l u d e a study o f the p o s s i b i l i t y o f i n t e g r a l bosses and Y r i n g s t o c k 4 I n v e s t i g a t e c a p a b i l i t y o f Lad i s h r o l l f o r m i n g equipment f o r the p r o d u c t i o n o f l a r g e motor case p a r t s and compare r o l l f o r m i n g and r o l l e x t r u s i o n processes w i t h r e s p e c t t o s u r f a c e f i n i s h e s t o l e r a n c e s s i z e l i m i t a t i o n s c a p i t a l e x p e n d i t u r e f o r equipment c o s t and c o m p l e x i t y o f su p p o r t t o o l i n g
129 PRIORITY RATING WORKSHEET CHART NO P R O G R A M F A C T O a S P R O f l R A M P R O B A B I L I T V O F S U C C E S S ⢠L O W Z M O o e R A T E 5 ⢠W&H 8 C R I T I C A L P R O B t E M S TO B E S O t V e O D F e > ^ / N O T TOO PIPFXCULT Z ⢠S O M E / D I F F I C U L T 5 yL M A N Y / V E R Y D I F F I C U L T 8 G R O W T H P O T E N T I A L >t L I T T L E OR U N D E F I N A e L E O O f ^ E C O f i N I Z A B L E P o r E M T I A L 4- O T H E R T H A N AIR F O R C E N O N E O M A N Y e NECESSITY FOR AIR FORCe FUNDINQ D LOW HlfiH lUmSTI lV/ 'CTHEft GOVT E F F C C T ^ ^ (XCOtttATE - SoMe E F F O t T orM(A 'SCIie<3eS ⢠e K c u J s i y r A I R F « i t £ L ^\^wnb u*x\m \i. P R O C E S S A P P L I C A T I O N S ⢠NEED FACTORS S Y S T E M S P R O B A B I L I T Y H i a H P R O B A B I L I T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y V e R Y H K T H H I < S H F A I R L O W F R E Q U E N C Y O F R E Q U I R E M E N T IN S Y S T E M MORE T H A N 3 C C > M P « * l e U T 9 Z 3 C ^ M P e U e M T S S l N f l L E C O M P C N E N T D e s \ a N A L T E R M A T E S N o A L T E B N A T e R w e s E E N ONE A L T E R M A T E S E V E R A L A U T E R M A T E « M A T E R I A L S I M P L K T A T I O N N t W M A EB.1A1- o t v e u j f M e M T S e a o M A T E R I A L I M P l W > V t M E N T R E i f i D NO P R o a t E M F o R C s e e u IZ 8 4 I Z 9 3 3 I 3 6 o CALCULATE PRIORITY 9 R A W S C O R E S F O R E A C H ⢠Z E F E K e M O P CoMFONCt lT IH T A B L E S A T t W D O F P A U E t IJtpetT W I T H T J A W T i T r t L S E N T E R E P IN â¢SUMMAeV fn- I216HT S Y S T E M S A A R P RA>M SeoOES a 2a STEP I STEP 2 3 2 CIRCLE HIGHEST AARP 1?AW S C O R E IN eACH OTHER SVSTEM C I R C L E NEXT HIGHEST SCORE IF WITHIN 4 FVIMTS OF TOP SCORE n ^ LOW 2 . N U M & E R OF S V ^ T E I V S HldH STEP 3 CIRCLE N U N i a e R O F S Y S T E M S L O W FREOU6NCY DISTRIBUTION FACTOR MUMseti . OP s y s r c M S riiart B E L O W i 1 3 o K M « L 6 2 KMOOE 1 0 1 £ \ 4 1 1 1 3 1 t z 1 *!⢠⢠⢠c ⢠p = n « f = TOTAL = PRIORITY x f f -
130 TITLE FORMING SANDWICH BULKHEAD AND CYLINDRICAL PANEL SHAPES CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Produce double w a l l e d bulkheads and c y l i n d e r s Both w a l l s t o f i t a sandwich core c l o s e enough t o a l l o w bonding E l l i p s o i d a l bulkheads are 60 + 0 05 inches t o 600 + 0 15 inches r a d i i c y l i n d e r l e n g t h s up t o 600 inches t h i c k n e s s e s o f s k i n s are 0 005 i n c h t o 0 060 i n c h + 0 001 I n c h sandwich t h i c k n e s s e s are 0 125 i n c h t o 3 0 + 0 002 Inches Face sheets are a or m $ t i t a n i u m Core i s thermoset o r g a n i c p l a s t i c and bonded w i t h o r g a n i c adhesive AARP REFERENCES E Chn 180 B C h a I s . 184 95a 96 P 4 F V P S C h a r t s . APPLICABLE PROCESS EXPLOSIVE FORMING STRETCH FORM (BULKHEADS) CREEP AGE (CYLINDERS) ROLL FORM AND C e d e 3 08 01 3 03 05 3 03 07/3 03 21 STATE OF THE ART ASSESSMENT E x p l o s i v e ForminR Wax f i l l e d sandwich bulkhead panels have been e x p l o s i v e l y formed w i t h double w a l l s up t o 60 i n c h r a d i u s Walls were aluminum Larger r a d i i bulkheads o f aluminum have been made i n gore s e c t i o n s by e x p l o s i v e f o r m i n g but w i t h o u t sandwich (108 i n c h r a d i u s ) Forming a l l sandwich components t o g e t h e r p r o v i d e d f i t up which was adequate f o r bonding C y l i n d e r s have been e x p l o s i v e l y formed o f v a r y i n g d i a m e t e r s o f p r a c t i c a l l y a l l m e t a l s and a l l o y s Sandwiching on c y l i n d r i c a l bodies i s a l e s s c r i t i c a l t o l e r a n c e problem than i n bulkheads S t r e t c h Form Bulkheads up t o 198 nch i n r a d i u s have been s t r e t c h formed i n segments on the S a t u r n program w i t h 2014 A l Segments had been welded b e f o r e bonding w i t h a p p r e c i a b l e t o l e r a n c e d i f f i c u l t i e s i n the bonding o p e r a t i o n Bonding b e f o r e w e l d i n g may a l l e v i a t e the bonding f i t up problem but w i l l r e q u i r e w e l d i n g w i t h o u t damage t o the bond or core R o l l Form Since i n the c y l i n d r i c a l shape the p a r t s are f l e x i b l e enough t o a l l o w d i s t o r t i o n t o f i t the core d u r i n g bonding the s t a t e o f the a r t i s adequate t o s u p p l y honeycomb c y l i n d e r s r e q u i r e d Sheets would be r o l l formed bonded t o a common core and welded t o the complete c y l i n d e r Welding development may be r e q u i r e d and h a n d l i n g i s a problem Continued on next page ALTERNATE PROCESSES NONE C o d e
131 CHART NO <^Oto CRITICAL PROBLEMS E x p l o s i v e Forming 1 S c a l i n g up t o the s i z e s r e q u i r e d needs R & D M a r t i n Denver e x p l o s i v e f o r m i n g program w i l l shed l i g h t on and p o s s i b l y s o l v e t h i s problem 2 Tolerance c o n t r o l ( b o t h t h i c k n e s s and r a d i a l ) i s t i g h t Springback must be c o n t r o l l e d Aging must not cause t o l e r a n c e d e v i a t i o n s 3 Demonstration o f core f i l l e d e x p l o s i v e f o r m i n g or e x p l o s i v e s i z i n g i s r e q u i r e d f o r t i t a n i u m a l l o y s S t r e t c h Form 1 The two s k i n p a r t s must be formed s e p a r a t e l y n e c e s s i t a t i n g v e r y c l o s e t o l e r a n c e c o n t r o l i f the two are t o be bonded s a t i s f a c t o r i l y t o a common honeycomb core 2 Welding must f o l l o w f o r m i n g and bonding un l e s s t o l e r a n c e s are c o n t r o l l e d by d i f f i c u l t core c o n t o u r i n g or perhaps by c o n c u r r e n t wax f i l l e d e x p l o s i v e s i z i n g o f whole domes p r i o r t o bonding Welding a f t e r bonding r e q u i r e s b o t h s k i n s t o be welded s i m u l t a n e o u s l y t o a v o i d warpage T h i s c r e a t e s a d i f f i c u l t I n s p e c t i o n problem R o l l Form Creep or age s i z i n g equipment i s not a v a i l a b l e t o handle the l a r g e s t a v a i l a b l e t i t a n i u m sl i p e t s General H a n d l i n g and t r a n s p o r t a t i o n o f l a r g e t h i n w a l l e d bulkheads and c y l i n d e r s PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop a method f o r f o r m i n g l a r g e t h i n w a l l e d weldment e l l i p s o i d a l domes o f IT and a 8 t i t a n i u m which i s c o m p a t i b l e w i t h the problems o f bonding the dome s k i n s t o a common p l a s t i c honeycomb cor e BACKGROUND The re q u i r e m e n t s o f c l o s e f i t up t o achieve bonding between core and s k i n s p l a c e v e r y d i f f i c u l t t o l e r a n c e r e s t r i c t i o n s on the dome s k i n s i f the domes are t o be f a b r i c a t e d s e p a r a t e l y and subsequently bonded t o t h e i r common honeycomb core T h i s problem has been encountered w i t h aluminum a l l o y bulkhead s k i n s m Saturn APPROACH 1 Match Form, Age. Bond. Weld The p r i m a r y process developments w i l l be t o co fo r m t i t a n i u m p a n e l s w i t h a f i l l e d core s e p a r a t o r which i s not bonded t o the s k i n s a t the time o f f o r m i n g Problems t o be overcome i n c l u d e m i n i m i z a t i o n o f sp r i n g b a c k d u r i n g f o r m i n g the v e r i f i c a t i o n o f the f o r m i n g process i t s e l f and w e l d i n g procedures which w i l l not damage the bond Non d e s t r u c t i v e i n s p e c t i o n o f welds made a f t e r bonding o f the honeycomb poses s e r i o u s problems w h i c h r e q u i r e i n v e s t i g a t i o n and s o l u t i o n 2 Weld, Match Form or Rough Form. Age. Match S i z e , and Bond The p r i m a r y c h a l l e n g e t o t h i s approach i s the e x p l o s i v e f o r m i n g o f v e r y l a r g e welded bla n k s and the match ( f i l l e d honeycomb cor e s p a c e r ) s i z i n g o f these same l a r g e p a r t s a f t e r a g i n g Furnace problems a s s o c i a t e d w i t h h a n d l i n g a g i n g and bonding l a r g e p a r t s w i l l be acute
132 PRIORITY RATING WORKSHEET CHART P R O G R A M P R O B A B I L I T Y O F S U C C E S S ⢠LOW 2. ⢠MODERATe 5 H I A H 8 C R I T I C A L P R O B L E M S TO B E S O L V E D a F E W / N O T T O O P I F F W U L T Z ⢠9 0 M E / D I F F I C U L T 3 K M A N Y / V E R Y D I F F I C U L T 8 PROCESS GROWTH POTENTIAL a L I T T U E O R U N D E F I N A & L C O ^ geCtAHMMie P O T E M T I A L 4 A P P L I C A T I O N S O T H E R T H A N A I R F O R C E ⢠N O N E O )S, S O M E ^ D M A N Y e N E C E S S I T Y F O R A I R F O R C E F U N D I N O n LOW HISH INTUSTEV/in-HeA <SMT E F F O i r If MSPtttATB - SOME BTOtX OfMEU â¢Seu««£9 8 ⢠t*ciMitÂ¥e A I R F O I U L F U M P N A L I K E L W 1 2 . NEED FACTORS S Y S T E M S P R O B A B I L I T Y H IQH P R O B A B I L I T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y V E R Y H K T H H I A H F / V I R L O W F R E Q U E N C Y O F R E Q U I R E M E N T IN S Y S T E M MCHC T H A N 3 C O M P a N E H T S 2. 3 c ^ M P e N E w r s S I N G L E C O M P O N E N T D E S I G N A L T E R N A T E S No A L T E R N A T e n M E s E E N O N E A L T E R N A T E S E V E R A L A L T E R N A T E S M A T E R I A L S I M P L I C A T I O N N e w MATE|2 . | ( IL P e y e i O ^ M E N T RCdt o M A T E R I A L I M P R O V E M E N T R E a ' P NO P R C & U E M r o C C S E E N IZ 8 4 I I 9 S> 3 3 2 I <3 6 3 6 4 o CALCULATE PRIORITY 8 e 3Z R A W F O R E A C H R E F E i t e i K t P COMF0NCMT I N T A B L E S A T t N C o r P A N E L ^tPatT W I T H l i A l O T O T A L S E N T E R C P M /w IZISMT S Y S T E M S A A R P RA>M SCoSeS STEP I CIRCLE MIGHEST AARP RAW S C O R E n s STEP 2 IN EACH OTHER SVSTEM C I R C L E NEXT HIGHEST SCORE IF WITHIN 4 POINTS OF TOP S C O R E N U M B E R O F S V S T E W S HlAH / LOW L STEP 3 CIRCLE N U M Q E R . O F S Y S T E M S L O W FREQUENCY DISTRIBUTION FACTOR NuMoen . O P S Y S T C M S rtisrt I Son MMLE 0 I 2 R M O « t 1 0 1 z. I 4 1 3 1 4 \ z 1 *f 1 4 TOTAL B&LOWi PRIORITY
133 TITLE HOT SIZING CONICAL ZEE RINGS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Make Zee frames t o f i t cone or c y l i n d r i c a l i n t e r s t a g e s k i r t The s k i r t maximum r a d i u s w i l l be 360 inches w i t h a t o l e r a n c e o f + 0 080 inches The Zee frame w i l l have w a l l t h i c k n e s s r a n g i n g from 0 030 t o 0 100 + 0 001 Inches w i t h a maximum depth o f 24 + 0 1 i n c h The m a t e r i a l w i l l be B t i t a n i u m AARP REFERENCES E C h a r t s . B C h a r t s . 185 97a P S F V P S C h a r t s . APPLICABLE PROCESS ROLL FORM FOLLOWED BY HOT SIZING OR AGE SIZING C o d e 3 03 07 STATE OF THE ART ASSESSMENT The a l t e r n a t e process o f f o r m i n g i n segments and w e l d i n g t o g e t h e r i s w i t h i n the s t a t e o f the a r t except f o r the s i z i n g problem which i s coiranon t o bot h approaches The area i n which development i s r e q u i r e d i s t o produce the v e r y l a r g e diameter Zee shaped r i n g i n one p a r t w i t h no weld lands w h i c h would r e q u i r e an Inc r e a s e i n w e i g h t The t e c h n i q u e f o r f o r m i n g t h i s l a r g e r i n g would be by r i n g - r o l l e d f o r g i n g Development i s r e q u i r e d o n l y i n s c a l i n g up o f h a n d l i n g f a c i l i t i e s the r o l l i n g o p e r a t i o n I t s e l f i s w i t h i n p r e s e n t c a p a b i l i t i e s C i r c u l a r s e c t i o n s up t o 260 i n c h diameter by 34 i n c h h i g h have a l r e a d y been r i n g r o l l e d on e x i s t i n g equipment by the L a d i s h Company T h i s equipment can produce I n t e g r a l r e i n f o r c i n g r i b s and f l a n g e s t o c l o s e d i m e n s i o n a l t o l e r a n c e s The major l i m i t a t i o n i n the c a p a b i l i t y o f t h i s equipment i s i n t h e a v a i l a b l e s i z e and q u a l i t y o f s t a r t i n g i n g o t s The l a r g e s t c u r r e n t l y a v a i l a b l e I n g o t s o f m a t e r i a l s such as t i t a n i u m and vacuum melted maraging s t e e l s can be handled on the e x i s t i n g equipment A f t e r the p a r t i s formed i t must be heat t r e a t e d T h i s can comprise merely an age tr e a t m e n t w i t h i n the p r e s e n t stage o f B t i t a n i u m a l l o y development I f s i z i n g i s t o be a t t a i n e d c o n c u r r e n t w i t h a g i n g means must be developed t o a p p l y f l u i d p r e s s u r e t o push the r i n g a g a i n s t an 0 D s i z i n g r i n g means f o r h o l d i n g temperature over the whole r i n g must a l s o be p r o v i d e d M a t e r i a l p r o p e r t i e s r e q u i r e d cannot be met w i t h p r e s e n t S t i t a n i u m a l l o y s but a l l o y s w i t h the r e q u i r e d p r o p e r t i e s should be a v a i l a b l e by 1970 1975 Improvements may a l t e r param e t e r s o f age f o r m i n g process CRITICAL PROBLEMS 1 H a n d l i n g the r i n g d u r i n g the r i n g - r o l l f o r g i n g and d u r i n g a l l subsequent o p e r a t i o n s up t o and i n c l u d i n g I n s t a l l a t i o n t o the i n t e r s k l r t p a r t The l a r g e r diameter r i n g s may weigh up t o one t o n and w i l l be f l e x i b l e 2 Means must be developed f o r p r o v i d i n g p r e s s u r e and temperature d u r i n g the age s i z i n g o p e r a t i o n A l s o d a t a must be generated t o p r e d i c t s h r i n k a g e f r o m the age s i z i n g o p e r a t i o n i n Continued on next page ALTERNATE PROCESSES BEND TO ZEE STRETCH FORM TO RADIUS WELD SEGMENTS TO RING C o d e 3 03 01/3 03 05
134 CHART NO «a^7 CRITICAL PROBLEMS, co n t i n u e d order t o r e a l i z e the f i n a l t o l e r a n c e s r e q u i r e d 3 The w a l l t h i c k n e s s t o l e r a n c e i s e x t r e m e l y t i g h t and p r o b a b l y u n r e a l i s t i c be a t t a i n e d t h i s proposes a c r i t i c a l problem I f i t must PROPOSED DEVELOPMENT PROGRAM OBJECTIVE The o b j e c t i v e o f t h i s development program w i l l be t o conc e i v e and demonstrate m a n u f a c t u r i n g t e c h n i q u e s f o r p r o d u c i n g l a r g e diameter r i n g s h a v i n g a Zee c r o s s s e c t i o n the m a t e r i a l t o be "3 t i t a n i u m The suggested approach t o the problem I S r i n g r o l l f o r g i n g f o l l o w e d by age s i z i n g APPROACH The f a b r i c a t i o n development r e q u i r e d can be separated i n t o two major phases (1) Ring r o l l f o r g i n g o f a 380 i n c h r a d i u s Zee c r o s s s e c t i o n r i n g and (2) age s i z i n g o f t h i s r i n g t o c l o s e t o l e r a n c e s I t i s suggested t h a t the development program be performed f i r s t on sub sca l e p a r t s u s i n g t e c h n i q u e s which can be sca l e d up t o the v e r y l a r g e s i z e r e q u i r e d I n view o f the p r e s e n t s t a t e o f development o f r i n g r o l l i n g equipment f o r l a r g e r i n g s the o n l y p o i n t t h a t may r e q u i r e d e m o n s t r a t i o n I s the c a p a b i l i t y o f pr o d u c i n g t y p i c a l Zee shapes on e x i s t i n g r i n g r o l l i n g f a c i l i t i e s The a b i l i t y t o r i n g r o l l r e i n f o r c i n g r i b s as w e l l as lands and f l a n g e s a t the ends o f c y l i n d e r s used f o r l a r g e r o c k e t motor cases has a l r e a d y been demonstrated Techniques f o r age s i z i n g which must be developed would i n c l u d e p o i t a b l e or i n p l a c e assembled fu r n a c e s and j i g t , i n g f o r the s i z i n g o p e r a t i o n J i g g i n g would i n c l u d e a s t r o n g back or f i x e I diameter r e f e r e n c e r i n g and a means f o r a semi p o r t a b l e on the i n s i d e diameter s u r f a c e An example concept n i g h t be a semi p o r t a b l e doughnut shaped a u t o c l a v e T h i s a u t o c l a v e or s i m i l a r means should be s u f f i c i e n t l y v e r s a t i l e t o accommodate r i n g s o f v a r y i n g diameter upon disassembly and reassembly
135 PRIORITY RATING WORKSHEET CHART P R p g ^ p A M F A C T O R S P R O G R A M P R O B A B I L I T Y O F S U C C E S S D LOW ⢠M O D E R A T E ft wan C R I T I C A L P R O B L E M S TO B E S O L V E D a F E W / N O T TOO D I F F I C U L T X, S O M E / D I F F I C U L T Q M A N Y / V E R Y D I F F I C U L T G R O W T H P O T E N T I A L D L I T T L E OR U N O E F I N A B L E ( Z e e O S N a A B L E P O T E N T I A L O T H E R T X A N A IR F O R C E NONE S O M E M A N Y F O R AIR FORCe FUNOIWa LOW HlfiH IHIUSTEV/ 'c irHEA <aOVr C F F O t T 4 MeotHATE - s e i n E E F n c T oTHcR â¢saieees e a e K C W S I f E A lR FeftCfc F U M P w a U K f L X 14. P R O C E S S A P P L I C A T I O N S n 2 5 8 Z 9 8 o 4 o 4 NECESSITY NEED FACTORS S Y S T E M S P R O B A B I L I T Y H i a H P R O B A B I L I T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y V E R Y H K T H H I A H F A I R L O W F R E O U E N O Y O F R E Q U I R E M E N T IN S Y S T E M MORE T H A N 3 C O M P e N E H T S Z 3 C e M P o N E M r S S l N f l L E C o M P e N E N T D e s \ a N A L T E R N A T E S N o A L T E R N A T E R t S E S E E N ONE A L T E R N A T E S E V E R A L A L T E R N A T E * M A T E R I A L S I M P L I C A T I O N NEW M A efc l f lL PevEtOFMEMT REOt O M A T E R I A L I M P R O V E M E N T R £ ( a > D NO P f l c B u E M F o R C s e e u IZ 8 4 VL 9 3 3 2 I <J 6 3 « 4 o CALCULATE PRIORITY 29 RAW s c o o e s F O R E A C H R E F E R e r i C E P C O M P O N E N T IN T A B L E S AT t N C O F P A N E L 12EP«».T W I T H l iA lO T o r n t S E N T E O r P n i ^ u M M n e v fx IZlfiMT S Y S T E M S B-'kfO A A R P RA>W SCORES STEP I STEP 2 STEP 3 2^ CIRCLE HIGHEST AARP RAW S C O R E IN EACH OTHER SYSTEM CIRCLE NEXT HIGHEST SCORE IF WITHIN 4 POINTS o r TOP SCORE n" N U M & E R OF S V S T E M S HidH CIRCLE LOW FREQUENCY DISTRIBUTION FACTOR NUMBen. ov S Y S T E M S H I G H f " B E L O W I 1 3 O K MMCe N U M & E R O F S Y S T E M S L o w 0 I 2 RMOOE t 0 1 a \ 4 1 3 1 1 7. 1 «f 1 4 !⢠H a n d iri 11 1 ⢠⢠⢠c I I 1 ⢠⢠⢠⢠II 1 ⢠⢠⢠C I ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠c I I 1 ⢠⢠⢠⢠l U ⢠⢠⢠c ⢠⢠⢠⢠c ! ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠1 ^ ⢠⢠⢠⢠i r n ⢠⢠⢠L 1 II II I I ' I I 1 11 1 II II II ⢠⢠⢠⢠II 1 ⢠⢠⢠⢠II 1 ⢠⢠⢠L _ II 1 p = 2^ TOTAL = S i PRIORITY <ff
I T ITLE FORMING TOROIDAL SHAPES 136 C H A R T P R I O R I T Y RELATED CAMR CHARTS noi M A N U F A C T U R I N G R E Q U I R E M E N T To produce sections ulilch can be welded Into a t o r o l d tank the o v e r a l l tank to have minor r a d i i ranging from 30 + 0 03 inches up to 120 + 0 08 Inches major r a d i i ranging from 60 + 0 05 Inches up to 480 + 0 50 inches w a l l thicknesses to range from 0 005 inch up to 0 100 + 0 001 inches material to be a u s t e n i t i c stainless steel or maraging s t e e l These skins w i l l be formed to compound and a n t i c l a s t i c curvatures w i t h large r a t i o s of bend radius to thickness and w i l l be d i f f i c u l t to hold to shape without d i s t o r t i o n A A R P R E F E R E N C E S E C h n r U B r h n r , . 95b PSFVPS C h a r t s A P P L I C A B L E P R O C E S S Code 3 08 01 EXPLOSIVE FORMING or DRAPE FORMING 3 03 06 S T A T E O F T H E A R T A S S E S S M E N T Explosive Forming Explosive forming is c u r r e n t l y being developed for large dome sections using both large size r o l l e d sheet and large sheet made by fusion welding together smaller sheet segments The various shapes being explosively formed are generally figures of r e v o l u t i o n or shapes which are not a n t i c l a s t i c Toroidal tank segments up to 10 feet major diameter can be shear formed and explosively sized using presently available shear forming equipment Two half sections of t o r o i d a l tanks up to 10 foot i n major diameter can be g i r t h welded together around both the inner and outer circumferences to form the completed torus Limitations i n size of s t a r t i n g sheet can be overcome by fusion welding together smaller f l a t sheet For la ge size c o r i i up to t i e 80 feec major diameter maximum size the tanks can be fabricated by welding together formed segments The formed segments can be s t r e t c h formed st r e t c h formed and explosively sized or explosively formed using welded preformed segments The largest torus having a minor diameter of 20 feet and a major diameter of 80 feet can be fabricated by welding together twenty four segments of waicn sixteen would be i d e n t i c a l l / 8 t l i segments of the outer circumferential surface and eight would be i d e n t i c a l l / 4 t h segments of the Inner c i r c u m f e r e n t i a l surface Each segment would represent a quarter section of a v e r t i c a l s l i c e through the 30 feet diameter c i r c u l a r section of the tank I t would be necessary to form the segments i n heavier thicknesses followed by chem m i l l i n g for buildup at the weld seams and to provide s t i f f e n i n g r i b s This design feature may a l l e v i a t e handling problems as w e l l as d i s t o r t i o n during f a b r i c a t i o n and transportation of both the segments and the completed tank Build up of weld seams i s p a r t i c u l a r l y required i f cold worked to strength austenitic stainless steel i s employed This b u i l d up can be achieved either by chem-milllng to leave heavier lands at the weld seams or by fusion butt welding followed by the addition of doubler s t r i p s spot welded at both sides of the fusion weld Continued on next page A L T E R N A T E P R O C E S S E S NONE Code
C H A R T 137 STATE OF THE ART ASSESSMENT, continued Experiments are In progress to form maraglng steels and austenltlc stainless steels M u l t i p l e shots w i l l probably be required to form the compound curvatures required f o r t o r o i d a l tank designs Drape Forming Drape forming I s a r e l a t i v e l y new process which has proven successful i n forming skin sections of aluminum for a 200 inch major diameter torus tank However t h i s process depends on being able to heat a die l o c a l l y to temperatures s u f f i c i e n t l y high to reduce the forming stress at the loca t i o n and thus to c o n t r o l forming Appreciably higher temperatures w i l l be required to Influence forming stress w i t h steels than have been necessary for aluminum C R I T I C A L P R O B L E M S Explosive Forming 1 A primary problem w i l l be handling such f l e x i b l e structures during the trimming possible heat treatment and other operations which f a l l between forming and welding This may be some what a l l e v i a t e d by sandwich forming carrying the sandwich material along w i t h the skin material as support j i g g i n g 2 Material toughness w i l l be a problem i f maraglng steel i s to be used i n these t h i n sections Regardless of the material the ultimate strength to density r a t i o requirements of 9 x 105 inch w i l l require material development which may Influence f o r m a b l l l t y 3 I t w i l l be advantageous as regards holding o v e r a l l tank tolerances to minimize welding This w i l l d i c t a t e that the largest available sheet size be used However forming requirements w i l l become more d i f f i c u l t as sheet size increases Very large t o r o i d a l sections have not previously been produced by the explosive forming process 4 Thickness tolerance of + 0 001 inch i n f o i l and sheet gauges from 0 005 inch to 0 100 inch represents a c r i t i c a l problem Sendzimlr r o l l e d sheet up to 48 Inches and possibly 60 Inches i n width i s c u r r e n t l y available i n gauges up to 0 030 inch w i t h thickness tolerances of + 0 001 inch or less At 0 062 inch thickness the least thickness tolerance may be of the order of + 0 002 inches Base material thickness tolerance w i l l have to be Improved to meet the recommended design requirements Drape Forming The process needs v e r i f i c a t i o n for the higher forming temperature materials Forming at such temperatures w i l l eliminate any cold r o l l i n g c o n t r i b u t i o n to mechanical properties which probably r e s t r i c t s t h i s process to ap p l i c a t i o n w i t h maraglng steels Maraglng steels encounter a toughness problem w i t h the present tate of the a r t In t h i s thickness range P R O P O S E D D E V E L O P M E N T P R O G R A M OBJECTIVE To develop methods for forming large t o r o i d a l tank sections with outer tank radius/sheet thickness r a t i o greater than 5000 of materials such as austenltlc stainless steels or maraglng stainless steels APPROACH This proposed development concerns p r i m a r i l y the forming problem but the material handling and welding problems must be considered also Since shapes similar to th i s requirement have not received much experimental forming a t t e n t i o n p a r t i c u l a r l y w i t h higher forming temperature alloys i t is suggested that an I n i t i a l forming f e a s i b i l i t y program be funded which is a sub scale comparative evaluation of the two processes explosive forming and drape forming However even the sub scale experiments must s t i l l be f a i r l y large (on the order of 1/2 to 1/3 the dimensions Continued on next page
C H A R T - 1 3 8 - PROPOSED DEVELOPMENT PROGRAM, continued of the l a r g e s t proposed t o r o i d a l tank) because f u r t h e r scale-down f o r c e s sheet thickness Into an I m p r a c t i c a l and unavailable range Thicknesses of sheet during the forming operation should be at l e a s t twice (times the s c a l e f a c t o r ) those v a l u e s required I n the f i n a l product s i n c e chem-mllllng i s a n t i c i p a t e d for weld J o i n t s I n order to make the s c a l e t e s t s r e a l i s t i c the s t a r t i n g sheet should be made up from smaller sheet f u s i o n welded together I n the case of cold r o l l e d to- strength a u s C e n l t l c s t a i n l e s s s t e e l (Type 301 for example) these weld J o i n t s w i l l r e q u i r e strengthening by attachment of doublers a f t e r forming to shape After forming and s i z i n g the segments should be Joined by appropriate welding techniques R e q u i s i t e t o o l i n g concepts should be developed and evaluated and e i t h e r an e n t i r e t o r o i d a l tank or a s u f f i c i e n t p ortion of one should be f a b r i c a t e d to prove out the manufacturing processes e s t a b l i s h e d for production of large t o r o i d a l tank s t r u c t u r e s The attendant design study should Include c o n s i d e r a t i o n of s t i f f e n i n g r i b s and i f such are d e s i r a b l e manufacturing techniques for t h e i r incorporation should be developed and evaluated
139 PRIORITY RATING WORKSHEET CHART NO 2.0$ P R O S R A M F A C T O R S P R O f i R A M P R O B A B I L I T y O F S U C C E S S D l o w M O D E R A T E ⢠H i a H C R I T I C A L P R O B L E M S TO B E SOLVED n F E W / N O T TOO P I f F W U L T ⢠3 0 M E / D I F F I C U L T X M A N Y / V E R Y D I F F I C U L T PROCeSS G R O W T H P O T E N T I A L X L I T T L E OR U N D E F I N A & L E D K E C 0 6 N I Z . A B L E P O T B M T I A L A P P L I C A T I O N S O T H E R T W A N AIR FORCE ⢠NONE X ^ O M E n M A N Y N e C E S S I T Y FOR A I R z 5 8 2 6 o 4- o 4 FORCE FUNOINQ D LOW HI6H |lllJttSTttV/<ITH£A (SOVT E F F ttf <(. K r^eOERATE - S l W t 6FF0«LT OrHtU â¢SWCfiCS 8 ⢠EI<£UJS1^E Am F e f t C t F U N P M I L I K E H J 14. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIOH P B O B A B I L l T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y V E R Y H K T H H I « H F A I R L O W F R E f l U E N C Y OF R E Q U I R E M E N T IN S Y S T E M M e n e T H A N 3 C C M P S N E N T S 2 3 C e M P t M E N T S S I N f l L E C O M P C T I E M T OeS lSN A L T E R N A T E S NO A L T E R N A T e R i a E s E E N ONE A L T E R N A T E S E V E R A L A L T E R W A T E « M A T E R I A L S I M P L I C A T I O N NEW MATECin P e v U)?M£NT BCU O MATECIAL I M P R O V E M E N T Ee<a>D NO P R e s L E M F o e c ? c e » i CALCULATE PRIORITY S T E P I S T E P 7. 8 8 2^ RAW s c o « e s F O R EACM R E F C K E N ^ X P COMPCNCMT IH T A B L t S A T t N D O F P A N E L RtPetT W I T H liAlO T O T H L S E N T E R E D IN AT eifiWT AARP RAVJ SCoftCS C I R C L E H I G H E S T A A R P 1?AW S C O R E H i IN E A C H OTHER S Y S T E M C I R C L E N E X T H I G H E S T 3Z I F W I T H I N N U M & E R OF 4 P O I N T S ⢠S V S T E M S H l d H O F T O P S C O R E I. L O W S T E P 3 C I R C L E N U M & E R O F S Y S T E M S L O W F R E Q U E N C Y D I S T R I B U T I O N F A C T O R NUMBen. OP s v s r t M s rt a r t I 2. 3 OK i>4o«Le SCORE BE.LOWI 0 I 2 R Mooe t 0 1 a I * \ 1 3 1 *f 1 £ 1 * f 1 4 ⢠⢠⢠⢠o n T O T A L PRIORITY
140 TITLE FORMING LARGE INTEGRALLY STIFFENED TRUNCATED CONICAL SEGMENTS C H A R T N O P R I O R I T Y RELATED CAMR CHARTS M A N U F A C T U R I N G R E Q U I R E M E N T Form sculptured i n t e g r a l l y s t i f f e n e d segments of a truncated conical thrust structure having a maximum height of 240 + 0 5 inches a maximum radius of 180 + 0 08 inches a w a l l thickness i n the sculptured cross section of approximately 0 5 + 0 010 inch machined from 1 CO 3 inch plate sections The emphasis for these thrust sections of space launch systems is to provide s t r u c t u r a l e f f i c i e n c y at minimum weight by use of close tolerance I n t e g r a l structures Material is Beta titanium with (FcyE/p) at 600 F a 1 5 x 10l3 i b s / i n A A R P R E F E R E N C E S E C h a t _ 170 B Cha I 93 PSFVPS Charts. A P P L I C A B L E P R O C E S S Either (A) EXPLOSIVE FORMING OF PREVIOUSLY SCULPTURED SEGMENTS or (B) ROLL BEND OR BRAKE FORMING 08 01 03 01 Code S T A T E O F T H E A R T A S S E S S M E N T Explosive ForminR of Previously Sculptured Segments The requirement of beta titanium a l l o y having a (FcyE/o) at 600F s 1 5 x 10^3 l b s / i n cannot be met by presently available alloys Present alloys are l i m i t e d to a maximum of 1 2 1 3 X 10l3 l b s / i n i n the s o l u t i o n quenched and aged condition A materials development program w i l l be required to meet the s t i p u l a t e d mechanical property requirements Explosive forming of sculptured waffle sections of 2014 T6 aluminum a l l o y gore skins for Che SaCurn S I I bulkhead has been developed as a producclon process by North American Aviation This process has been used since 1962 for the forming of hundreds of double curvature sections up to 5 fC X 7 f t i n size and 1 1/2 inches in Chlckness These sections had waffle patterns approximately 10 inches square w i t h 1/2 inch wide ribs machined in the f l a t plate condition The sculpCured pockeCs are f i l l e d w i t h Cerro bend (a low cemperature melting a l l o y ) and then explosion formed wich Che f l a t surface i n contact with the die face (waffle pattern on inside surface of bulkhead) The Cerro bend a l l o y is then melted out with steam Insofar as aluminum alloys are concerned i t can be concluded chat explosion forming of moderately t h i c k i n t e g r a l l y s t i f f e n e d double curvature s t r u c t u r a l segments Is an already developed production process This process has not been applied to CiCanium alloys and the higher strength and modulus of t i t a n i u m w i l l undoubtedly pose problems i n springback as w e l l as i n the development of f i l l e r materials having r e q u i s i t e properties Roll Bend or Brake Forming of Previously Sculptured Segments The process of r o l l bend or brake forming of sculptured waffle segments of aluminum a l l o y plate is currencly being employed i n Che fabricaCion of the Saturn S I I stage The single radius curvature of c y l i n d r i c a l tank walls of t h i s vehicle are being produced by the above praccices No pockec f i l l e r material is required i n thinner plate (up to possible 1 inch thickness) but cnicker place up to 3 inch thickness (for example 1/2 inch face sheet and 2 1/2 inch deep r i b s ) w i l l probably require f i l l e r i n the pockets to prevent buckling or c r i p p l i n g of the r i b s A L T E R N A T E P R O C E S S E S NONE Code
141 C H A R T ^ « C R I T I C A L P R O B L E M S 1 Beta titanium alloys having required strength properties at 600 F are not cu r r e n t l y available 2 Sculpturing of waffle patterns i n th i c k plate of beta titanium a l l o y poses d i f f i c u l t and co s t l y machining problems 3 'Explosion forming would undoubtedly be performed i n the annealed condition Age hardening a f t e r explosion forming may cause d i s t o r t i o n requiring explosion sizing operations 4 Scale up of process to explosive form large panels to minimize the number of parts needed to f a b r i c a t e very large structures may pose serious problems Maximum available size of 1 inch to 3 inch thick titanium plate may pose c r i t i c a l l i m i t a t i o n s 5 Buckling or c r i p p l i n g of the r i b s must be prevented during r o l l bend or brake forming P R O P O S E D D E V E L O P M E N T P R O G R A M OBJECTIVE To advance the explosive forming process to develop double radius curvatures i n large t h i c k plates of i n t e g r a l l y s t i f f e n e d beta titanium a l l o y to develop appropriate f i l l e i | material to prevent buckling and c r i p p l i n g of web sections during explosive forming and r o l l and brake bending to develop processes to pre form pockets i n i n t e g r a l l y s t i f f e n e d plate to minimize machining costs and material wastage and to develop post hardening explosive s i z i n g processes BACKGROUND Explosive forming of double curvature segments of previously sculptured waffle pattern plates of aluminum a l l o y up to 1 1/2 inch i n thickness and 5 f t x 7 f t i n size has already been successfully developed as a production practice Likewise single radius curvature forming of c y l i n d r i c a l sections of waffle pattern aluminum a l l o y plate is a developed process The extension and appl i c a t i o n of these processes to considerably thicker and larger i n t e g r a l l y s t i f f e n e d beta titanium a l l o y plate poses several problems that require manufacturing development studies to resolve Since the machining of pockets i n a waffle pattern s t i f f e n e d section would be a c o s t l y and time consuming process the preforming of these pockets by press or r o l l forging or by explosive forging would be advantageous and the f e a s i b i l i t y of these developments should be evaluated APPROACH ing hardened plate should be evaluated to determine t h e i r l i m i t s Since the curvatures of i n d i v i d u a l segments of very large structures (15 to 30 f t i n diameter) may be r e l a t i v e l y minor i t may be possible to explosion form the a l l o y i n the f u l l y hardened condition This study should consider various r a t i o s of plate thickness to web heights 2 Investigate various f i l l e r materials to select one which prevents buckling or c r i p p l i n g of the s t i f f e n i n g r i b s or webs 3 Investigate the explosive sizing of formed and age hardened i n t e g r a l l y s t i f f e n e d plate segments 4 Investigate problems of scale up of the process to thicker i n t e g r a l l y s t i f f e n e d plate a f t e r completion of the sub scale test program 5 Develop process for pre forming the i n t e g r a l l y s t i f f e n e d plate Various means of pre forming pockets which should be evaluated include press or r o l l forming and explosive forging of pockets to reduce the amount of material requiring removal by machining or chemical m i l l i n g This study should be done i n i t i a l l y i n scale model and l a t e r i n f u l l scale
142 PRIORITY RATING WORKSHEET CHART P R Q g R A M F A C T O R S P R O G R A M P R O B A B I L I T Y O F S U C C E S S n LOW 2. ⢠H I C H 8 C R I T I C A L P R O B L E M S T O B E S O L V E D Q F E W / N O T TOO P l F F U r U L T Z ⢠S O M E / D I F F I C U L T S J t M A N Y / V E R Y D I F F I C U L T 6 P R O C E S S G R O W T H P O T E N T I A L ) < L I T T L E O R O N D e F l N A B L E O a teC06NliABLE P c r B M T I A L 4- A P P L I C A T I O N S O T H E R T H A N AIR F O R C E ⢠NONE O X S O M E 4 D M A N Y e N E C E S S I T Y F O R A I R F O R C e F U N D I N G ⢠LOW Hifix i N t u s T K V / i i r H C A <3o«r C F F o c r H ⢠EXCUJSl l'e A I R F e U i t F U N P M 6 L I K C L V 14. NEED FACTORS S Y S T E M S P R O B A B I L I T Y H I G H P B O B A B I L l T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y V E R Y H I C H H I A H F A I R L o w F R E C J U E N C Y O F R E Q U I R E M E N T IN ? Y « T E M M S R E THAKI 3 C e M P B I ^ E N T S Z 3 I ^ M P e M E M T S siNdLE COMPONENT oesiGN A L T E R M A T E S No A L T E R N A T e R n C Q E e N ONE A L T E R N A T E S E V E R A L A L T E R N A T E S M A T E R I A L S I M P L I C A T I O N N e w M A T E R I A L P e V t t O f M t N T (LtOt O (VWTEBIAL I M P f t O V E M E M T R E i B D NO P R O B L E M f o U e S C E k l s n g 6 3 3 2 I q 6 3 6 4 o CALCULATE PRIORITY S T E P I S T E P 2 S T E P 3 0 9 US RAW S C O R E S F O R R E F E R e N O I ) COMP0NCMT IH T A B L e S AT t N B OF P A N E L I Z t p e t T W I T H I J A W T O T A L S E N T E R E P M QUMMA&V AT (216MT H i C I R C L E H I G H E S T A A R P R A W S C O R E IN C A C H O T H E R SVSTeM CIRCLE N E X T H I G H E S T I F WITHIN 4 PO\NTS O F TOP S C O R E n âL LOW â L â N U M B E R OF ^ V S T E M S HIAH c i R C L e F R E O U e N C Y D I S T R I B U U O N F A C T O R N U M s e n . O P s y s r e i x i s H I G H S C O R E 8 & U 3 W C I 3 « e M M L E N U M S e R O F S Y S T E M S L O W 0 I 2 RMoee 1 O 1 a 1 4 1 3 1 f 1 7. 1 *f 1 4 â¢3/ 9 ⢠⢠I â¢HI ⢠⢠c ⢠⢠c ⢠⢠[ ⢠⢠[ D C S V S T . H . S AARP RA>M SCORES ⢠⢠p = 3Z T O T A L = ^ 7 PRIORITY
143 TITLE FORMING REFRACTORY ALLOY BODIES OF REVOLUTION CHART PRioRinr J2_ RELATED CAMR CHARTS M A N U F A C T U R I N G R E Q U I R E M E N T Foiming of 6 inch Co 2A inch diameLer hollow hemispherical or conical shapes wi t h i n t e r i o r s t i f f e n i n g f o r nose cone applications from Cb and Mo base alloys for service to 3000 F and from W and Ta alloy s f o r service to 5000 F thicknesses from 0 040 inch to 0 10 inch with tolerance of + 0 10 inch on diameter Forming tubing and cylinders of revo l u t i o n from 2 inch diameter X 3 feet long to 5 feet diameter x 15 foot long and ir r e g u l a r contour ducting up to 15 inch diameter x 5 feet long for combustion chambers d l f f u s e r components ducting and nozzles Forming converging diverging shapes of re v o l u t i o n and hollow annular shells for rocket nozzles ramjet and tu r b o j e t components for service from 2500 F to 3500 F Sheet thicknesses 0 010 inch to 0 125 inch Maximum exposure up to 2 hours per f l i g h t and up to 10 f l i g h t s t o t a l A A R P R E F E R E N C E S E C h o t s £i B C h a I . 81 28c 32a 39c PiFVPii C h n r t t Metal Forming No 2 and No 3 A P P L I C A B L E P R O C E S S HIGH TEMPERATURE SPINNING HIGH ENERGY RATE FORMING HIGH TEMPERATURE DEEP DRAWING or 3 03 14 3 03 09 3 08 00 C o d e S T A T E O F T H E A R T A S S E S S M E N T High Temperature Spinning The high temperature mechanical properties s t i p u l a t e d as AARP charts are i n many instances considerably i n excess of available r e f r a c t o r y metal all o y s For example P&FVP Chart tantalum base a l l o y e x h i b i t i n g 3 percent maximum s t r a i n i n 10 at 3500 F w i t h a t e n s i l e strength of 50 000 p s i at 3000 F A permitted a f t e r 50 hours at 3000 p s i at 4500 F The Ta lOW a approximately 20 minutes at 3500 F when stressed at 6000 psi 4000 psi at 4400 F This a l l o y has a t e n s i l e strength of 17 the elevated temperature strength requirements st i p u l a t e d by al l o y development program is required requirements by the referenced those possessed by cu r r e n t l y No 3 called for a tungsten and hours under a load of 30 000 p s i maximum of 1 percent s t r a i n is Hoy e x h i b i t s 5 percent creep i n and ruptures i n 10 minutes under 000 psi at 3500 F Thus to meet the AARP a s i g n i f i c a n t r e f r a c t o r y Recent developments of arc melted and cast to shape nose cones and other shapes made from hypereutectic carbides of r e f r a c t o r y metals such as columbium tantalum hafnium etc have produced extremely promising r e s u l t s i n that these materials can withstand extremely high heat fluxes and have good thermal shock resistance These new materials should accordingly be evaluated as competitive materials for some of the applications l i s t e d i n the referenced AARP charts Since the hypereutectic r e f r a c t o r y metal carbides are cast to shape i n t e g r a l l y s t i f f e n e d nose cones can be cast i n one piece by appropriate molding and casting techniques High temperature spinning c a p a b i l i t i e s for producing parts of re v o l u t i o n from r e f r a c t o r y metals and alloy s are commercially available today Large tungsten crucibles up to 12 inch diameter have been produced by t h i s method from sheet stock 0 062 inch to 0 090 inch i n t h i c k ness Scaling up t h i s technique for larger hemispherical parts i s not considered a problem from a manufacturing technology standpoint providing adequate sheet material (as to size q u a l i t y and uniformity) i s available Tungsten sheet i s c u r r e n t l y available up to 26 inch width and other r e f r a c t o r y metals and alloys are available i n sheet form up to 44 inch wide The lack of experience to date i n forming conical shapes w i t h small radius heads from r e f r a c t o r y metal sheet precludes a q u a n t i t a t i v e assessment of present day c a p a b i l i t y for such C o n t i n u e ^ ^ i w i e x ^ ^ a g ^ A L T E R N A T E P R O C E S S E S CASTING OF REFRACTORY METAL CARBIDES C o d e 1 02 00
C H A R T 144 STATE OF THE ART ASSESSMEOT. continued parts I n t e r n a l s t l f f e n e r s can be provided i n c y l i n d r i c a l and conical shapes by welding i n the s t i f f e n e r s i n weldable sheet alloys or by chem m i l l i n g or e l e c t r i c a l discharge machining shapes produced from thicker materials Converging diverging shapes i n r e f r a c t o r y metal alloys can be spin formed or made by welding together spin formed segments The more d u c t i l e alloys of columbium and tantalum can be spin formed cold w i t h intermediate annealing steps while the less d u c t i l e molybdenum and tungsten alloys w i l l require hot forming Ir r e g u l a r contour ducting of the more d u c t i l e alloys can be formed at room temperature by a number of high energy rate processes such as explosive forming magnetic or e l e c t r i c a l discharge forming s t a r t i n g from welded or seamless tubular shapes High Temperature Deep Drawing In general deep drawing i s not considered suitable for r e f r a c t o r y metals w i t h low d u c t i l i t y However hemispheres from 4 Inches to 8 inches diameter have been produced by t h i s technique from 0 100 inch t h i c k tungsten The more d u c t i l e columbium and tantalum alloys should e x h i b i t reasonable deep drawing f o r m a b l l i t y High Energy Rate Forming High energy rate forming processes Include among others explosive foiming magnetic and e l e c t r i c a l discharge forming and high v e l o c i t y forging Several of these processes may be advantageously used to produce r e f r a c t o r y metal components of the types c i t e d under Manufac t u r l n g Requirements Four inch diameter hemispherical shapes wi t h flanges have been forged from tuni,sten on Dynapak equipment at 1800 2000 F Also forging of molybdenum by HERF indicates Chat i t may be possible to forge w i t h s t a r t i n g temperatures below the rapid oxidation temperature During the rapid deformation c h a r a c t e r i s t i c of HERF processes adiabaCic heating of the r e f r a c t o r y metal raises i t s temperature such that good flow and die f i l l i n g and shape d e f i n i t i o n occurs The forming of converging diverging shapes of revo l u t i o n i r r e g u l a r contour ducting and segments of annular shells from r e f r a c t o r y a l l o y sheet by means of explosive forming and mag necic and e l e c t r i c a l discharge forming appear feasible especially for the more d u c t i l e columbium and tantalum all o y s C R I T I C A L P R O B L E M S General 1 A v a i l a b i l i t y of suitable sheet material Present maximum sizes of r e f r a c t o r y a l l o y sheet w i l l require piecing together numerous sheet segments by means of fusion welding and some of Che materials of in t e r e s t have r e s t r i c t e d w e l d a b i l i t y and the mechanical properties of weld j o i n t s are not suitable for severe forming operations Mechanical and dimensional tolerances of r e f r a c t o r y a l l o y sheet material are not c u r r e n t l y s u f f i c i e n t l y uniform and vari a t i o n s i n impurity content and processing r e s u l t i n large heat to heat v a r i a t i o n s i n d u c t i l e t o - b r i t t l e t r a n s i t i o n temperature 2 Maintaining uniform heating of sheet material while forming large components poses a c r i t i c a l problem 3 Surfaces of sheet material being hot formed must be protected by i n e r t atmospheres or by oxidation r e s i s t a n t coatings Both approaches pose c r i t i c a l problems i n hot forming large shapes 4 Higher strength sheet materials to meet AARP property requirements would undoubtedly be less formable than current r e f r a c t o r y metal alloys many of which already e x h i b i t r e s t r i c t e d f o r m a b i l i t y Continued on next page
145 C H A R T ^ . , N O J^ll CRITICAL PROBLEMS, continued High Temperature Spinning Spinning sheet less than approximately 0 050 inch thick is beyond the state of the a r t Thinner sheet is d e f i c i e n t i n d u c t i l i t y because of present status of sheet production processes High Temperature Deep Drawing Farts with small radius nose sections are d i f f i c u l t to deep draw without excessive thinning High Energy Rate Forming Rupture of t h i n sections during high energy rate forming P R O P O S E D D E V E L O P M E N T P R O G R A M OBJECTIVE BACKGROUND APPROACH To develop and evaluate competitive methods for forming r e f r a c t o r y a l l o y bodies of revolution including hemispherical and conical nose shapes converging diverging and other symmetrical as we l l as irregular tubular shapes of small to large sizes Due to the li m i t e d past requirements for r e f r a c t o r y components of these configura tions much manufacturing know how is proprietary and the l i m i t i n g forming param eters are to some extent unknown I t i s the general opinion of those engaged i n re f r a c t o r y sheet f a b r i c a t i o n that the shapes could be manufactured by e x i s t i n g hot forming methods with the c r i t i c a l problem being mainly the i n a b i l i t y to obtain sheet with uniform dimensional and physical properties and large enough to form the large sections without segmented construction High v e l o c i t y forging could be used for some configurations and some materials although the r e f r a c t o r i e s have a tendency to rupture under high rates of s t r a i n Success has been reported i n forming similar shapes by spinning deep drawing and high v e l o c i t y forging I n s u f f i c i e n t work has been done to define the size l i m i t s minimum bend r a d i i optimum processing temperatures mechanical properties of formed parts etc Also 0 090 inch sheet i s presently considered the optimum thickness for hot forming since the thinner materials tend to crack The proposed program consists of several phases not a l l of which are w i t h i n the area of manufacturing process development and some of which should necessarily precede the process development stage since they are essential to defining the scope of and tasks to be solved i n the forming studies A Materials Evaluation As pointed out i n the state of the art discussion the development of the cast hypereutectoid r e f r a c t o r y metal carbides offers competitive materials for considers t i o n for nose cone applications exposed to high heat fluxes An evaluation should be made of various competitive materials including the cast carbides as well as refr a c t o r y metal alloys which may have been developed since the AARP report was prepared As part of the materials evaluation program i t w i l l be necessary to determine for those candidate alloys where data does not currentl y e x i s t t h e i r room and elevated temperature mechanical properties including creep and stress rupture as we l l as standard temperatures anistotropy of properties fusion w e l d a b l l l t y and weld j o i n t properties bend d u c t i l i t y and minimum bend radius d u c t i l e to b r i t t l e t r a n s i t i o n temperature and other fracture toughness properties Continued on next page
C H A R T 146 PROPOSED DEVELOPMENT PROGRAM, continued B Design Requirements Before undertaking specific forming development programs t y p i c a l design require ments should be developed for the items l i s t e d In the referenced AARP charts The geometries and sizes of sp e c i f i c components should be specified In s u f f i c i e n t d e t a i l to define the forming problems i n greater d e t a i l than established by the AARP C Forming Program The f i r s t step Involves a survey of base material a v a i l a b i l i t y uniformity of properties and q u a l i t y c o n t r o l effectiveness to provide s t a r t i n g sheet material for the sizes of the various components and forming processes to be Investigated and developed A study should also be made of the problems Involved and the f e a s i b i l i t y of providing i n e r t atmosphere shielding for the various hot forming processes the a v a i l a b i l i t y and p r a c t i c a b i l i t y of oxidation res i s t a n t coatings which can provide adhesion and protection during hot forming and i n achieving and maintaining uniform heating of the work piece and i f necessary the t o o l i n g during hot forming Problems Involved In the scaling up to fabricate the largest components should also be evaluated Typical r e f r a c t o r y metal parts Involving both nose cone and tubular shapes (symmetrical and irr e g u l a r contours) should then be fabricated by the appropriate processes and problems involved i n contamination removal chemical m i l l i n g or e l e c t r i c a l discharge machining should be Investigated F i n a l l y the mechanical properties of formed parts should be determined to evaluate the influence of the forming operations on the material properties
147 PRIORITY RATING WORKSHEET CHART PRQgjpAM FACTORS P R O S R A M P R O B A B I L I T Y O F S U C C E S S a L O W 2 M O D E R A T E 5 ⢠HIAH 8 C R I T I C A L P R O B L E M S TO B E S O L V E D ⢠F E W / N O T TOO DIFFICULT Z H S O M E / D I F F I C U L T 3 a M A N Y / V E R Y D I F F I C U L T 6 P R O C E S S G R O W T H P O T E N T I A L in L I T T L E O R U N D E F I N A B L E O a i Z E M f i N l l A B L E P O T B M T I A L 4 A P P L I C A T I O N S O T H E R T H A N AIR F O R C E n NONE O f i S O M E 4 D MANY e N E C E S S I T Y F O R A I R F O R C E F U N O I N Q ⢠L w H aH iNius e v / O T H c a 6o»r E F F a r li- ft ixeocHATE - s c r i c Brtetx omet. Coatees e a txeiasive AIR F « £ t F U M P H S U K E L W I* . Pa NEED FACTORS S Y S T E M S P R O B A B I L I T Y HI<3H P B O B A B I T Y F A I R P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y V E R Y H I i ' H F A I R L o w F R E a i / E N C Y OF R E Q U I R E M E N T IN S Y S T E M MORE THAN 3 C O M P O N E N T S 4 3 C O M P O N E N T S S i N f l L E C O M P O N E N T D E S I G N A L T E R N A T E S No A L T E B N A T E R W E S E E N ONE A L T E R N A T E S E V E R A L A L T E R N A T E S M A T E R I A L S I M P L I C A T I O N New M A T E m O L (X.V LOPUCNT S C O O MATERIAL i M P f t O V t M E M T E E i B D NO P R O B L E M F o R E s e e i J CALCULATE PRIORITY 8 RAW SCo«£S FOR EACM REFceeNCCD COMPONENT IN T A B L E S AT E N D OF PANEL R t P O t T U i l rH 12A to Tav \ L S E N T E R E P IN <3vlMMAeV AT eisM- A A R P KA*i S C O R E S II |] I S Y S T M S A 3a f> 3e,0) l ^ t o [g&l I II I A3b i^nnizDQ </i>0) riigi I II ^ I ^ I I /i<^ifi)\^\ 1Ì ^ 1 ^ 1 I </6 (3) r i n I 11 11 11 I A t/hfy) rai 1 1 II II I SZ'x 1 ^ 1 II 1Ì 1Ì I ^^^^^ S T E P I S T E P 2 n = 3 S -C I R C L E H I G H E S T A A R P R A W S C O R E IN EACH OTHER S Y S T E M C I R C L E N E X T H I G H E S T S C O R E I F W I T H I N 4 P O I N T S N U M B E R OF S V S T E M S H i d H O F T O P S C O R E »> Z L O W 3 _ S T E P 3 C I R C L E F R E Q U E N C Y D I S T R I B U T I O N F A C T O R f B E L O W t s y s r t M s 2 H art 3 <L M O U NUMISeR O F S Y S T E M S L O W 0 I 2 R M o e t 1 0 1 a I 4 1 1 1 3 1 f 1 z 1 ⢠⢠⢠C I â 1 1 â 1 1 â 1 1 â 1 1 â I I 11 I I I I I I I ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠T O T A L PRIORITY
14b TITLE FORMING OF SUPERINSULATION FOR LARGE CRYOGENIC TANKA<S C H A R T P R I O R I T Y JUL R E U T E D CAMR CHARTS M A N U F A C T U R I N G R E Q U I R E M E N T Forming superinsulation consisting of mul t i p l e layers of r e f l e c t i v e f o i l separated by low thermal conductivity spacers A A R P R E F E R E N C E S B C h a t P4FVPS Charts A P P L I C A B L E P R O C E S S Code WRAPPING LAYERS OF SUPERINSULATION MATERIAL AROUND TANKAGE S T A T E O F T H E A R T A S S E S S M E N T A number of superinsulation materials systems have been developed for a p p l i c a t i o n to spacecraft tankage to insure long term space storage of cryogenic propellents While these systems d i f f e r i n d e t a i l they generally involve the use of mul t i p l e layers of highly r e f l e c t i v e f o i l (aluminum mylar) separated from each other by low thermal conductivity spacers The NRC type employs layers of cri n k l e d aluminlzed mylar such that point to point contact i s maintained beCween adjacent layers The Linde type employs sheets of a special low conductivity paper placed between the mylar layers The General Dynamics Convair type employs 1/4 mil mylar aluminlzed on both surfaces w i t h approximately 2 percent of the surface area covered with t u f t s of nylon floe which act as low conductivity separators A l l three of the above Cypes of superinsulation are superior for t h i s purpose Co Lhe pure liiminum r e f l e c c i v e f o i l s and glass f i b e r separators outlined i n Chart B 99 of Volume I I Aerospace Design Requirements MAB 200 M (AAR 2) No forming problems are anticipated w i t h any of the above superinsulaCion maCerials sysComs since the aluminlzed mylar is very drapable and f l e x i b l e as wel l as quite strong The sheets of mylar can be applied i n sequence to bui l d up to any req ired f i n a l thickness or number of p l i e s There are however a number of c r i t i c a l handling and f a b r i c a t i o n prolleras To minimize heat transfer the aluminlzed mylar must be applied under clean room conditions kept free of flng e r s t a i n s o i l stains and foreign materials. Extreme csre must be exercised to avoid crushing compressions and compaction of the multiple layer buildup at a l l attachment points otherwise the heat transfer c h a r a c t e r i s t i c s w i l l be markedly degraded To cover the surfaces of large cryogenic tankage i t w i l l be necessary to adhesively bond adjacent sheets of aluminlzed mylar to obtain a continuous surface over the e n t i r e tank Fabrication problems w i l l also arise i n attaching the layers of superinsulation materials around d i s c o n t i n u i t i e s such as propellent l i n e o u t l e t s flanges and bosses etc ContInued on next page A L T E R N A T E P R O C E S S E S NONE
149- C H A R T . , . N O Ul«> C R I T I C A L P R O B L E M S 1 Handling of large sheets of t h i n f r a g i l e materials and maintaining complete freedom from fingermarks o i l and other foreign material 2 Prevention of compression or compaction of m u l t i p l e layers of superinsulation materials i n areas of attachment to tankage or propellant lines P R O P O S E D D E V E L O P M E N T P R O G R A M OBJECTIVES To investigate problems of design and attachment of superinsulation materials to large tankage having major surface d i s c o n t i n u i t i e s so as to minimize the degrada t i o n i n thermal e f f i c i e n c y APPROACH 1 Review the current state of the a r t as developed by a number of aerospace companies manufacturers of superinsulation material systems and government laboratories 2 Develop and evaluate low conductivity/high strength non-metallie materials (homogeneous or composite) for use i n superinsulation attachment components or structures (This i s a materials development program and should precede the manufacturing phase described below) 3 Develop and evaluate a number of design and attachment methods for applying superinsulation systems to tank surfaces having d i s c o n t i n u i t i e s such as re-entrant propellant l i n e s bosses etc I t i s necessary to Insure that attachment devices do not cause compaction of the superinsulation i n any places (This i s a two phase study the f i r s t consisting of design analysis heat transfer calculations and experimental v e r i f i c a t i o n by laboratory t e s t and the second involving v e r i f i c a t i o n by construction and tes t i n g of a scale model insulated tank) * Inasmuch as material development design and a n a l y t i c a l studies must precede the manufacturing development phase of t h i s program the l a t t e r should be accorded low p r i o r i t y u n t i l the completion of the former phase A number of NASA funded studies have been conducted i n thic
150 PRIORITY RATING WORKSHEET CHART P R O f l R A M P B O B A B I L I T V O F S U C C E S S ⢠LOW 2L ⢠M O D E R A T E 5 Jl( H ICH 8 CRITICAL P R O B L E M S TO B E S O L V E D a F C W / I * T TOO OlfFieULT 2. V S O M e / O I F F l C U t T S a M A N Y / V E R V D I F F I C U L T 8 PROCESS epOWTH P O T E N T I A L L I T T L E OR y U l D E F I N A O L B O a geco&minBte P O T E M T I A L 4- A P P L I C A T I O N S O T H E R T H A N AIR FORCE ⢠NONE O Jt SOME 4 ⢠MANY e NECESSITY F O R AIR F O R C E FUNDING ⢠law HifiH iNiuSTCV/erHfA (Unr spfetr if a ttC£ulsi\ie AiA FoftCt FUMPMa UKSLW 14. P a NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIQH P 8 0 B A 6 I I T Y F A I R P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y V E R Y H I i ' H H I « H F A I R L O W F R E a u C N C y OF R E a u i R E M E N T IM S Y S T E M MSRE THAM 3 C e M P S H E M T S 2 3 C « M P e i 4 e N r S S I N f l L E e o M P e w E N T O C S I S N A L T E R N A T E S No A L T E R N A T e R s E s e E N O N C AUTERNATe S E V r H A L A L T E R M A T e Q M A T B K I A L 9 I M P L I C A r i O N New M A T E R I A L PEVELO(>MeMT Btd D rMTCRlAL 1MPIU>VEMCWT Reoi P KIO P R C Q L E M r K C S C e i d CALCULATE PRIORITY e e as- RAW s c o p e s F O R EACH ISEFCKEMtW C0Mr»»lt»fT M T A B L E S AT ewD o r PAtJEt BtPetT WITH 1>AM T O T B L S E N T E R E P IM AT eifiUT SV.T MS AABP I2A>M SCOWS ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠S7 CZl ⢠⢠I ⢠⢠o o [ ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠n a n S T E P I C I R C L E U I G H C S T A A R P W H S C O R E S T E P 2 IN E A C H en-HER S V S T 6 M C I R C L E N E X T M I O H E S T S C O R E IP V / I T H I N 4 P O t N T S O F T O P S C O R E n N U M B E R e F g y s T E W S HlAH ^ tow ^ S T E P 3 C I R C L E F R E Q U E N C Y D I S T R I B U T I O N F A C T O R f B E L O W t O F S Y S T E M S L O W NUMBeii, 0 1 S V S T « M S a H I G H 3 OR M M L C 0 1 0 1 a I 4 1 < ^ 1 3 1 *f 1 z 1 f 1 4 TOTAL PRIORITY
131 TITLE FORMING THIN SHEET lOTO UROB CORRUOATBD IRRXOUUR SHAPES CHART PRIORITY RBIATBD CAM^^CHARTSi MANUFACTURING REQUIREMENT F o n n l n s t h i n gauge (0 006 tnoh 0 060 I n c h ) a l p h a C l t a n l u n and w a l d a b l e alunlnum a l l o y s lne» locBO l i i e B u l a r l y shaped e o r r u s a c l e n s t l f C e n e d s e e t l o n s w i t h e o l o r a n e e s Bu£fleiently e l o s e to p e r m i t f u s i o n w e l d l n B S e c t i o n s a r e to be used f o r r i g i d aerodynamic l i f t and c o n t r o l s t r u c t u r e s w i t h major a s s e m b l y dimensions ap to 60 f o o t wide by 25 f o o t h i g h by 90 f o o t long A A R P R E F E R E N C E S F rhnrt. I l l B C h n H ^5 papvps chort A P P L I C A B L E P R O C E S S 1 Code BRAKE AND DIE FORMING 1 3 03 01/3 03 10 S T A T E O F T H E A R T A S S E S S M E N T Key requirements st i p u l a t e d Include high resistance to b r i t t l e fracture down to 423 F no s u s c e p t i b i l i t y to H2 embrittlement in T i to +600 F with a b i l i t y to perform up to +200 F for Al and to 600 F for T i and with no 02 impact s e n s i t i v i t y T i t a n i u m and weldable aluminum alloys with good fracture toughness down to 423 F are currently available However T i sheet exhibits O2 Impact s e n s i t i v i t y and t h i n gauge T I sheet should not be employed for O2 and F2 propellant tanks No coatings and surface treatments are available to overcome t h i s O2 Impact s e n s i t i v i t y T I may or may not depending upon surface treatment and condition be susceptible to H2 embrittlement af t e r exposure to gaseous H2 at 600 F Fabrication of conventional type corrugated panels for aerodynamic l i f t and control surfaces from alpha T i and weldable Al alloys i s w i t h i n the present state of the a r t Cor rugated sections can be brake formed from f l a t sheet in t o s t r a i g h t sections and then r o l l formed into desired contours Titanium f a b r i c a t i o n requires a stress r e l i e v i n g operation a f t e r forming Equipment i s available for forming r e l a t i v e l y large parts and individual aerospace firms are curren t l y up grading c a p a b i l i t i e s In a n t i c i p a t i o n of programs such as the SST Conventional f a b r i c a t i o n of some of the more rea d i l y weldable aluminum alloys can be accomplished at ambient temperature however the same equipment used for f a b r i c a t i n g titanium can be used for warm forming aluminum to reduce sprlngback Tooling has been developed by some aerospace firms for corrugating large sheets of titanium wherein the corrugations are formed i n d i v i d u a l l y as the sheet is fed In from the side Spring loaded pads preheat tl^e material ond allow i t to feed into the f i r s t stage die where the corrugation is formed by a combination of bending with some s l i g h t stretching The material is fed progressively through the top and bottom forming dies and then is sized and stress relieved In a f i x t u r e that is e s s e n t i a l l y similar to the o r i g i n a l forming die Sendzlmlr r o l l i n g of t l i n gauge sheet alloys to develop smooth surfaces and one half to one t h i r d commercial AISI thickness tolerances is state of the a r t i n widths up to 48 Inches and t h i s can probably be scaled up to 60 inches without major e f f o r t Continued on next pag A L T E R N A T E P R O C E S S E S NONE Code
152 CHART N O CRITICAL PROBLEMS 1 H a n d l i n g l a r g e sheet segments so as n o t t o f o i m w r i n k l e s creases d i n g s e t c b o t h b e f o r e and a f t e r f o r m i n g and o t h e r p r o c e s s i n g o p e r a t i o n s 2 Trimming edges o f c o r r u g a t e d sheet t o o b t a i n t o l e r a n c e s s u f f i c i e n t l y c l o s e t o p e r m i t f u s i o n v e l d J o i n i n g t o m a t i n g c o r r u g a t e d s e c t i o n 3 A v a i l a b i l i t y o f l a r g e sheet o f d e s i r e d t h i c k n e s s e s and t h i c k n e s s t o l e r a n c e s Smaller sheets can however be f u s i o n welded t o g e t h e r t o form l a r g e sheets p r i o r t o f o r m i n g s i n c e alpha t i t a n i u m and w e l d a b l e aluminum a l l o y s a r e be i n g c o n s i d e r e d 4 T i t a n i u m sheet below a p p r o x i m a t e l y 0 015 Inches t h i c k I s n o t c u r r e n t l y a v a i l a b l e I n o t h e r t h a n m o d e r a t e l y narrow s t r i p 5 Weld q u a l i t y s t a n d a r d s f o r weld J o i n t s I n t h i n sheet must be developed and n o n - d e s t r u c t i v e t e s t methods Improved PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To dev e l o p c a p a b i l i t y f o r f o r m i n g and h a n d l i n g l a r g e t h i n sheet c o r r u g a t e d segments and develop d e s i g n and J o i n i n g p r a c t i c e s t o m i n i m i z e problems I n J o i n i n g l a r g e t h i n sheet segments BACKGROUND Brake and d i e f o r m i n g o f c o r r u g a t e d sheet p r e s e n t no major t e c h n o l o g i c a l problems T h i n sheet o f t i t a n i u m I s a v a i l a b l e down t o a p p r o x i m a t e l y 0 015 Inches t h i c k w h i l e s t r i p I s a v a i l a b l e down t o f o i l t h i c k n e s s e s Aluminum sheet I s a v a i l a b l e I n a l l gauges Larger sheet can be made by f u s i o n w e l d i n g t o g e t h e r s m a l l e r sheet The problems o f h a n d l i n g l a r g e sheet and segments formed from l a r g e sheet t o a v o i d d i s t o r t i o n and damage Increase w i t h s i z e o f the segments and w i t h decrease I n sheet t h i c k n e s s APPROACH I t I s proposed t h a t a number o f m a n u f a c t u r i n g process development programs be I n i t i a t e d t o e x p l o r e a few o f the more c r i t i c a l problems namely t h e h a n d l i n g o f l a r g e t h i n gauge sheet and f a b r i c a t e d p a r t s t o a v o i d d i s t o r t i o n and damage t r i m m i n g o f edges t o c l o s e t o l e r a n c e s t o p e r m i t f u s i o n w e l d i n g and the development o f d e s i g n and J o i n i n g p r a c t i c e s t o m i n i m i z e f a b r i c a t i o n problems The recommended approaches i n c l u d e 1 E v a l u a t i o n o f v a r i o u s s u p p o r t t o o l i n g concepts f o r h a n d l i n g l a r g e t h i n gauge p a r t s d u r i n g and between v a r i o u s p r o c e s s i n g o p e r a t i o n s T h i s should i n c l u d e the c o n s i d e r a t i o n o f s t r l p p a b l e c o a t i n g s on the as r e c e i v e d m a t e r i a l w h i c h remain i n t a c t and adherent d u r i n g t h e f o r m i n g o p e r a t i o n s and w h i c h p r o t e c t the s u r f a c e s f r o m g a l l i n g s c r a t c h i n g and o t h e r damage i n p r o c e s s i n g and h a n d l i n g 2 The t r i m m i n g o f edges o f l a r g e I r r e g u l a r l y shaped c o r r u g a t e d t h i n sheet segments t o p e r m i t f u s i o n w e l d i n g t o a d j a c e n t l a r g e segments may pose f o r m i d a b l e problems A c o n c u r r e n t e v a l u a t i o n s h o u l d be made o f t h e p r a c t i c a b i l i t y o f and p e n a l t i e s a s s o c i a t e d w i t h o v e r l a p p i n g J o i n t s I n t h i n gauge sheet segments where r o l l seams and r e s i s t a n c e or TIG spot welds can be used f o r p r o d u c i n g p r e s s u r e t i g h t J o i n t s i n p l a c e o f f u s i o n welds
153 PRIORITY RATING WORKSHEET CHART P R Q g p A M P A C T Q B S PR06RAM PROBABILITY OF SUCCESS ⢠L O W Z ⢠MODERATE 5 HICH 8 CRITICAL PROBLEMS TO BE SOLVED ⢠FEV^/NOr TOO PIFFUJULT Z SOME/DIFFICULT 3 a MANY/ VERY PIFFICUtT 6 PROCESS GROWTH POTENTIAL ⢠LITTLE OR. UNDEFINABLE O yS. eEC06Nl lABLE POTEMTIAL 4 APPLICATIONS OTHER TWAN AIR FORCE a NONE O ⢠SOME 4 A MANY e NECESSITY FOR AIR FORCE FUNDINQ n LOW HifiH mwiiai/'enten s w r CFFc^r 4. X iM»oceATE - sci»c EFRKLT oTHce souC'ies s ⢠eXCUJSIVE Ain F»A£b FUMpNa UKEL4 12. NEED FACTORS SYSTEMS PROBABILITY HiaH F T J O B A B I L I T Y FAIR PROBABILITY LOW PROBABILITY COMPONENT CRITlCALITY VERY HICH H I A H FAIR Low FREauENCV OF REQUIREMENT IN SYSTEM MABe THAN 3 C0tAP0Ht.m9 -2. 3 COMPeNEwrs SINdLE COMPMIENT DESISN ALTERMATES No ALTERNATE RnEBEEN ONE ALTEIZNATe SEVERAL ALTERMATES MATERIALS IMPLICATION New MATEe.iAL vt-si^of-ttr ilea o rviATCRlAL IMPOOVEMCNT R£a V No PaesLEM Foncsceia 12 14 9 b 3 3 2 I 9 6 3 6 o CALCULATE PRIORITY» e 6 3 ^ RAW SCo«S FOR EACH REFeeeNCCP COMIVNCMT M TABLES AT two o r PANEL WITH 15AI0 ToTttLS ENTCRTP IN SUMMAftV AT S Y S T t f A S STEP I STEP 2 STEP 3 -23 CIRCLE HIGHEST AARP l?AW S C O R E n s IM EACH OTHER SVST6M CIRCLE NEXT HICMEST SCORE IF WITHIM 4 POIMTS OF TOP SCORE «" ^ tow « NUM&ER OF SVtTEMS H l d H CIRCLE FREQUENCY DISTRIBUTION FACTOR f" BELOWt NUMBen. OP sysTCi - is rtwart I SORMMLE NUMSER OF SYSTEMS LOW I 2 RMOCE 1 0 t a 1 4 1 1 1 3 1 »k 1 z 1 «!⢠1 4 AARP RA>M SCORES 2 3 ⢠E ⢠C ⢠⢠[ ⢠o n ⢠⢠c ⢠⢠c ⢠⢠[ ⢠c ⢠⢠TOTAL PRIORITY
154 TITLE FORMING PRESTRESSED STRIP AND COIL FOR REMOTE MANIPULATION ARMS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Design Concept A (B 163a) Forming p r e s c r e s s e d s t r i p of maraging s t e e l b e r y l l i u m copper 8 120 wide 0 008 0 050 t h i c k t o l e r a n c e + 0 0005 l e n g t h s 725 f l a t and deployed i n t u b u l a r shape jnd t i t a n i u m a l l o y s S t r i p i s t o be c o i l e d Design Concept B (B 163c) Forming T shaped beam fr o m t i t a n i u m ( N i t i n o l ) a l l o y w h i c h i s s t o r e a f l a t on c o i l r o l l am leployed as T Beam Dimensions are 2 4 i n w i d t h and h e i g h t by 3O l o n g t h i c k n e s s of s e c t i o n 0 016 + 0 0005 AARP REFERENCES E ChQrts B Char ts . 163a. c P«FVPS C h a r t s . APPLICABLE PROCESS ROLL AND MANDREL FORMING OF PRESTRESSED STRIP AND COIL EXTRUSION OR JOINING OF STRIP SECTIONS BY WELDING OR BRAZING OF T BEAMS STORED FLAT 3 03 07 6 05 00 Code 6 01 00 STATE O F THE ART ASSESSMENT Two concepts o f remote m a n i p u l a t i o n arms are c o n s i d e r e d ( a ) t u b u l a r column formed f r o m p r e s t r a s s e d s t r i p which i s c o i l e d f l a t on a s p o o l and which assumes the t u b u l a r shape upon deployment and ( b ) a T beam s e c t i o n made o f a t i t a n i u m a l l o y h a v i n g the a b i l i t y t o resume p r e v i o u s shapes when undergoing a phase change w i t h change i n t e m p e r a t u r e The T s e c t i o n would be f l a t t e n e d and c o i l e d on a s p o o l passed t h r o u g h a h e a t i n g element and assume the T shape as i t i s deployed S e v e r a l designs of d e p l o y a b l e elements such as booms and antennas have been developed based upon the use o f p r e s t r e s s e d s t r i p m a t e r i a l s w h i c h are c o i l e d f l a t on s p o o l s and which assume l o n g i t u d i n a l or h e l i c a l t u b u l a r shapes upon deployment These desig n s a r e s t a t e o f the a r t and d e v i c e s capable o f d e p l o y i n g booms from 1/2 t o a p p r o x i m a t e l y 3 1/2 i n diameter from s t r i p up t o 10 i n diameter and 0 002 0 005 i n t h i c k n e s s a r e c u r r e n t l y a v a i l a b l e Be Cu and s t a i n l e s s s t e e l are the most commonly used m a t e r i a l s a l t h o u g h o t h e r a l l o y s such as Be N i t i t a n i u m a l l o y s and maraging s t e e l s have been e i t h e r c o n s i d e r e d or e v a l u a t e d f o r t h i s a p p l i c a t i o n S c a l i n g these booms up t o l a r g e r d i a m e t e r s and i n c r e a s e d s t r i p t h i c k n e s s does n o t appear t o i n v o l v e s e r i o u s t e c h n o l o g i c a l d i f f i c u l t i e s and i t i s r e a s o n a b l e t o expect t h a t normal development d u r i n g the time p e r i o d 1965 1975 w i l l a c h i e v e the d e s i r e d g o a l s w i t h o u t the need o<" s p e c i a l a c c e l e i a t i o n Design Concept A . P r e s t r e s s e d s t r i p and c o i l The f o r m i n g o f p r e s t r e s s e d s t r i p w h i c h i s s t o r e d i n c o i l s and Jeployed i n the form o f o v e r l a p p i n g t u b i n g i s c u r r e n t l y s t a t e o f the a r t and d e v i c e s based upon t h i s d e s i g n are c u r r e n t l y b e i n g employed on s p a c e c r a f t and s a t e l l i t e s f o r g r a v i t y g r a d i e n t s t a b i l i z a t i o n antennas ana f o r the deployment o f i n s t r u m e n t a t i o n B e r y l l i u m copper and s t a i n l e s s s t e e l s t r i p up t o a p p r o x i m a t e l y 10 i n w i d t h have been f a b r i c a t e d f o r these purposes Be Cu s t r i p i n the c o l d r o l l e d c o n d i t i o n i s fed t h r o u g h f o r m i n g mandrels w h i c h c u r v e i t i n t o a t u b u l a r shape w i t h up t o 180° o v e r l a p The s t r i p i s then f e d t h r o u g h a f u r n a c e where i t i s aged a t 775 925F f o r 5 15 minutes depending upon s t r e n g t h r e q u i r e m e n t s A f t e r a g i n g the s t r i p i s wound f l a t on a s p o o l i n w h i c h c o n d i t i o n i t i s e l a s t i c a l l y p r e s t r e s s e d When r e l e a s e d from the s p o o l i t assumes the c o i l e d c o n d i t i o n i n w h i c h i t was aged Continued on n e x t page ALTERNATE PROCESSES NONE Code
155 CHART STATE OF THE ART ASSESSMENT, c o n t i n u e d Requirements f o r d e p l o y a b l e s t r i p are h i g h y i e l d and t e n s i l e s t r e n g t h s and h i g h e l a s t i c modulus t o maximize bending and t o r s i o n s t r e n g t h s o f the deployed t u b i n g M a t e r i a l s w h i c h are e i t h e r b e i n g used or e v a l u a t e d f o r t h i s a p p l i c a t i o n I n c l u d e M a t e r i a l Be Cu Be N l Monel 7178 A l 6A1 AV T l 187 N l Maraglng T e n s i l e S t r e n g t h KSI a f t e r aging 185-210 2A5-270 145 190 85 90 175 285 320 D e n s i t y lbs / l n 5 E l a s t i c Modulus E 10^ p s l 301 318 306 102 161 290 18 28 26 10 16 27 Deployable t u b u l a r booms r a n g i n g from a p p r o x i m a t e l y 1/2 i n c h t o 3 1/2 i n c h i n diameter based upon c o l l e d p r e s t r e s s e d s t r i p are c u r r e n t l y b e i n g produced i n l e n g t h s up t o 800 inches w i t h no major t e c h n o l o g i c a l d i f f i c u l t i e s Another development c o n s i s t s o f a p r e s t r e s s e d s t r i p c o l l e d on a s p o o l which when deployed forms a tube w i t h h e l i c a l w i n d i n g o f the s t r i p such t h a t each t u r n o f the h e l i x o v e r l a p s the a d j a c e n t t u r n The l i m i t a t i o n s i n c u r r e n t d e p l o y a b l e booms o f g r e a t l e n g t h f o r use i n g r a v i t y g r a d i e n t s t a b i l i z a t i o n or remote m a n i p u l a t i o n are n o t b a s i c a l l y a t t r i b u t a b l e t o m a n u f a c t u r i n g problems but are e s s e n t i a l l y problems o f d e s i g n m a t e r i a l s e l e c t i o n and m a t e r i a l s p r o p e r t i e s A major problem xn long booms i s due t o d i s t o r t i o n r e s u l t i n g from s o l a r h e a t i n g o f the exposed s u r f a c e and t h e r m a l c o n d u c t i v i t i e s and th e r m a l expansion c h a r a c t e r i s t i c s o f m a t e r i a l s become i m p o r t a n t f a c t o r s Unique d e s i g n f e a t u r e s r a t h e r than m a n u f a c t u r i n g processes are r e q u i r e d t o overcome t h i s d i f f i c u l t y L i k e w i s e i t I s p r i m a r i l y a d e s i g n problem t o develop i n t e r l o c k i n g f e a t u r e s t o p r o v i d e r e q u i r e d a b i l i t y t o c a r r y t o r q u e loads p r o v i d e l e a k t i g h t j o i n t s e t c Design Concept B . T shaped beams s t o r e d f l a t N l T l a l l o y s o f the N l t l n o l types d i s p l a y a "memory based upon phase changes which occur a t o n l y m o d e r a t e l y e l e v a t e d temperatures M a t e r i a l formed a t these temperatures can be f u r t h e r formed a t lower temperatures and th e n r e v e r t t o t h e i r o r i g i n a l shape when heated back t o the o r i g i n a l f o r m i n g temperature The temperature range w i t h i n which these phase changes occur i s m o d e r a t e l y narrow and the s p e c i f i c temperatures are s e n s i t i v e t o c o m p o s i t i o n v a r i a t i o n s Developmental work aimed a t u t i l i z i n g the N l t l n o l a l l o y s i n remote c o n t r o l l e d deployment de v i c e s i s c u r r e n t l y underway a t s e v e r a l f a c i l i t i e s N l t l n o l type a l l o y s are c u r r e n t l y a v a i l a b l e o n l y i n s m a l l m e l t s When c a s t i n t o l a r g e r i n g o t s problems o f chemical inhomogeneity occur and phase changes do n o t take p l a c e a t a c o n s t a n t temperatures Non u n i f o r m i t y o f p r o d u c t widens the temperature range a t which changes occur and can lead t o severe d i s t o r t i o n The a t t a i n m e n t o f s t r i p and sheet t h i c k n e s s t o l e r a n c e s o f + 0 005 i n c h i n the t h i c k n e s s range o f 0 008 i n c h 0 050 i n c h over long l e n g t h s o f s t r i p and sheet o f N l t l n o l type a l l o y s i s beyond c u r r e n t c a p a b i l i t i e s and would r e q u i r e r e f i n e m e n t of sheet r o l l i n g p r a c t i c e s The a c t u a l need f o r such c l o s e t h i c k n e s s c o n t r o l i n sheet f o r d e p l o y a b l e remote m a n i p u l a t i o n arms i s q u e s t i o n a b l e and should be c a r e f u l l y reviewed b e f o r e proceeding w i t h any development program P r e s e n t l y developed non d e s t r u c t i v e t e s t methods w i t h some a d d i t i o n a l a u t o m a t i o n are s u f f i c i e n t f o r the d e t e c t i o n o f f l a w s i n s t r i p and sheet m a t e r i a l No m a n u f a c t u r i n g development program d i r e c t e d toward f a b r i c a t i o n o f the p r o t o t y p e hardware I s necessary on the N l t l n o l type a l l o y s u n t i l the m a t e r i a l problems are r e s o l v e d
156 TITLE FORMING ROUND BAR CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Form f o r g e d b a r s t o c k t o p r o v i d e an e x t r e m e l y d u c t i l e t e n s i l e l o a d i n g bar w i t h end co n n e c t i o n s f o r b e a r i n g i n s t a l l a t i o n t o serve as a drag s t r u t energy absorber i n ground l a n d i n g systems f o r s p a c e c r a f t M a t e r i a l i s a n i c k e l - c h r o m i u m a l l o y bar a p p r o x i m a t e l y 2 diameter x 70 lo n g AARP REFERENCES E Chartf B C h a r t s . 148a PftFVPS C h a r t s . APPLICABLE PROCESS SWAGE AND MACHINE Code 09 04 STATE O F THE ART ASSESSMENT Forming o f a bar o f n i c k e l chromium a l l o y by the a p p l i c a b l e process or the a l t e r n a t e processes i s w e l l w i t h i n t h e s t a t e o f the a r t Machining t o the r e q u i r e d t o l e r a n c e s ] s w h o l l y f e a s i b l e Heat t r e a t m e n t t o achieve the d e s i r e d u n i f o r m p r o p e r t i e s may be d i f f i c u l t No m a n u f a c t u r i n g program i s r e q u i r e d CRITICAL PROBLEMS ALTERNATE PROCESSES ROLL AND MACHINE EXTRUDE OR EXTRUDE AND MACHINE Code 3 01 01 3 09 03
157 TITLE FORMING HONEYCOMB CORE TO SIMPLE (STRAIGHT LINE) CURVATURES CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Honeycomb core must be formed t o s t r a i g h t l i n e element c u r v a t u r e s f o r s k i r t and lar g e i n t e r s t a g e and m t e r t a n k s t r u c t u r e s which c o u l d be e i t h e r c y l i n d e r s or t r u n c a t e d cones and h i g h temperature aerodynamic c o n t r o l s u r f a c e f o r Dimension Core Thickness Forming Radius F o i l Thickness Face Sheet Thickness Panel Size Targe I n t e r s t a g e S t r u c t u r e s 2020 Aluminum Beta T i t a n i u m Adhesive Bonded S i l v e r Brazed 0 5 t o 2 0 0 5 t o A O 10 t o 25 f e e t Less than 30 f e e t Est about 0 001 Same 0 008 t o 0 020 0 005 t o 0 060 L i f t and C o n t r o l Surface D i s p e r s i o n hardened n i c k e l coated S u p e r a l l o y s 5/8 t o 1 0 001 t o 0 005 w i t h +5/ t o l 0 005 t o 0 060 Moderate ( u n s p e c i f i e d ) 1 X 1 up to 3 X 3 AARP REFERENCES F r h n i< 1A9, 188, 267 B C h o i« 8A , 97b, 122c P4FVPS C h o r f APPLICABLE PROCESS Code SANDWICH SLIP ROLL FORMING PRIOR TO BONDING (Temperature as r e q u i r e d by m a t e r i a l ) 3 03 07 STATE OF THE ART ASSESSMENT No problems have been i d e n t i f i e d which are expected Co be beyond the 1970 s t a t e o f the a r t i n f o r m i n g o f honeycomb core i n s i n g l e degree c u r v a t u r e t o the bend r a d i i r e q u i r e d There w i l l be a problem i n o b t a i n i n g core ( f o i l ) t h i c k n e s s t o the + 5 pe r c e n t t o l e r a n c e r e q u i r e d i f t h a t r e quirement i s a c t u a l l y necessary The mechanical p r o p e r t i e s s t i p u l a t e d i n r e f e r e n c e B 97b f o r the beta t i t a n i u m a l l o y are h i g h e r than p r e s e n t l y a v a i l a b l e but progress i n t i t a n i u m a l l o y development i n d i c a t e s a reasonable e x p e c t a t i o n t h a t s u i t a b l e a l l o y s w i l l be a v a i l a b l e i n the 1970 1975 time p e r i o d A l s o the upper temperature l i m i t s l i s t e d i n r e f e r e n c e B 122c f o r d i s p e r s i o n s t r e n g t h e n e d n i c k e l and s u p e r a l l o y s are h i g h e r than p e r m i s s i b l e w i t h c u r r e n t a l l o y s Such a l l o y s as are developed must meet the f o r m a b i l i t y r e q u i r e m e n t s d e s c r i b e d here Bend r a d i i should impose no problem but s p r i n g b a c k may be a f f e c t e d The bend r a d i i f o r the p a r t s r e q u i r e d are q u i t e generous even c o n s i d e r i n g t h a t core t h i c k n e s s can approach 2 t o 4 inches Such s t r a i g h t l i n e bends are p r e s e n t l y made by r o l l f o r m i n g a sandwich pack which c o n t a i n s face sheets and core r o l l e d t o g e t h e r but not bonded Bonding i s performed by adhesive bonding b r a z i n g or d i f f u s i o n bonding as the m a t e r i a l r e q u i r e s a f t e r f o r m i n g Forming may be done e i t h e r h o t or c o l d aluminum I s formed a t room temperature w h i l e o t h e r m a t e r i a l s r e q u i r e hot r o l l f o r m i n p These techniques are adequate unless bend r a d i i decrease are r e q u i r e d or unless complex c u r v a t u r e s Any moderate degree o f s i n g l e or double c u r v a t u r e can be performed by machining the core N u m e r i c a l l y c o n t r o l l e d machines have been developed t o do t h i s j o b e c o n o m i c a l l y However machining t o contour r e s u l t s i n a core whose w a l l are not perpendIcXilar t o the face sheet s u r f a c e T h i s changes the d e s i g n t o some degree which may be n e g l i g i b l e i n l a r g e r a d i u s s t r u c t u r e s No A i r Force funded program i s deemed necessary a t t h i s time ALTERNATE PROCESSES MACHINING as noted above Code 5 01 00
-158- TITLE FORMING COMPLEX SHAPES FROM REFRACTORY METALS AND ALLOYS CHART PRIORITY RELATED CAMR CHARTS o n MANUFACTURING REQUIREMENT Form v a r i o u s complex shapes ( n o t bodies o f r e v o l u t i o n ) from columbiura molybdenum t a n t a l u m and t u n g s t e n a l l o y s as t y p i f i e d by the f o l l o w i n g a C and D shaped l e a d i n g edges w i t h I n t e r n a l s t i f f e n e r s r i b s and d o u b l e t s 2 t o 6 inches i n chord d i r e c t i o n 5 t o 12 Inches i n span d i r e c t i o n 1 t o 3 i n c h nose r a d i i c o ntour t o l e r a n c e +0 010 i n c h T h i c k n e s s o f m a t e r i a l sO 040 i n c h maximum tem p e r a t u r e 3000F t o 4300F b Panels 24 t o 60 inch e s i n s i z e f o r r i g i d aerodynamic l i f t and c o n t r o l s u r f a c e s s t i f fened or sandwich s t r u c t u r e s made from sheet a l l o y s 0 010 i n c h t o 0 10 i n c h t h i c k A l s o i n t e r n a l ] f i t t i n g s frames s t i f f e n e r s e t c formed from e x t r u s i o n s p l a t e and bar up t o 36 inches i n s i z e maximum temperature 2700F c Form t u b i n g and d u c t i n g from Cb and Ta base a l l o y s t u b i n g >0 25 in c h diameter x 0 010 in c h w a l l x 10 f e e t l o n g and d u c t i n g 6 i n c h diameter x 10 f e e t l o n g and 18 i n c h diameter con t o u r s Maximum tem p e r a t u r e 2000F one t o t h r e e years s e r v i c e a t 8000 p s i (maximum creep p e r m i t t e d 1 p e r c e n t ) i n c o n t a c t w i t h m o l t e n a l k a l i m e t a l s d Form t u b i n g f r o m r e f r a c t o r y a l l o v s (Ta and W) t o c o n t o u r s o f bodies o f r e v o l u t i o n and to t a p e r ed l e a d i n g edge s u r f a c e s r o u n d square and o v o i d c r o s s s e c t i o n s T u b i n g 0 125 i n c h t o 1 0 i n c h I D w a l l t h i c k n e s s 0 005 i n c h t o 0 020 i n c h l e n g t h s t o 10 f o o t Maximum tem p e r a t u r e 3000F 5000F AARP REFERENCES E Cho ts i O , 29b.c. 30a. 31a. 40c, 8 C h a t s P4FVPS C h n r t . Forming No 4 and 5 41a. 42a APPLICABLE PROCESS CONVENTIONAL FORMING OPERATIONS INCLUDING BRAKE FORMING JOGGLING ROLL FORMING DIMPLING IffiEP DRAWING CORRUGATING RUBBER PRESS FORMING ETC Code 3 03 00 STATE OF THE ART ASSESSMENT The development o f Improved r e f r a c t o r y m e t a l a l l o y s has progressed t o the p o i n t where the t a r g e t mechanical p r o p e r t i e s o u t l i n e d i n the r e f e r e n c e d AARP Ch a r t s have e i t h e r been a t t a i n e d or w i l l be a t t a i n e d by the 1975 time p e r i o d w i t h normal development The p r i n c i p a l o u t s t a n d i n g p oblem a ea which t I I emalns I s t h a t o f d e v e l o p i n g nd a p p l y i n g h i g h tempe a t u e o x i d a t i o n r e s i s t a n t c o a t i n g s t h a t p e r f o r m r e l i a b l y d u r i n g repeated c y c l e s o f heat and load a p p l i c a t i o n The c o a t i n g o f f a s t e n e r s and weld j o i n t s pose p a r t i c u l a r l y d i f f i c u l t problems W i t h r e s p e c t t o f o r m i n g the v a r i o u s complex shapes o u t l i n e d under "Manufacturing Require ments Che work done under the R e f r a c t o r y M e t a l s Sheet R o l l i n g Programs and summarized i n DMIC Report 231 Summary o f C o n t r a c t o r R e s u l t s i n Support o f the R e f r a c t o r y M e t a l s Sheet R o l l i n g Program 1 December 1966 has demonstrated t h a t C and D shaped l e a d i n g edges and s t i f f e n e d p a n e l s f o r r i g i d aerodynamic l i f t and c o n t r o l s u r f a c e s can be s u c c e s s f u l l y f a b r i c a t e d from r e f r a c t o r y m e t a l a l l o y s o f columbium molybdenum t a n t a l u m and t u n g s t e n C o n v e n t i o n a l t o o l i n g w i t h f o r m i n g done a t temperatures r a n g i n g from room te m p e r a t u r e t o a p p r o x i m a t e l y 2100F was abl e t o s a t i s f a c t o r i l y form r e q u i r e d shapes from sheet m a t e r i a l s o f most o f the a l l o y s i n v e s t i g a t e d P a r t s were l a b o r a t o r y t e s t e d a t e l e v a t e d t e m p e r a t u r e s and a t h i g h n o i s e l e v e l s (up t o 160 db) and f i n a l l y s u c c e s s f u l l y f l o w n on b o t h t h e ASSET and PRIME r e e n t r y v e h i c l e s Mo development program i s recommended t o s a t i s f y t h e r e q u i r e m e n t s o f the r e f e r e n c e d AARP-charts ContInued on next page ALTERNATE PROCESSES NONE Code
CHART -159- STATK-OF-THE ART ASSESSMENT, c o n t i n u e d S t i f f e n e d panels o f r e f r a c t o r y m e t a l a l l o y s have been prepared b o t h by c o n v e n t i o n a l c o r r u g a t i n g and J o i n i n g t e c h n i q u e s and by d i f f u s i o n bonding methods While these coiiq>onents were s u c c e s s f u l l y f a b r i c a t e d a number of problems were encountered as f o l l o w s M a t e r i a l q u a l i t y Edge l a m i n a t i o n s were experienced i n TZM sheet m a t e r i a l d u r i n g punching and b l a n k i n g o f d e t a i l s a t a l l temperatures up t o 600 F Dimpling o f t u n g s t e n sheet c o u l d not be s u c c e s s f u l l y accomplished a t any temperature up t o 1900 F because o f c r a c k i n g or d e l a m l n a t l n g I n a d d i t i o n edge d e l a m l n a t l o n was a l s o experienced i n f o r m i n g channels d u r i n g the c o r r u g a t i o n o f 0 010 I n c h and 0 020 i n c h t h i c k t mgsten sheet m a t e r i a l a t 450 t o 800 F These experiences I n d i c a t e t h a t m a t e r i a l q u a l i t y i s s t i l l a c r i t i c a l problem area and t h a t a d d i t i o n a l development woi k t o produce h i g h q u a l i t y r e f r a c t o r y a l l o y sheet i s r e q u i r e d The most c r i t i c a l problem areas o t h e r t h a n m a t e r i a l q u a l i t y i n s o f a r as fo r m i n g o p e r a t i o n s are concerned i n v o l v e the h e a t i n g and maintenance o f temperature o f r e f r a c t o r y a l l o y s d u r i n g f o r m i n g and the maintenance o f i n e r t atmospheres or o x i d a t i o n p r e v e n t i v e c o a t i n g s d u r i n g f o r m i n g o p e r a t i o n s These problems however r e q u i r e i n d i v i d u a l s o l u t i o n f o r each s p e c i f i c p a r t or component being formed As i n d i c a t e d p r e v i o u s l y the s u c c e s s f u l f a b r i c a t i o n o f many d i f f e r e n t p a r t s under Phase I I I o f the R e f r a c t o r y Metals Sheet R o l l i n g Program has i n d i c a t e d adequate s o l u t i o n o f these problems a t l e a s t f o r the p a r t s which have been made W i t h r e s p e c t t o tube bending o f r e f r a c t o r y a l l o y s (P&FVPS Chart s Nos 4 and 5) t h i s process i s not f u l l y developed a t t h i s time p r i m a r i l y because the p r o d u c t i o n o f r e f r a c t o r y m e t a l t u b i n g i s s t i l l I n the e a r l y stages o f development However the bending o f t u b i n g t o I n t r i c a t e c o n t o u r s i s a w e l l developed technology I n the case o f r e f r a c t o r y a l l o y t u b i n g i t w i l l p r o b a b l y be necessary t o heat the m a t e r i a l t o o b t a i n the r e q u i s i t e d u c t i l i t y f o r a c h i e v i n g s u c c e s s f u l bends While some development work w i l l undoubtedly be necessary i t I s f e l t t h a t normal p r o g r e s s i n t h i s area should be s u f f i c i e n t t o meet requirements w i t h o u t the need f o r e s t a b l i s h i n g A i r Force funded programs aimed s p e c i f i c a l l y a t d e v e l o p i n g t h i s c a p a b i l i t y CRITICAL PROBLEMS NONE
160 TITLE FORMING CLAD METAL PRESSURE VESSELS AND FUEL TANKS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT To produce pressure v e s s e l s and tanks f o r c o n t a i n i n g h i g h e f f i c i e n c y f u e l s u s i n g c l a d m e t a l s t o p r o v i d e i n e r t s u r f a c e s r e s i s t a n t t o c o r r o s i o n or f u e l d e t e r i o r a t i o n Tanks c o u l d be l o c a t e d w i t h i n t h e v e h i c l e s t r u c t u r e or I n e x t e r n a l pods S t r e n g t h - w e i g h t f a t i g u e r e s i s t a n c e and thermal expansion matching o f the c l a d d i n g and base met a l ( s t a i n l e s s s t e e l n i c k e l and c o b a l t a l l o y s t i t a n i u m t a n t a l u m a l l o y s ) are i m p o r t a n t c h a r a c t e r i s t i c s T h i c k nesses o f the b i m e t a l c o u l d range from 0 005 Inches t o 0 093 inches C o r r o s i o n r e s i s t a n t c l a d d i n g c o u l d be a l l o y s o f g o l d p l a t i n u m rhodium or t a n t a l u m AARP REFERENCES E Charts L B C h a r t s . l a P&FVPS C h a r t s . APPLICABLE PROCESS EXPLOSIVE FORM DEEP DRAW STRETCH FORM OR ROLL FORM (process s e l e c t i o n depends on d e s i g n c o n f i g u r a t i o n ) Code 3 08 01 3 03 09 3 03 05 3 03 07 STATE OF THE ART ASSESSMENT Clad m e t a l s i n the t h i c k n e s s range s p e c i f i e d from 0 005 Co 0 093 Inches can be formed by the c o n v e n t i o n a l processes o f e x p l o s i v e f o r m i n g deep drawing s t r e t c h f o r m i n g and r o l l f o r m i n g D e l a m i n a t i o n i s not expected t o be a s e r i o u s problem so lo n g as the f u e l r e s i s t a n t c l a d m a t e r i a l e x h i b i t s adequate d u c t i l i t y f o r the amount o f d e f o r m a t i o n r e q u i r e d by the t a n k d e s i g n which should be t r u e f o r the c l a d d i n g metals i n d i c a t e d above The t h i c k n e s s o f c l a d d i n g i s expected t o remain s m a l l t o minimize the weight p e n a l t y f o r the non s t r u c t u r a l c l a d d i n g The most s e r i o u s problem would be m j o i n i n g r a t h e r than i n f o r m i n g the c l a d m e t a l s An a l t e r n a t e approach would be t o p r o v i d e c o r r o s i o n p r o t e c t i o n t o the assembly by d e p o s i t i o n o f the p r o t e c t i v e metals t o the i n n e r s u r f a c e by p l a t i n g or vapor d e p o s i t i o n Non m e t a l l i c c o r r o s i o n r e s i s t a n t c o a t i n g s can be a p p l i e d by s p r a y i n g and b a k i n g Bladders may a l s o be used t o i n s u l a t e the metal tanks f r o m r e a c t i v e f u e l s P r o t e c t i o n o f f a y i n g s u r f a c e s i f a p a r t o f the tan k d e s i g n w i l l not r e c e i v e adequate p r o t e c t i o n w i t h these approaches and must be avoided i f p r o t e c t i v e m e t a l l i c or non m e t a l l i c c o a t i n g s are a p p l i e d a f t e r t a n k f a b r i c a t i o n No m a n u f a c t u r i n g development program f o r f o r m i n g o f these gauges o f c l a d m e t a l s i s r e q u i r e d CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Code
161- TITLE FORMING LARGE VARIABLE WALL THICKNESS TUBING WITH INTEGRAL END FITTINGS CHART PRIORITY SELATED CAMR CHARTS MANUFACTURING REQUIREMENT Produce t u b u l a r f i t t i n g s f o r major s t r u c t u r a l framework f o r n u c l e a r r o c k e t engine mount Tubing f r o m p r e c i p i t a t i o n s t r e n g t h e n a b l e n i c k e l base s u p e r a l l o y 4 0 10 0 i n c h + 0 03 i n c h I D X 0 050 i n c h 0 150 i n c h + 0 015 i n c h t h i c k w i t h i n t e g r a l end f i t t i n g s and c o o l e d by LH2 A l l c o n n e c t i o n s and t u b i n g t o be LH2 l e a k p r o o f AARP REFERENCES E C h a r t ! . B Cha t$. 172 94 PSFVPS Char ts . APPLICABLE PROCESS FLOW TURNING OR TUBE REDUCING Code 3 03 19 3 09 01 STATE OF THE ART ASSESSMENT Flow T u r n i n g C u r r e n t p r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base s u p e r a l l o y s have room temperature v a l u e s o f (FcyE/p) i n the range o f 1 0 t o 1 2 x 10l3 l b / i n i n the p r e c i p i t a t i o n s t r e n g t h e n e d c o n d i t i o n However when c o l d worked 40 t o 50 p e r c e n t and aged they can achieve v a l u e s up t o a p p r o x i m a t e l y 2 0 x 1013 l b / i n The key d e s i g n requirement o f (FcyE/p) o f 1 8 x 10l3 a t room temperature can be a t t a i n e d by c u r r e n t l y a v a i l a b l e a l l o y s such as I n c o n e l 718 by f l o w t u r n i n g I n the annealed c o n d i t i o n f o l l o w e d by aging I n c o n e l 718 e x h i b i t s e x c e l l e n t combinations of s t r e n g t h d u c t i l i t y and r e s i s t a n c e t o b r i t t l e f r a c t u r e a t 423 F i n the c o l d worked and aged c o n d i t i o n The f o r m i n g of v a r i a b l e w a l l t h i c k n e s s t u b i n g i n the m a t e r i a l and s i z e r e q u i r e d can be done on p r e s e n t i n g a v a i l a b l e equipment by s t a t e of the a r t techniques Large v a r i a b l e w a l l t h i c k n e s s s t a i n l e s s s t e e l tubes have been r e a d i l y f l o w t u r n e d I n t e g r a l f i t t i n g s can be p r o v i d e d by secondary f o r m i n g o p e r a t i o n s i n v o l v i n g swaging f l a r i n g and o t h e r metal g a t h e r i n g o p e r a t i o n s f o l l o w i n g the tube f o r m i n g o p e r a t i o n L i q u i d hydrogen i n l e t and o u t l e t p o r t s can be developed i n the end f i t t i n g s by the p r e v i o u s l y mentioned o p e r a t i o n s By proper combinations of f l o w t u r n i n g and i n t e r m e d i a t e a n n e a l i n g o p e r a t i o n s i t should be p o s s i b l e t o develop s u f f i c i e n t f i n a l c o l d w o r k i n g t o achieve the r e q u i r e d s t r e n g t h l e v e l a f t e r aging While no t c o n s i d e r e d t o pose c r i t i c a l problems some development work I s undoubtedly neces sa r y t o achieve proper balance o f c o l d w o r k i n g i n the t u b u l a r s e c t i o n s o f v a r y i n g w a l l t h i c k n e s s and i n the end f i t t i n g s t o develop r e q u i s i t e s t r e n g t h s throughout the framework members a f t e r the a g i n g heat t r e a t m e n t Normal s t a t e o f the a r t progress i s expected t o p r o v i d e reasonable s o l u t i o i ^ t o t h i s problem Measurement o f the w a l l t h i c k n e s s e s o f v a r i a b l e w a l l Cubing i s not c o n s i d e r e d a problem Tube Reducing Forming of v a r i a b l e c r o s s s e c t i o n s t e e l t u b i n g f o r use i n a i r c r a f t p r o p e l l e r blades i s c u r r e n t p r a c t i c e While tube processes can s u c c e s s f u l l y form the e n t i r e range o f t u b i n g s i z e s l i s t e d o t h e r processes would be more economical and p r a c t i c a b l e f o r s i z e s over 6 i n c h diameter The development of i n t e g r a l end f i t t i n g s would a g a i n be achieved by f l a r i n g swaging and o t h e r secondary processes P r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base a l l o y s e x h i b i t good f o r m a b l l i t y i n the annealed c o n d i t i o n ALTERNATE PROCESSES NONE Code
162 TITLE FORMING LARGE CONICAL AND SPHERICAL SECTIONS FROM SUPERALLOYS AND DISPERSION STRENGTHENED ALLOYS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT A Forming c o n i c a l shapes 24 t o 48 i n c h i n base diameter and 24 t o 36 i n c h h i g h w i t h nose r a d i i o f 8 t o 15 Inches and w a l l t h i c k n e s s o f 0 1 t o 0 2 i n c h from n i c k e l and c o b a l t base s u p e r a l l o y s and d i s p e r s i o n s t r e n g t h e n e d N l Or a l l o y s B Forming s p h e r i c a l shapes up t o 100 square f e e t I n area from n i c k e l and c o b a l t base s u p e r a l l o y s f o r use i n c o n v e c t i o n and t r a n s p i r a t i o n c o oled heat s h i e l d s f a b r i c a t e d f r o m sheet p l a t e and t u b i n g AARP REFERENCES F C h n r K 111 284 B C h d ts 52a 133d e P « F V P S C h n r t . APPLICABLE PROCESS Code 3 03 14 3 03 19 SPIN OR SHEAR SPIN FORMING o r EXPLOSIVE FORMING 3 08 01 STATE OF THE ART ASSESSMENT A Spin or Shear s p i n Forming Spin f o r m i n g o f l a r g e s e c t i o n o f r e v o l u t i o n r a n g i n g f r o m s i m p l e t o complex shapes o f v a r i o u s w a l l t h i c k n e s s e s i n f o i l t o sheet t h i c k n e s s e s from aluminum t i t a n i u m n i c k e l base and s t e e l a l l o y s i s c u r r e n t l y s t a t e o f the a r t "Commercial d i m e n s i o n a l t o l e r a n c e s are a l s o SOA N i c k e l and c o b a l t base s u p e r a l l o y s are v e r y d u c t i l e and formable i n the annealed con d i t i o n a t room and mod e r a t e l y e v a l u a t e d temperatures as are d i s p e r s i o n s t r e n g t h e n e d n i c k e l and N l Cr ( h i g h N l ) a l l o y s No d i f f i c u l t y l a f o r e s e e n i n s p i n n i n g them t o r e q u i r e d shapes C o n i c a l preforms can be r o l l formed and welded from the n i c k e l and c o b a l t base a l l o y s and then s p i n formed t o the r e q u i s i t e c o n t o u r s The d i s p e r s i o n s t r e n g t h e n e d N i and Nl-Cr a l l o y s can be shear s p i n formed from c i r c u l a r b l a n k s r a t h e r t h a n s p i n formed f r o m f a b r i c a t e d preforms s i n c e w e l d i n g may d e s t r o y or m o d i f y the d i s p e r s i o n s t r e n g t h e n e d m t c r o s t r u c t u r e E x p l o s i v e s i z i n g may be employed I f necessary t o achieve f i n a l dimensions No development program i s c o n s i d e r e d necessary O x i d a t i o n r e s i s t a n t c o a t i n g s are p r o b a b l y r e q u i r e d on the f i n i s h e d nose s e c t i o n s a t the upper l i m i t s o f the peak o p e r a t i n g temperature range o f 1800 F 2200 F B The n i c k e l and c o b a l t base s u p e r a l l o y s f o r c o n v e c t i o n and t r a n s p i r a t i o n c o o l e d heat s h i e l d s must meet the f o l l o w i n g mechanical p r o p e r t y r e q u i r e m e n t s ( F t u / p ) 1600 F 2 4 X 105 (F t u / p ) 1800 F i 3 X 105 ( F t y / p ) 1600 F i 3 5 X 10- (E/p) 1600 F a 9 X 10^ Wrought s u p e r a l l o y s meeting these r e q u i r e m e n t s are e i t h e r under development or i n p i l o t p r o d u c t i o n While t h e f o r m a b l l l t y o f these a l l o y s w i l l u n d o u b t e d l y be poorer than t h a t o f the lower s t r e n g t h s u p e r a l l o y s t h e y may be spun or shear spun a t mo d e r a t e l y e l e v a t e d tempera t u r e s where t h e i r f o r m a b l l l t y w i l l be enhanced as compared t o room temperature , Continued on next page ALTERNATE PROCESSES NONE Code
CHART 163 STATE-OF THE-ART ASSESSMEWT. c o n t i n u e d N i c k e l and co b a l t - b a s e s u p e r a l l o y tubes can be bent and bulge formed i n c o m m e r c i a l l y a v a i l a b l e equipment w h i l e h a t ' s e c t l o n or ot h e r shapes o f s t i f f e n e r s can be r o l l formed and r o l l bent i n a v a i l a b l e equipment E x p l o s i v e Forming E x p l o s i v e f o r m i n g o f t h e r e q u i s i t e shapes from welded f l a t sheet or welded c o n i c a l p reforms o f annealed n i c k e l and c o b a l t base s u p e r a l l o y s i s c u r r e n t l y s t a t e o f the a r t The f a c t o r l i m i t i n g e x p l o s i v e f o r m i n g o f the d i s p e r s i o n s t r e n g t h e n e d N i and N l Cr a l l o y s i s sheet s i z e s i n c e s m a l l e r sheet cannot be welded t o g e t h e r t o develop r e q u i r e d sheet s i z e s and prefor m s I n t h e case o f s p h e r i c a l heat s h i e l d components holes f o r the c o o l i n g f l u i d s can be r e a d i l y d r i l l e d or machined i n the m a t e r i a l a f t e r e x p l o s i o n f o r m i n g
164 TITLE FORMING COMPONEKTS OF VERY LARGE STIFFENED TRUNCATED CONICAL BULKHEAD CHART N O PRIORITY RELATED CAMR CHARTS Tm MANUFACTURING REQUIREMENT F a b r i c a t e d components o f v e r y l a r g e ( l e n g t h up t o 600 i n c h major r a d i u s up t o 360 i n c h ) semi-monocoque t r u n c a t e d c o n i c a l s h e l l w i t h e l l i p s o i d a l bulkhead f o r t h r u s t s t r u c t u r e o f nuc l e a r powered space launch v e h i c l e M a t e r i a l s oC t i t a n i u m p r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base s u p e r a l l o y or a u s t e n i t i c s t a i n l e s s s t e e l sheet 0 010 i n c h + 0 001 i n c h t h i c k f o r c o n i c a l s e c t i o n and 0 030 i n c h + 0 001 i n c h t h i c k f o r hat and Zee s t i f f e n e r s AARP REFERENCES E Charts B CI a t 92 P&FVPS Char ts . APPLICABLE PROCESS STRETCH FORMING (BULKHEAD GORE SEGMENTS) BRAKE AND PRESS FORMING (STIFFENERS) Code 3 03 05 3 03 01 STATE OF THE ART ASSESSMENT The key AARP requirements are (F t u / p ) a t room temperature a 8 5 x 10^ i n c h and (FcyE/p) a t room temperature 2 1 8 x 101-3 l b s / i n w i t h good f r a c t u r e toughness a t 423 F and a b i l i t y t o r e s i s t h i g h n e u t r o n and gamma i r r a d i a t i o n from the n u c l e a r r e a c t o r No alpha t i t a n i u m a l l o y i s c i r r e n t l y a v a i l a b l e which can meet the req u i r e m e n t o f 1 8 x 10^3 l b / i n f o r (FcyE/p) but b o t h 60 percent c o l d r o l l e d Type 301 s t a i n l e s s s t e e l and 40 per c e n t c o l d r o l l e d and aged I n c o n e l 718 n i c k e l base s u p e r a l l o y meet the s t i p u l a t e d s t r e n g t h r equirements and have a c c e p t a b l e f r a c t u r e toughness a t l i q u i d hydrogen temperature Both o f these a l l o y s have been e v a l u a t e d a f t e r simultaneous exposure t o a temperature o f 423 F and nuc l e a r i r r a d i a t i o n i n a r e a c t o r and have been found t o e x h i b i t minor d e g r a d a t i o n i n n o t c h toughness (NASA sponsored s t u d i e s conducted by General Dynamics/Ft Worth A e r o j e t General Corp and Lockheed Georgia Cold r o l l e d type 301 and c o l d r o l l e d I n c o n e l 718 have been s u c c e s s f u l l y s t r e t c h formed i n t o gore s e c t i o n s f o r 10 f e e t diameter bulkheads and have been f u s i o n welded Reinforcement lands can be chem m i l l e d ( t h e membrane t h i c k n e s s reduced by e t c h i n g ) or the welds can be r e i n f o r c e d by doubler s t r i p s r e s i s t a n c e spot welded t o e i t h e r s i d e o f t h e f u s i o n w e l d l i n e The w e i g h t p e n a l t y i n v o l v e d by the use o f doubler s t r i p s I s r e l a t i v e l y minor Hat and Zee s t i f f e n e r s can be brake or press formed from annealed or q u a r t e r hard c o l d r o l l e d Type 301 s t a i n l e s s s t e e l and from annealed or s l i g h t l y c o l d r o l l e d or overaged I n c o n e l 718 By the use o f the above d e s c r i b e d m a t e r i a l s I t w i l l n o t be necessary t o heat t r e a t any o f the s k i n and s t l f f e n e r elements r e q u i r e d f o r t h i s component The major problem a r i s e s from the f a c t t h a t a v a i l a b l e sheet s i z e s n e c e s s i t a t e the p i e c i n g t o g e t h e r o f a l a r g e number of sub elements Due t o the s t r i n g e n t t h i c k n e s s t o l e r a n c e o f + 0 001 i n c h i t w i l l be necessary t o employ Sendzimir c o l d r o l l e d sheet w h i c h i s c u r r e n t l y l i m i t e d t o a maximum w i d t h o f a p p r o x l m a t e l y 60 inches Standard f o r m i n g procedures and equipment are c u r r e n t l y a v a i l a b l e and developed f o r f o r m i n g a l l o f the components l i s t e d as r e q u i r e d f o r the v e r y l a r g e t r u n c a t e d c o n i c a l s h e l l and bulkhead No i n s p e c t i o n problems beyond c u r r e n t s t a t e o f the a r t as r e p r e s e n t e d by the manufacture o f A t l a s and Centaur booster v e h i c l e s a r e a n t i c i p a t e d No development program i s proposed ALTERNATE PROCESSES NONE Code
165 TITLE FORMING OF COMPOSITE RADIATION SHIELDING MATERIALS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Produce s p h e r i c a l bulkheads 7 t o 12 f e e t i n diameter from composite m a t e r i a l s which have the combined a b i l i t y t o a t t e n u a t e f a s t neutrons and gamma r a d i a t i o n a t l e v e l s o f 3 X 108 and 3 x 10^ roentgens/hr ( r e p / h r ) a t 10 and 100 f e e t r e s p e c t i v e l y from the r e a c t o r S p e c i f i c s t r e n g t h o f 10^ t o 105 f o r m a t e r i a l s w i t h d e n s i t y o f 10 gms/c c AARP REFERENCES c r l . . ^ , 3 B Charts ? â â P&FVPS Charts â â APPLICABLE PROCESS Code PLASMA SPRAY DEPOSITION 8 02 07 STATE OF THE ART ASSESSMENT C o n s i d e r a b l e work has been done on the development o f composite plasma d e p o s i t e d m a t e r i a l s designed f o r s p e c i f i c d e n s i t y and unique a t t e n u a t i o n c h a r a c t e r i s t i c s f o r photon energy The m a t e r i a l s have been s u c c e s s f u l l y mixed d e p o s i t e d and t h e r m a l l y d e n s i f i e d t o produce p a r t s w i t h s t r u c t u r a l i n t e g r i t y Most o f t h i s work i s h i g h l y c l a s s i f i e d and was done f o r the Atomic Energy Commission T h i s technique would r e q u i r e p h y s i c a l attachment o f hydrogen b e a r i n g m a t e r i a l s f o r n e u t r o n a t t e n u a t i o n however t h i s i s not co n s i d e r e d a problem The plasma technique r e a d i l y lends i t s e l f t o bulkhead s h i e l d i n g s i n c e the m a t e r i a l can be d e p o s i t e d over complex s t r u c t u r a l shapes w i t h i n t e r n a l c o o l i n g t o reasonably c l o s e t o l e r a n c e s I n view o f the c u r r e n t s t a t e o f development o f t h i s process no a d d i t i o n a l development work i s c o n s i d e r e d e s s e n t i a l CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Code
166 TITLE FORMING LARGE CYLINDRICAL SHEET COMPONENTS FOR STIFFENED STRUCTURES CHART N O PRIORITY R E U T E D CAMR CHARTS 70J MANUFACTURING REQUIREMENT 1 Form t h i n sheet and p l a t e i n t o c y l i n d r i c a l s e c t i o n s up t o 30 f e e t diameter 2 Form sandwich panels i n t o c y l i n d r i c a l s e c t i o n s from 3 f e e t t o 30 f e e t i n diameter M a t e r i a l s i n c l u d e medium a l l o y maraging and s t a i n l e s s s t e e l s b e r y l l i u m and t i t a n i u m a l l o y s and n i c k e l and c o b a l t base s u p e r a l l o y s I n sheet and p l a t e form up t o 132 Inches wide and 540 inches long Sheet may be 0 010 i n c h t o 0 075 i n c h i n t h i c k n e s s End i t e m i s a l a r g e s t i f f e n e d c y l i n d r i c a l s t r u c t u r e o f sheet s t r i n g e r or sandwich c o n s t r u c t i o n I n c l u d i n g space c r a f t h u l l s e c t i o n s 20 f e e t i n diameter by 40 f e e t long and r e e n t r y v e h i c l e s up t o 30 f e e t i n diameter AARP REFERENCES E Che »5 212 284 B Cho ts. 107a d 109b 134a b P8FVPS Charts. APPLICABLE PROCESS SHEET NO FORMING REQUIRED PLATE AND SANDWICH MATERIAL ROLL FORMING Code 3 03 07 STATE OF THE ART ASSESSMENT The s t i p u l a t e d mechanical p r o p e r t y r e q u i r e m e n t s f o r the s t e e l s and the b e r y l l i u m and t i t a n i u m a l l o y s are (Ftu/p)RT = 1 X 106 I n c h (Fcy/p)RT = 0 95 x 10^ i n c h and (E/p7RT° 1 x 108 i n c h While those f o r the n i c k e l and c o b a l t base s u p e r a l l o y s are (Ft u / p ) 1800 F = 5 X 10^ i n c h ( F t y / p ) 1800F = 4 x 105 i n c h and (E/o) 1800F = 9 x 10^ i n c h While these r e q u i r e m e n t s are h i g h some p r e s e n t l y a v a i l a b l e a l l o y s come c l o s e t o meeting them and i t i s a n t i c i p a t e d t h a t normal developments by 1975 w i l l r e s u l t i n many more a l l o y s meeting the mechanical p r o p e r t y r e q u i r e m e n t s A t the p r e s e n t time the 10 f o o t diameter p r o p e l l a n t tanks o f the A t l a s and Centaur launch v e h i c l e s are f a b r i c a t e d by General Dynamics Convair from t h i n gauge (0 010 i n c h 0 030 i n c h ) c o l d r o l l e d Type 301 s t a i n l e s s s t e e l having a s t r e n g t h o f 200 000 p s i ( F t u / p ) a p p r o x i m a t e l y 0 89 x 10^ i n c h and e x p e r i m e n t a l c y l i n d r i c a l t a n k segments o f the above type have been f a b r i c a t e d Sendzimlr r o l l i n g m i l l s are a v a i l a b l e which can produce c l o s e t o l e r a n c e c o l d r o l l e d h i g h s t r e n g t h sheet up t o 60 inches i n w i d t h i n l e n g t h s up t o a t l e a s t 1000 f e e t While Chart B 107a r e f e r s t o 132 i n c h wide sheet t o be used f o r the f a b r i c a t i o n o f 20 f o o t diameter h u l l s e c t i o n s i t may be qu e s t i o n e d whether sheet t h i s wide i s a c t u a l l y needed or can be f a b r i c a t e d i n a p r a c t i c a b l e manner W i t h r e s p e c t t o m u l t l w a l l e d c y l i n d r i c a l s t r u c t u r e s (B 107d 134a and 134b) l a r g e t a n k assemblies (15 f o o t t o 20 f o o t i n d i a m e t e r ) are c u r r e n t l y being f a b r i c a t e d by N o r t h American A v i a t i o n under c o n t r a c t t o the A i r Force Rocket P r o p u l s i o n L a b o r a t o r y from d i f f u s i o n bonded t r u s s core sandwich ( J a f f e e metal ) The d i f f u s i o n bonded t r u s s core sandwich m a t e r i a l i s ALTERNATE PROCESSES NONE Continued on next page Code
-167 CHART NO iJ'«3-a« STATB-OF-THE-ART ASSESSMENT, continued produced w i t h i r o n f i l l e r bars which are l e f t I n while the m a t e r i a l I s r o l l formed i n t o c y l i n d r i c a l segments or hot creep formed Into bulkhead gore s e c t i o n s A f t e r forming the s t e e l f i l l e r bars are leached out leaving the eandwich i n the formed co n d i t i o n ready for assembly into the s t r u c t u r e The current A i r Force program has already demonstrated the f e a s i b i l i t y of t h i s approach and t h i s process can produce the required s i z e s of c y l i n d r i c a l tank s e c t i o n s s t i p u l a t e d by the referenced c h a r t s S i m i l a r l y t h i c k e r p l a t e m a t e r i a l can be r o l l formed into c y l i n d r i c a l s e c t i o n s with l i t t l e or no development work required to achieve the d e s i r e d o b j e c t i v e s Based upon the above no development program i s recommended to meet the requirements as o u t l i n e d i n the referenced B and E c h a r t s
EXPLANATION OF C A M R REFERENCES TO S Y S T E M S , COMPONENTS. AND A A R P R A T I N G F A C T O R S NUHBCH 3 9 / 903 I 20s 207 208 tST B-28C d 39c dt Onpeoant 01 03 0 aOSS (or A-3a hjniarioalc cruUe vehicle high eltttuds 01 Ion alclciide end *-3b taypaisoiilc boot glide vehicle atreteglc or tectlcal BBP B-40c Co^neot 01 04 0 IBAODG BOX for A-3b hyperioolc boost glide vehicle ea above BBT B-163a c CoE^nent 04 07 0 »»vin.»ti HulirDUIOR for C-ld artificial apace baae (apace atatlon) BOT B-Ui Coopoiient 01 04 0 UAOIBG EXB for A-2 auper- aonlc high altitude long range aircraft and aiiperaonlc tactical V/8T0L fighter REP Propulalon Bequlrement Porolog No 4 and B-63a Component It 01 0/02 05 0 SOLID BOOST KOTOB CASB for B-la(l) eerth launch ayatem recoverable booater and B-la(2) earth launch spiten - alngle atage to otblt recoverable booster Cooponent 16 01 0 elao for A-4b(l) strategic olsslle - mobile ICBM A-4b(2) strategU Dlsalle - atorable BCBM A-4b(3) strategU mlsslle- apace launched ICBM A-4b(4) atrateglc nlssUe te-entr; system B-2s neer space operatlona spacecraftâ¢space station and B-2c spacecreft ahuttle (nneuvereble) eerth landing system - tangential and B-4a(2) eerth landing system - vertical I ^' ⢠-"« Cooponent 02 04 0 FBBSSUBZ VBSSSl for I B lb(l) space launch ayatem - earth orbit launch and B-lb(2} space launch ayatem - lunar launch SEP B-96 Cosvonant 02 08 0 MAJOB P m D B S (BUIDBAD BNCniS HOUm) for B lb(l) and B-lb(2> syatems as above BBP B-97S STRUCTUBE Cooponent 02 07 0 INTBRSTAGB & ZBTBBIAHX for B lb(l) end B-lb(2) aystema as above BEP B-95b Component 02 04 0 PBISSUBE VESSEL for B-lb(l) and B-lb(2) ayatema as above SYSTEM PROSABlun OOMdONEHI CRITICAUTY FKEaUCNCV OF fttUt IN SmEW\ DESIGN ALTERMA ^ MATCRIOIS IMTUCAnOII AARP RAW scaecs n. B It I t 1 6 3 3 1 1 TOTALS 8 / 9 & tf 9 2 S 6 0 ZÂ¥ o/.oYo, _A Si, 9 2 3 & IX A / 3 0 l > 2Z ft 9 a. ⬠0 0 29 ,i6,p(.e. ,e.iaii 9 9 2 6 V 0 Zl 'i.o.'.o. J'.'A 9 / 6 9 0 *f 9 / 6 ^ 0 zÂ¥ /66IC A</b^) 9 / 6 0 7 i /<./>/0 filbfy e 9 / 6 V 0 Z8 /X 9 / 6 U 0 S2 n. 9 / 0 n . /4 0/ » , Ì Zc 8 « / 6 0 28 8 9 f 0 28 / £ 9 / 0 33. / i t z e i> 29 p2_o<ife ^,1 ,!>,&) 9 *⢠e 0 i> 21 % 6 0 t> 26 eio t o ,s ib(f^ t 0 0 /8 6 z 0 Oipyo ,8 /b(f) & 2 e 0 0 /8 /z 9 / 0 3Z 9 / 0 2^
i -169- E X P U N A T I O N OF C A M R REFERENCES TO S Y S T E M S , COMPONENTS, AND A A R P R A T I N G F A C T O R S I CAMR Cluar NUMBCR EBF B-93 Component 02 06 0 THRUST STRUCTURE FOR B - l b ( l ) space launch systems - e a r t h o r b i t launch and B-lb(2) space launch systems - lunar launch REF B 84 97b Component 02 07 0 XHIBRSXACS & UTTER- TANK STRUCTURES fox B l a ( l ) e arth launch s y stem recoverable booster B l a ( 2 ) eorch launch system s i n g l e stage t o o r b i t recoverable booster B l b ( l ) space launch system e s r t h o r b i t launch and B l b ( 2 } space launch system - lunar launch REF B-122c Cocvtonent 01 01 1/08 01 0 AERODYNAMIC LIFT & CONTROL STRUCTURE RIGID SKIN/HEAT SHIELD f o r B-3a(l) l i f t r e - e n t r y v e h i c l e e s r t h o r b i t a l and B-3s(2) l i f t r e - e n t r y v e h i c l e lunar r e t u r n REF B 28c d 39c d Component 01 03 0 NOSE f o r A 3a hypersonic c i u l s e high a l t i t u d e or low a l t i t u d e v e h i c l e s and A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e s REF B-32o Component 06 01 0 AI& IHISTS 6 DUCTING FOR A-3b hypersonic c r u i s e v e h i c l e s os above RBF Propulsion Requirement Forming No 2 Components 10 06 0 TURBOJET AFTERBURNER COMBUSTION CHAMBER and 10 09 0 TURBOJET HOT QVS DUCTING f o r A-2a supersonic high a l t i t u d e long range chemical fueled a i r c r a f t and A-2c supersonic t a c t i c a l V/STOL f i g h t e r Components 13 01 0 RAMJET DIFFU5ER LSAOING BD(S 13 02 0 RAMJET OIFFUSBR SKINS and 13 03 0 RAMJET COMBUSTION CHAMBER f o r A 3 a ( l ) hypersonic c r u l a e hi«h a l t i t u d e v e h i c l e Cov^onents 14 01 0 LIQUID ROCKET COMBUSTION CHAMBER and 14 02 0 LIQUID ROCKET NOZZLE f o r B-2a(2) near space operations space s t s c i o o and B-2c spacecraft s h u t t l e (maneuverable) Component 16 03 0 SOLID ROCnT NOZZLE f o r A-4b(l) a t r a t e g l c p l e s l l e mobile ICBM A-4b(2) s t r a t e g i c m i s s i l e - mobile ICBM A-4b(2) s t r a t e g i c m i s s i l e scorable ICBM A-4b(3) s t r a t e g i c m i s s i l e space launched ICBM and A-4b(4) s t r a t e g i c r e - e n t r y systeoA REF Propulsion Requirement Forming No 3 Component 16 03 0 SOLID (HYBRID) NOZZLE f o r B 2a near space operations spacecraft and B-2c spacecraft a h u t t l e raanauverable REF B 30a 41a Components 01 01 1 AERODYNAMIC LIFT & COKTROL STRUCTURE RIGID SKIN f o r A 3a hypersonic c r u i s e high a l t i t u d e or low a l t i t u d e v e h i c l e and A-3b hypersonic boost g l i d e v e h i c l e s t r a t e g i c or t a c t i c a l REF B 31a 42a Component 01 01 2 SERODYNAMIC LDT & CONTROL STRUCTURE RIGID SUBSTRUCTURE f o r A 3a and A 3b ve h i c l e s as above REF B-29b c 40c d Component 01 04 0 LEADING EDGE f o r A 3a and A 3b ve h i c l e s aa above Continued on next page it ii SYSTtM PROUBlun OOMdONatT CRITICAIITV FREBUCNCV OF MVCT IN SVSTEM PESIQN ALTERMA £ MATCRIAIS IMniCAT\(ai AARP (2AW 9CORCS n e t \t'\ b i 3 1 1 £ 4-0 IZ 9 / 9 y l> 29 ¥ 9 / J y 0 2/ fitfi7.». .S.lfip} e 9 / 6 0 ¥ 5 f & 0 ^ A T 6 f 0 1 C 0 0 /7 f C 0 Otfi//, fi<x(t) 1% f 0 0 23 01 fiS.o, A^A , 9 s 6 0 tz f 9 1 e. 6 9 9 3 c 0 sz /ep^.o, /),2*, , 12. ^ 2 6 0 3Z /?PfP, A^o. . 12 9 a. « 6 0 JS .fo.09.0 A^.o, . /Z 6 2 IZ 9 2. C (> ss 8 /z 3 e 6 0 3S- /3ot.o fi Safi) 8 9 3 4 ( 0 sz 8 9 3 0 sz ff/o/p pif^C*) /2 6 Z i C 0 3Z e 9 t 6 e a 31 /* 6 Z 0 52 .lff.oX.0. 8 9 3. £ t> 3t y 9 1 i> 2(. ,/tp,S.c /tffbljD 1 i 6 3* ,/:<.«Jo e 9 1 « 0 3o fifi.3.0, /i.<<i>.69 / £ 9 / e> 3* /tpf.p Sill _ 12 A 2 i> 32 9 6 2 <> 28 e /2 3 t) 33 Z 0 e/ei_z 1 ¥ ol0l\ A3J> 9 Z 6 <> is /2 3 C -J* 9 Z C i> 2S
EXPLANATION OF C A M R REFERENCES TO S Y S T E M S , COMPONENTS, AND A A R P R A T I N G F A C T O R S a/A a/3 Continued from precfldlng page BEF Pr o p u l s i o n RequlrenenC Forming No 4 Coiif>onenc 21 01 0 THBBHOBIECTRIC-THBHMIOBI'C DUCTING-FIFING f o r B-la e a r t h launch recoverable boosters S-lb space Isunch systems B 2a near space operations ⢠p s c e c r a f t ond B-2c spacecraft s h u t t l e - moneuverable Components 22 03 0 TUBSOBLBCTRIC HEAT BXCBAHGBRS 22 OS 0 TURBO-ELECTRIC DUCT DIG-PIP DC and 22 06 0 TURBGBLECTRIC TURBIHE CASTING f o r B-lb B-2a and B-2c systems as above EEF Propulsion Requirement Forming No 5 Components 12 U 0 TU&BOBAHJST OlFFUSBR LEADING EDGE f o r A-2a supersonic high a l t i t u d e long range s l r c r s f t A 3 a ( l ) hypersonic c r u i s e v e h i c l e high a l t i t u d e and B-la ea r t h launch recoverable booster Component 13 01 0 RAMJET (M2S) DIFFUSER LEADIKC BDCB f o r A-3a(l) and B l a systems as above Component 18 05 0 GASEOUS POtCR STSTSH KSAT EXCHANGER f o r A-3a hypersonic c r u i s e v e h i c l e s A-4b s t r a t e g i c m i s s i l e s B-le e a r t h launch recoverable boosters B 2a(2) near space operations spsce s t a t i o n and B 2c spacecraft a h u t t l e - maneuverable REF B-107a d Component 02 01 0 SPACECRAFT HULL f o r B 2 a ( l } near space operations e a r t h s a t e l l i t e B 2a(2) near space operations space s t a t i o n B 2a(3} near space operstlons lunar v e h i c l e and B 2c spacecraft s h u t t l e REF B-109b Coiq>onent 02 03 0 SPACBCRAFT EXTBRNAL STRUCTURE f o r B 2 a ( l ) B-2a(2) B 2a(3) and B-2c v e h i c l e s as sbove REF B I l i a b Component 06 05 0/07 01 0 SOUR COLLECTOR STRXTURE/AOTENNA f o r B-2a(l) B-2a(2) B 2a(3) and B 2c systems as sbove REF Propulsion Forming No L Component 16 01 0 SOLID ROCKET CHAMBER f o r B 2a near space operations spacecraft B-2c apocecraft s h u t t l e and B l a ( l ) e a r t h launch recoverable booster // // SYSTeM COMPONCNr CRiricAinr FREQUCNCV OF tUMt IN SVSTEW( DESIGN ALTERMAS MATCRIAIS IMPUCATION AARP RAW SCORES rt 8 4 It 1 6 3 S 1 1 6 4-0 8 3 c i> 30 A .^'<k. n 6 V 0 3* a/«/o, , ^ 2 * , /t 9 S C a 0 3^ *l,t>fe ^ Ì 2e 8 1 3 c T y 0 30 ,»acj.« ,8 , It t ? 6 f 0 3ff /% 9 3 </ 0 3<f 6 3 f( 0 30 AifiAe. A Ik, (t 3 c 0 ? ^ /t f 3 c <> t> 3Â¥ 9JoSe 3 2c 8 3 0 Jo 2toio tlVt /% â¢3 6 0 SÂ¥ / i <i 3 6 ? </ 0 3f 8 9 3 C Â¥ 0 So / i 9 / C> 3Z 8 9 3 A 0 3o t7Jfe ,y/4 8 9 3 0 3e .1.3.01 ,/Ì -?i>.<5/ 8 12 3 0 33 .fXOJO ,^/*. fl / 2 3 c y 0 33 0. .-f*"-. 8 3 £, J 7 ./«J>.s.o, A . / Â¥ 0 J 9 ,/a^o;S_e . g 9 3 0 30 /Z 9 3 c Â¥ O 3Â¥ .-f^A a 6 3 C> -»7 .e>.S.e./.e. A^O) / 2 It S 3 i> 3C IZ /% â¢3 3 .o.i.V.". .S.2»6) V It 3 3 6 i> 38 fit file ,8,2e 9 /» 3 3 6 <> 3Z / 2 a 3 3 e 0 3e of.of-o, jS-ia/if /a c 3 3 c i> 3o 1/ « 3 3 0 2Z 8 4 3 3 t> 26 11 9 3 3 6 0 33 / 2 9 3 3 4 * 33 .8.^f9 9 3 3 C 0 2S 8 9 3 3 0 39 ./l,e/o, ,8H. /Z 9 3 3 6 0 3S 9 9 3 3 6 i> Z9 8 9 1 3 * 37
E X P U N A T I O N OF C A M R REPCRENCES TO S Y S T E M S . COMPONENTS, AND A A R P R A T I N G F A C T O R S OMR eunor NHHMft a/7 a / « M a â¢BP B-la Caqianent 01 07 0 PBESSUIE VESSELS & TANKS f o r A-1 subaoaLc long enduTsnce a i r c z a f c BI7 B 94 Conponent 02 08 0 HkJOR FITTIliGS (BULICHEAD BNCIHB KOUOT) f o r B - l b ( l ) space launch syateffl-earth o r b i t launch and B-lb(2) apace launch syatem lunar launch blF B-99 Cooponent 08 02 0 THBRHAL INSULATION f o r B l b ( l ) and B l b ( 2 ) aystema aa above â¢EF B-49 Component 01 01 1 AERODJNAMIC LIFT h COSTROL STRUCT 1I8E RIGID SKIM f o r A 3c hyperaontc HTOL o r b i t a l v e h i c l e BBF B-52a Coeiponent 01 03 0 NOSE f o r A-3c hyperaonlc HTOL-orbltal v e h i c l e EZF B-133d c Component 08 01 0 HEAT SHIELD f o r B-3b drag e n t r y v e h l c l e a BEFEKBNCES - NONE This CAME chart applies to metal m a t r i x csmpoalcea not considered by AARP i n nnalyals of componenta but CAKS believes they v i l l have wide usago by 1970 1985 U P B 92 Component 02 06 0 THRUST STRUCTURE f o r B l b ( l ) space launch systems e a r t h o r b i t a l launch and B-lb(2) space launch aysteos lunar launch REP B 2 Components 08 03 0 RADIATION SHIELD (NUCLEAR) fo r A 1 subsonic s i r e r a f t BBF B 107a d Component 02 01 0 SPACECRAFT HULL f o r B-2a(l) near spsce operations e a r t h s a t e l l i t e B 2a(2) near space operatlona space a t a t l o n B 2a(3) near space operations lunsr v e h i c l e BBF B 109b Component 02 03 0 SPACECRAFT EITTERNAL STRUCTURE f o r B 2 a ( l ) B 2a(2) B 2a(3) systems above BBF B-134a b Component 01 01 1/01 01 2 AERODYNAMIC LIFT & CONTROL STRUCTURE RIGID SKIN/SUBSTRUCTURE f o r B-3b drag e n t r y v e h i c l e SYSTtM PROeABILin' OOMPONEMT CRITICAUTY FREauCNCV or BJMT IH SYSTEM PESIQN ALTERMA ^ MATCRIAtS IMPUOmON AARP RAW SCORES n e t I t t 6 3 3 1 1 4 6 3 8 6 9 / 6 o 0 ZB .i>:i.ofifi. .B.'liH^ f / 6 o ^ Zo / z / & & d> 37 /%⢠t 6 6 0 Z9 Â¥ 3 6 0 23 Â¥ 9 / 6 o 0 zo /Z / 6 o 0 3/ Afer /a. / 3 a 0 3/ .MAi.0. S.lM) iZ 1 o <> ze 9 1 * e 0 zc e>B.e,3fi A 1. . e 9 / 0 3o ,e?.o.(>o, R.2a.6j 0 t> /a 2. f a 19 ^ 0 d 3S- .etAl.o. ?.2p.Oo V » f o 0 27 .olpiV ?.2«i.0j / a 6 9 0 29 ,e2.c3,o ^,Za,6) fa. 6 9 o t> Zff n ^ o 0 z / ti .o i.l. S^b IZ / 9 0
-173- PANEL ON MATERIAL REMOVAL Members Liaison Mr Francis W Boulger, Chairman Mr Max A Guenther Professor L V Colwell Mr Joseph M e l i l l Dr Michael Field Mr Edward J Hayes Special Advisor Mr K W «talker Flight Propulsion Division General E l e c t r i c Coiiq>any
â¢175- 2 3 MATERIAL REMOVAL A Summary of Problems and Recommendations The Panel on Material Removal considered approximately seventeen potential problems which are expected to be encountered i n aerospace manufacturing between 1970 and 1985 Of that l i s t , twelve had been i d e n t i f i e d by the Aerospace Applications Requirements Panel The other f i v e topics were originated by the Material Removal Panel or by other sources This survey on material removal was confined to problems which were expected to cause d i f f i c u l t y i n prototype production Problems i n economical production of several or large quantities of id e n t i c a l components were not considered Consequently, the Panel makes no recommendations about the d e s i r a b i l i t y of research programs f o r Improving cutting t o o l s , cutting f l u i d s , production practices, machine structures and drive systems, or automation and control systems Never- theless, the Panel on Material Removal would l i k e to emphasize that the ca p a b i l i t i e s of machinlng-control systems, of wrought and of sintered t o o l materials, and production rates of chip-making processes are improving rapidly To a marked extent t h i s progress results from, or was stimulated by, programs sponsored by the U S A i r Force which were endorsed or recommended by previous MAB panels on material removal Because of new design concepts and the wider use of materials with higher strengths or better resistance to heat or oxidation, improvements i n material removal processes are needed Thermal, as well as chemical and mechanical, properties are so closely related that a single development program i s expected to provide the information needed f o r producing a variety of components for dissimilar applications I n such cases, the approach recommended Is to generate information needed f o r optimizing process variables rather than attempt to produce a part or a model Most of the problems anticipated i n material-removal operations i n prototype aerospace components f a l l into the following three categories (a) Processing of unusual materials Many specialists are convinced that fabrication of st r u c t u r a l components from nonmetallic, i n t e r m e t a l l i c , and composite materials w i l l become a major problem A number of d i f f e r e n t kinds of operations may have to be Conducted on a wide va r i e t y of materials or combinations of them The kinds of problems l i k e l y to be encountered would vary among operations (e g , contouring vs hole producing), as well as with the characteristics of the workpiece material Consequently, there are cases where materials should be selected, developed, or categorized before proceeding with development work on removal processes U n t i l the materials and types of operations of greatest Interest are i d e n t i f i e d , development e f f o r t on material removal processes cannot be directed e f f i c i e n t l y
-176- (b) Improvements In processes or equipment I n some cases, the requirements f o r materials and operations have been s u f f i c i e n t l y well characterized that material removal problems are considered l i k e l y Some non-traditional techniques currently employed fo r producing small parts probably can be modified, combined, or scaled-up to meet the manufacturing needs I t appears, however, that sub- s t a n t i a l improvements i n some of the nonmechanical or unconventional processes w i l l be required Therefore, process development programs are recommended for laser d r i l l i n g , chemical m i l l i n g , ultrasonic, electrochemical, and electrodischarging machining Each of the processes offers advantages fo r certain types of operations or classes of materials Some of the anticipated manufacturing requirements are expected to require specialized material-removal equip- ment Those problems stem from d i f f i c u l t i e s i n producing large components to reasonably close tolerances considering the dimensions involved The solutions are expected t o depend on selecting an appropriate material-removal process, using a suitable approach, and then constructing portable equipment by l o g i c a l extensions of engineering knowledge Good cooperation or exchange of information between machine t o o l builders and aerospace manufacturing groups w i l l help i n meet- dimensional requirements Problems i n handling large parts and assemblies may also be troublesome (c) To be solved by advances i n the state of the a r t A few material-removal problems are expected to result mainly from requlrenents f o r producing extremely large parts or components with exceptionally close dimensional tolerances I n such cases, the solution i s expected to come from the normal improvement i n the a r t I n judging the future state of the a r t , the Panel assumed that the growth would continue to be stimulated by government contracts on development of specific end items B Outlook Any material removal operation i s l i k e l y to effect the chemical, physical and mechanical properties near the surface of the workpiece The e f f e c t , which may be either b e n e f i c i a l or harmful depending on the p a r t i c u l a r material-removal practices, i s l i k e l y to be important i n components subjected to unusually severe service conditions The alterations i n the surface layers can appear as cracks, changes i n composition or microstructure, or as residual stresses Such effects may cause d i s t o r t i o n , delayed b r i t t l e fracture, accelerated stress
-177- corrosion or alterations i n fatigue strength Therefore, a development program to study the effects of material-removal practices on alterations i n surface layers, and t h e i r subsequent influence on properties important i n service, i s considered highly desirable Because of t h e i r long history, conventional machining processes are largely based on ar t Perhaps fo r that reason, there i s a noticeable time lapse before manufacturing people apply up-to-date Information and cu t t i n g equipment Nevertheless, industry w i l l soon make wider use of improved machine and cutting tools The r e l a t i v e l y new, higher-carbon types of high-speed st e e l , f o r example, provide advantages i n some applications Their properties are Intermediate between those of the older grades of steel and of cemented carbides so far as cost, toughness, and hardness or strength at elevated temperatures are concerned The wider use of cemented titanium carbide tools, and eventually of other types of materials, should help productivity The application of recent information about r i g i d i t y , v i b r a t i o n and chatter should improve qualit y control Unconventionality, i t s e l f , i s one of the handicaps to quick adoption of non-traditional metal-removal processes Electro- discharge maching has apparently cleared t h i s b a r r i e r and i s quite widely used Applications of electrochemical machining have lagged, p a r t l y because the knowledge necessary fo r designing complex electrodes i s not widespread U t i l i z a t i o n of the process Is growing because i t offers advantages i n quantity production and i n minimizing surface damage Some of the newer nonmechanical processes show promise of solving some vexing problems Electron-beam machining i s established f o r some specialized uses Glow discharges and faster-pulsing, higher-power laser beams may soon prove useful
178 TITLE INTEGRITY OF MACHINED SURFACES CHART PRIORITY 3 / 2 RELATED CAMR CHARTS A U 3 0 0 S e r l e B MANUFACTURING REQUIREMENT To produce components that are free from surface defects or surface layer a l t e r a t i o n s during the machining of aerospace a l l o y s such as high strength s t e e l s high temperature a l l o y s and r e f r a c t o r y a l l o y s AARP REFERENCES E Charts Incorporated references to a l l other 3 0 0 s e r i e s c h a r t s B Charts P&FVPS Charts APPLICABLE PROCESS Code ALL MACHINING PROCESSES 5 0 0 0 0 In a l l machining processes the surface produced i s subject to many a l t e r a t i o n s These machining operations may produce a surface having one or more of the following p l a s t i c deforma tio n m e t a l l u r g i c a l transformation surface hardening or softening high r e s i d u a l s t r e s s macro and microcracks The a l t e r e d surface layer may i n turn a f f e c t the following properties of the component component d i s t o r t i o n fatigue strength s t r e s s c orrosion hydrogen embrittlement Many of the aerospace a l l o y s are p a r t i c u l a r l y s u s c e p t i b l e to surface a l t e r a t i o n s i n machining e g (a) high strength s t e e l s tend to form hard b r i t t l e untempered m a r t e n i s t i c l a y e r s which s e r i o u s l y a f f e c t s t r e s s corrosion and fatigue strength (b) titanium a l l o y s are p a r t i c u l a r l y s e n s i t i v e to s a l t or s t r e s s c orrosion as well as fatigue strength as a function of machining procedures and ( c ) beryllium produces twinning and microcracking i n almost every chip removal machining operation C e r t a i n machining operations such as E l e c t r i c a l Discharge Machining (EDM) i n v a r i a b l y produce severely a l t e r e d surface l a y e r s I f not c o n t r o l l e d EDM and ECM can lower fatigue strength by as much as 50 percent compared to grinding and m i l l i n g Uncontrolled conventional chip producing methods may a l s o reduce the strength by the same order of magnitude CRITICAL PROBLEMS 1 Machined surfaces contain surface a l t e r a t i o n s which may be quite d i f f e r e n t than th base m a t e r i a l 2 The surface a l t e r a t i o n may produce large d i s t o r t i o n s i n components during machininj This i s e s p e c i a l l y so on t h i n sectioned components 3 The surface a l t e r a t i o n i n machining may lead to serious reduction i n c e r t a i n mechanical properties such as fatigue strength and s t r e s s corrosion ALTERNATE PROCESSES NONE Code
- 1 7 9 - CHART PROPOSED DEVELOPMENT PROGRAM OBJECTIVES To study the nature and magnitude of surface and surface layer a l t e r a t i o n s produced i n the machining of aerospace components Also to determine the e f f e c t s of these s u r f a c e a l t e r a t i o n s and of post machining treatments on the mechanical and p h y s i c a l p r o p e r t i e s of the m a t e r i a l BACKGROUND A l t e r a t i o n s i n surf a c e i n t e g r i t y are a common r e s u l t of removing m a t e r i a l from a l l metals including forgings c a s t i n g s and weldments The e f f e c t s are u s u a l l y more pronounced i n high strength components thermal r e s i s t a n t a l l o y s and parts made from b r i t t l e metals A considerable amount of s c a t t e r e d but r e l a t e d work i s being done on t h i s s u b j e c t by industry and on some A i r Force p r o j e c t s A d d i t i o n a l «ork i s recommended however because the topic i s so important I t i s a n t i c i p a t e d that the e a r l y programs be qui t e i n t e n s i v e and that the e f f o r t should taper o f f on follow on programs APPROACH 1 Study the r e l a t i o n between machining parameters and the nature and extent of surface a l t e r a t i o n s i n va r i o u s machining processes S e l e c t important aerospace a l l o y s from m a t e r i a l groups such as high strength s t e e l s n i c k e l and cobalt base high temperature a l l o y s titanium a l l o y s r e f r a c t o r y a l l o y s and be r y l l i u m Important machining operations such as m i l l i n g grinding turning d r i l l i n g EDM ECM and chemical m i l l i n g should be inv e s t i g a t e d With each operation abusive conventional and non abusive conditions should be employed I n the context used here abusive conditions are those which produce a l t e r a t i o n s i n the p r o p e r t i e s of the surface m a t e r i a l 2 The su r f a c e of the workpiece should be examined for surface a l t e r a t i o n s such as m e t a l l u r g i c a l transformation p l a s t i c deformation r e s i d u a l s t r e s s microcracks macrocracks i n t e r g r a n u l a r a t t a c k absorption of chem i c a l l y r e a c t i v e compounds at the workpiece surface e t c 3 I n v e s t i g a t e the underlying f a c t o r s which produce the surface a l t e r a t i o n s i n machining These f a c t o r s are thought to be high temperature gradients p l a s t i c deformation and chemical r e a c t i o n s i n the c u t t i n g zone 4 Determine the r e l a t i o n of surface a l t e r a t i o n s i n machining to mechanical and p h y s i c a l p r o p e r t i e s of the m a t e r i a l The s i g n i f i c a n t p roperties a f f e c t e d should include workpiece d i s t o r t i o n fatigue strength s t r e s s c o r r o s i o n and hydrogen embrittlement 5 I n v e s t i g a t e methods of r e s t o r i n g or improving p r o p e r t i e s by post machining treatments such as heat t r e a t i n g vapor honing and peening
180 PRIORITY RATING WORKSHEET CHART PRQgRAM FACTORS PROflRAM PROBABILITV OF SUCCESS ⢠LOW Z ⢠M O D E R A T E 5 X H I C H 8 CRITICAL PROBLEMS TO BE SOLVED ⢠F K \ ^ / N O T TOO O I F F U J U L T 2 ⢠SOME/DIFFICULT 3 a MANY/ VERY PIFPICUtT S PROCeSS G R O W T H P O T E N T I A L ⢠LITTLE O R UNDEFINABLE O X UeeofiNirABLe poreuTiAL 4- APPLICATIONS OTHER THAN AIR FORCE ⢠N O N E O ⢠SOME 4 J < MANY 0 NECESSITY FOR AIR FORCE FUNOINQ ⢠tow HifiH iinttSt(iv/erHe« <&Mr tFFi>4T 4 ^ MooKATE - smc EFMur oTHce. Ì oaeee9 e a EKfUlsiye A I R F't£t F U M V N A U K C L W 12. p a NEED FACTORS SYSTEMS PROBABILITY HiaH p«WBAei i - i rY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y COMFONENT CRITICALITY VERY H K T H H I « H F A I R L o w FREaUGNCY OF REaUlREMENT IM SYSTEM Mene T H A M 3 C O M P O I ' E M T S 4 3 ceMPeHEiars SiNdLE CfMVONtUT OeSlSN ALTERMATeS No A L T E K N A T E RneecEN OHC At-TEBNATe SEVERAL ALTERMAree MATERIALS IMPLICAriON New MAteRiAL iTevELOfMEMT c e a o MATtRlAL IMPftOVEMeWT REia P No P R o e L E M Foiics'ceid CALCULATE PRIORITY STrP I C I R C L E H I G H E S T AARP RAW SCORE 3£ RAW SCMS FOR EACH REFeeexop CotAVOHltn M TABceS A T tun or PAtiei Rt*>«tT W I T H T!AIO TOTBLS ENreOTP IN Ql/MMAtV AT S Y S T E M S AARP i2A>w scoaes IBB C I 7b Alt QTMSA MATtietAt coAtPtMiMr HAW seone " - 33 CAMU 3te j L j n ] ⢠⢠] ⢠⢠⢠] ⢠⢠⢠⢠⢠] ⢠⢠⢠[ 33 S T E P Z STEP 3 IN E A C H O T H E R S V S T 6 M I F W I T H I N 4 P O I N T S NUMBER c i R C t e OF 6ySTEMS H I A H C I R C L E N E X T H I G H E S T O F T O P S C O R E n >3 LOW > ^ F R E Q U E N C Y DISTRIBUTION FACTOR NUMSen. ov S Y S T C M S Hiari I Z 3 OK MMLE S C O R E B £ U O W i NUMSER OF SYSTEMS LOV^ 0 I 2 itMeae I 0 I I I a I 3 I I 4 7^ J1 nt 33 ^ Z T O T A L PRIORITY
1 8 1 TITLE MACHINING AND TRIMMING OF LARGE STEEL AND TITANIUM ALLOY PARTS CHART N O 20H PRIORITY R E U T E O CAMR CHARTS JflV. 303. ¥iO MANUFACTURING REQUIREMENT Large pressure v e s s e l s up to 50 feet i n diameter 160 feet in length and from 1 to 3 inches w a l l thickness v i l l require c l o s e tolerance trimming prpparatory to welding and post weld cl e a n up of the weld bead The strength l e v e l of the m a t e r i a l s i s a desired y i e l d strength to density r a t i o of 1 6 x 10^ inches for s t e e l or titanium Location and extent of welding w i l l depend on f a b r i c a t i o n technique but w i l l in view of the s i z e l i k e l y require machining and welding at the assembly s i t e High j o i n t e f f i c i e n c i e s are expected of the welds i n d i c a t i n g c l o s e tolerance and f i t requirements for d e t a i l s Longitudinal and c i r c u m f e r e n t i a l j o i n t s are expected on gore c y l i n d e r and ring sections of the motor cases AARP REFERENCES E Charts _ _ _ _ 1 5 0 _ B Char ts . 83a P&FVPS Chorts. Material Removal No 1 APPLICABLE PROCESS MILLING and TURNING (FOR RINGS AND CYLINDERS) Code 5 01 01/5 01 02 STATE OF THE ART ASSESSMENT Present day s t e e l motor cases are considerably smaller The seamless rings and welded c y l i n d e r s are machined on s p e c i a l h o r i z o n t a l lathes C y l i n d r i c a l aluminum sections 33 feet diameter by 138 feet long are inspected and presumably could be machined by turning while set v e r t i c a l l y on p r e c i s i o n rotary tables 34 feet in diameter A double bridge gantry boring and m i l l i n g machine about 40 feet high and 140 feet long has been b u i l t for machining turbines Skate techniques m which the work i s s t a t i o n a r y and a m i l l i n g head i s moved have been used for machining large components This approach has been shown to be f e a s i b l e for machining s t r u c t u r e s from aluminum a l l o y s s t a i n l e s s s t e e l maraging s t e e l and titanium CRITICAL PROBLEMS 1 Tolerance control 1/16 + 1/4 inch on rings 0 + 0 06 inch on gores and c y l i n d e r s 2 S p e c i a l equipment for machining large components 3 Handling and transportation ALTERNATE PROCESSES ELECTROCHEMICAL MACHINING Code 5 03 02
182 CHART PROPOSB) DEVELOPMENT PROGRAM OBJECTIVES To evaluate the f e a s i b i l i t y of machining extremely large components (50 f t Dia X 150 f t long X 1 inch to 2 inch t h i c k ) by s c a l i n g up equipment for skate-mounted m i l l i n g c u t t e r s To determine whether more-sophisticated techniques such as feed back c o n t r o l s w i l l be needed To e s t a b l i s h the lead time needed when equipment c o n s t r u c t i o n i s warranted BACKGROUND P r e s e n t l y procurable equipment i s considered capable of machining components before g i r t h welding The t o t a l weight of the order of 1000 tons and huge dimensions make shipment of the f i n i s h e d case d i f f i c u l t or impossible This may a l s o be true for shorter segments For those reasons equipment for welding machining of segments and of c y l i n d e r s and in s p e c t i o n devices probably w i l l have to be located on the s i t e where the case i s to be used S p e c i a l equipment w i l l have to be constructed I n order to permit machining a f t e r the segments are assembled to form c y l i n d e r s The use of EDM for pocketing operations would minimize problems wi t h r i g i d i t y V arious approaches combine d i f f e r e n t advantages and l i m i t a t i o n s obvious problems are Some of the 1 I n s u r i n g a x i a l alignment of large workpleces and equipment 2 Providing adequate r i g i d i t y to prevent d e f l e c t i o n s of t h i n walled c y l i n d e r (D/t=300) 3 Avoiding d i s t o r t i o n from r e s i d u a l s t r e s s U Poor too l l i f e i n machining hardened s t e e l 5 Slow r a t e s of metal removal compared to the volume of metal to be removed The machine t o o l b u i l d e r s should be h e l p f u l i n designing s u i t a b l e equipment for machining w i t h movable t o o l s APPROACH I t I s recommended that an engineering survey be conducted to determine the best approach to machining huge components and to decide whether any experimental work i s necessary I t may be d e s i r a b l e to develop more r i g i d and s o p h i s t i c a t e d equipment for skate machining i n order to provide more power and f l e x i b i l i t y I f so the equipment should be designed l i k e machine t o o l s not l i k e f i x t u r e s
183 PRIORITY RATING WORKSHEET CHART NO PROfiRAM FACTORS PR06RAM PROBABILITy OF S U C C E S S D LOW Z ⢠MOOeRATE 5 yC HIGH 8 CRITICAL PROBLEMS TO BE SOLVED F E V V / N O T T « ) D I F F I C U L T 2 S O M E / D I F F I C U L T ⢠MANY/ VERY DIFFICULT 8 P R O C E S S gROWTH POTENTIAL & M T r t E OH U N D E F I N A & L E O ⢠eeco6Hizi^»ie poreMriAL 4- A P P L I C A T I O N S O T H E R T H A N A I R F O R C E ⢠NONE O X SOME 4 n MAMY e N E C E S S I T Y F O R A I R F O R C E F U N D I N Q n LOW HifiH i m u S T t t V/crHt* 6 « r C F F C C T 4 ^ IKfOtttATB - Swie BTfotX CT-Mee -SMOtfeS s ⢠ElUrtUSIKE A I R F»ft«t F U M P M 6 UKffLW 14. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIQH PTJOBABIl-ITY IZ FAIR P R O S A e i L l T Y 8 LOW P R O B A B I L I T Y 4 C O M P O N E N T C R I T l C A L I T Y VERY H ICH l i HIAH 9 FAIR & LOW 3 P R E a U E N C y OF R E Q U I R E M E N T IM S Y S T E M MARE THAN 3 CeMPBCENTS 3 4 3 C«MPeMENTS 2 S I N f l L E COMPONENT I DESIGN A L T E R N A T E S No ALTERNATE B W E e e E N <> out A L T E R N A T E 6 S E V E R A L A L T E R U A T C C 3 M A T E R I A L S I M P L l C f l n O N New MATEfclOL PEVtU)?M£*IT StCt 0 6 I^WTtKlAL IMPAOVEMCNT KEia V 4 NO P R o a L E M F o f t e S E E k l O CALCULATE PRIORITY. S V S T t f A S RAW fee. EACH REFCKEMOD CoMreMCMT IN TABLtS AT LNP e r PAUEl RtportT WITH R A W T O T H L S ENTEOCP m <3UMMAItV I Z I S U T 22 AARP RANM SCOWS STEP I S T E P 2 S T E P 3 3 2 CIRCLE HICHEST AARP RAW S C O R E IN EACH OTHER SVSTEM C IRCLE NEXT HIOMEST SCORE IF WITHIN N U M S E R O F iÌ POINTS SVSTEMS H l d H OF TOP S C O R E LOW ^ CiRCUe FREQUENCY DISTRIBUTION FACTOR NUMBen. OP S Y s r e K i s Hi&ri I 2. 3 OR MOCE B E L O W i NUMBER OF S Y S T E M S LOW 0 I 2 RMOtt 1 0 1 a \ 4 1 1 1 3 1 H 1 z 1 i n : ⢠E ] ⢠[ ] ⢠[ O ! [ ⢠⢠^ Â¥ 0 TOTAL PRIORITY
-184- TUIE CLOSE TOI£RANCE lASEK DRILLING OF HOLES IN TUNGSTEN AND DIAMOND CHART PRIORITY _2ZL RELATED CAMR CHAR' ITS MANUFACTURING REQUIREMENT Small ( l e s s than 0 020 Inch) and large diameter holes must be provided w i t h i n very c l o s e t o l e r a n c e s I n tungsten for nose cone a p p l i c a t i o n s Although not s p e c i f i c a l l y I d e n t i f i e d by the AARP Pro p u l s i o n & F l i g h t V e h i c l e Power Subpanel the d r i l l i n g of m u l t i p l e small holes i n l i q u i d rocket f u e l i n j e c t o r s i s a l s o vieued as a c r i t i c a l manufacturing requirement Small diameter wire i s required for composite s t r u c t u r a l m a t e r i a l s f l e x i b l e woven f a b r i c s and shroud l i n e s D r i l l i n g of c l o s e tolerance smooth f i n i s h e d holes i n diamond draw d i e s to s i z e s down to 0 0002 inch + 0 0001 - 0 0000 inch i s necessary for high volume wire production by the drawing technique AARP REFERENCES F rhnr t . 135 302 B C h e n . 6 Id 145b 149b 150b P&FVPS Chart . APPLICABLE PROCESS Code LASER DRILLING (May be followed by mechanical p o l i s h i n g or s i z i n g ) 5 05 04 STATE OF THE ART ASSESSMENT Laser d r i l l i n g i s undergoing extensive e v a l u a t i o n i n i n d u s t r y for d r i l l i n g of very small diameter holes i n hard m a t e r i a l s Diamond d i e s for drawing wire to 0 0004 inch are c u r r e n t l y being produced on a production b a s i s by l a s e r d r i l l i n g There are firms who w i l l now accept c o n t r a c t s for diamond die s e t s for drawing wire to 0 0002 inch The d r i l l i n g of holes to 0 0002 inch i n titanium and tungsten can be accomplished by mech a n l c a l d r i l l i n g Machining r a t e s are extremely slow and depths are l i m i t e d D r i l l i n g at an angl to the s u r f a c e other than normal (90 degrees) g r e a t l y I n c r e a s e s the d i f f i c u l t y and expense Laser d r i l l i n g I s being evaluated as an improved method for overcoming the d e f i c i e n c i e s of the mechanical d r i l l i n g process for d r i l l i n g of small diameter holes The process appears to provide extended c a p a b i l i t y while o f f e r i n g p o t e n t i a l to reduce c o s t s Government funding i s required to a c c e l e r a t e development of the process to achieve the production c a p a b i l i t y required through 1970 No m a t e r i a l development i s required before process development CRITICAL PROBLEMS 1 Surface f i n i s h of l a s e r d r i l l e d holes i s poor 2 Laser d r i l l e d holes are not uniform i n diameter and taper i n length 3 Laser process i s extremely slow for d r i l l i n g m e t a l l i c m a t e r i a l s due to l i m i t e d power of c u r r e n t l a s e r systems 4 Diamond d i e s tend to crack due to high I n t e n s i t y heat of l a s e r beam ALTERNATE PROCESSES MECHANICAL DRILLING ELECTRICAL DISCHARGE DRILLING ELECTRON BEAM DRILLING ELECTROCHEMICAL DRILLING Code 5 01 05 5 04 01 5 04 02 5 03 02
PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To further develop the s t a t e of the a r t of l a s e r d r i l l i n g of holes i n diameters up to 0 020 inch i n tungsten and down to 0 0002 inch i n diamond with emphasis on the smaller s i z e s A d d i t i o n a l m a t e r i a l s used I n components involving small holes should be included i n the program BACKGROUND Fi n e wire draw d i e s and rocket f u e l i n j e c t o r s represent components upon which two Important new technologies are somewhat dependent Both of these items r e q u i r e the c a p a b i l i t y to produce very small p r e c i s e holes i n hard to machine m a t e r i a l s Althougl| I t i s p o s s i b l e to produce holes to the diameters required by mechanical d r i l l i n g the s i z e s represent a range w e l l beyond a p r a c t i c a l a p p l i c a t i o n of the process As a r e s u l t the time required to d r i l l a hole i s ex c e s s i v e the care required i s extreme the r e p r o d u c i b i l i t y or q u a l i t y i s poor and the expense of the parts produced i s great D r i l l i n g at an angle other than normal to the sur f a c e I n c r e a s e s the problems many times The l a s e r d r i l l i n g process i s a p o s s i b l e s o l u t i o n to the problem which o f f e r s the p o t e n t i a l for greater depth of penetration greater accuracy of alignment of holes r e l a t i v e to each other and no apparent problem with d r i l l i n g at angles r e l a t i v e to the surface The l a s e r process a l s o i s p o t e n t i a l l y a much lower cost process which lends I t s e l f to automation APPROACH Two major areas of e f f o r t are required i n order to develop the technology to the l e v e l required through 1970 These are (1) the equipment needs to be improved to i n c r e a s e the power output per energy pulse and to increase the pulse r a t e and (2) the c a p a b i l i t y of the process to d r i l l holes i n high strength/high tempera ture m a t e r i a l s such as titanium tungsten and diamond needs to be evaluated The following approach i s suggested for accomplishing the l a t t e r 1 Evaluate d r i l l i n g r a t e s for va r i o u s m a t e r i a l s and methods for Inc r e a s i n g r a t e other than m o d i f i c a t i o n of the ba s i c power package A vacuum environment surrounding the m a t e r i a l being d r i l l e d might aid i n i n c r e a s i n g d r i l l i n g r a t e Heating of the m a t e r i a l might a l s o be b e n e f i c i a l 2 Determine s i z e range c a p a b i l i t y of the l a s e r d r i l l i n g process (minimum and maximum diameter) 3 Determine d r i l l i n g depth c a p a b i l i t y a Uniformity of dimensions of d r i l l e d hole at va r i o u s depths b Removal of residue 4 Determine c a p a b i l i t y for d r i l l i n g holes at va r i o u s angles to the surface 5 Determine the f e a s i b i l i t y of gang d r i l l i n g f u e l I n j e c t o r s which require thousands of holes i n each part 6 Eva l u a t e f a c t o r s i n f l u e n c i n g surface f i n i s h and diameter uniformity of l a s e r d r i l l e d holes i n various m a t e r i a l s
186 PRIORITY RATING WORKSHEET CHART PROfiRAM FACTORS PROaHAM PROBABILITV OF S U C C E S S a L O W z ⢠MODERATe 5 ) ( HICH 8 CRIT ICAL P R O B L E M S TO B E SOLVED ⢠FCV^/NOT TOO OlfFXCULT Z J5 9< jMe/DIFFICULT a D M A N Y / VERY OlFF ICUtT 6 P R O C E S S G R O W T H P O T E N T I A L D LITTLE OR U N D i F I N A B L E O X (JMoaNiiABte perewTiAL 4 APPLICATIONS OTHER. THAN AIR FORCE ⢠NONE O a SOME 4 X MANY 0 NECESSITY FOR AIR FORCe FUNDINCI ⢠i s w Hifi» iNtuSTav/erHCA 6mT CFFetr 4 M'DCCATE - Some Bmtx entea. ^outees s ⢠Eiu:uJsiVE AiR Fe«et F U M P M A LIKCL<4 M. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH P B O B A e i L I T Y FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T l C A L I T Y V/eHY H I t H HIAH FAIR L o w F R E Q U E N C Y OF REQUIREMENT IN S Y S T E M MOM THAN 3 C0MP>NeUT9 Z 3 C«MP«NeNT3 S I N G L E CeMPONEMT OCStSN A L T E R N A T E S NO ALTERNATE R M E e E E N ONC ALTeHNATE S E V E R A L A L T E R N A T E * M A T E R I A L S I M P L I C A T I O N New MATERIflL V(-StU>ftttHT flea o MATERIAL IMPfWVEMtNT R E A V NO PROSLEM F o a e s e e n it 8 4 14 9 & 3 3 2 I « 3 6 4 o 8 33 RAW F O R EACrt REFieeNfiP COMWNtNT M T A B C U AT two OF PANEL RtPOtT WITH PAIO T C T H L S E N T E R C P m <3KWUA«V AT eifiUT AARP RAVJ SCORES 8 t^{^{zECDCJ CALCULATE PRIORITY. S T E P I C IRCtE HIGHEST A A R P RAW S C O R E m S T E P Z IN EACH OTHER S V S T 6 M C I R C L E NEXT H I C M E S T S C O R E S T E P 3 IF WITHIN 4 P O I N T S NUMBER OF SySTEIHS H ldH C I R C L E O F T O P S C O R E ^ LOW L FRCOUev iCY DISTRIBUTION F A C T O R NuMsen. OS svsreM« Hi&»4 I 2. 3 « K f*'*^ B & L O W i NUM&CR OF S Y S T E M S LOW 0 I 2 timcu. 1 0 1 a I 4 1 3 1 ** 1 z 1 *f 1 <f ⢠⢠⢠⢠] [ ⢠⢠⢠⢠⢠⢠I p = n x f = T O T A L - S2 pRioRiry r
1.U7 TITLE ELECTRO DISCHARGE MACHINING OF SUPERALLOYS REFRACTORY BERYLLIUM TITANIUM AND OXIDATION RESISTANT ALLOYS CHART PRIORITY NO 361 m R E L A T E D C A M R C H A R T S 3 ^ MANUFACTURING REQUIREMENT To machine v a r i o u s types o f s t r u c t u r e s and components f o r aerospace a p p l i c a t i o n s such as s k i n s t r u c t u r e honeycomb and t r u s s c o r e sandwich complex s t r u c t u r a l f i t t i n g s b e a r i n g s and antenna c o l l e c t o r s AARP REFERENCES, , ^ 53 84 229 286 E Charts B r h n r . . 30a c A l a b c U l a b 133d e 134b P&FVPS Charts. APPLICABLE PROCESS ELECTRICAL DISCHARGE MACHINING STATE OF THE ART ASSESSMENT Code 5 04 01 The f e a s i b i l i t y o f m a c h i n i n g o f s o l i d s e c t i o n s o f s u p e r a l l o y s r e f r a c t o r y m e t a l s b e r y l H u m t i t a n i u m and o x i d a t i o n r e s i s t a n t a l l o y s by e l e c t r o d i s c h a r g e and e l e c t r o c h e m i c a l methods has been demons t ra t ed M e t a l r emova l r a t e s need t o be I nc r ea sed and the s u r f a c e f i n i s h e s Improved upon Large Elf t l machines a re c u r r e n t l y capab le o f m e t a l r emova l r a t e s o f 15 25 c u b i c Inches per hour I n these h i g h t e m p e r a t u r e m e t a l s I n d i c a t i o n s a re t h a t f u t u r e v e h i c l e p r o d u c t i o n w i l l be l i m i t e d u n l e s s r a t e s a re I nc r e a se d by two t o t h r e e f o l d H i g h e r amperage s w i t c h i n g methods need t o be deve loped t o Inc r ea se m a c h i n i n g r a t e s E l e c t r o d i s c h a r g e m a c h i n i n g o f r e f r a c t o r y m e t a l sandwich s t r u c t u r e s has p r o v e n t o be v e r y d i f f i c u l t due t o b u r n i n g o f the m e t a l co r e accompanied by e x t r e m e l y h i g h t o o l wear I t has been demons t ra t ed t h a t p o r t a b l e equipment can be used f o r e l e c t r i c a l d i s c h a r g e m a c h i n i n g o f p a r t s or a s sembl i e s t h a t a re t o o l a r g e t o be moved t o a f i x e d machine S u r f a c e s o f the w o r k p i e c e and c u t t i n g t o o l have been c o o l e d by l o c a l Immers ion i n o i l and by s p r a y m i s t s No m a t e r i a l development i s r e q u i r e d b e f o r e process development C R I T I C A L P R O B L E M S 1 M e t a l r emova l r a t e s are t o o low t o s u p p o r t h i g h r a t e p r o d u c t i o n 2 S u r f a c e f i n i s h e s and t o l e r a n c e s a c h i e v e d d e t e r i o r a t e as amperage I s I nc r ea sed t o ach ieve h i g h e r m a c h i n i n g r a t e s 3 E l e c t r o d e wear c o n t r i b u t e s t o p r o b l e m o f s u r f a c e f i n i s h and l o s s o f t o l e r a n c e 4 Heat g e n e r a t e d by c u r r e n t f l o w ( a r c i n g ) must no t a d v e r s e l y a f f e c t the base m a t e r i a l ALTERNATE PROCESSES NUMERICAL CONTROLLED MILLING CONVENTIONAL MILLING ELECTROCHEMICAL MILLING Code 5 01 02 5 01 02 5 03 02
188 CHART NO 3Q7 PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To deve lop methods f o r e l e c t r i c a l d i s c h a r g e m a c h i n i n g o f s u p e r a l l o y s r e f r a c t o r y m e t a l s b e r y l l i u m t i t a n i u m and o x i d a t i o n r e s i s t a n t a l l o y s f o r p r o d u c t i o n o f complex aerospace s o l i d s e c t i o n s and sandwich s t r u c t u r e s BACKGROUND E l e c t r o d i s c h a r g e mach in ing erodes m a t e r i a l by m e l t i n g or v a p o r i z a t i o n o f the me ta l by an e l e c t r i c arc d i s c h a r g e w i t h i n a f l u i d d i e l e c t r i c The ene rgy r e q u i r e d t o remove a g i v e n volume o f any m a t e r i a l i s r e l a t e d t o the m e l t i n g t empera tu re o f the m a t e r i a l Thus the low m e l t i n g t empera tu re m a t e r i a l s such as aluminum are r e a d i l y machined by the p rocess w h i l e the h i g h t empe ra tu r e s u p e r a l l o y s and r e f r a c t o r y m e t a l s are s i g n i f i c a n t l y more d i f f i c u l t T o o l wear i n c r e a s e s sub s t a n t i a l l y w i t h i nc r ea se s i n m a c h i n i n g energy r e q u i r e m e n t s G r a p h i t e i s an e x c e l l e n t m a t e r i a l f o r t o o l s because o f i t s good e l e c t r i c a l c o n d u c t i v i t y and e x t r e m e l y h i g h v a p o r i z a t i o n t empera tu re APPROACH For s o l i d s e c t i o n s o f m a t e r i a l s l i s t e d t o be EDM machined i n i t i a t e d t o work shou ld be 1 I nc r ea se the s i z e o f EDM power s u p p l i e d t o i n c r e a s e m e t a l removal r a t e s 2 Develop improved d i e l e c t r i c m a t e r i a l s f o r a c h i e v i n g improved s u r f a c e f i n i s h e s and t o l e r a n c e s a t the h i g h e r c u r r e n t r e q u i r e m e n t s used f o r f a s t e r m a c h i n i n g 3 Develop improved d i e l e c t r i c f i l t e r i n g and c o o l i n g systems t o i n c r e a s e c u t t i n g r a t e s by keep ing d i e l e c t r i c c l e a n o f m e t a l l i c r e s i d u e w h i l e main t a i n i n g the p a r t and the b a t h a t a c o n t r o l l e d t empera tu re A Develop method f o r removing the h e a t - a f f e c t e d s u r f a c e subsequent t o EDM m a c h i n i n g For sandwich s t r u c t u r e s o f m a t e r i a l s l i s t e d t o be EDM machined I n i t i a t e d t o work shou ld be 1 E v a l u a t e m a t e r i a l s f o r e l e c t r o d e s t h a t w i l l e x h i b i t minimum wear a t i nc r ea sed m e t a l r emova l r a t e s 2 E v a l u a t e mechan ica l methods f o r o s c i l l a t i o i o f e l e c t r o d e s t o d i s t t l b t e wear ac ross t o o l s u r f a c e 3 E v a l u a t e v a r i o u s methods f o i c o o l i n g sandwich core d u r i n g m a c h i n i n g Co p r e v e n t o x i d a t i o n o f m e t a l f o i l and /or h e a t e f f e c t damage 4 O p t i m i z e m a c h i n i n g parameters t o ach ieve good s u r f a c e f i n i s h minimum t o o l wear and good m a c h i n i n g a te For h i g h t empera tu re s e r v i c e a p p l i c a t i o n s such as h y p e r s o n i c ho t s t r u c t res e l e c t r i c a l d i s c h a r g e m a c h i n i n g o f h o l e s m d e t a i l p a r t s o f shapes i n s o l i d s e c t i o n s and o f sandwich s t r u c t u r e s r e p r e s e n t s a d i f f i c u l t m a c h i n i n g p r o b l e m due t o the v e r y h i g h energy r e q u i r e d f o r m a c h i n i n g o f the s u p e r a l l o y s the r e f r a c t o r y m e t a l s a n d ^ o x i d a t i o n r e s i s t a n t a l l o y s
189 PRIORITY RATING WORKSHEET CHART NO 3o7 P R O a R A M PACTORS PR06RAM PROBABILITY OF S U C C E S S O LOW Z ⢠MODERATE 5 ^ HIQH 8 CRITICAL PROBtEMS TO BE SOLVED Q FEVV/NOT TOO DIfFWULT 2. J< 3 0 M E / D I F F I C U L T S D M A N Y / VERY OIFFICULT 8 G R O W T H P O T E N T I A L X L I T T L E 012. U N D E F I N A B L E O ⢠tSeeO^NIlABLE POTEMTIAL 4- OTHER TWAN AIR FORCE NONE O SOME 4 M A N Y e NECESSITY FOR AIR FOgCE FUNDIWa J< LOW HlfiH WtUSTRV/OTHtft < 3 « r CFFOftT 4 ⢠MCDCeATE - Sos*t BratX OTHCK 'S0l>«<!ES e a tt£Lasiy£ A IR Feftet F U M P M S UKCLt YL P R O C E S S APPLICATIONS n X n NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH PROBABI ITY 12 FAia P R O B A B I L I T Y 8 LOW P R O B A B I L I T Y H COMPONENT C R I T I C A L I T Y VERY HICH IZ HIAH 9 FAIR b L o w 3 FREaUENCY OF REQUIREMENT IN S Y S T E M MSRE THAM 3 C0MPa>'eMT9 3 z 3 c e M p e U E n r s 2 S I N G L E COMPWIIEMT I DESIGN A L T C R M A T E S No ALTERNATE R « 6 8 e E M 9 ONE ALTERNATE 6 S E V E R A L ALTERMATEC 3 MATERIALS IMPLICATION New MATEI2.IAL pevtu>f>MeNT e e a o 6 MATCOlflL IMPflOV MEMT Kesi P 4 No P R o c L e M r o c e s e e u o CALCULATE PRIORITY CIRCLE HIGHEST S T E P S T E P I 2 e 2/ RAW SCoUS F O R EACH f2EFceEii<np COMPPNCITT IN T A 6 L « AT two OF PAUeL ^ t P e t T WITH ISAM ToTrtLS ENTEREP IN AT S V S T M S Ale AARP RA\W SCOtteS n = S T E P 3 N U M S E R S F C I R C L E A A R P T?AW S C O R E C I R C L E NEXT H I G H E S T O F T O P S C O R E n 6VSTEWS HldH LOW ^ IN EACH OTHER S Y S T E M IP WITHIN 4 P O I N T S F R E Q U E N C Y DISTRIBUTION F A C T O R I 2. 3 OK MOCLE S C O R E B E L O W i NUMBER O F S Y S T E M S LOW 0 I 2 R MoEe 1 0 1 e I 4 1 1 1 3 1 *f 1 *f 1 4 1 1 n 1 1 1 1 ^ ⢠⢠[ ^ 1 1 1 1 I i i I I II 1 1 1 1 1 1 ⢠⢠n i n ⢠⢠⢠c z rn ⢠⢠⢠[ I Z 1 1 ⢠⢠⢠⢠⢠n ⢠⢠⢠⢠⢠⢠⢠⢠L _ J ⢠⢠⢠⢠n ⢠⢠⢠⢠1 ^ L _ J d l ^ 1 1 ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠1 1 ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠TOTAL PRIORITY
190 TITLE FINISH MACHINING OF NON METALLICS AND COMPOSITES CHART PRIORITY R E L A T E D C A M R C H A R T S MANUFACTURING REQUIREMENT F i n i s h m a c h i n i n g w i l l be r e q u i r e d on r o c k e t nozz l e s t u r b i n e vanes ho t gas v a l v e s ca thodes anodes s e a l s b e a r i n g s and c o m b u s t i o n chamber l i n e r s f a b r i c a t e d f r o m cermets o x i d e s c a r b i d e s s l l i c l d e s and v a r i o u s compos i t e s F i n i s h m a c h i n i n g t o d r i l l c u t shape and t r i m ce ramic or g l a s s pane l s w i l l be r e q u i r e d i n s i z e s up t o 60 Inches w i t h t o l e r a n c e s o f + 0 01 i n c h on t h i c k n e s s e s f r o m 0 125 t o 0 500 i n c h Complex passages may be r e q u i r e d i n Jome p a r t s w i t h d i a m e t e r s down t o 0 02 i n c h and t o l e r a n c e s down t o + 0 0005 i n c h Machined s u r f a c e s must be f r e e o f r e s i d u a l e f f e c t s AARP REFERENCES p r k _ , . . 54 85 260 R rhnr . . 30e 41e 126a b P/lFVPS Chnrt. M a t e r i a l Removal No 3 APPLICABLE PROCESS ELECTRICAL DISCHARGE MACHINING ( f o r conduc t i v e 5 04 Code 01 m a t e r i a l s ) CONVENTIONAL CUTTING ( f o r p l a s t i c c o m p o s i t e s ) ULTRASONIC 5 01 00 ABRASIVE CUTTING ( f o r b r i t t l e n o n c o n d u c t l v e m a t e r i a l s ) 5 07 02 STATE OF THE ART ASSESSMENT C o n d u c t i v e m a t e r i a l s Most c o n d u c t i v e m a t e r i a l s such as cermets can be f i n i s h machined by EIBI or ECM Large s i z e s p r e s e n t problems w i t h p r e s e n t equipment bu t normal p r o g r e s s i n the s t a t e o f the a r t o f those processes and the use o f g r i n d i n g w i l l make I t p o s s i b l e t o produce the p a r t s needed F u t u r e development o f compos i t e s w i t h n o n c o n d u c t l v e c o n s t i t u e n t s may I n t r o duce m a c h i n i n g problems Some r e s e a r c h and development i s b e i n g devo ted t o compos i t e s or c o n d u c t i v e m a t e r i a l s such as t i t a n i u m and aluminum w i t h n o n c o n d u c t l v e f i b e r s or w h i s k e r s o f m e t a l s such as A I 2 O 3 and Zr203 P l a s t i c compos i t e s Most compos i t e s w i t h a m a t r i x o f o r g a n i c p l a s t i c can be f i n i s h e d by c o n v e n t i o n a l c u t t i n g methods G r i n d i n g i s a s u i t a b l e a l t e r n a t i v e f o r those c o n t a i n i n g ha rd and a b r a s i v e c o n s t i t u e n t s such as f i b e r g l a s s r e i n f o r c e d p l a s t i c Composi tes c o n t a i n i n g f i b e r s o f bo ron or c a r b o n or c o n s t i t u e n t s w i t h d i s t i n c t l y d i f f e r e n t c h a r a c t e r i s t i c s Chan the m a t r i x may pose s p e c i a l problems w h i c h have no t been i d e n t i f i e d B r i t t l e , n o n c o n d u c t l v e m a t e r i a l s Sma l l p a r t s have been machined by a b r a s i v e p a r t i c l e b l a s t i n g and by the a c t i o n o f t o o l s v i b r a t i n g a t u l t r a s o n i c f r e q u e n c y w h i l e Immersed I n an a b r a s i v e s l u r r y The l a t t e r method u l t r a s o n i c has been p a r t i c u l a r l y u s e f u l f o r s o l i d non m e t a l l l c s and compounds bu t may n o t work w e l l f o r m e t a l l i c c e r amic c o m p o s i t e s Most o f the a p p l i c a t i o n s have been f o r p r o d u c i n g h o l e s or c a v i t i e s l i t t l e e x p e r i e n c e has been accumula ted i n p r o d u c i n g shaped p a r t s Some a t t e n t i o n has been p a i d t o the p rob lems o f s c a l i n g up the s i z e o f u l t r a s o n i c m a c h i n i n g equipment and u s i n g s p e c i a l s l u r r i e s C o m p a r a t i v e l y l i t t l e s t udy has been devo ted t o a b r a s i v e b l a s t i n g as a m a t e r i a l s removal p rocess CRITICAL PROBLEMS Development o f p l a s t i c compos i tes w i l l have t o precede development o f m a t e r i a l s removal development I n some cases development o f c o n d u c t i v e m a t e r i a l s w i t h n o n c o n d u c t i n g c o n s t i t u e n t s w i l l r e q u i r e p rocess s t u d i e s T h i s i s a l s o t r u e f o r b r i t t l e n o n c o n d u c t l v e m a t e r i a l s bu t some known m a t e r i a l s c o u l d be used f o r s t u d i e s C o n t i n u e d on n e x t page ALTERNATE PROCESSES FOR CONDUCTIVE MATERIALS FOR PLASTIC COMPOSITES FOR BRITTLE NONCONDUCTIVE MATERIALS ECM GRINDING GRINDING ABRASIVE BLAST LIQUID ABRASIVE BLAST DRY GRINDING Code 5 04 01 /5 02 01 5 02 01 5 06 01 5 06 04 5 02 01
191 CHART N O 310 CRITICAL PROBLEMS, c o n t i n u e d C o n d u c t i v e m a t e r i a l s Some compos i tes c o n t a i n i n g m a t e r i a l s w i t h marked ly d i f f e r e n t e r o s i o n c h a r a c t e r i s t i c s or w h i c h are nonconduc to r s may cause t r o u b l e e s p e c i a l l y f r o m the s t a n d p o i n t o f s u r f a c e f i n i s h P l a s t i c compos i tes Development o f compos i tes c o n t a i n i n g f i b e r s w i t h poor c u t t i n g and g r i n d i n g c h a r a c t e r i s t i c s may cause s e r i o u s d i f f i c u l t i e s B r i t t l e , n o n c o n d u c t i v e m a t e r i a l s 1 Some d e s i r a b l e p a r t shapes may no t l end themselves t o u l t r a s o n i c e r o s i o n as c u r r e n t l y p r a c t i c a l 2 Large p a r t s w i l l r e q u i r e f u r t h e r developments I n the s t a t e o f the a r t o f b o t h u l t r a s o n i c m a c h i n i n g and a b r a s i v e c u t t i n g PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To expand the s t a t e o f the a r t o f m a c h i n i n g b r i t t l e n o n c o n d u c t i v e m a t e r i a l s i n shapes and l a r g e s i z e s never needed i n the pas t and o f p l a s t i c ce ramic or m e t a l compos i t e s c o n t a i n i n g b r i t t l e non m e t a l l i c c o n s t i t u e n t s M e t a l l i c compos i tes shou ld a l s o be i n v e s t i g a t e d i n the program because they are n o t covered i n programs d i s c u s s e d e l sewhere BACKGROUND The m a c h i n i n g o f b r i t t l e n o n c o n d u c t i v e components has been l i m i t e d t o s m a l l s p e c i a l i z e d a p p l i c a t i o n s Unusual compounds are o f g r o w i n g i n t e r e s t The e x t e n s i o n o f the use o f such m a t e r i a l s i n t o l a r g e complex shapes w i l l n e c e s s i t a t e new deve lop ments i n m a n u f a c t u r i n g a r t The s u i t a b i l i t y o f a process f o r removing m a t e r i a l and the type o f problems encoun te red depend on the p h y s i c a l and mechan ica l p r o p e r t i e s o f the m a t e r i a l used i n a component APPROACH 1 Survey p e r t i n e n t r e p o r t s and choose the m a t e r i a l s t o be i n v e s t i g a t e d on the ba s i s o f the promise they have demons t ra ted i n r e s e a r c h and development programs Cand i da te m a t e r i a l s m i g h t i n c l u d e some o f the f o l l o w i n g C o n d u c t i v e n i c k e l and c o b a l t base a l l o y s c o n t a i n i n g t u n g s t e n or molybdenum w i r e s f i b e r s or powders Aluminum or t i t a n i u m w i t h w h i s k e r s or f i b e r s o f AI2O3 Zr203 C SiC B Be or b e r y l l i u m w i r e b o r i d e s c a r b i d e s P l a s t i c o r g a n i c p l a s t i c r e i n f o r c e d w i t h g l a s s f i b e r s or w i r e s or f i b e r s o f s t e e l or b e r y l l i u m Nonconduc t ive o x i d e s n i t r i d e s s i l i c o n c a r b i d e BeO + Zr02 g l a s s ce ramics BeO+SiC Th02-fZr02 Zr02-HlgO Zr02-W powder 2 P r o j e c t the knowledge on m a t e r i a l s t o p r e d i c t or a n t i c i p a t e the more l i k e l y t ypes o f a p p l i c a t i o n s and types o f m a t e r i a l problems w h i c h w i l l a r i s e Then choose the types o f r emova l o p e r a t i o n s by m a t c h i n g t h e i r c h a r a c t e r i s t i c s w i t h those o f the m a t e r i a l s and o p e r a t i o n s judged most i m p o r t a n t 3 E v a l u a t e or t e s t c u r r e n t l y a v a i l a b l e EDM c u t t i n g ana g r i n d i n g and u l t r a s o n i c and a b r a s i v e equipment by m a c h i n i n g the types o f m a t e r i a l s judged most c r i t i c a l Of these u l t r a s o n i c m a c h i n i n g seems to have the bes t p o t e n t i a l and s h o u l d r e c e i v e a t t e n t i o n f i r s t 4 Develop s p e c i f i c a t i o n s f o r m a t e r i a l removal processes or necessary equipment
192 PRIORITY RATING WORKSHEET PROGRAM FACTORS PROflRAM PROBABIL ITY OF S U C C E S S P LOW X MODERATE ⢠H\a» CRIT ICAL P R O B L E M S TO B E SOLVED ⢠F E W / N O T TOO D I F F K J U L T ft S O M E / D I F F I C U L T ⢠M A N Y / VERY DIFFICULT P R O C E S S fiROWTH P O T E N T I A L X LITTLE OR UNDEFINABLE D tteOSNIMBLE poreUTIAL APPLICATIONS OTHER THAN AIR FORCE ⢠NONE ⢠SOME X MANY N E C E S S I T Y FOR AIR FORCE FUNOINO n LOW Hifi« imuSTBV/'crHtA Govr S F F C I T it- (neoeeATt - s iwE errctx OTHCA ^oaeees e ⢠ex fu lS lyE A IR feUt F U M D M & U K C L V 12. 2 5 8 Z 3 6 O 4 O e P s NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH P R O S A S I L I T Y F A I R P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T l C A L I T Y VERY HICH H I A H F A I R L O W F R E Q U E N C Y OF REQUIREMENT IN S Y S T E M MORE THAN 3 COMPONENTS z 3 (MiMPeNENrg S I N G L E t^OMPONENT DeS\SN A L T E R N A T E S No A T E B N A T E F b a E s e E M ONE ALTERNATE S E V E R A L A L T E R N A T E * M A T E R I A L S IMPLICATION New MATERIAL pevtLofMENT c e o O MATtClAL IMPROVtMEWT EESl 0 NO PROauEM F o U e S E E N IZ 8 l i 9 S> 3 3 2 1 9 6 3 6 4 o CALCULATE S T E P I S T E P 2 PRIORITY 8 24 R A W S C O R E S F O R E A C H REFEHeNCCP C O M F O N E N T IN TABLES AT tND OF PANEL IJtpOtT W I T H P A I O T O T > L S E N T E R E D ? ru <3UMMAIV tZlSH" CHART S V . . E M . AARP RA>M SCOWS ⢠⢠⢠⢠⢠! ⢠⢠[ u s 5 5 CIRCLE HIGHEST A A R P RAW S C O R E IN EACH OTHER S Y S T E M C I R C L E NEXT H I G H E S T S C O R E IF WITHIN 4 P O I N T S O F T O P S C O R E n NUMBER OF S y s T E M S HldH LOW S T E P 3 C I R C L E F R E Q U E N C Y DISTRIBUTION F A C T O R f B E L O W t Nuroeen. o s y s T t M S H I 2 3 R t*etx. N U M B E R OF S Y S T E M S LOW 0 I 2 RModt 1 0 1 z. 1 4 1 1 1 3 1 4 1 z 1 4 P = n » f = TOTAL = 24^ PRIORITY -ff
193 TITLE SCULPTURING THICK PLATES AND HONEYCOMB PANELS BY CHEMICAL MILLING CHART NO PRIORITY 21L UL RELATED CAMR CHARTS MANUFACTURING REQUIREMENT C a p a b i l i t y xs r e q u i r e d t o f a b r i c a t e c h e m i c a l engines t h r u s t s t r u c t u r e i n t e g r a l l y s t i f f e n e d semi monocoque t r u n c a t e d cones aerodynamic r i g i d s k i n l i f t and c o n t r o l s t r u c t u r e s and a i r i n l e t s and d u c t i n g by s c u l p t u r i n g l a r g e t h i c k f l a t and cu rved p l a t e s up Co 3 inches t h i c k and 48 inches l o n g The t o l e r a n c e s r e q u i r e d are + 0 005 inches M a t e r i a l s t h a t r e q u i r e s c u l p t u r i n g are s u p e r a l l o y s r e f r a c t o r y a l l o y s o x i d a t i o n r e s i s t a n t a l l o y s and be ta t i t a n i u m AARP REFERENCES r r i i n i< 56 87 169 B C h a r t . 30a b c 32a b 41a b c 93 P A F V P < : r h n r t . APPLICABLE PROCESS Code CHEMICAL MILLING 5 03 01 STATE OF THE ART ASSESSMENT S t r u c t u r a l components are now b e i n g made p r i m a r i l y o f aluminum and h i g h s t r e n g t h s t e e l s S c u l p t u r i n g i s now p r i m a r i l y be ing accompl i shed l y c o n v e n t i o n a l or n u m e r i c a l c o n t r o l mach in ing S i m i l a r t e chn iques on s u p e r a l l o y s r e f r a c t o r y a l l o y s o x i d a t i o n r e s i s t a n t a l l o y s and beta t i t a n i u m are p o s s i b l e a t v e r y slow r a t e s by c o n v e n t i o n a l mach in ing procedures che reb j making the process uneconomica l Chemica l m i l l i n g o f some o f the s u p e r a l l o y and o x i d a t i o n r e s i s t a n t a l l o y s has been demons t ra ted as f e a s i b l e Chemical m i l l i n g o f these m a t e r i a l s r e q i i r e s c l o s e r c o n t r o l o f c h e m i c a l s i n b a t h as w e l l as b a t h t empe ra tu r e Chemical m i l l i n g r a t e s are s lower and s u r f a c e f i n i s h e s are no t as good as have been achieved w i t h aluminum CRITICAL PROBLEMS 1 No m a t e r i a l development i s r e q u i r e d b e f o r e process development 2 Chemical m i l l i n g i s economica l o n l y up t o 3/8 i n c h i n dep th The s u r f a c e f i n i s h a f t e r c h e m i c a l m i l l i n g i s u s u a l l y no b e t t e r than the o r i g i n a l f i n i s h 3 The normal r a t e o f m e t a l removal 0 001 i n c h / m i n o f s u r f a c e shou ld be doubled ALTERNATE PROCESSES CONVENTIONAL MACHINING NUMERICAL CONTROL MACHINING Code 01 00 01 00
194 CHART PROPOSED DEVELOPMENT PROGRAM OBJECTIVE BACKGROUND APPROACH The o b j e c t i v e s o f the proposed development program are 1 To e s t a b l i s h m e t a l r emova l r a t e s g r e a t e r t h a n 0 002 i n c h e s / m i n u t e 2 To c r e a t e no adverse m e t a l l u r g i c a l e f f e c t s w i t h i n the m a t e r i a l or on the s u r f a c e 3 To produce p a r t s t o t o l e r a n c e s w i t h i n + 0 005 inches M e c h a n i c a l m a c h i n i n g methods are capable o f mach in ing m a t e r i a l s down to about 0 070 gauge w i t h o u t t e a r i n g or e x c e s s i v e d i s t o r t i o n Chemical m i l l i n g and e l e c t r i c a l d i s c h a r g e m a c h i n i n g are used t o f u r t h e r reduce t h i c k n e s s The t o l e r a n c e s ach ieved by c h e m i c a l m i l l i n g are n o r m a l l y no b e t t e r t han those o f the s t a r t i n g m a t e r i a l Pas te c h e m i c a l m i l l i n g compounds have been deve loped f o r l o c a l a p p l i c a t i o n o f the p rocess t o an area or spo t on a p a r t Pas te compounds are however a p p r e c i a b l y s lower I n r e a c t i o n r a t e s than l i q u i d c h e m i c a l m i l l i n g s o l u t i o n s P o t e n t i a l methods f o r i n c r e a s i n g the m e t a l removal r a t e s d u r i n g l i q u i d b a t h c h e m i c a l m i l l i n g are by c h e m i c a l a d d i t i o n s by a g i t a t i o n o r a e r a t i o n o f s o l u t i o n by u l t r a s o n i c v i b r a t i o n o f the p a r t d u r i n g c h e m i c a l m i l l i n g and by t h e r m a l and e l e c t r i c a l p o t e n t i a l changes A l l o f these methods have been e v a l u a t e d by c h e m i c a l m i l l e r s f o r many aerospace m a t e r i a l s S u r f a c e f i n i s h ach ieved n o r m a l l y d i c t a t e s the l i m i t s o f the methods s e l e c t e d f o r i n c r e a s i n g m e t a l r emova l r a t e s The f o l l o w i n g i s a suggested approach f o r a c h i e v i n g the d e s i r e d o b j e c t i v e s f o r s c u l p t u r i n g t h i c k p l a t e s o f s u p e r a l l o y s r e f r a c t o r y a l l o y s o x i d a t i o n r e s i s t a n t a l l o y s and be t a t i t a n i u m by c h e m i c a l m i l l i n g 1 E v a l u a t e e t c h a n t s f o r each o f the s e l e c t e d m a t e r i a l s and o p t i m i z e s o l u t i o n s 2 E v a l u a t e methods f o r i n c r e a s i n g m e t a l removal r a t e s as f o l l o w s a M e c h a n i c a l a g i t a t i o n o f ba th E t c h n g r a t e vs f l u i d f l o w r a t e shou ld be d e t e r m i n e d and o p t i m i z e d b U l t r a s o n i c v i b r a t i o n o f p a r t i n ba th c E l e c t r i c a l p o t e n t i a l a p p l i e d t o p a r t d H e a t i n g o f b a t h e Combina t ions o f the above 3 E v a l u a t e c a p a b i l i t y o f developed improved methods f o r c h e m i c a l m i l l i n g o f pocke t s i n t h i c k p l a t e s e c t i o n s o f the s e l e c t e d m a t e r i a l 4 E v a l u a t e chem m i l l e d m a t e r i a l s t o d e t e r m i n e the presence o f any adverse m e t a l l u r g i c a l e f f e c t 3 Compi le recommended p rocedures f o r the v a r i o u s m a t e r i a l s
195 PRIORITY RATING WORKSHEET CHART P R O f i R A M F A C T O t t S P R 0 6 R A M PROBABIL ITY OF S U C C E S S a LOW ⢠MODERATE C R I T I C A L P R O B L E M S TO B E SOLVED Q F^Vl/ttOT TOO DIFFICULT JC 9 0 M E / D I F F I C U L T ⢠M A N Y / VERY DIFF ICULT G R O W T H P O T E N T I A L % LITTLE OR U N D E F I N A B L E a uco&Hn.t'^te poreMTiAL OTHER TWAN AIR FORCE NONE SOME MAMY FOR AIR FORCe F U N D I N G P R O C E S S APPLICATIONS ⢠Z 5 8 3 8 o 4- o 4 NECESSITY ⢠L O W Hiex iNMSTBV/in-Htft sovr I F F I T * X MOOtltATF - SOME EFFdtr OTHtR 'SoUCtJCS 0 n eMLiJsiVE AiK FoAct FUMVMa L I K E L Y | ^ NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH P B O B A 8 l l . i r Y FAIB. P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T l O A L I T Y V / E R Y H K T H H I « H FAIR L o w P R E d U E N C Y OF REQUIREMENT IM S Y S T E M MORE THAM 3 CeMPeHeUTS 2 3 C e M P o U E n r s S l N f l L E C e M P e N E N T DESIGN A L T E R N A T E S No ALTeeNATe R » E S E E N ONE ALTERNATE S E V B d A L A L T E R N A T E * M A T E R I A L S IMPLICATION New MA e c i n u Pt-v tjottituT ee<a o MATtClflL IMPOOVtMtWT E E S D NO PKoisLeM Foees 'eek i 12 8 4 i^ 9 b 3 3 2 I 6 3 6 4 o CALCULATE I PRIORITY S T E P S T E P S T E P 3 RAW s c o a e s FOR EACH R£F£REMm) CoMPfNtMT IN TABLtS AT tND OF PANEl WITH I JAW TOTHLS ENTEREV? M â¢StiMiuAeV AT g l S U T S V S T C I ^ S CIRCLE HIGHEST A A R P RAW S C O R E n = IN fACH CITHER S Y S T E M C l R C L C NEXT HI<SU£ST IF WITHIN 4 P O I N T S O F T O P S C O R E n NUMBER OF SysTEIUS Hl^H ^ LOW ^ S C O R E C I R C L E F R E Q U E N C Y DISTRIBUTION F A C T O R 2. f B E L O W i I 3 OK MOCLE NUMaeR OF S Y S T E M S L o w 0 t 2 R .MOEC 1 0 1 z t 4 1 1 1 3 1 *f 1 z 1 <f AARP RANM SCORES 2 3 n c ⢠⢠I I S H I o n ⢠⢠⢠⢠⢠TOTAL PRIORITY
196 TITLE GRINDING LARGE BERYLLIUM COMPONENTS CHART NO 361 PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT P r o d u c t i o n o f a b e r y l l i u m d i s c shaped r e f l e c t i n g m i r r o r 50 inches t o 100 inches i n d i ame te r o p t i c a l l y smooth on the concave s u r f a c e t o 1/20 o f a wave l e n g t h o f v i s i b l e and near v i s i b l e l i g h t The o p p o s i t e f ace would have a w a f f l e p a t t e r n t o save w e i g h t w i t h maximum r i g i d i t y The m i r r o r w i l l have a h o l e t h r o u g h i t s c e n t e r h o l e d i ame te r a p p r o x i m a t e l y 0 2 d i s c d i ame te r AARP REFERENCES B Chorts 177a, 178 P*FVP<; Chnrt. APPLICABLE PROCESS Code GRINDING FOLLOWED BY LAPPING AND ETCHING 5 02 01 /5 07 01 STATE OF THE ART ASSESSMENT No o b j e c t s o f t h i s c o n f i g u r a t i o n as l a r g e as those ment ioned have been produced f r o m b e r y l l i u m The M e r c u r y heat s h i e l d (72 D x 1/2 ) was o f somewhat s i m i l a r volume Research i s i n p r o g r e s s on methods f o r p r o d u c i n g l a r g e b l anks w i t h r i b b e d backs and low r e s i d u a l s t r e s s e s f r o m minimum amounts o f b e r y l l i u m Problems are a n t i c i p a t e d i n p r o c u r i n g base m e t a l f o rms w h i c h w i l l m i n i m i z e raw m a t e r i a l r e q u i r e m e n t s and i n m a c h i n i n g the components t o the d e s i r e d t o l e r a n c e s on f l a t n e s s and c u r v a t u r e and i n a v o i d i n g s u r f a c e damage M a c h i n i n g o p e r a t i o n s on b e r y l l i u m u s u a l l y cause s u r f a c e damage such as t w i n n i n g m i c r o c r a c k s and r e s i d u a l s t r e s s e s R e s i d u a l s t r e s s e s f r o m m a c h i n i n g may be superimposed on those r e m a i n i n g f r o m p r i o r p r o c e s s i n g The s u r f a c e damage can be e l i m i n a t e d by a n n e a l i n g and c h e m i c a l e t c h i n g the componenc A f t e c a r e f u l l y conducted g r i n d i n g o p e r a t i o n s r emoving about 0 002 inches f r o m each s u r f a c e shou ld be adequate Baths s u i t a b l e f o r the pu ipose and f o r d e v e l o p i n g r e f l e c t i v e s u r f a c e s are known I t i s b e l i e v e d t h a t t h i s m a n u f a c t u r i n g r e q u i r e m e n t c o u l d be met by g r i n d i n g t o shape l a p p i n g t o meet d i m e n s i o n a l r e q u i r e m e n t s and t h e n e t c h i n g t o remove damaged s u r f a c e l a y e r s Then the component c o u l d be immers ion p l a t e d w i t h n i c k e l or the N i 7P a l l o y p o l i s h e d and g i v e n a t h i n vacuum d e p o s i t e d c o a t i n g o f a luminum t o p r o v i d e t a r n i s h r e s i s t a n c e A l t h o u g h i n f o r m a t i o n i s l i m i t e d b e r y l l i u m m i r r o r s as l a r g e as 24 inches i n d i a m e t e r h i v e been produced S u c c e s s f u l m a c h i n i n g o f l a r g e components depends o n l y on n a t u r a l advances i n s t a t e o f the a r t and no m a n u f a c t u r i n g development program t o e s t a b l i s h the c a p a b i l i t y i s needed ALTERNATE PROCESSES ELECTROLYTIC GRINDING ( f o l l o w e d by l a p p i n g and e t c h i n g ) Code 3 02 02 /5 07 01
197 TITLE NUMERICALLY CONTROLLED MACHINING OF SCULPTURED SECTIONS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT The s c u l p t u r i n g or m a c h i n i n g o f complex t h r e e d i m e n s i o n a l shapes ou t o f f l a t and cu rved p l a t e segments t o be f a b r i c a t e d i n t o c o n i c a l semi monocoque s h e l l s up t o IS f e e t m d i ame te r and 3 inches t h i c k M a t e r i a l s Beta T i t a n i u m AARP REFERENCES E Chorfs 1 M _ B Char ts . 93 P«FVPS Char ts . APPLICABLE PROCESS NUMERICALLY CONTROLLED MILLING Code 5 01 02 STATE O F THE ART ASSESSMENT The p r i n c i p a l i nadequac ies are p h y s i c a l s i z e i n c o m b i n a t i o n w i t h r i g i d i t y and power c a p a c i t y Machines o f adequate s i z e a l r e a d y e x i s t f o r easy to machine m a t e r i a l s l i k e aluminum and I t seems h i g h l y p r o b a b l e t h a t normal SOA development w i l l cope w i t h the problems o f s i z e c o n t r o l D i s t o r t i o n and m e t a l l u r g i c a l damage c o u l d be s o l v e d by some c o m b i n a t i o n o f n u m e r i c a l l y c o n t r o l l e d m i l l i n g w i t h EDM and chemica l m i l l i n g P r o d u c t i o n w i l l be slow and c o s t l y bu t l a r g e q u a n t i t i e s a re no t i n d i c a t e d Problems i n mee t ing the m a n u f a c t u r i n g r e q u i r e m e n t s migh t be expec ted i n c o n t r o l l i n g d imens ions o f + 0 001 i n c h i n a c h i e v i n g smooth f i n i s h e s f r e e o f m e t a l l u r g i c a l damage or l a r g e 5 a x i s n u m e r i c a l l y c o n t r o l l e d m i l l i n g machines are no t a v a i l a b l e when needed i f The s t a t e o f the a r t assures t h a t the necessary 5 a x i s n u m e r i c a l l y c o n t r o l l e d m i l l i n g machine w i l l be p r o d u c i b l e and perhaps even i n e x i s t e n c e when the need a r i s e s W e l l over 100 have been p l a c e d on o r d e r by aerospace i n d u s t r y Requirement i s f o r over 500 No m a n u f a c t u r i n g development program i s recommended CRITICAL PROBLEMS NONE ALTERNATE PROCESSES ELECTRODISCHARGE MACHINING CHEMICAL MILLING Code 5 04 01 5 03 01
-1.96- TITLE ELECTROCHEMICAL TRIMMING OF LARGE SHEET METAL PARTS CHART PRIORITY 303 RELATED CAMR CHARTS aftT^ 70 I MANUFACTURING REQUIREMENT Tr imming p r i o r t o w e l d i n g o f segments o f t o r o i d a l s h e l l s made f r o m s t a i n l e s s s t e e l sheet The segments must match a d j a c e n t s e c t i o n s t o p r o v i d e a 0 003 i n c h gap f o r b u t t w e l d i n g Close t o l e r a n c e s on the gap are e s p e c i a l l y i m p o r t a n t f o r e l e c t r o n beam b u t t w e l d i n g The c i r c u l a r c r o s s s e c t i o n i s 20 f e e t the segments are assembled t o f o r m t o r u s d i a m e t e r s up t o 80 f e e t AARP REFERENCES E Charti l f i2_ B Charts 95b P&FVPS Char ts . APPLICABLE PROCESS ELECTROCHEMICAL MACHINING Code 5 03 02 STATE OF THE ART ASSESSMENT E l e c t r o c h e m i c a l and e l e c t r o d i s c h a r g e a re capable o f t r i m m i n g o r p r e p a r i n g edges a c c u r a t e l y ] w i t h o u t b u r r s Since t h e y e x e r t r e l a t i v e l y s m a l l f o r c e s the e l e c t r i c a l types o f m e t a l r emova l processes o f f e r advantages when p o r t a b l e u n i t s must be c o n s t r u c t e d Fu r the rmore no t o o l wear occurs i n t r u e e l e c t r o c h e m i c a l mach in ing and wear i s n e g l i g i b l e i n the m o d i f i e d process u s u a l l y te rmed e l e c t r o l y t i c g r i n d i n g No ECM or EDM equipment i s a v a i l a b l e i n the s i z e s needed t o handle p a r t s as l a r g e as those d e s c r i b e d i n the m a n u f a c t u r i n g r equ i r emen t However r o t a t i n g t a b l e s l a r g e enough t o h o l d the t o r o i d a l segments are b e l i e v e d t o be a v a i l a b l e La rge r ones can be b u i l t w i t h o u t much d i f f i c u l t y Skate t e chn iques u s i n g p o r t a b l e t r ack-mounted e l e c t r o c h e m i c a l or e l e c t r o d i s c h a r g e m a c h i n i n g t o o l s a l s o p r o v i d e a s t r a i g h t f o r w a r d approach f o r t r i m m i n g l a r g e segments o f s h e l l s Problems i n f i x t u r l n g and i n measurement and c o n t r o l systems are expec ted t o be more t oublesome than those concerned w i t h the r e s t o f the m a t e r i a l removal system I t may be p r a c t i c a l t o s u p p o r t the s e c t i o n s by i n f l a t i o n t echn iques M a c h i n i n g the two m a t c h i n g edges s i m u l t a n e o u s l y w i t h a p l u n g i n g e l e c t r o d e would In su re c l o s e t o l e r a n c e s M a c h i n i n g may have t o be pe r fo rmed i m m e d i a t e l y b e f o r e assembly u s i n g the same f i x t u r e s As an a l t e r n a t i v e t o the ska te t e c h n i q u e the t o r o i d a l s e c t i o n s c o u l d be h e l d i n f i x t u r e s on t a b l e s w h i c h would r o t a t e them w i t h r e s p e c t t o a r o t a t i n g e l e c t r o c h e m i c a l c u t t e r Wire d i s k or p lunge type e l e c t r o d e s may be a p p l i c a b l e t o b o t h systems f o r p r o v i d i n g r e l a t i v e m o t i o n between t h e t o o l and w o r k p i e c e Problems i n p r o v i d i n g p o r t a b l e equipment f o r p u l p i n g c o n t a i n i n g and c o l l e c t i n g the e l e c t r o l y t e (EI»1) or d i e l e c t r i c f l u i d (EDM) are expec ted t o be w i t h i n the s t a t e o f the a r t No development program I s proposed The m a n u f a c t u r i n g r e q u i r e m e n t s can be met by e x t e n d i n g the t o o l i n g concepts and a r t developed i n p r o d u c i n g s m a l l e r s h e l l s when end i t e m procurement i s d e s i r a b l e ALTERNATE PROCESSES ELECTRODISCHARGE MACHINING MILLING Code 5 04 01 5 01 02 \
199 TITLE CONTOURING COOLED RAMJET DIFFUSER LEADING EDGE CHART NO 3 0 5 PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT A r a m j e t d i f f u s e r i s t o be a r t i f i c i a l l y c o o l e d thus r e q u i r i n g t a n t a l u m or t u n g s t e n base a l l o y t u b i n g f o r f l o w o f the c o o l a n t The tube bundles i n the f o r m o f 4 f o o t d iamete r by 10 f o o t l o n g h o l l o w c y l i n d e r s must t e r m i n a t e a t the f r o n t i n an a e r o d y n a m i c a l l y sharp l e a d i n g k n i f e edge The l e a d i n g edge must be machined or con toured a c c u r a t e l y t o a t o l e r a n c e o f 0 005 i n c h on the r a d i u s AARP REFERENCES E Cha ti B Cho ts P&FVPS C h a r t s . M a t e r i a l Removal No 4 APPLICABLE PROCESS ELECTROCHEMICAL MACHINING (ECM) Code 5 03 02 STATE OF THE ART ASSESSMENT The d e s i g n o f t h i s component i s no t y e t developed wh ich leaves some l a t i t u d e o f cho i ce as t o p r o c e s s i n g T h i s i n v o l v e s two d e s i g n approaches (a ) S t r a i g h t t u b i n g t a s t ened to a separa te header (b ) Tub ing bent and formed 180° and assembled i n t o the f i n a l c o n f i g u r a t i o n Approach (a) r e q u i r e s e l e c t r o n beam w e l d i n g w i t h the f i n i s h c o n t o u r i n g be ing accompl i shed by a v a i l a b l e e l e c t r o c h e m i c a l or e l e c t r o d i s c h a r g e equipment Approach (b) p r e s e n t s a development p rob lem i n tube f o r m i n g but f i n i s h c o n t o u r i n g can be accompl ished by e i t h e r e l e c t r o c h e m i c a l or e l e c t r o d i s c h a r g e m a c h i n i n g No m a n u f a c t u r i n g development program i s recommended There would be no d imens ions i n s p e c t i o n p rob lem w i t h d e s i g n approach (a ) bu t t h e r e c o u l d be w i t h approach ( b ) (See the a t t a c h e d I n s p e c t i o n Supplement ) Bo th e l e c t r o c h e m i c a l and e l e c t r o d i s c h a r g e m a c h i n i n g are capable o f m a i n t a i n i n g the r e q u i r e d aimens o n a l accuracy E l e c t o d i s c h a r g e mach in ing c o u l d c r e a t e minor problems o f m e t a l l u r g i c a l damage i n v e r y t h i n w a l l e d s t r u c t u r e s and e l e c t r o c h e m i c a l m a c h i n i n g c o u l d c r e a t e f i n i s h problems w i t h i n f i l t r a t e d powder compacts Normal s t a t e o f the a r t development shou ld cope w i t h these problems by the t ime the need a r i s e s Other aspec ts w h i c h r e q u i r e c l o s e c o n t r o l a re (1 ) M a i n t a i n i n g t empera tu re o f the l e a d i n g edge below c r i t i c a l maximum l e v e l s (2 ) M a i n t a i n i n g d i m e n s i o n a l accuracy t o s u s t a i n aerodynamic s t a b i l i t y ( 3 ) M a i n t a i n i n g u n i f o r m l y low heat t r a n s f e r p a t h w h i l e p r o v i d i n g s u f f i c i e n t s t r e n g t h (4 ) M a i n t a i n i n g u n i f o r m t h i c k n e s s o f the c o o l a n t passage w a l l s f r o m 0 020 inches t o 0 005 inches No m a n u f a c t u r i n g development program i s r e q u i r e d t o e s t a b l i s h t h i s c a p a b i l i t y Con t inued on nex t page ALTERNATE PROCESSES ELECTRODISCHARGE MACHINING (EDM) Code 5 04 01
200 OBJECTIVE C H A R T , ^ NO 3(P, INSPECTION TECHNIQUES SUPPLEMENTAL RECOMMENDATIONS I n s p e c t c o o l e d l e a d i n g edge o£ d l f f u s e r assembly f o r supe r son ic r a m j e t or s c r a m j e t Lead ing edge i s t o be a e r o d y n a m i c a l l y sharp t o m i n i m i z e h e a t i n g and I n t e r n a l l y c o o l e d t o m a i n t a i n s e r v i c e t empera tu re P r ime a t t r i b u t e s are sharpnese o f l e a d i n g edge and s p e c i f i e d tube w a l l t h i c k n e s s BACKGROUND Contour and sharpness o f the l e a d i n g edge can be e v a l u a t e d w i t h e x i s t i n g o p t i c a l i n s p e c t i o n equipment and c a l i b r a t e d u l t h r e p l i c a t i o n t e chn iques W a l l t h i c k n e s s i n the range f r o m 0 005 t o 0 020 Inches can be measured w i t h eddy c u r r e n t and u l t r a s o n i c resonance t echn iques Some development may be needed t o produce s m a l l c o n t o u r e d probes t o account f o r c u r v a t u r e APPROACH 1 S tandard c o r r e l a t i o n and c a l i b r a t i o n s t u d i e s 2 Probe development i f tube d iamete r s are s m a l l or bends are sharp
201 TITLE METAL REMOVAL FROM SUBSTRUCTURE BY E L E C T R O C H E M I C A L M I L L I N G CHART PRIORITY MANUFACTURING REQUIREMENT M e t a l r emova l f r o m s u b s t r u c t u r e s such as bulkheads f rames s t i f f e n e r s t r u s s members and f i t t i n g s on s u p e r a l l o y s r e f r a c t o r y a l l o y s and o x i d a t i o n r e s i s t a n t a l l o y s The m a t e r i a l fo rms can be p l a t e bar f o r g i n g s e x t r u s i o n s and c a s t i n g s Members may be as l a r g e as 6 f o o t l ong AARP REFERENCES . r u â . . 55 86 R r h â ic 31a b c d 42a b c PSFVPS Charts - â â APPLICABLE PROCESS Code ELECTROCHEMICAL MILLING 5 03 02 STATE OF THE ART ASSESSMENT S u b s t r u c t u r e components are now b e i n g made p r i m a r i l y o f a luminum and h i g h s t r e n g t h s t e e l s The ma jo r o p e r a t i o n s are c o n t o u r m i l l i n g s c u l p t u r i n g and p o c k e t i n g and are be ing p e r f o r m e d p r i n c i p a l l y by e i t h e r t r a c e r or n u m e r i c a l c o n t r o l m i l l i n g machines S i m i l a r m i l l i n g t e c h n i q u e s on s u p e r a l l o y s r e f r a c t o r y a l l o y s and o x i d a t i o n r e s i s t a n t a l l o y s are p o s s i b l e o n l y a t v e r y s low r a t e s by c o n v e n t i o n a l m i l l i n g p rocedures Some o f the r e f r a c t o r y m a t e r i a l s such as t u n g s t e n and c a s t n i c k e l base a l l o y s have such poor m i l l i n g c h a r a c t e r i s t i c s t h a t i t i s q u e s t i o n a b l e whether m i l l i n g c o u l d be used t o produce p a r t s E l e c t r o c h e m i c a l m a c h i n i n g has been p e r f o r m e d as a c a v i t y s i n k i n g o p e r a t i o n p r i m a r i l y on s m a l l components where s m a l l p o c k e t i n g o p e r a t i o n s have been r e q u i r e d P o c k e t i n g and c o n t o u r i n g o f l a r g e components would r e q u i r e ECM machines o f much l a r g e r s i z e and much h i g h e r f o r c e and amperage c a p a c i t y than t h a t w h i c h now e x i s t s The f o l l o w i n g ECM machines and process f e a t u r e s are r e q u i r e d bu t i t i s b e l i e v e d t h a t they may w e l l occur w i t h i n the s t a t e o f the a r t development 1 ECM Machine Fea tures a Large machines are g o i n g to have Lo be b u i l t t o accommodate the 6 f o o t or l onge r s u b s t r u c t u r e p a r t s b Machines w i l l have t o be e x t r e m e l y r i g i d to w i t h s t a n d the l a r g e f o r c e s accompanying the l a r g e c r o s s s e c t i o n a l a reas t o be s c u l p t u r e d f r o m Che s u b s t r u c t u r e component For example i n m a c h i n i n g a 10 i n c h x 20 i n c h or 200 sq i n c h area pocke t u s i n g the c o n v e n t i o n a l e l e c t r o l y t i c p re s su res o f 400 t o 500 p s i the f o r c e on the component would be 80 000 t o 100 000 lbs c La rge r c a p a c i t y power s u p p l i e s w i l l have t o be deve loped f o r l a r g e pocke t s For example the 200 sq i n c h area pocket would r e q u i r e a 60 000 t o 200 000 amp power s u p p l y ECM Process Fea tu re s a P r i n c i p l e s o f e l e c t r o d e d e s i g n w i l l have Co be deve loped t o enable more Con t inued on n e x t page ALTERNATE PROCESSES ELECTRICAL DISCHARGE MILLING CHEMICAL MILLING CONVENTIONAL MILLING Code 5 04 01 5 03 01 5 01 02
202 NO 302 STATE OF THE ART ASSESSMENT, contimipri engineers to use ECM At present only a few companies i n the U S have adequate electrode design and f l u i d flow experience to f e e l confident i n applying ECM I t might be advisable to consider s e t t i n g up some c e n t r a l design sources for ECM electrode and tooling b The control of surface f i n i s h and dimensional tolerances i n ECM i s li k e w i s e determined by proper f l u i d flow of the e l e c t r o l y t e between the electrode the work and the f i x t u r e I t i s necessary to develop p r i n c i p l e s of e l e c t r o l y t e f l u i d flow i n order to s u c c e s s f u l l y apply ECM Metal removal by generation rather than by forming techniques should be considered as an ECM process This might make i t possible to generate large pockets and would minimize the problems i n handling large areas c Continued Improvement of the ECM process i s required^ to Increase by a factor of 2,the metal removal r a t e s d I n v e s t i g a t i o n should be made on the r e l a t i o n of the e f f e c t of the ECM process on the surface i n t e g r i t y of the machined surface including r e s i d u a l s t r e s s p l a s t i c deformation m e t a l l u r g i c a l transformations Furthermore the r e s u l t of the surface changes on component d i s t o r t i o n as w e l l as p h y s i c a l and mechanical properties of mat e r i a l s should be investigated No manufacturing development program i s considered necessary to achieve the desired manufacturing c a p a b i l i t y
203 TITLE MACHINING OF 0 RING GROOVES CHART PRIORITY R E L A T E D C A M R C H A R T S MANUFACTURING REQUIREMENT Large 0 ring grooves up to 3 foot i n diameter for s e a l i n g docking t r a n s f e r hatches w i l l have to be machined e s p e c i a l l y f l a t and accurate and w i l l a l s o have to have a surface f i n i s h not exceeding 8 microinches The allowable cabin a i r leakage rate i s one pound per day Multiple latches are required i n a docking energy absorber to provide uniform s e a l compression between mating surfaces of the spacecraft and a space platform AARP REFERENCES F r h n r t . 316 317 B C h a r t s 152 P A F V P S r h n r t . APPLICABLE PROCESS C o d e TURNING 5 01 01 STATE OF THE ART ASSESSMENT The machining of 0 ring grooves can be done by conventional turning i f a c i r c u l a r 0 ring groove i s required Generally t h i s operation i s performed as a plunging operation on some type of a lathe I n order to achieve high surface f i n i s h i t might be d e s i r a b l e to generate the groove rather than form i t by plunging Obtaining high dimensional accuracy and high degree of f l a t n e s s and surface f i n i s h may require the consideration of grinding or mechanized p o l i s h i n g rather than turning as the f i n i s h i n g operation for the grooves I f the 0 r i n g s e a l i s non c i r c u l a r then the groove would have to be machined by end m i l l i n g Here again the groove would have to be fi n i s h e d by grinding or pol i s h i n g i n order to obtain s a t i s f a c t o r y surface f i n i s h No development program i s considered necessary CRITICAL PROBLEMS NONE ALTERNATE PROCESSES MILLING GRINDING C o d e 5 01 02 5 02 00
204 TITLE MACHINING BERYLLIUM AND MAGNESIUM COMPONENTS CHART PRIORITY R E L A T E D C A M R C H A R T S MANUFACTURING REQUIREMENT Metal removal on shrouds n a c e l l e s and docking energy absorber l a t c h e s i s required on beryllium and magnesium The m a t e r i a l form can be sheet p l a t e or bar The b e r y l l i u m can be i n the form of the truncated contour s h e l l s up to 50 inches diameter 0 020 inch to 0 250 inch t h i c k and 100 inches long (t o l e r a n c e s + 0 010 inch) AARP REFERENCES E C h a r t s - B C h a r t s . 136 67. 70. 72 P 4 F V P S C h a r t s . APPLICABLE PROCESS ALL MACHINING PROCESSES C o d e 5 00 00 STATE OF THE ART ASSESSMENT Beryllium at the present time can be f a b r i c a t e d by most of the conventional as w e l l as nonconventional processes including turning m i l l i n g d r i l l i n g tapping and grinding as w e l l as ECM and EDM However the production rate tends to be slow for two reasons 1 Machining beryllium i s a health hazard and s p e c i a l f a c i l i t i e s procedures and precautions are necessary to insure s a f t e y for the workman 2 In machining of beryllium there i s a tendency for twinning and c r a c k i n g to occur i n the f i n a l surface The depth of the surface damage i s a function of the depth of cut so that p r o g r e s s i v e l y l i g h t e r depths of cut are required to l i m i t the depth of surface damage Many of the beryllium parts have to have e l e c t r i c a l machining or e l e c t r o l y t i c etching as a f i n a l operation to remove the e f f e c t s of previous machining The machining of large magnesium components req u i r e s c a r e f u l c o ntrol of ambient tempera ture to insure maintenance of s i z e and accuracy No development program i s considered necessary CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE C o d e
205 TITLE MACHINING COOLANT PASSAGES IN TURBINE BLADES AND VANES CHART PRIORITY R E U T E D C A M R C H A R T S UO MANUFACTURING REQUIREMENT To provide coolant passages In r e f r a c t o r y a l l o y and composite ceramic turbine blades and vanes Passages would be up to 6 Inches long 0 030 to 0 050 Inch diameter to a tolerance of + 0 002 Inch with w a l l thickness down to 0 030 Inch + 0 002 Inch Tolerances on a i r f o i l s urfaces of f i n i s h e d blades must be maintained at + 0 005 inch 0 000 Inch AARP REFERENCES B Chn ts PSFVPS Chnrts Material Removal No 2 APPLICABLE PROCESS Code ELECTROCHEMICAL DRILLING (for r e f r a c t o r y a l l o y s ) 5 03 02 DRILLING (for composite ceramics) 5 07 02 STATE OF THE ART ASSESSMENT Refractory a l l o y s Electrochemical m i l l i n g (ECM) has been In use for deep hole d r i l l i n g and can be expected to develop s a t i s f a c t o r i l y for the hole s i z e s s p e c i f i e d Passages of 0 020 to 0 030 Inch diameter are p o s s i b l e today D i f f i c u l t i e s can be expected I f smaller holes become necessary The tolerance on w a l l thickness between the hole and the a i r f o i l surface 0 002 inch would be s t r e t c h i n g the current c a p a b i l i t y Further development i n control of passage development and In reading w a l l thickness i s needed but should r e s u l t from normal s t a t e of the a r t development ECM has been demonstrated for most metals Including the high n i c k e l a l l o y s and r e f r a c t o r y a l l o y s p a r t i c u l a r l y tungsten Columbium and molybdenum are considered f e a s i b l e although s p e c i a l e l e c t r o l y t e s may be required No manufacturing development program would be necessary to provide the indicated c a p a b i l i t y for r e f r a c t o r y a l l o y s Ceramic composites L i t t l e has been done on small hole d r i l l i n g i n ceramic composites At t h i s time no requirement to d r i l l deep holes i n ceramic composites would be anti c i p a t e d I n some cases holeij would be p ovlded by techniques othe than machining I f the mate i a l s can be ca t the holes may be c a s t In place A program for hole development should be an I n t e g r a l part of composite ma t e r i a l process development for use as blades and vanes When mat e r i a l removal processes are necessary u l t r a s o n i c techniques may be a p p l i c a b l e CAMR Chart 310 o u t l i n e s a development program for t h i s process Electrochemical machining would work for m e t a l l i c portions of a composite as indicated i n the d i s c u s s i o n for r e f r a c t o r y a l l o y s The non-metallic portions of the composite would cause serious problems by i n t e r r u p t i n g the current Filamentary composites are extremely d i f f i c u l t to machine by conventional tools due to high hardness of filaments E l e c t r o d i s c h a r g e machining has been e f f e c t i v e l y used to machine metal matrix composites No separate development program for machining coolant passages i n turbine blades and vanes i s recommended ALTERNATE PROCESSES Refractory a l l o y s ELECTRODISCHARGE MACHINING (for shallower h o l e s ) Ceramic composites ULTRASONICS ABRASIVE BLAST GRINDING Code 5 OA 01 5 07 02 5 06 01 5 02 01
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS, AND AARP RATING FACTORS I CAMR CHART NUHQCR 3ot I 3â¬^3 30^ \ 3cC 30^ 301 BP B-177a. 178 Componenc 07 04 0 OPTICAL MIRROR AND ElEFLECTOR f o r C-3a c o l l e c c o r m i r r o r / o p t l e a l t e l e s c o p e and C-Sb r e f l e c t i n g m i r r o r s y s t e m REF B-93 Component 02 06 0 THRUST STRUCTURE f o r B - l b ( l ) s p a c e l a u n c h s y s t e m - e a r t h o r b i t l a u n c h and B - l b ( 2 ) s p a c e l a u n c h s y s t e m - l u n a r l a u n c h REF B-95b Component 02 04 0 PRESSURE V E S S E L f o r B - l b ( l ) and B - l b ( 2 ) s y s t e m s a s above EtEF B-83a and P r o p u l s i o n R e q u i r e m e n t M a t e r i a l Removal No 1 Component 16 01 0/02 0 5 0 SOLID ROCKET MOTOR CASE f o r B - l a ( l ) e a r t h l a u n c h s y s t e m - r e c o v e r a b l e b o o s t e r and B-laC2) e a r t h l a u n c h s > s L e m - s l n o l e s t a t e Co o r b i t r e c o v e r a b l e b o o s t e r , f o r A-4b(2) s t r a t e g i c m l s s i l e - s t o r a b l e ICBM, A - 4 b ( 3 ) s t r a t e g i c m l s a H e - a p a c e l a u n c h e d ICBM, and B-2a(3) n e a r s p a c e o p e r a t i o n s s p a c e c r a f t - l u n a r v e h i c l e REF P r o p u l s i o n R e q u i r e m e n t M a t e r i a l Removal No 4 Component 13 01 0 RAMJET DIFFUSER LEADING E K E fo r B - l o ( l ) e a r t h l a u n c h s y s c e m - l e c o v c r a b l e b o o s t e r R E F B - 6 1 d Cooiponcnt 01 03 O NOSE f o r A - * b ( 4 ) S t r a t e g i c m i s s i l e r e - e n t r y s y s t e m s REF B-145b Componenc 01 02 0 AERODYNAMIC L I F T & CONTROL STRUCTURE - F L E X I B L E WING f o r B-4a e a r t h l a n d i n g s y s t e m REF B-149b 150b Component 01 02 3 AERODYNAMIC L I F T & COWTROL STRUCTURE - FLEX DECELERATOR ond 01 02 04 FLEX ROTOR f o r B-4o e a r t h l e n d i n g syBCcma REF B -30a.b.c. 4 1 a , b . c Component 01 01 1 AERO- DYNAMIC L I F T h CONTROL STRUCTURE - R I G I D S K I N f o r A-3a h y p e r s o n i c c r u i s e h i g h a l t i t u d e and low a l t i t u d e v e h i c l e s and A-3b h y p e r s o n i c b o o s t g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e s R E F B-134b Componenc 01 01 1/01 01 2 AERODYNAMIC L I F T h. CONTROL STRUCTURE - R I G I D S K I N / R I C I D SUB- STRUCTURE f o r B-3b d r a g e n t r y v e h i c l e s REF B - l l l a , b Component 06 03 0/07 01 0 SOLAR COLLECTOR STRUCTURE/ANTENNA f o r B - 2 a ( l ) n e a r a p a c e o p e r a t i o n s - e a r t h s a t e l l i t e , B - 2 a ( 2 ) n e a r s p a c e o p e r a t i o n s - s p a c e s t a t i o n , and B - 2 a ( 3 ) n e a r s p a c e o p e r a t i o n s - l u n a r v e h i c l e REF B-133d,c Component 08 01 0 HEAT S H I E L D f o r B-3b drat, e n t r y v e h i c l e S Y S T E M PROBAeiLirt COMPONENT CRITICAUTV FREauCNCy OF snvcT IN SYSTEM DESIGN ALTERNA MATCRlmS IMPUCAnOH AARP RAW S C O R E S 11 e 4 l£ ^ 3 1-1 1-c 3 8 t 9 t> 31 8 9 t 9 0 3t / 2 9 / o 0 Z8 4 / 9 1 6 o 0 2o /Z / 9 o 0 31 Â¥ 9 1 9 o 0 23 fi.%oS,o, S.lp-(i) 8 %⢠3 _ 3r o 0 22 Â¥ 9 %⢠o 0 /e Jt.ojo. /2 9 1 c i> tz 0 2g e> 8 9 1 6 . / , i o / f i . e 9 2 c 9 £ 6 6 0 2 r 0 3o^_ 0 Si. ./<,<?/.«. Â¥ /Z .13.61.0. .Brl.CL.6] e _ / 3 .O.I.OSc, /2 _ 3 /Z c pi ax J ,B-</e^ / * a o t> £9 .^-yv. tz f 2 3 0 0 ZA / i /Z z 3 Z e> O/oJJ A.3.0, , e /Z / o i> Z3 .0.1 pi. 1^ /2 1 2 o i> /9 Olell ,8-36^ IZ 6 2 Z o 0 2Z fi6 <>S0 82eiOj /2 9 f 2 O 0 1*^ OCpS.o ,8 2a<i^ /z 9 / 2 o ii ZÂ¥ Oflpio .S2af3) 9 / 2. O O&eilo g3l> /z /Z 2. 3 o 0 29
EXPLANATION OF CAMR REPCRENCES TO SYSTEMS. COMPONENTS. AND AARP RATING FACTORS CAMR CHAUX NUMQCR, 3e>9 3/0 REP B - 3 1 a , b , c , d , 4 2 s b , c Component: 01 01 2 AERODYNAMIC L I F T & COrfTROL STRUCTURE - R I G I D SUBSTRUCTURE f o r A-3a h y p e r s o n i c c r u i s e hLgh or low a l t l c u d e v e h i c l e s and A-3b h y p e r s o n i c b o o s t g l i d e s t r a C e g i c o r t a c t i c a l v e h i c l e s REP B-151 Component 05 02 0 ENBRGY ABSORBER f o r B-4b s p a c e l a n d i n g v e h i c l e REP B-1S2 Component 09 02 0 S E A L f o r B-Ab s p a c e l a n d i n g v e h i c l e REP B-30e, i l e Component 01 01 1 AERODniAMIC L I F T & CONTROL STRUCTURE - R I G I D S K I N f o r A-3a h y p e r s o n i c c r u i s e h i g h a l t i t u d e o r low a l t i t u d e v e h i c l e and A-3b h y p e r s o n i c b o o s t g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e REP B-126a b Component 09 01 0 BEARING f o r B-3a l i f t r e - e n t r y v e h i c l e REP P r o p u l s i o n R e q u i r e m e n t M a t e r i a l Removal Ho 3 Components 10 03 0 TURBOJET VANES 11 03 0 TURBOROCKET TURBINE NOZZLES 11 08 0 TURBOROCKET BEARINGS, 12 03 0 TURBORAMJET TURBINE VANES, 12 OH 0 TURfiORAHJET BEARINGS. 12/12/0 TURBOBAKJtIT COIBUSTION CHAMBER L I N E R S 13 03 0 RAMJET COMBUSTION CHAHBER L I N E R S , l A 02 0 L I Q U I D ROCKET NOZZLE, K OA 0 L I Q U I D ROCKET S E A L 15 01 0 NUCLEAR ROCKET MOTOR NOZZLE. 15 02 0 NUCLEAR ROCKET MOTOR SE A L 16 0 3 0 S O L I D ROCKET N02Z1£, 16 0 5 0 S O L I D ROCKET HOT GAS VALVE, 18 02 0 GASEOUS POWER SYSTEM BEARINGS, 21 02 0 THERMOELECTRIC POWER SYSTEM ELEMENTS, 21 03 0 THERMIONIC POWER SYSTEM CATHODE, 22 01 0 CLOSED CYCLE TURBOELECTRIC POWER SYSTEM BEARINGS T h e above components a r e i n v o l v e d I n d e v i c e s w h i c h may f i n d u s e i n a m a j o r i t y o f f l i g h t v e h i c l e s R E F B - i l a , b , c Component 01 01 1 AERODYNAMIC L I F T & CONTROL STRUCTURE - R I G I D S K I H f o r A-3b h y p e r - s o n i c b o o s t g l i d e s t r a t e g i c o r t a c t i c a l v e h i c l e REP B-30a,b.c Component 01 01 2 AERODYNAMIC L I F T & CONTROL STRUCTURE - R I G I D SUBSTRUCTURE f o r A-3a h y p e r s o n i c c r u i s e h i g h a l t i t u d e o r low a l t i t u d e v e h i c l e REF B-93 Component 02 06 0 THRUST STRUCTURE f o r B - l b ( l ) s p a c e l a u n c h s y s t e m - e a r t h o r b i t l a u n c h and B - l b ( 2 ) s p a c e l a u n c h s y b t e m - l u n a r l a u n c h R E F B-32B,b Component 0 6 01 0 A I R I N L E T S b DtX^ING f o r A-3a h y p e r s o n i c c r u i s e v e h i c l e a s above REFERENCES - T h i s CAMR c h a r t p e r t a i n s t o a l l o t h e r M a t e r i a l Removal c h a r t s and i n c o r p o r a t e s t h e i r r e f e r e n c e s f o r p r i o r i t y c a l c u l a t i o n p u r p o s e s nolo 12 es-e It oe.0 ttolo y.o.l". SYSTEM OOMraNEHT CRITICAUrr FREQUCNCY OF lawt IN SYSTEÂ»Ì DESIGN ALTERNA i ItATERIAlS IMfUCAnox AARP RAW SCORES It. e 4 It <) fe-3 3 1 1 I t s £ JJ -0 T a r At S 6 6 3 c i> 23 Â¥ 9 3 0 iZ 9 / 3 0 2S C / 3 0 0 SZ /« / 6 e 0 33 Â¥ /a. / i 6 0 z<f 8 3 / 0 0 Zit 0 0 j)i te7>/ 0 en Aee«b 0 te 2>isi s*/p 0 jtj 0 So Off ^ CM ^ 0 >^ / > a 0 0 /tif TJm fiMir Ij 'fenOA/ 0 : 33). am, t> ⢠Cr, 0 0 e> 0 0 Â¥ n / 6 0 0 93 6 2 6 a 9 / 6 0 0 2g Â¥ 9 / 6 0 0 Zo e 9 2 6 0 i) 25- <> 0
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS, AND AARP RATING FACTORS CAMR CHMtr NUHBCR 3/3 REF B-67, 70. 72 Component 04 02 0 FAIEIHO (SHROUD, NACELIE) for A-4b(l) s t r a t e s U m i s s i l e - mobile i c m , A-4b(2) scrsteglc m i s s i l e - storable ICBM, A-«b(3) scrsteglc m i s s i l e - space launched ICBM, and A-4b(4} strategic re-entry system REP Propulsion Requirenent Material Removal No 2 Componenta 10 03 0 TURBOJET TURBIKB VANES and 10 05 0 TURBOJET TURBINE BLADES for A-2a auper- Gonlc high a l t i t u d e long range chemically fueled a i r c r a f t and A-2c auperaonlc V/STOL t a c t i c a l f i g h t e r Is ll o.fi'M Af.b.O} S Y S T C M C O M P O N E N T cRiricAurr OF mvit I N S V S T E I A DESIGN ALTERMA C3 M A T E R I I U S IHmCATIOII AARP RAW 3 C O R E : S I t e 4 11 t 6 i 3 -z-l T»-PAL 3 / c o i> // fit/otp, .A.<ll><ii 3 / o 0 22. $ 3 / 0 /e 3 / O i> ZZ Jo.ea.a , /z 1 ^ 6 0 33 J(>j,3.p. A-^f. /«- 9 a 6 0 31 a n 6 t <> J t f fe^oSo . / J i f . /t- 2 - C V 0 3i 1 . > . > 0 0 , . . . . 1 ⢠⢠⢠1 0 , . . 0 . . . i l l . . . . 0 0 0 0 0 0 0 c> 0 0 i> e> 0 (> i> i> 0 i) 0 0 0 i>
⢠2 0 9 - PANEL ON JOINING AND MECHANICAL FASTENING Members Li a i s o n Mr A H Petersen, Chairman Mr W J F a r r e l l Mr Richard K May Dr Arthur G Metcalfe Mr Terence F Imholz Mr Wayne Reinsch Mr Francis J Wallace Mr G a l l E Eichelman Mr Fred R M i l l e r Special Advisors Mr F K Lampson Marquardt Corporation Mr Mel Schwartz Martin Company Mr Robert L Sproat Standard Pressed Steel Company Mr W T Kaarlela General Djmamics/Fort Worth
â¢211- 2 4 JOINING A Summary of Problems and Recommendations The J o i n i n g Panel's study of the m a t e r i a l s of i n t e r e s t t o AARP and the many new m a t e r i a l s which have come i n t o being since AARP f i n i s h e d i t s t a s k , brought the conclusion t h a t the desired goals could best be obtained by analyzing the basic processes used, recommending s p e c i f i c improvements i n these and d e f i n i n g the development of other processes as a l t e r n a t e approaches The recommended programs propose t o delve i n t o the process v a r i a b l e s i n depth, and thus gain a b e t t e r understanding of fundamentals t o upgrade known processes and t o put new ones on a sound production f o o t i n g This has been the approach f o r a l l processes examined, 1 e , welding (both f u s i o n and r e s i s t a n c e ) , b r a z i n g , adhesive bonding and d i f f u s i o n bonding I t was s t r o n g l y f e l t by the Panel th a t the producers of new f a m i l i e s of aerospace a l l o y s must give more a t t e n t i o n t o the l i m i t a t i o n s of fu s i o n and brazing processes during the development cycle The search f o r new and Improved processes w i l l b r i n g decided b e n e f i t s , nevertheless, many of the problems AARP reported might have been resolved e a r l i e r , or not have occurred at a l l , had there been con- current m a t e r i a l and process development I n t r o d u c i n g new m a t e r i a l s during a program system development phase can be a primary cause of delays and schedule slippage Along these l i n e s , several Panel authors have suggested the "systems approach" i n t h e i r programs They propose t h a t t y p i c a l designs be developed f o r h o s t i l e environments using new mate r i a l s which q u a l i f y on paper These designs would then be produced through step-by-step development of production processes The ASSET program i s quoted as an example of t h i s method While t h i s technique has many advantages, i t i s sometimes extremely d i f f i c u l t and c o s t l y t o s t r u c t u r e programs so t h a t s o l u t i o n s t o selected problems can provide s p e c i f i c r u l e s t h a t designers may use i n other a p p l i c a t i o n s I d e n t i f i c a t i o n o f process l i m i t a t i o n s (and the e f f o r t s t o reduce these) must be continuous and c l o s e l y t i e d t o m a t e r i a l s development t o provide m u l t i p l e design approaches i n advance of the need I t can be concluded t h a t good Judgment must determine which path t o pursue The Panel was unanimous i n t h e i r f e e l i n g t h a t non- d e s t r u c t i v e i n s p e c t i o n techniques a p p l i e d t o an end-item are not the u l t i m a t e s o l u t i o n t o the problems of i d e n t i f y i n g weld, braze, and adhesive bond q u a l i t y Rather, a strong plea i s made i n many charts f o r accurate in-process c o n t r o l s which would monitor every sequential step, and where
-212- automated equipment I s used, would compensate and adjust f o r degrading v a r i a b l e s Fusion Welding Perhaps the most c r i t i c a l processes were those i n - v o l v i n g f u s i o n The Panel's study revealed problems i n two broad categories The f i r s t , and most d i f f i c u l t t o solve, i s t h a t of the m e t a l l u r g i c a l problems where loss o f parent metal s t r e n g t h i n the weld zone i s the end e f f e c t T y p i c a l of the reasons given f o r t h i s loss are o Grain growth o P o r o s i t y o PrecIp i t at ions o Pick-up of undesirable i n t e r s t i t i a l elements o D i s t o r t i o n and cracking due t o Induced s t r e s s Loss of toughness and f a t i g u e s t r e n g t h r e d u c t i o n can also occur The second category includes o Accurate f i t - u p of p a r t s o A c c e s s i b i l i t y o Surface contamination and d i f f i c u l t i e s i n maintai n i n g the r e q u i s i t e c l e a n l i n e s s o Lack of adequate process c o n t r o l s t o insure the r e l i a b i l i t y o f the end product o Nondestructive t e s t methods t h a t w i l l seek out and i d e n t i f y a l l possible types of d e f e c t s , which might c o n t r i b u t e t o premature f a i l u r e These problems are, of course, magnified by the types of m a t e r i a l s and combinations o f m a t e r i a l s described I n the AARP documents Reactive metals, d i s p e r s i o n strengthened a l l o y s , a l l o y s o f very high s t r e n g t h and r e f r a c t o r y a l l o y s w i t h very high m e l t i n g temperatures have compounded many of the problems c i t e d by AARP The use of s p e c i a l a l l o y e d f i l l e r wires and I n t e r - face a d d i t i o n s i s an important c o n s i d e r a t i o n i n welding systems Much more basic m e t a l l u r g i c a l work i n t h i s area i s needed and should be very rewarding This work and work on u l t r a s o n i c weld puddle s t i r r i n g , super-cooling techniques, and other advanced studies are referenced i n app l i c a b l e c h a r t s A b e t t e r c a p a b i l i t y f o r e v a l u a t i o n of weldments i s needed The e f f e c t of imperfections on low cy c l e f a t i g u e s t r e n g t h r e q u i r e s extensive e v a l u a t i o n , e s p e c i a l l y f o r small s i z e Imperfections below present i n s p e c t i o n l i m i t s There has been much work i n the f i e l d o f l i n e a r e l a s t i c f r a c t u r e mechanics, but s t r e s s i n t e n s i t y f a c t o r s and f r a c t u r e toughness evaluations have not prevented a l l service
-213- f a i l u r e s S tructures are not always inspectable t o the f l a w size l i m i t s i n d i c a t e d by analyses Improvement i s needed i n s p e c i f i c a t i o n d e f i n i t i o n s of r e j e c t a b l e l i m i t s of flaws Brazing Brazing process problems i n v o l v e c o m p a t i b i l i t y of the braze a l l o y w i t h the m a t e r i a l s t o be j o i n e d , i n terms of d i f f u s i o n , p r e c i p i t a t i o n and changes i n d u c t i l e - b r i t t l e t r a n s i t i o n temperatures f o r the r e f r a c t o r y a l l o y s Most brazing techniques used are time consuming, c o s t l y and l i m i t e d t o hardware of simple geometry The pressures and temperatures r e q u i r e d t o achieve j o i n t s of s u i t a b l e strengths Involve considerable c a p i t a l expense, which discourages widespread use The authors have emphasized the need t o pool e x i s t i n g knowledge on p r o p r i e t a r y braze a l l o y s and processes as a f i r s t step i n a r r i v i n g at more u n i v e r s a l and economic systems The c u r r e n t work on cladding and c o a t i n g of metals t o achieve o x i d a t i o n and c o r r o s i o n resistance might be a technique f o r i n c o r p o r a t i n g the braze a l l o y d i r e c t l y onto the base metal Perhaps s i m p l i f i c a t i o n s t o the present r a t h e r laborious and c o s t l y processes could r e s u l t w i t h Improvement i n r e l i a b i l i t y and p r o p e r t i e s Mechanical Fastening I n the f i e l d of mechanical f a s t e n i n g , the Panel had to consider both fasteners and the j o i n t s The shear and bearing values f o r m a t e r i a l s , edge distance from the fastener hole and the f i t of the fastener i n the hole are considerations o f Importance t o the designer Excessive r a d i a l stresses can be induced around the hole by fasteners d r i v e n too t i g h t l y Strength i s reduced I f fasteners are loose Hole preparation and fastener i n s t a l l a t i o n p r a c t i c e s are of great Importance as manufacturing operations, and f u r t h e r a t t e n t i o n t o them i s considered worthwhile For t h e h o s t i l e environments i d e n t i f i e d by AARP, where r e f r a c t o r y and h i g h l y r e a c t i v e a l l o y s are used i n s t r u c t u r e s , emphasis should be on the a l t e r n a t e design approaches r a t h e r than c r e a t i o n of a m u l t i t u d e of s p e c i a l i z e d fastener c o n f i g u r a t i o n s f o r l i m i t e d usage Most aerospace companies attempt t o r e s t r i c t the s e l e c t i o n of fasteners by designers, f o r purposes o f cost and i n v e n t o r y c o n t r o l I t I s I n the i n s t a l l a t i o n of fasteners t h a t high costs are created High s t r e n g t h m a t e r i a l s lack the d u c t i l i t y needed f o r c o l d heading Reactive metals i n high temperature a p p l i c a t i o n s must be coated, and coated fasteners w i l l not stand u p s e t t i n g B o l t s and
-214- screws of these m a t e r i a l s are expensive, but j u s t as s i g n i f i c a n t , the close tolerance holes they r e q u i r e are also c o s t l y t o produce The Panel f e e l s t h a t the development of new types of automatic and semi-automatic i n s t a l l a t i o n equipment f o r these fasteners i s needed and recommends t h a t t h i s subject be stu d i e d i n some depth This equipment might use high energy r a t e s of deformation and other new and novel techniques t o produce r e l i a b l e j o i n t s more e f f i c i e n t l y Adhesive Bonding The most c r i t i c a l problem i n adhesive bonding i s t h a t AARP requirements f r e q u e n t l y exceed the c a p a b i l i t y of present organic monomers Mach 3 and higher speeds w i l l r e q u i r e higher temperature adheslves C u r r e n t l y , new polymers of great e r thermal s t a b i l i t y are the types t h a t combine fused r i n g and aromatic hetero- c y c l i c f eatures (step-ladder polymers) F u l l y fused r i n g (ladder polymers) i s now g e n e r a l l y considered t o represent the most d e s i r a b l e form w i t h p o t e n t i a l s t a b i l i t y t o 1200 F Areas where present adhesive systems need improve- ment were i d e n t i f i e d and these are discussed i n various c h a r t s Special requirement areas i d e n t i f i e d are 1 Need f o r "wide-gap" adhesive t o reduce exacting requirements f o r f i t - u p 2 B e t t e r understanding of adhesive d e t e r i o r a t i o n w i t h time under s t r e s s a t temperature, e s p e c i a l l y on t i t a n i u m 3 Reduced dependence on p o t - l i f e of adheslves, p o s s i b l y by c u r i n g w i t h s p e c i f i c r a d i a t i o n r a t h e r than heat 4 Adheslves f o r use t o low temperature The high cost of s t i f f e n e d panels produced by weld- i n g , brazing or r o l l d i f f u s i o n bonding makes adhesive bonding extremely a t t r a c t i v e f o r f u t u r e weapons systems State of the a r t development w i t h adheslves such as those based on P I and FBI w i l l provide s o l u t i o n s t o some of the AARP problem areas but not t o those i n the most advanced categories A good 900 F adhesive w i t h 5000 p s l shear s t r e n g t h i s requ i r e d t o match the widening use of t i t a n i u m i n high speed s t r u c t u r e s
-215- D i f f u s i o n Bonding The r o l l d i f f u s i o n bonding programs recommended by the Panel are probably some of the most c o s t l y i n the e n t i r e CAMR spectrum But the p o t e n t i a l of t h i s process f o r producing I n t e g r a l l y s t i f f e n e d panels i s so good t h a t i t deserves s p e c i a l mention Present l i m i t a t i o n s m the f o r g i n g , e x t r u d i n g and r o l l i n g of high s t r e n g t h , r e a c t i v e and r e f r a c t o r y a l l o y s are too w e l l known t o be d e t a i l e d here Other means f o r e l i m i n a t i n g j o i n t s i n advanced designs need the broadest possible support The work supported by the A i r Force i n the middle- f i f t i e s , which r e s u l t e d i n the heavy f o r g i n g and e x t r u s i o n press program, brought immeasurable b e n e f i t s i n improved r e l i a b i l i t y , lower time and cost Now we are faced w i t h new f a m i l i e s o f metals and a l l o y s whose s t i f f n e s s or r e a c t i v e nature has brought the i n d u s t r y back t o the " b i t s and pieces" design era of World War I I Only through extensive government support can t h i s c o n d i t i o n be a l t e r e d and the designers of weapons systems be provided w i t h the advances e s s e n t i a l t o e f f i c i e n t s t r u c t u r e s B Outlook I n t h i s day of r a p i d l y expanding technology. I t i s not s u r p r i s i n g t o f i n d m a t e r i a l s and processes of i n t e r e s t t h a t are not i d e n t i f i e d by AARP, or i f so, only b r i e f l y The Panel has attempted t o t i g h t e n the gap by recommending programs covering those processes considered as o f f e r i n g the greatest r e t u r n f o r the broadest f a m i l i e s of m a t e r i a l s Other processes t h a t have not been s p e c i f i c a l l y recommended f o r study might show p o t e n t i a l i f developed f u r t h e r and these should not be neglected merely because they are not included i n the charts As examples, the Panel recommends a t t e n t i o n t o the f o l l o w i n g o I t i s hoped t h a t the b r i t t l e c h a r a c t e r i s t i c s of b e r y l l i u m w i l l f i n a l l y be overcome by a l l o y i n g and perhaps new production processes w i l l be developed t o produce a more i s o t r o p i c and d u c t i l e product Much study i s needed on j o i n i n g such a l l o y s w i t h o u t i m p a i r i n g p r o p e r t i e s t o any great degree The charts on welding, brazing and d i f f u s i o n bonding of b e r y l l i u m attempt t o define the needs o Explosive welding phenomena, p a r t i c u l a r l y f o r d i s - s i m i l a r metals and f o r t h i c k - t o - t h l n j o i n t s , are not c l e a r l y understood and deserve concentrated study
-216- The f l a s h r e sistance welding technique has been applied t o m i s s i l e cases w i t h good r e s u l t s Where the m a t e r i a l s permit, t h i s process o f f e r s a wide f i e l d of a p p l i c a t i o n ranging from small t h i n s t r u c t u r e s t o very massive ones, but study e f f o r t i s l i m i t e d today and requ i r e s expansion The f e a s i b i l i t y of spark s i n t e r i n g , t o create j o i n t s i n powder metals, has been p a r t i a l l y demonstrated I t would appear t h a t the whole f i e l d of e l e c t r o - magnetic energy, i n c l u d i n g very high energy r a t e s , might be examined f o r p o t e n t i a l i n s t i m u l a t i n g new j o i n i n g techniques The present extensive development work on composite m a t e r i a l s can be expected t o p o i n t up j o i n i n g problems There i s a d i s t i n c t need f o r the manufacturing s p e c i a l i s t s t o p a r t i c i p a t e i n the conceptual design study phase w i t h new composite m a t e r i a l s and prospective a p p l i c a t i o n s , and t h i s i s t r u e f o r both the A i r Force manufacturing s p e c i a l i s t s and those i n the aerospace i n d u s t r y To focus a t t e n t i o n on key manufacturing issues, such as equipment requirements, i t i s suggested t h a t AFML Manufacturing Technology D i v i s i o n prepare and issue an annual questionnaire covering I n t e r e s t s and a c t i v i t i e s of those develop- ing composites and the manufacturing problems i n d i c a t e d by c u r r e n t work As m a t e r i a l s get stronger they w i l l be used i n t h i n n e r gauges, and s t r u c t u r e s w i l l get l a r g e r The t o o l i n g , f i t - u p and d i s t o r t i o n problems f r e q u e n t l y quoted by AARP w i l l continue t o plague the i n d u s t r y u n t i l more study i s given t o them, and new t o o l i n g con- cepts are developed
217 TITLE ADHESIVE BONDING OF LARGE SANDWICH STRUCTURES CHART PRIORITY R E L A T E D C A M R C H A R T S 101. 70i, MANUFACTURING REQUIREMENT To manufacture large sandwich s t r u c t u r e s i n metal and p l a s t i c to p r e c i s e contours and to j o i n these to each other To obtain f i t up for bonding ( i e gaps l e s s than 0 010 inch) M a t e r i a l s are aluminum titanium s t e e l and beryllium metal to metal or with p l a s t i c honeycomb core AARP REFERENCES E r.â^. 153. 15A. 159. 178. 225 B C h a r t s . 84 85d 95a 96 98c 108b 112a b c PiFVPS C h a r t s . APPLICABLE PROCESS ADHESIVE BONDING C o d e 6 08 00 STATE OF THE ART ASSESSMENT There are two approaches to adhesive bonding large s t r u c t u r e s One i s to develop tooling to hold gaps to the required dimensions This has been done for small s i z e components and the problem for components as large as those r e f e r r e d to here (up to 50 foot diameters), i s l a r g e l y to be overcome by design of s o p h i s t i c a t e d tooling to be worked out for each i n d i v i d u a l part The s t a t e of the a r t i s considered adequate for t h i s approach but another approach involving adhesives with greater tolerance for gap distance warrants development F i l m adhesives where a g l a s s mat c a r r i e r i s used o f f e r one s o l u t i o n to t h i s problemn but are an i n e f f i c i e n t s o l u t i o n because a l l J o i n t gaps have to be increased and the excess adhesive with g l a s s f i l l e r adds weight throughout the s t r u c t u r e Foaming adhesives are a v a i l a b l e and w i l l provide a wide gap adhesive but have Inadequate strength Current adhesives have peak strength for gap widths i n the range of 0 005 inches to 0 009 inches and decrease i n strength above 0 010 inch gap CRITICAL PROBLEMS 1 F i t up St r u c t u r e s with compound curvatures and large R/t r a t i o s are d i f f i c u l t to p o s i t i o n for Joining J o i n t s of s k i n to core and J o i n t s between s t r u c t u r e s present f i t up problems to avoid buckling of s k i n ( s ) or core or adhesive voids due to excessive gap 2 Adhesive gap control Strength of an adhesive bond i s u s u a l l y a function of the adhesive layer thickness although the r e l a t i o n s h i p I s not c l e a r l y e s t a b l i s h e d and v a r i e s with circum stances (e g s t r e s s pattern) Above 0 010 inch (approximately) adhesive w i l l not flow into gaps so that voids may occur 3 Weight Use of f i l m adhesive to increase gap tolerance leads to exc e s s i v e weight and hence low j o i n t e f f i c i e n c y A Expansion Expansion of d i s s i m i l a r m a t e r i a l s leads to d i s t o r t i o n and/or excessive gaps I t may lead to l o s s of pressure during heat cure 5 Heat cure Attainment of uniform heat cure over e n t i r e s t r u c t u r e must be achieved to r e a l i z e uniform bond strength ALTERNATE PROCESSES NONE C o d e
218 CHART, ^ , NO i09 PROPOSED DEVELOPMENT PROGRAM OBJECTIVE The o b j e c t i v e of a development program w i l l be to provide an adhesive that w i l l flow into the standard gap yet flow equally w e l l i n gaps of much larger dimensions In t h i s way the weight penalty w i l l be minimal BACKGROUND I t i s recommended that a program be undertaken to develop adhesives more t o l e r a n t of J o i n t conditions p a r t i c u l a r l y j o i n t gap The development of "wide gap braze A s i m i l a r development for a l l o y s was a s i g n i f i c a n t advance i n brazing technology adhesives would provide more leeway i n the s o l u t i o n of some of the probl e m s o u t l l n e d above APPROACH The f i l m adhesives where a g l a s s mat c a r r i e r i s used o f f e r a s o l u t i o n to the problem but are an i n e f f i c i e n t s o l u t i o n because they provide excess adhesive throughout the s t r u c t u r e Goals for a "wide gap adhesive might be flow into gaps up to 0 030 inch with l e s s than 25 percent l o s s of strength at t h i s gap width compared with the optimum strength The flow c r i t e r i a should be by far the most important because voids decrease the strength more than represented by the area term as a r e s u l t of the s t r e s s r a i s e r s A two-phase program i s proposed Phase I Develop "wide-gap adhesives Examine various methods to promote flow i n wide gaps by c o n t r o l of v i s c o s i t y surface tension and other r e l a t i o n s h i p s Determine methods to c o n t r o l these param e t e r s by formulation and treatment of the organic adhesive Study e f f e c t of two phase adhesives with suspended m l s c l b l e and immiscible l i q u i d s and s o l i d s Study e f f e c t of p a r t i c l e shapes Adhesives should have s h e l f l i f e adequate for f a b r i c a t l o n of very large components Evalu a t e adhesives by t e s t s over a wide range of gap widths and with various s u b s t r a t e s Phase I I Develop processing procedures for sandwich s t r u c t u r e s Apply to a large s t r u c t u r e and conduct evaluation by d e s t r u c t i v e and non d e s t r u c t i v e t e s t s INSPECTION TECHNIQUES SUPPLEMEOTAL RECOMMENDATIONS INSPECTION REQUIREMENTS Measurement or p r e d i c t i o n of adhesive bond strength i n node J o i n t s of sandwich s t r u c t u r e s detection of unbonds between honeycomb core and faces and measurement of the degree of cure of the r e s i n used for bonding OBJECTIVE To develop inspection techniques to meet the above three requirements BACKGROUND P r e d i c t i o n of bond strength based on a d i r e c t non d e s t r u c t i v e t e s t does not appear f e a s i b l e An a l t e r n a t e and more I n d i r e c t approach to t h i s problem that w i l l be common to many aerospace systems i n the 1970 85 period i s being proposed by Chart 702 Hence that study i s d i r e c t l y a p p l i c a b l e to t h i s c h a r t Continued on next page
219 INSPECTION TECHNIQUES SUPPLEMENTAL RECOMMENDATIONS continued CHART , ^ N O Detection of unbonds between honeycomb core and faces Is possible using either pulse-echo (DAA) or through transmission (DAB) ultrasonics Both methods can be automated w i t h 100 percent scanning records I f required Infrared radiometric scanning (ECB) also shows promise for remote observations of unbond from r e l a t i v e l y large distances from the SO-foot diameter components This method requires soaking of the honeycomb structures at either elevated or sub-ambient temperatures then scanning the component surface with infrared radiometers f o r abnormal temperature ri s e s or lags that can be related to unbond conditions Determination of the state and uniformity of resin cure as a process con t r o l i s extremely d i f f i c u l t While d i e l e c t r i c (CDD) test methods Infrared spectroscopy (ECB) nuclear magnetic resonance (CBC) and microwave techniques (CDD above 10 glgacycles) show some promise considerable experimentation w i t h the exact resin formulation w i l l be required to obtain precise and repeatable process c o n t r o l data APPROACH Follow closely the r e s u l t s of the adhesive bond strength test program described i n Chart 702 The resu l t s should be d i r e c t l y applicable to t h i s problem Test specimens with varying degrees of unbond should be examined by pulse echo through-transmission and Infrared methods The preferred method should be selected and procedures established based on t h i s evaluation of a l l three methods Samples of the structure with undercured normally cured and overcured resin should be provided for comparison tests by d i e l e c t r i c and microwave methods Again the preferred method should be selected and procedures established based on t h i s evaluation
2 2 0 PRIORITY RATING WORKSHEET CHART P R O f i R A M F A C T O R S PROGRAM PROBABIL ITY OF S U C C E S S D LOW Z yO. MODE RATE 5 ⢠HICH 8 CRIT ICAL P R O B L E M S TO B £ SOLVED U p e W / N O T TOO DIFFICULT Z ft S O M E / D I F F I C U L T 3 a M A N Y / VERY DIFFICULT 8 P R O C e S S G R O W T H P O T E N T I A L ⢠LITTLE OR. UNDEFINABLE O 'X li£co6Haj>&i-e porsMTiAL 4 APPLICATIONS OTHER. THAN AIR FORCE ⢠NONE O a SOME 4 H MANY 0 N E C E S S I T Y FOR AIR FORCE F U N D l U a ⢠LOW Hifix i N t u s T s v / c r m e A <30«r C F F o a r li- ft, IKeOCAATE - SCMC E F n c r OTHCS 'SOUOtieS e ⢠t*£ms\<ie AiK FefteL punpMa U K E L V 14. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH P B O B A B I L I T V FAIR P R O B A B I L I T Y LOW P R O B A B I L I T V COMPONENT C R I T I C A L I T Y V E R Y H I ^ H FAIR L o w F R E f l U E N C Y OF REQUIREMENT IN S Y S T E M M e H £ THAN 3 CoMPOHfeUTS i 3 CeMPtMENTS S l u a L E CeMPeNENT DeSlGN A L T E R M A T e S No ALTERNATE R W E B E E N O N t ALTERMAre S E V E R A L A L T E R U A T e C M A T E K I A L S IMPLICATION New MATERIAL PeV£U)f»l£NT RCO O PWTeKlAL IMPftOVEMeWT R E S D NO PROSLEM F o R C S e e k l 5e R A W S C O R E S FOR EACI4 REFteeMrtP COMPOWttfT IN TABLKS AT t*»l> or P A M E L 12tP«tT W I T H TZAVO T O T A L S E N T C R C P M SUMMAKV AT tZlSMT S V . T . . , AARP RA>N SCORES i T i r a ^ r ^ i II B Za 6) a n n u a l « i f f ⢠⢠⢠⢠CALCULATE PRIORITY- S T E P t CIRCLE HIGHEST AARP RAW SCORE m S T t P Z IN eACH OfHER S V S T 6 M C IRCLE NEXT HIGHEST SCORE 36 IF WITHIN NUMBER OF 4 P O I N T S ⢠S y s T E M S HIAH O F T O P LOW S C O R E STEP 3 CIRCLB NUMaeR. OF S Y S T E M S LOW FREOUENCY DISTRIBUTION FACTOR NUMQen. OP s y s r C M S mart B E U O W i 0 I 2 RMOtt 1 0 1 a 1 4 1 1 1 3 1 f 1 z 1 4 ] ⢠⢠⢠⢠] ⢠⢠⢠⢠] ⢠⢠⢠⢠] ⢠⢠⢠⢠] ⢠⢠⢠⢠] ⢠⢠[ ! SI 2 TOTAL PRIORITY
221 TITLE BRAZING LIGHT METALS MAGNESIUM AND BERYLLIUM CHART NO PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Join l i g h t weight assemblies of magnesium and beryllium by brazing for service at moderate temperature In a space environment Applications Include spacecraft enclosures and supporting structure solar c o l l e c t o r s antenna space radiators advanced extravehicular space s u i t s and drag entry control surfaces AARP REFERENCES E rhnrt. 216 288 B Char ts . 107d 108a 109b 111b 134a 172a 176 P&FVPS Char ts . APPLICABLE PROCESS One of the following depending on end Items (1) ELECTRIC BLANKET (2) FURNACE BRAZING (VACUUM AND RETORT) (3) RESISTANCE HEATING OF CERAMIC TOOLS (A) RADIANT LAMP HEATING (5) IMMERSION Code 6 05 11 6 05 01 6 05 04 6 05 03 STATE OF THE ART ASSESSMENT Magnesium Magnesium and beryllium based alloys are especially a t t r a c t i v e In the aerospace Industry due to t h e i r low density The use of magnesium Is li m i t e d by problems with poor corrosion resistance poor w e l d a b l l l t y and f i r e hazards A wide v a r i e t y of magnesium alloys are available These alloys f a l l In natural groupings based on t h e i r application Two examples are HK 31 for elevated temperature strength (dispersion strengthened) and LAIAIA for extremely l i g h t weight (new Mg L I series) The use of brazing processes for assembling magnesium structures has been quite l i m i t e d Most of the early e f f o r t s were confined to the brazing of magnesium MlA al l o y (nearly pure contains only 1 5% Mn) due to the high melting point of the only available f i l l e r materials More recently success has been noted In brazing the aluminum zinc (AZ 31) and zinc rare earth (ZE 10) magnesium alloys using chloride base fluxes with a Mg Al Zn brazing a l l o y Experiments with small additions of beryllium to the brazing a l l o y have shown marked reductions In oxidation of the molten pool and hence a reduced f i r e hazard problem The most useful brazing alloys evaluated to date flow In the 1080 1100 F range and show useful strength to 300 F Some success i n using solders with precoated magnesium (no f l u x ) has been reported The most successful precoatings have been Sn Zn alloys The best solders have been Cd Zn Sn which flow around 550 F Beryllium Alloys Beryllium exhibits some t r u l y outstanding advantages but i t also has serious deficiencies The advantages include i t s high modulus (1 6 x that of steel) high melting point (2 x that of the other l i g h t metals) and good oxidation resistance to 1500 F The disadvantages include a high degree of d i r e c t i o n a l i t y with very low d u c t i l i t y i n the short transverse d i r e c t i o n a t o x i c i t y problem when thermal processing or dust is involved and very high cost Due to d i f f i c u l t i e s i n welding e f f o r t s to apply the brazing process to beryllium have had a f a i r share of the a t t e n t i o n i n t h i s f i e l d of materials Most of the e f f o r t s have been Continued on nex^^ag^^^^_^_^^ ALTERNATE PROCESSES NONE Code
222 STATE OF THE ART ASSESSMENT, continued CHART , concerned with Ag base alloys w i t h lesser e f f o r t s using Al or T i base alloys Good wetting and Joint strengths have been reported especially with Ag L i alloys The use of T i vapor deposits on the beryllium has been shown to improve the wetting c h a r a c t e r i s t i c s of cert a i n alloys considerably The roost promising alloys evaluated to date Include the following A R Base Al Base T i Base (1) Ag Al Mn (1) Al Si (1) T I Cu In (2) Ag L i (braze around (braze around (3) Ag Be 1100 F) 1700 F) (4) Ag-Cu-Ni (braze around 1600 F) Small honeycomb sandwich structures have been brazed successfully These promising results warrant further e f f o r t s CRITICAL PROBLEMS ~ Development of brazing alloys for magnesium and beryllium are required Basic magnesium or beryllium a l l o y development is not recommended as a part of t h i s materials area Magnesium Brazing The a p p l i c a t i o n of brazed magnesium structures such as honeycomb sandwich i n the large quantities required w i l l necessitate development e f f o r t s i n two areas brazing a l l o y development and low cost brazing process development The development of brazing alloys s p e c i f i c a l l y for use wit h magnesium i s s t i l l i n i t s Infancy A program to develop a useful a l l o y w i l l therefore have to s t a r t at the beginning The major problem to be considered i s the flow temperature With a melting point of 1200 F(Mg base metal) to be considered the l i s t of al l o y systems i s somewhat l i m i t e d Low melting point eutectlcs must be considered A careful evaluation w i l l be necessary to f i n d acceptable elemental combinations which have the desired flow temperatures and yet possess useful elevated temperature strength Other factors Include d i f f i c u l t i e s w i t h surface osides the f i r e hazard generated with oxygen reacting with the molten magnesium pool and corrosion resistance Beryllium and Beryllium A l l o y Brazing * The major problem area hindering the commercial application of brazed beryllium structures i s the lack of a suitable brazing a l l o y From exploratory studies i t i s assumed that present brazing processes already developed or under development w i l l be applicable The p r i n c i p a l new factor i n processing w i l l be the health hazard which is associated w i t h Inhalation of BeO or f i n e l y divided Be dust Close con t r o l of i n e r t gas or vacuum processing w i t h an emphasis on t h i s problem can meet the required needs The development of a brazing a l l o y must consider several problem areas including the following Poor w e t t a b i l i t y of beryllium gamma phase ( b r i t t l e with s i l v e r brazements) trans formation above 1500 F strong tendency of beryllium to form In t e r m e t a l l l c s high d i f f u s i o n rates w i t h other metals and the need for a low density brazing a l l o y PROPOSED DEVELOPMENT PROGRAM PROGRAM I Magnesium OBJECTIVE The objective of t h i s program is to develop a low temperature high f l u i d i t y brazing a l l o y for magnesium which can be used without a f l u x APPROACH An exploratory type brazing a l l o y development program should be undertaken The brazing temperatures should be i n the 500 750 F range The service temperature Continued on next page
223 Program I Magnesium, continued Approach, cont d should be to 450F C H A R T N O T 4 < ? OBJECTIVE APPROACH Several commercial magnesium alloys are f i n d i n g aerospace usage without a single candidate receiving emphasis Several d i f f e r e n t families of alloys can be selected depending upon the most important usage requirements such as elevated temperature strength extra low density c a s t a b i l l t y etc For t h i s reason the evaluation should consider a representative a l l o y from each category AZ 31 (general use) HK 31 (high temperature strength) LA-141A (extremely low density) are recommended The following s p e c i f i c requirements should be emphasized a Brazed Joint shear strength at room and anticipated service temperature b Corrosion and oxidation resistance of the Joints c Extent of the erosion problem for use with t h i n gauge base material (heat exchangers etc ) d W e t t a b i l i t y and f l u i d i t y f o r brazing of complex assemblies e Thermal conductivity f Low density I t i s assumed that e x i s t i n g proven brazing processes can be u t i l i z e d These Include furnace brazing e l e c t r i c blanket brazing quartz lamp brazing torch brazing and others The development e f f o r t s should be directed toward one or more of these processes PROGRAM I I Beryllium & Beryllium Alloys The objective of t h i s program i s to develop a low density brazing a l l o y for beryllium and I t s alloys which can be used without a f l u x requirement I t should be aimed at commercial usage as soon as possible A comprehensive brazing a l l o y development program should be undertaken l i m i t a t i o n s should be established a Flow temperature below 1600 F b Good w e t t a b i l i t y without the use of f l u x c Minimum d i f f u s i o n and i n t e r m e t a l l i c formation d Density l i m i t e d to 0 2 Ib/cu i n maximum The following Some work i n t h i s area i s now under way basic information on promising braze a l l o y programs For Instance l l t h l u i a additions in acceptable w e t t a b i l i t y Other elements to react s i m i l a r l y The b r i t t l e n e s s resul l i m i t i n g the permissible flow temperature the l i s t of candidate elemental additions of i n t e r m e t a l l l c s and high d i f f u s i o n rates diagrams d i f f u s i o n data and metallograph I t should be continued and expanded Some constituents is already available from past to brazing alloys have been shown to r e s u l t such as Be i t s e l f B or In may be expected t i n g from gamma formation may be avoided by Such l i m i t a t i o n s however l i m i t somewhat The problem associated with the formation w i l l require c a r e f u l studies of phase ic studies of d i f f u s i o n couples To s i m p l i f y the investigation a single beryllium product should be evaluated Vacuum hot pressed sheet (QMV) i s recommended for the Investigation A commercial brazing a l l o y and process for beryllium could greatly Increase the aerospace usage of beryllium Should a sizeable usage for the new Be Al alloys materialize i n the near future they too should then be Included Continued on next page
- 2 2 4 Program I I - Beryllium & Be Alloys, continued CHART NO H^O The following s p e c i f i c requirements should be emphasized a W e t t a b i l i t y and f l u i d i t y without the uee of f l u x b The e f f e c t of surface pre treatment of the Be c Brazed Joint shear strength at room and anticipated service temperatures d Brazed Joint peel strength e Brazing a l l o y e f f e c t s on the base metal properties f Extent of the base metal erosion problem g Thermal conductivity h Density of the brazing a l l o y 1 Corrosion and oxidation resistance
2 2 5 PRIORITY RATING WORKSHEET CHART PRQfi^pAM FACTORS PROfiRAM PROBABILITY OF S U C C E S S D ⢠L O W 2 TA M O D E R A T E 5 ⢠⢠HICH 8 C R I T I C A L P R O B L E M S TO B E SOLVED ⢠⢠p e W / N O T TOO D I F F I C U L T Z "AfC S O M E / D I F F I C U L T S Q Q M A N Y / V E R Y P IFPjCULT 8 P R O C E S S G R O W T H P O T E N T I A L "JA a LITTLE OR. UNDEFINABLE O ⢠X f!£C06HtlH»te PorEMTiAL 4 APPLICATIONS OTHER TWAN AIR FORCE ⢠⢠N O N E O ys ⢠SOME 4 ⢠K MANY 0 N E C E S S I T Y FOR AIR FORCE F U N D I N O D n LOW HISH IMPUSTItV/eTHeA Cff 4 r l^ ⢠Ji MSOtSATE - S t M E S F f o t T OTHce. 'SOUC/ieS e K ⢠ex£UlsiyE A IK f't£t fuuvua UKCL>< If. NEED FACTORS S Y S T E M S P F I D B A B I L I T Y HIQH P B O B A B I L l T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y COMPONENT C R I T I C A L I T Y VERY HICH H I A H F A I R L o w F R E f l U E N C Y OF R E a u i R E M E N T IN S Y S T E M MARE THAN 3 C0MP»«<EMT9 Z 3 CtfMPeHENtS S INf lLE CeWPeNENT DES)6N A L T E R N A T E S No ALTERNATE R W E S E E N ONE ALTERNATE S E V E R A L A L T E R M A T E C MATERIALS IMPLICATION New M A T E R I A L DtV U jFMtMT CEO O MATERIAL IMPHOVtMtWT E E S P NO P R o a L E M F o K c s e e i a CALCULATE PRIORITY P R O G K A M 3 2 ^ 3o RAW SCoflES FOR E A C H R E F E K E N f t P COMPONCMT IN T A B L E S AT t f J D or P A N E L WITH PAIO T O T H L S E N T E R E P na â¢SUMMAeV AT S V S T E K I S SZe AARP RAva scones B3£ I J O " ! I To I STEP I CIRCLE HIGHEST AARP RAW SCORE n s S t e p 2 IN eACH OTHER SVSTeM CIRCLE NEXT HKSMEST IF WITHIN ^ POINTS OF TOP SCORE n NUMBER OF SYSTEMS HidH ^ LOW ^ 3£, SCORE STEP 3 CIRCLE FREQUENCY DISTRIBUTION FACTOR f BELOWi NUMsen. ot s y s T S M S 3 OK M««E N U M & E R OF S Y S T E M S LOW 0 I 2 B-MOtt 1 0 1 a I 4 1 1 1 3 1 z 1 4 i r n I I I ⢠⢠⢠C i n ⢠⢠⢠L I I 1 I I 1 ⢠⢠⢠⢠⢠⢠⢠L I I 1 I I 1 ⢠⢠⢠c : l U ⢠⢠⢠⢠I I 1 ⢠⢠⢠⢠⢠5 5 33 TOTAL PRIORITY ( j ) ©
226 TITLE FUSION WELDING BERYLLIUM AND BERYLLIUM ALLOYS CHART NO PRIORITY R E U T E D CAMR CHARTS MANUFACTURING REQUIREMENT Join by fusion welding d e t a i l s of beryllium and beryllium alloys to produce pressure t i g h t s t r u c t u r a l welds for large spacecraft structures up to AO feet of s t i f f e n e d skin or sandwich panel construction large solar c o l l e c t o r s and antennae up to 60 foot diameter with edge members and s t i f f e n e r s holding very close surface contour tolerances and s o l i d propellant rocket motor cases for upper stages 10 feet diameter spherical with 0 400 inch wall thickness or ICBM motor cases approximately 30 Inch diameter by 5 feet long with 0 125 inch w a l l t h i c k ness These applications are a t t r a c t i v e because of the very low density for beryllium but presuppose adequate t r l a x l a l d u c t i l i t y for the application w i l l be developed AARP REFERENCES E Charts B Char ts . lQ7a. d. e. 108a. c. 109b. l l l a . b P8FVPS Char ts . Joining No 13 APPLICABLE PROCESS One of the following depending on end Item TIG ELECTRON BEAM LASER 6 01 0?"" 6 01 12 6 01 15 STATE OF THE ART ASSESSMENT A great many aerospace companies and laboratories are involved i n developing production welding processes of beryllium and assessing the strength and fatigue c h a r a c t e r i s t i c s of the welds produced Products include cross r o l l e d and Ingot sheet and several grades of pressed block The oxide (BeO) content which contributes to the strength of the various grades affects w e l d a b i l i t y At the same time the b r i t t l e c h a r a c t e r i s t i c of beryllium does not contribute to d u c t i l e welds Add to t h i s excessive grain growth cracking under r e s t r a i n t and the toxic nature of beryllium vapors^and the conclusion may be drawn that fusion welding of beryllium i s not a production process and beryllium as presently produced needs much study to determine which course to pursue to a r r i v e at a more weldable product B a t t e l l e and others have studied the ef f e c t s of impurities on weld properties and there i s much resea c h i n c r y s t a l l o g aphy and i n a l l o y ng t o modify t h e basal s c u c c u e w h i c h ho I d contribute t o a more weldable material There is only one commercially available beryllium a l l o y (Be 38A1) but again there is a sizable amount of work going on The al l o y available is much more weldable and parent metal strengths i n TIG and EB welds have been reported For both Be and the a l l o y most work has been done on r e l a t i v e l y t h i n sheet and data on heavier gauges o f plate i e 1/A inch and up and block i s meager Most of t h i s i s for the EB process TIG and MIG braze welding have been done using Al Si Ag based and Che beryllium a l l o y as f i l l e r s TIG and EB welding o f beryllium and the al l o y have been accomplishec' w i t h and without beryllium and a l l o y wire In both cases results vary with the techniques tools and speeds used Preheat has been found e f f e c t i v e in welding restrained j o i n t s AL2O3 overlays have been e f f e c t i v e insulators on back up and hold down tooling Welding speed has been found to be very c r i t i c a l for both TIG and EB Although investigators d i f f e r on the r e l a t i v e merit of AC and DC Con t ^ n u e ^ ^ i ^ j T e x ^ j i a g ^ ALTERNATE PROCESSES MECHANICAL FASTENING RESISTANCE WELDING Code 6 11 00 6 02 00
227 STATE OF THE ART ASSESSMENT, continued CHART , â NO V i t f power supplies I t le apparent from the l i t e r a t u r e that the AC supply compensates for Inadequate cleaning and shielding by reason of the cathodlc etching associated with the reverse p o l a r i t y arc However weld width current magnitude and energy Input are s u b s t a n t i a l l y greater for a given welding speed as compared wi t h the DC supply and therefore the mechanical proper t i e s are lowered I t appears that cracking would be minimized and mechanical properties optimized f o r TIG welding by u t i l i z i n g a precision DC supply e x h i b i t i n g minimum possible r i p p l e together with e f f e c t i v e cleaning procedures With EB welded In a hard vacuum (10~^Torr approximately) beryllium welds e x h i b i t Joint e f f i c i e n c i e s of 65 percent at room temperature and 100 percent at lOOOF As previously stated the Be 38A1 a l l o y has been welded w i t h 100 percent Joint e f f i c i e n c y recorded when tested at room temperature The use of chambers and shields Is today mandatory due to the vaporization which occurs Shielding or l i n i n g of chambers or the use of tents Is essential to avoid contamination of the equipment and work area by vapor deposition I n conclusion there i s Intensive work afoot to understand the nature of beryllium and I t s alloys and i t must continue I f they are to be accepted as proved engineering materials Welding studies must continue as an important part of t h i s work and requires extensive govern ment support CRITICAL PROBLfMS 1 Basic materials study of c r y s t a l nature and a l l o y i n g to Improve mechanical properties d u c t i l i t y and amenability to welding processes 2 Excessive grain growth cracking undercutting d i s t o r t i o n must be controlled as w e l l as the vapor phase with i t s problems of t o x i c i t y and contamination 3 Systems of adequate power control and an understanding of the variables a f f e c t i n g weld strengths and defects ^ E f f e c t i v e and economical surface oxide removal techniques needed p r i o r to welding I PROPOSED DEVELOPMENT PROGRAM OBJECTIVE BACKGROUND APPROACH To study basic fusion welding parameters for beryllium and beryllium alloys and to develop Joint strength data w i t h i n the l i m i t a t i o n s of the parent material The s t i f f n e s s and l i g h t weight of beryllium make i t extremely Interesting to designere of aerospace structures There i s much R&D i n work to improve i t s b r i t t l e nature and Increase mechanical properties by a l l o y i n g and r e f i n i n g The curren t l y available beryllium products do not e x h i b i t good welding c h a r a c t e r i s t i c s and welds are subject to grain growth and cracking When c a r e f u l l y c o n t r o l l e d welds e x h i b i t i n g very close to parent metal strength can be achieved i n beryllium and i t s alloys i n the labora- tory but there are many problems to overcome before fusion welding can be considered a production process A program should be i n i t i a t e d to reduce the welding of b e r y l l l i m and ber y l l l u n i alloys to a production process This should include HP block cross r o l l e d sheet ingot sheet the l a t e s t high strength sheet and al l o y s i n block and sheet and experimental alloys as developed This program would lay the ground-work for the time when Improved material i s r e a d i l y available and would stimulate the needed work In parent metal Improvement Phase I A l i t e r a t u r e survey should be conducted for the purpose of consolidating the available data i n a form suitable for evaluation This should Include the work of the B r i t i s h on Fe Al r a t i o s of B a t t e l l e on the influence of impurities In weld r e s u l t s and of IITRI on eddy currents and ultrasonic s t i r r i n g of the molten pool to break up dendrites Other work of similar nature should be included The f i n a l report should Include recommended e f f o r t i n succeeding phases Continued on next page
-228 PROPOSED DEVELOPMEWr PROGRAM, continued CHART , â NO "/Ai Phase I I Using beryllium and beryllium alloys of current i n t e r e s t an i n i t i a l study directed toward Improving the process sha l l be conducted This program should include but not be l i m i t e d to 1 A study of supplemental methods for improving weld metal grain size c o n t r o l Ultrasonic and eddy current methods to be investigated as we l l as super cooling and other means High speed and IR photography w i l l be useful tools i n t h i s Investiga t i o n 2 A study of the e f f e c t of welding process variables on weld properties The welding study w i l l be conducted by electron beam welding at a pressure of 100 microns Variables to Include welding speed power density and locus of focal plane Beryllium and beryllium a l l o y s h a l l be selected for these tests on the basis of Impurity l e v e l and r a t i o s 3 Study and determine the role of various Impurities and a l l o y additions on defects such aa hot tearing and cracking and on grain size under controlled welding conditions NOTE 1 To reduce costs of t h i s phase and to broaden the base of understanding of weld variables selected aluminum alloys such as 6061 may be used i n the i n i t i a l studies and fallowed by application to the beryllium products selected NOTE 2 Consideration should also be given t o the use of u l t r a h i p u r i t y beryllium as a yardstick i n assessing the e f f e c t of the impurities as described i n 3 above Phase I I I Selected sizes of beryllium and beryllium a l l o y products and grades shal l be welded and tested Selection s h a l l be based on impurity levels and r a t i o s w i t h p a r t i c u l a r a t t e n t i o n to the amount of BeO present Both butt welds and other t y p i c a l production type j o i n t s s h a l l be investigated The experiments s h a l l be conducted for both TIG and EB processes and the CW laser i f proved at t h i s point i n time When c r i t i c a l parameters have been i d e n t i f i e d and control l e d the use of various f i l l e r s and weld braze materials s h a l l be Introduced to determine i f further improvement res u l t s
229 PRIORITY RATING WORKSHEET CHART PRQgRAM FACTOttS. PROGRAM PROBABILITV OF S U C C E S S ⢠LOW Z yl M O P E R A T E 5 ⢠H IAH 8 CRIT ICAL P R O B L E M S TO B E SOLVED ⢠FSViyUOr TOO D1FFU?ULT Z ^ S O M E / D I F F I C U L T 3 a M A N Y / VERY DIFFICULT 6 P R O C E S S G R O W T H P O T E N T I A L ⢠LITTLE O R UNDEFINABLC O ft ttSOeNIMBLE PerCMTIAL 4 APPLICATIONS OTHER THAN AIR FORCE ⢠NONE O ⢠SOME 4 X MANY 8 N E C E S S I T Y FOR AIR FORCE FUNOINQ ⢠LOW H\6H INPUSTHV/eTHtft GOVT C F F T C T t ]fL rxcoecATs - ^ o N E EFMiLr erHca. N u e c e s s Pa NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH PROBABI l - i rY IZ FAIR P R 0 6 A B I L I T Y 8 LOW P R O B A B I L I T Y 4 COMPONENT C R I T I C A L I T Y VERY HKTH 14 HIAH 9 FAIR 6 LOW 3 F R E a u E N C y OF R E Q U l R E M E N r IN « V « r e M mnc THAN 3 ceMP»*ieHT9 3 4 3 COMPeNEurs 2 S I N f i L E <SeMP«NeNT I DESIGN A L T E R W A T E S No ALTERNATE R M E e e E N 9 ONE AUTEBNATE 6 S E V E R A L A L T E R N A T E ? 3 M A T E R I A L S IMPLICATION New MATe«2.|AL PeveLO^MCNT RCA O 6 MATERIAL IMPlU>VEMCNT R E A P 4 NO P R o a t e M F o n e s e e N o STEP STEP I 8 8 So RAW S C o « S F O R E A C H R E F C R E i K l P CoMFf lNtNT IN TAOLUS AT bND or P A N E L « t P « t T UI ITH C A M ToTrtts E N T E R C P M AT tZlSHT S V S T e M S AARP RA>M seoees ⢠⢠I I C ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠CALCULATE PRIORITY CIRCLE HIGHEST AARP RAW SCORE IN EACH cn-HER S V S T 6 M CIRCLE NEXT 36 IP WITHIN N U M S 6 R eF POINTS S V S T E W S HldH OF TOP ? LOW HIOM£ST SCORE n STEP 3 CIRCLE FREOUENCY DISTRIBUTION FACTOR NUMsen. OP s y s T C M i s rtisM I 2 . 3 e a MMLC S C O R E BELOWi NUMaeR O F S Y S T E M S L O W 0 I 2 n M o e c 1 0 1 a » 4 1 1 1 3 1 I f 1 £ (r4>, 1 4 SO.'/ TOTAL PRIORITY
-230 r TITLE PRECISION ADAPTIVE CONTROL OF WELDING PROCESSES FOR ADVANCED AEROSPACE MATERIALS CHART PRIORITY RELATBD CAMR CHARTSi HAt MANUFACTURING REQUIREMENT Weldments are required of a wide v a r i e t y of alloys such as re f r a c t o r y metals superalloys titanium and dispersion hardened alloys Raw products range from f o i l gauges through sheet plate extrusions and forglngs The geometry of the assemblies to be Joined is generally large and of variable contour with diameters Co 50 f t and lengths to 160 f t Environments are h o s t i l e i n which l i f e spans to 30 000 hours are demanded NOTE Recommendations of t h i s CAMR chart are incorporated by reference In the following charts 402 415 424 425 428 430 435 445 446 447 AARP REFERENCES E Charts B Char ts . PAFVPS Char ts . APPLICABLE PROCESS TO BE APPLIED TO TIG MIG EB RESISTANCE AND NEWLY EMERGING PROCESSES Code STATE O F THE ART ASSESSMENT Fusion welding has evolved from a manual process depending on the s k i l l of the welder to an automatic process r e l y i n g upon the precision of the welding apparatus control systems together w i t h rigorously applied q u a l i t y control procedures I n t r i n s i c with the application of welding apparatus of improved precision has been the dependence upon non l e t t r u c t l v e t e s t i n g to locate defects of dimension and character which would cause c r i t i c a l stress concentrations and consequently low energy catastrophic fracture or propagation of fatigue fracture Radiographic and ultrasonic testing methods however are less sensitive and less r e l i a b l e than desired p a r t i c u l a r l y i n th i c k sections Furthermore such inspection methods can do no more than locate a defect a f t e r i t has been created The problem then i s to make a repair which I t s e l f does not degrade the structure A p o t e n t i a l s o l u t i o n appears to be i n the development of welding control systems which automatically sense a l l rhe process variables and continuously optimize the c o n t r o l l a b l e input parametors In order to maintain an optimum l e v e l of process performance Such yfitems are referred to as adaptive and the f i r s t elementary adaptive controls have already been developed for several of the welding processes 1 Penetration control for TIG welding This system is based upon a welding mode In which the tungsten electrode i s positioned below the surface of the work piece by the arc voltage contr o l l e d head when welding f a i r l y heavy gauges wi t h r e l a t i v e l y high currents This welding mode is characterized as high power density TIG welding and the resultant Jet forces of the arc plasma depress the molten puddle rhe adaptive control system was developed af t e r observing that (with a given welding current arc voltage welding speed material and Joint configuration) the tungsten electrode moved u p w n r d away from the work when penetration decreased and downward toward the work when peiiccration increased This observation was investigated and found to be a general rule independent of the cause of the change in penetration Thus penetration would decrease i f a massive heat sink were clamped in the v i c i n i t y of the Joint or as a tack weld were approached or Che plate thickness Increased In either case associated with the decrease in penetration was the movement of the tungsten electrode oway from Che work by the action of the arc voltage Continued on next page ALTERNATE PROCESSES NONE Code
231- CHART N O V 3 J STATE OF THE ART ASSESSMENT, continued contr when the e Penet accur elect or de set V and c penet ol i n maintaining the pre set value of arc voltage Conversely penetration Increased the heat sink was removed the j o i n t gapped and the thickness reduced Simultaneously lectrode would move toward the work As a re s u l t of these observations the Arc rat i o n Control shown In Figure 1 was developed The sensor is simply a device which at e l y measures the r e l a t i v e location of the welding torch (and thus the tungsten rode) w i t h respect to the surface of the work The adaptive c o n t r o l l e r acts to increase crease the welding current such that the measured r e l a t i v e location is maintained at a alue The system is v a l i d for TIG welding and for gauges of at least 1/8 thickness o n t r o l s only weld penetration I t can thus eliminate two classes of defects I n s u f f i c i e n t r a t i o n and lack of fusion at the root of m u l t i pass or opposed welds SENSOR POWER SUPPLY WELDING T O R C H ARC CURRENT WELDING D C POWER SUPPLY OSCILLATOR DISCRIM- OUTPUT INATOR NETWORK S E T - l t ^ POINT ^ L . PHASE SCR SHIFT POWER STAGE FIGURE 1 PENETRATION CONTROL BASED UPON TUNGSTEN ELECTRODE POSITION 2 Penetration Control for TIG, MIG and Fusion Spot Welds This system is based upon IR measurement at the underside of the j o i n t I t is used to varj c i r r nc to maintain constant penetration i n TIG welding t r a v e l speed (or current) i n MIG and welding time in fusion spot welding I t is shown schematically i n Figure 2 The sensor requires access to the back side of the j o i n t 3 Resistance Spot Welding Adaptive Control This system was conceived a f t e r observing that the a r t i c u l a t e d electrode of an air operated resistance spot welder moved upward as the weld is formed I t was then reasoned that the change in state from s o l i d to l i q u i d accompanied as I t is by an increase in vol me results i n an extremely high local expansion force which i s exerted against the electrodes The electrode force system is e l a s t i c thus the expansion force of the change in state pushes the a r t i c u l a t e d electrode upward u n t i l e q u i l i b r i u m is reached Hence the motion of the electrode IS a measure of the volume of metal melted An extremely sensitive device was designed to measure t h i s motion This measurement is fed to an adaptive c o n t r o l which compares the motion attained with the desired value and Interrupts the welding current at correspondence Certain constraints are incorporated i n the system design This system is i l l u s t r a t e d i n Figure 3 Continued on next page
232 CHART NO i33 POWER SUPPLY DC AMPL > > WELDING TORCH ARC CURREirr r IR SENSOR D C WELDING POWER SUPPLY OUTPUT CIRCUIT SET- poiwr AMPl FHASF SCR SHIFT POlrtIR STAGE I FIGURE 2 PENETRATION CONTROL BASED UPON IR MEASUREMENT POWER SUPPLY OSCILLATOR DIFFERENCE DETECTOR AMPL 7 1 ^ LEVEL DETECTORS SET POINTS FIGURE 3 . RESISTANCE WELDING ADAPTIVB CONTROL WEI D THE WELDER CONTROL VISUAL DISPLAY Continued on next page
-233- CHART HO-MIA CRITICAL PROBLEMS The q u a l i t y of a welded j o i n t i s the r e s u l t of the i n t e r a c t i o n of a number of factors some of which are rigorously controlled some p a r t i a l l y controlled and some uncontrolled For example consider the case of TIG (GTA) welding The parameters controlled by the modern automatic welding apparatus are regulated with precision These are welding current arc voltage wire feed speed and weld t r a v e l speed tach system u t i l i z e s a closed loop control and the output value of each function corresponds very closely w i t h the set val e The variables which are r e l a t i v e l y loosely controlled include j o i n t f i t up and mismatch Uncon t r o l l e d variables include ambient temperature and r e l a t i v e humidity Automatic welds are made u t i l i z i n g set up parameters determined by performing welding tests with simulated assemblies Nevertheless a welder must monitor the welding operation and attempt to make appropriate on l i n e modifications to pre set parameter values as he is able to perceive need to do so The most frequently encountered causes for variations in penetration in the j o i n i n g of large booster segments for example are va r i a t i o n s in mismatch j o i n t gapping tack welds and local heat sinks Incomplete penetration is only one of the weld defects encountered i n practice Porosity cracks, lack of fusion and undercut are other defects found in welded j o i n t s These defects were obviously avoided i n the development of the process control and parameter-setting values 111 the simulated production j o i n t s In a general sense therefore weld defects are caised b> varianons betieen the process input variables obtained under controlled laboratory environ nenfs and those obtained i n production environments Consequently the process performance can be j,reatly improved by continuously monitoring the process with an automatic c o n t r o l l e r of adeqiate perception and response Adequate perception means the u t i l i z a t i o n of sensors which w i l l feed back sensible data which represent a measure of the process performance Adeqiate response in t h i s context means that the c o n t r o l l e r w i l l make appropriate corrections to the controlled input parameters i n order to compensate for the uncontrolled variables and maintain process performance at some optimum level Such a system would in e f f e c t close the loop between the weldment and the welding apparatus The function of the adaptive control is to vary one or more of the controlled input variables In order to compensate for uncontrolled variables and thus to maintain process performance at some desired lev e l To return to a spec i f i c example i n the case of TIG welding t h i s Implies that welding current is Increased or t r a v e l speed reduced as weld penetration s t a r t s to decrease However such compensating changes i n parameters cannot be done indiscriminately Considerations of the metallurgy of the material being welded may require imposing a l i m i t on the energy input This becomes a constraint on the process parameters which must be respected by the adaptive control For a given arc voltage and shielding gas there is a li m i t e d range of arc current at which a stable arc is produced This imposes another constraint In MIG (GMA) welding there is a narrow range of current at a given wire feed speed at which spray transfer is maintained This is s t i l l another constraint that must be observed Additional examples can be cit e d for the various fusion welding processes The aiaptive c o n t r o l l e r therefore must generate correction commands to optimize welding process performance without v i o l a t i n g the constraints placed upon the system Continued on next page
234 CHART PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop and evaluate under variable conditions and w i t h d i f f e r e n t c r i t i c a l alloys sensors which can measure various aspects of process performance and from the controls evolved signal the conditions leading to i n c i p i e n t weld defects and possible correct and compensate for these out of tolerance conditions without operator p a r t i c i p a t i o n BACKGROUND I t i s apparent from the preceding that the present adaptive controls are rather rudimentary The sensors each measure a phenomenon which has been found to give a q u a n t i t a t i v e i n d i c a t i o n of some aspect of the process performance The c o n t r o l l e r corrects the input to compensate for only some not a l l - of the manufacturing variables In each case the sensor precisely and with great s e n s i t i v i t y measures a parameter which can be observed by a trained operator or by appropriate instrumentation when the change becomes of s u f f i c i e n t magnitude The c o n t r o l l e r makes corrections con tlnuously without lag and without error These corrections could also be made by a trained operator but a greater departure from the desired performance would occur before he would perceive the change and make the correction and he would be l i k e l y to either under compensate of over-compensate The adaptive control systems presently available measure rather obvious phenomena which constitute an i n d i r e c t measure of process performance and act on one of the controlled input parameters to maintain an on l i n e performance standard These controls were developed rather quickly when the need became apparent and the equipment developers were conditioned to think i n terms of adaptive con t r o l Further developments i n t h i s area w i l l probably be more subtle i n nature and more d i f f i c u l t to a t t a i n APPROACH The f i r s t need is for sensors which can measure various aspects of process performance which w i l l signal i n c i p i e n t weld defects Two kinds of programs are envisioned Those directed toward improved understanding of the fundamental nature of the welding processes and those i n pursuit of promising ideas 1 I n e r t Gas Shielded E l e c t r i c Arc Welding 1 1 Porosity 1 1 1 One possible cause of porosity is turbulence i n the arc which may aspirate atmospheric a i r int o the i n e r t gas shield The electro magnetic r a d i a t i o n from the arc might give a q u a n t i t a t i v e measure of i t s state After a measure of arc s t a b i l i t y has been developed i t w i l l be necessary to determine which parameters should be adjusted to restore arc s t a b i l i t y 1 1 2 Spectrographic analysis of the arc might be u t i l i z e d to detect the hydrogen lev e l Since hydrogen appears to be the cause of porosity i n aluminum welds the l e v e l of hydrogen population in the arc plasma may give warning of conditions l i k e l y to r e s u l t i n porous welds Welding speed may be adjusted to the hydrogen concentration with appropriate adjustment to the dependent parameters D i f f i c u l t i e s include the need to d i s t i n g u i s h the cause of increased population and once the cause is recognized to automatically take corrective action Continued on next page
235 CHART , NO ¥33 APPROACH, c o n t i n u e d 1 I n e r t Gas S h i e l d E l e c t r i c Arc Welding, cont d 1 2 Lack o f Fusion and Weld Geometry Defects C a r e f u l o b s e r v a t i o n i n d i c a t e s t h a t v a r i a t i o n s i n arc geometry and i n the s i z e and shape of the m o l t e n puddle behind the arc occur d u r i n g the progress o f a weld These phenomena c o u l d p o s s i b l y be monitored u s i n g p h o t o e l e c t r i c techniques The next step would be t o determine the e f f e c t o f such v a r i a t i o n s and the process adjustments r e q u i r e d t o e s t a b l i s h an optimum cond i t i o n 2 E l e c t r o n Beam Welding T h i s process i s much l e s s s e n s i t i v e t o base m e t a l and heat s i n k v a r i a t i o n s than are the e l e c t r i c arc w e l d i n g processes I t does however r e q u i r e good c o n t r o l o f f i t up I t i s p o s s i b l e t h a t f i t up c o u l d be monitored by e l e c t r i c a l l y I s o l a t i n g the backup from the work piece and measuring the beam c u r r e n t c o l l e c t e d by the backup I t may a l s o be p o s s i b l e t o auto m a t i c a l l y Increase the power o u t p u t or p r o v i d e some t r a n s v e r s e o s c i l l a t i o n as the gap i n sensed Compensation f o r arc outs caused by momentary b u r s t s o f gas or vapor must be c o n t r o l l e d 3 Resistance Spot Welding There may be b e n e f i t from expanding the scope o f the expansion measurement and feed back device d e s c r i b e d p r e v i o u s l y For example the r a t e o f change i n expansion i s a measure o f the h e a t i n g r a t e p r i o r t o m e l t i n g and o f the c o o l i n g r a t e o f the weld I f a mathematical model of the optimum spot w e l d i n g c o n d i t i o n were c o n s t r u c t e d i t would be p o s s i b l e t o compare and c r e a t e c o i n c i d e n c e between a c t u a l expansion r a t e and magnitude and the model This would r e q u i r e t h a t the a d a p t i v e c o n t r o l a c t on the phase s h i f t c o n t r o l as w e l l as on w e l d i n g time I n a d d i t i o n i t may be p o s s i b l e t o i n i t i a t e the f o r g i n g f o r c e from the expansion feed back s i g n a l UNCONTROLLABLE INPUT VARIABLES SET POTl S CONTR OILED INPUT VARIABLES PROCESS MEASURABLE OUTPUT VARIABLES SENSORS ADAPTIVE CONTROLLER FIGURE OF MERIT CONSTRAINT VIOLATIONS PERFORMANCE MEASURING SYSTEM DESIRED PERFORHANCE CRITERfON EXTERNAL CONDITIONS FIGURE 4 GENERALIZED ADAPTIVE CONTROLLER
236 PRIORITY RATING WORKSHEET P R O G R A M P A C T D R S « PROflRAM P R O B A B I L I T Y OF S U C C E S S D l o w D MOoeRATE > t HlfiH CRITICAL PBOBtEMS TO BE SOLVED ⢠FEVV/NOT TOO P I F F U 7 U t T V S O M E / O l F F I C I I k T D M A N Y / VERY P I F F I C U t T PROCESS GROWTH POTENTIAL ⢠LITTLE Oft UNOCFINABLE X K e C M H R A B L E PoreMTIAL APPLICATIONS OraEB. TWAN AIR FORCE ⢠NONE ⢠SOME ft MANY NECESSITY FOR AIR FORCE FUNDINQ n LOW Hi«H wtasiav/oTHtft <So»r CFFoar 4. MootttATs - s m r EFRwr onuK ^euooes e a w e u i s i y E A I R foeet F U H P U K C L > I rz. z 5 8 2 9 6 O 4 O 4 e NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiQN P S O B A e i t - i r y n. FAIR. P R O B A S I L I T V 8 LOW P R O B A B I L I T Y 4 COMPONENT C R I T l C A L I T Y VERY HIiSH I t HIAH 9 F A I R 6 LOW 3 PRCauCNCV OF REQUIRE MENT IN « V « r e M MOM THAN 3 C«MPm<eHTS 3 2. 3 CeMPeMENTS 2 S I N G L E CeMPONENT I D E S I G N A L T E R N A T E S N o A L r e R N A T e r e a e e e e M 9 ONE ALTERNATE 6 S E V E R A L A L T E R N A T E S 3 M A T E R I A L S IMPLKSATION New MATERIAL Kve iOfUCNT SCA O 6 rwreRiAL iMPaovEMCNT e s a ' D 4 NO P R o e L E M F o R c s e e N o CALCULATE PRIORITY. S T E P I CIRCLE HIQHCST A A R P RAW S C O R E CHART e 8 e 33 RAW SCOUS F O R E A C H REFCCeiMP C D M P O N C N T IN TABLES AT e»ii> O F PAUei VSepocT WITH T!Atk> T O T A L S ENTERrP I N ^UMMDEV AT K » 6 U T S V S T C M S AARP seooes ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠C Z I C Z ] ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠C ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠C ⢠⢠⢠c u e ⢠⢠⢠n o S T E P a S T E P 3 IN EACH cn-HER S V 8 T C M IF WITHIN 4 P O I N T S NUMBER O F SVfTEMS H ldH C i R C t e NEXT H I O H C S T S C O R E OP T O P S C O R S n > 3 U W > » - C l R C t e F R E Q U E N C Y DISTRIBUTION F A C T O R M i M B e o . O P S f t r e M * rtu&M NUMaeR. OF S Y S T E M S LOW 1 0 1 2 1 4 1 1 1 3 1 4 1 z 1 *f 1 4 T O T A L B & L O W i PRIORITY
237 TITLE BONDING CERAMICS TO METALLIC STRUCTURES CHART N O y ^ / PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Bonding o f (1) g l a s s t o s u p e r a l l o y s / r e f r a c t o r y m e t a l s (2) r e f r a c t o r i e s t o s u p e r a l l o y s / r e f i a c t o r y metals A p p l i c a t i o n s are o p t i c a l and e l e c t r o m a g n e t i c t r a n s p a r e n c i e s j o i n e d to s t r u c t u r e s f o r use t o 2500F maximum t o g i v e vacuum t i g h t j o i n t f o r s i z e s up t o 2 f e e t heat s h i e l d s t o p r o t e c t antenna systems and ceramic s u b s t r u c t u r e t o support EM t r a n s p a r e n c i e s AARP REFERENCES E Chnrt. 24. B Chorti 12 , 25. 97. 275 13, 30e. 41e, 124. 125 P4FVPS Charts. APPLICABLE PROCESS FURNACE BRA^;iNG ADHESIVE BONDING Code 6 05 01 6 08 00 STATE OF THE ART ASSESSMENT Ceramic and g l a s s t o m e t a l j o i n t s are made r o u t i n e l y i n the vacuum tube i n d u s t r y but Lemperatures and s i z e s are not as advanced as r e q u i r e d f o r the attachment o f t r a n s p a r e n c i e s Ceramic radomes w i t h brazed metal attachments are made i n s i z e s exceeding 1 f o o t but do not have the temperature c a p a b i l i t y l e q i r e d Increase o f s e r v i c e temperature w i l l r e q u i r e h igher s t r e n g t h a l l o y s and must i n c l u d e the r e f r a c t o r y metals f o r use t o 2500 F A l t h o u g h c l o s e matched expansion m a t e r i a l s such as s t a b i l i z e d z i r c o n i a columbl m a l l o y s can be j o i n e d f o r use 11 vacuum environment the problem o f o x i d a t i o n p r o t e c t i o n of t h i s system has not been solved I n a d d i t i o n d e t e r i o r a t i o n o f metal ceramic c o m b i n a t i o i s over p e r i o d s up to 30 000 hours i s c o m p l e t e l y unknown Vacuum t i g h t n e s s i s achieved by m e l t i n g the adhesive (braze a l l o y or g l a s s based ceramic adhPEive) Equipment to p e r f o r m these j o i n i n g processes i s c u r r e n t l y a v a i l a b l e and presents no problems Tests of X 20 windows w i t h mechanical attachment were not s u c c e s s f u l above lOOOF because, o f excessive thermal s t r a i n s Large d i f f e r e n c e s i n mass between the t h i n Rene 41 s k i n s and the heavy s i l i c a window and attachment led to major d i f f e r e n c e s i n h e a t i n g r a t e and hence t c m p e i a t u r e T h i e x p e r i e n c e i n d i c a t e d t h a t m a t e r i a l s development must go hand i n hand i t h j o i n i n g process development CRITICAL PROBLEMS 1 Basic m a t e r i a l s development f o r EM p r o p e r t y o p t i m i z a t i o n 2 Design of t r a n s p a r e n c y t o achieve (a) Aerodynamic s u r f a c e s a t j o i n t (b) Expansion t o l e r a n c e a t j o i n t s between c e r a n i c and m e t a l l i c member Matching o f expansion co e f f i c i e n t s between metal and ceramic \ i l l not be adeq ate because more massive window and frame w i l l heat slower than s i p c r a l l o y or r e f r a c t o r y m e t a l s k i n s F l e x i b l e j o i n t members appear t o p r o v i d e th o n l y s o l u t i o n ( f o r example housekeeotr e j l or one of the many m o d i f i c a t i o n b o f t h i s ) Design w i l l be the most c r i t i c a l f a c t o r i n t h i s development Continue on next page ALTERNATE PROCESSES NOW Code
238 CHART , ^ . N O Â¥01 CR TICAL PROBLbMS. con t i n u e d 3 En\ Ironmental f a c t o r s (n) Thermal Thermal c y c l i n g i n m u l t i p l e f l i t , h t s i l l g enerate t h e r m a l t r a i n s and lead t o thermal f a t i g u e f a i l u r e s I f h aCing r a t e s are v e r y h i g h f a i l u r e may be by thermal shock i n f i r s t c y c l e ( b ) O x i d a t i o n r e s i s t a n c e ( c ) Gannoa and neu t r o n r a d i a t i o n ' Attachment o f metal frame t o s t r i c t re (a) O x i d a t i o n r e s i s t a n c e T h i s may r e q u i r e o x i d a t i o n p r o t e c t i o n c o a t i n g a f t e r making the j o i n t (b) P r e s e i v a t i o n o f design requirements (2) above ( c ) Uniform and adequate w t t l n g o f both ceramic an I n o t a l by f i l l e r The usual s o l u t i o n i s t o m e t a l l i n e the ceramic by s p r a y i n g or s i n t e r i n g w i t h c l o s e c o n t r o l o f atmosphere Another s o l u t i o n i s t o i n c o r p o r a t e a c t i v e m e t a l s ( T i Z r ) i n t o the bonding media I f a ceramic adhesive i s used the metal s u r f a c e may be o x i d i z e d p r i o r to (or d u r i n g ) bonding (d) Achievement o f va c i m q u a l i t y j o i n t s T h i s i s achieved most r e a d i l y by a molte n or p l a s t i c f i l l e r (braze a l l o y or g l a s s bond) Ceramic adheslves do not appear capable to p r o v i d e a s o l u t i o n t o t h i s problem area S o l u t i o n o f t h i s problem i s c r i t i c a l l y dependent on u n i f o r m w e t t i n g 5 Harmful i n t e r a c t i o n s between cerâmic braze s t r u c t u r e and p o s s i b l y t h e c o a t i n g i f p r e s e n t 6 A b i l i t y t o w i t h s t a n d low p r e s s i r e at h i g h temperature 7 High temperature s t r e n g t h o f 5000 p s i 8 Cost and r e l i a b i l i t y o f j o i n t s 9 I n s p e c t i o n o f j o i n t s PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To analyze the m a n i f o l d problems r e l a t e d t o the attachment o f t r a n s p a r e n c i e s t o v e h i c l e s t r u c t u r e s and from t h i s a n a l y s i s t o develop d e s i g n concepts and nethods which may be ev a l u a t e d and t o s e l e c t the optimum approaches f o r r e l i a b l e d e s i g n BACKGROUND D i f f e r e n c e s i n expansion c o e f f i c i e n t s and h e a t i n g r a t e s make the problems o f tran s p a r e n c y attachment acute F l e x i b i l i t y o f j o i n t s I s i m p e r a t i v e and t h i s need i n t r o d u c e s the problem o f d e v e l o p i n g bonding agents w i t h adequate s t r e n g t h s under these c o n d i t i o n s which a l s o meet the o t h e r parameters o f o x i d a t i o n r e s i s t a n c e h i g h temperatures and r a d i a t i o n APPROACH Phase I Systems A n a l y s i s Review p r i o r systems o r i e n t e d work on t r a n s p a r e n c i e s and i d e n t i f y I n s t a l l a t i o n problems and f a i l u r e modes Develop d e s i g n requirements f o r optimum systems and from these new de s i g n concepts aimed a t a v o i d i n g past problems V a r i o u s m a t e r i a l s and bonding agents s h a l l be s e l e c t e d f o r e v a l u a t i o n i n Phase I I Phase I I M a t e r i a l s & J o i n t Development Through specimen a n a l y s i s under the si m u l a t e d environments o f I n t e r e s t the p r o p e r t i e s and i n t e r a c t i o n o f v a r i o u s t r a n s p a r e n c i e s and bonding agents s h a l l be s t u d i e d Candidate j o i n t s s h a l l be s u b j e c t e d t o h i g h temperature c y c l i n g and f a t i g u e u s i n g v a r i o u s s t r u c t u r a l m a t e r i a l s The adheslves s h a l l be analyzed f o r c o r r o s i o n o x i d a t i o n and ot h e r h a r m f u l r e a c t i o n s Phase I I I P r o d u c t i o n and T e s t i n g Protoype hardware u s i n g one or more of the best systems e v o l v i n g i n Phase I I s h a l l be c o n s t r u c t e d and t e s t e d T e s t r e s u l t s s h a l l be compared w i t h p r e d i c t e d r e s u l t s from the d e s i g n a n a l y t i c a l and specimen t e s t i n g phases o f t h i s program From t h i s e f f o r t s u i t a b l e d e s i g n g u i d e l i n e s s h a l l be developed
239 PRIORITY RATING WORKSHEET CHART P R Q g R A M P A C T O R S . P R O f l R A M P R O B A B I L I T Y O F S U C C E S S ⢠LOW 2. % MOOERATC 5 ⢠HICH 8 C R I T I C A L P R O B L E M S TO B E S O L V E D n F t W / N O T TOO P I F F W U L T 2 ^ S O M E / D I F F I C U L T a M A N Y / V E R Y D I F F I C U L T S PROCeSS aROWTH ROreNTIAL X L I T T L E OR U N D E F I N A B L C O ⢠l ! e e 0 6 N R A B L E P O T E M T I A L 4 A P P L I C A T I O N S O T H E R T X A N AIR P O R C E ⢠NONE O TA S O M E 4 ⢠MAMY S NECESSITY FOR AIR FORCe FUNOINQ n LSW HlfiH INfltSTaV/cTHCA CFFo&r 4. n MeoesATi - S M e E F n t T orHOt 'Souooes « EXeUISiyE AlR F»ACk FUMP N« UKCL1 14. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIOH P B O B A e i L I T Y FAIR. P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y V E R Y HI<3H H I « H F A I R L o w F R E a u G N O y O F R E O U I R E M E N T IN S Y S T E M M « B e T H A N 3 C < > M P n < » H T 9 2 . 3 M M P » M E N r S S i N d L E C t P M P e N C M T D C S l f i N A L T E R M A T E S Ne> A L T e R N A T e R K I E s e e N ONE A L T E R N A T C S E V E R A L A L T E R M A T E C M A T E R I A L S I M P L I C A T I O N N e w MATEWflL P e v E U I ^ M e M T R C A O iMWTCRiAk i M P d o v e M t w T e £ a D N o P R e e u E M F o e e ^ c e i d 12 0 4 14 9 3 2 I 9 6 3 6 4 o CALCULATE PRIORITY- RAW S C o A E S r o R E A C H R E F C K E M O P CoMIWNCtfT M T A B U * A T EWD o r P A N E L tePe«T W I T H ViAtO T O T A L S ENTcacP M Q U M U A t V AT tZiauT S Y S T E M S S 3a A A R P RANM SCoOCS n i S T F P I C I R C L E M I Q H E S T A A R P R A W S C O R E S T E P a I N e A C M O T H E R S V 8 T 6 M C I R C L E N E X T H I S H C S T I F W I T H I N 4 P O I N T S O F T O P S C O R S n ' 5 2- S C O R E tOfW 2 6 ⢠⢠â¢â¢O ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠a ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠c z ⢠⢠⢠[ â¢cz]c: ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠S T E P 3 C l R C U e N U M B E R OF S y s T E l U S H I A H FReOUCMCY DISTRIBUTION F A C T O R f " BELOWi N U M B E R O F S Y S T E M S LOW NUMaeit. OP 1 « Y S T « M « 2. 3SSMMU 0 1 0 1 a 1 4 1 1 1 1 3 1 V Z RMOOE 1 z 1 0 4 ) T O T A L PRIORITY ( I )
240 TITLE AKffiSIVE BONDING OF CERAMICS TO REFRACTORY METALS CHART PRIORITY RELATED CAMR CHARTS _iZL MANUFACTURING REQUIREMENT Adhesive bonding of (1) Ceramic s l a b to r e f r a c t o r y metals (2) Ceramic I n s u l a t i o n to r e f r a c t o r y metals A p p l i c a t i o n s are ceramic t i l e and shingle attachments to e x t e r i o r surface of nose leading edge or aerodynamic su r f a c e s ceramic I n s u l a t i o n to r e f r a c t o r y metal s t r u c t u r e s for use a t 3000to 5000 F s e r v i c e temperatures AARP REFERENCES E Chart. 68 69 98 269 282 B Charts. 28c 29b 30d 39c Aid 121c 133b P4FVPS Charts. APPLICABLE PROCESS CERAMIC ADHESIVE (CEMENT) BONDING Code 6 08 OA STATE O F THE ART ASSESSMENT The ceramic m a t e r i a l s for nosecaps leading edges and s h i n g l e s have not been developed so Che s t a t e of the a r t cannot be f u l l y assessed However I t i s almost axiomatic that high temperature s t r u c t u r e s must be developed as a u n i t for example the m e t a l l i c s t r u c t u r e and ceramic I n s u l a t i o n for Solar s Asset nosecap were developed side by s i d e T h i s showed that problems of I n t e r a c t i o n oxidation p r o t e c t i o n expansion match emlttance c o n t r o l and so on could be solved to y i e l d a 3500 F s t r u c t u r e I t appears reasonable to assume that s p e c i a l m a t e r i a l s systems can be developed for s p e c i a l a p p l i c a t i o n s when the requirements can be stated Methods to minimize thermal s t r a i n s have been studied Including expansion gaps match of thermal expansion p l a s t i c flow compensating shrinkage by transformation i n the ceramic (ZrOj and HfOj) and combinations of these methods Ceramic adheslves to a t t a c h ceramic to ceramic or to metal can be developed r e a d i l y based on the technology accumulated In the course of the ceramic development Additions to reduce the f i r i n g temperature to lead to a ceramic adhesive are l o g i c a l e v o l u t i o n s from the work on the ceramic s t r u c t u r e Z i r c o n i a has been Joined to columblum a l l o y s and tantalum but the r e f r a c t o r y metals were not coated and hence are unsuitable for r e - e n t r y use CRITICAL PROBLEMS 1 M a t e r i a l s must be c l e a r l y defined Ceramic must be developed s p e c i f i c a l l y for an a p p l i c a t i o n to provide p r o p e r t i e s required by the design e g expansion match 2 D i f f e r e n t i a l expansion between ceramic and r e f r a c t o r y metal Matching expansion of the two components w i l l not be adequate because thermal t r a n s i e n t s and high heating r a t e s w i l l c r e a t e large temperature d i f f e r e n c e s 3 I n t e r a c t i o n between ceramic and r e f r a c t o r y metal and coating A High peel or normal s t r e s s e s on J o i n t s 5 T y p i c a l r e f r a c t o r y metal coatings are too weak to t r a n s f e r load e g weak b r i t t l e s i l l c l d e on surface of columblum 6 Inspection of J o i n t s ALTERNATE PROCESSES MECHANICAL FASTENERS MECHANICAL FASTENERS PLUS CERAMIC BONDING Code 6 11 0 6 11 0/6 08 OA
241 CHART , ^ NO jOS- PROPOSED DEVELOPMENT PROGRAM OBJECTIVE Development of hot s e c t i o n s of hypersonic v e h i c l e s must consider the t o t a l problem S p e c i f i c o b j e c t i v e s must be set i n terms of f l i g h t p r o f i l e s and sec t i o n s must be developed to meet these conditions Competing systems such as a b l a t i v e c o n s t r u c t i o n s must be analyzed so that weight performance heat flow through ceramic s t r u c t u r e re u s a b i l i t y c o s t and other targets can be set BACKGROUND T h i s type of system must be developed as an e n t i t y for p a r t i c u l a r s e r v i c e conditions so that a l l I n t e r a c t i n g f a c t o r s are considered Design coating ceramic i n t e r a c t i o n thermal expansion allowances strength of ceramic to s t r u c t u r e j o i n t s thermal shock r e s i s t a n c e and so on must be considered together For example expansion gaps between small hexagonal z l r c o n i a t i l e have been used I n one approach with weak porous cement i n the gaps to allow for expansion I n another approach the ceramic has been r e i n f o r c e d by metals from the platinum a l l o y group I n a t h i r d approach shrinkage at the phase transformation of p a r t i a l l y s t a b i l i z e d hafnia plus shrinkage from d e n s i f i c a t l o n has been used to maintain dimensional match with a 90 Ta lOW a l l o y substrate I n a fourth approach shrinkage of t h o r i a between 3200 and 4500 F has been used to maintain expansion match with tungsten mesh reinforcement and tungsten substructure The l a t t e r flew s u c c e s s f u l l y on the Asset g l i d e re-entry v e h i c l e and was recovered Cracking of the ceramic was to l e r a t e d on cool down because the gaps c l o s e up again on subsequent heating Attachment of t h i s ceramic to the tungsten substrate was by mechanical means I t I s evident from t h i s v a r i e t y of approaches that j o i n i n g cannot be considered s e p a r a t e l y from the o v e r a l l system f a b r i c a t i o n APPROACH Programs to develop s p e c i f i c nose-caps leading edges and aerodynamic surfaces are proposed These w i l l r e q u i r e preparation of p r e c i s e s p e c i f i c a t i o n s for each component based on s p e c i f i c aerospace v e h i c l e s An a l t e r n a t e approach w i l l be general s t u d i e s of nosecaps or leading edges s u i t a b l e for o r b i t a l (or s u p e r o r b i t a l ) r e - e n t r y f l i g h t Here the range of po s s i b l e conditions w i l l be considered and general s o l u t i o n s developed Close I n t e r p l a y between design and t e s t w i l l be e s s e n t i a l i n any program For t h i s reason the proposed program i s l i k e l y to be sponsored J o i n t l y by groups such as Manufacturing Technology D i v i s i o n and the F l i g h t Dynamics Laboratory
242 PRIORITY RATING WORKSHEET CHART , NO Â¥of PROGRAM PACTQRa. PROCESS P R 0 6 R A M P R O B A B I L I T Y O F S U C C E S S a L O W y i M O D E R A T E ⢠H I A H CRITICAL PROBLEMS TO B E SOLVED F C V V / N O T T O O D I F F I C U L T 3 0 M E / O I F F I C 0 L T a M A N Y / V E R Y D I F F I C U L T G R O W T H P O T E N T I A L ⢠L I T T L E O R U N O C F I N A B L E % R E M S H R A B L E P O T E N T I A L A P P L I C A T I O N S O T H E R T X A N A I R FORCE ⢠NONE S O M E M A N Y NECESSITY FOR AIR TORCC FUNU>INCI n l o w - HifiH w p a s r a v / ' o r H t a 6 « T CFFMT l^ a KiracSATC - S i t a e EFRKT o n u s ^oatets e E M U I S I I f E A M foue F U N P M « U K S L W H . 1 z a 8 2 9 S O ⢠o 4 e 30 NEED FACTOj^S SYSTEMS PRDBABIUTY H i a n P R o B A e i n T Y 12 F A I R P R O B A B I L I T Y % L O W P R O B A B I U T Y 4 C O M P O N E N T C R I T l C A L I T Y V E R Y H I < S H 12 H I « H 9 F A I R 6 L e w S F R E Q U E N C Y O F R E Q U I R E M E N T IN S Y S T E M M O U T H A N 3 C O M P O N E N T S 3 2 3 C O M P e M E N T S 2 S I N d L E C e M P O N E N T I O e S I S N A L T E R N A T E S N o A L T E R N A T E n a E S E E N ~ 9 OMC A L T E R M A T e « S E V E R A L A U T E R U A T E C 3 M A T E R I A L S I M P L I C A T I O N N e w M A T E R I A L I » v e t o F " t » l T e e « o 6 M A T C R I A L I M P a O V E M C N f e E S < D 4 NO p R o & L E M F e A e s c e N o CALCULATE PRIORITY. R A W S C O R E S F O R E A C r i REFfEENaP O O M F O N C N T M TABLES AT EMC o r P A N E L SepocT W I T H liAlO T O T A L S ENreOCP M « U M « A « V AT K I 6 M T S V s r e M S AARP RAVI seoses [lacszigginc i z ] [ i E i n a n ⢠⢠⢠⢠⢠S3i ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠C Z l ] ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠i n S T E P I CIRCLE MISHCST A A R P RAW S C O R E n e S T E P 2 IN EACH cn-HER S V 6 T S M C I R C L E NEXT H l f l M E S T IF WITHIN 4 P O I N T S OP T O P S C O R E " n ' NUMBER OF SytTEMS HlflA ^ L O W ^ 34 S C O R E S T E P 3 C I R C L E F R E Q U E N C Y DISTRIBUTION F A C T O R HUMBea. O K R V S r E M * H M N I Z 3 «B MMtC f " BELOWl N U M f i E R O F S V S T C M S t e w 0 I 2 OA Moat 1 0 1 a 1 4 1 1 1 3 <â¢:> 1 £ 1 4- 1 4 P = n « f = T O T A L - PRIORITY (D III
2A3 TITLE JOINING BRITTLE COMPOUNDS FOR HIGH TEMPERATURE USE CHART N O y / / PRIORITY J2L RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Many b r i t t l e m a t e r i a l s such as cermets oxides carbides borldes s l l l c l d e s and composite m a t e r i a l s must be Joined to themselves and to d i s s i m i l a r non-metallic m a t e r i a l s for s e r v i c e a t 2500 F and above Component s i z e s may be up to 6 fee t diameter and 15 feet long for propulsion a p p l i c a t i o n s H y personic-orbital a i r c r a f t ( h o r i z o n t a l take-off and landing) leading edges are much smaller 6 to 12 inches long with 1 5 Inch r a d i u s with a requirement for m u l t i p l e - f l i g h t c a p a b i l i t y and peak temperature to AOOO F AARP REFERENCES E Charts 118 51c. 52b B Chorts P&FVPS Chart. J o i n i n g No 2 APPLICABLE PROCESS NONE PREFERRED Code STATE OF THE ART ASSESSMENT Background information I n t h i s f i e l d I s Inadequate so that each problem as i t a r i s e s must be solved I n d i v i d u a l l y J o i n i n g of oxides I s most advanced S p e c i a l cements are a v a i l a b l e for many ceramics but g e n e r a l l y these require high temperature f i r i n g Strength and r e f r a c t o r i n e s s of these cements does not approach properties of ceramic The general problem of s t r u c t u r e s for use above 2500 F must be studied I n t e n s i v e l y because the rewards i n e f f i c i e n c y achieved with higher temperatures w i l l make such s t u d i e s w e l l worth while Refractory metal with coatings represents one approach to t h i s problem but r e l i a b i l i t y I S completely dependent on the r e l i a b i l i t y of the coating system Corrosion r e s i s t a n t ceramics such as oxides s l l l c l d e s and borldes represent another approach where the c r i t i c a l problem I s to prevent b r i t t l e f a i l u r e Few stu d i e s have been made I n t h i s area and of these perhaps the most s i g n i f i c a n t has been the e v a l u a t i o n of ZrB2-MoSl2 as a s t r u c t u r a l r e f r a c t o r y ceramic body Mechanical attachments were used and designed to minimize d i s r u p t i o n of thermal gradients yet many f a i l u r e s were as s o c i a t e d with J o i n t s The a p p l i c a t i o n of such m a t e r i a l s cannot be divided into compartments such as Joining but must consider a l l manufacturing operations at one time Manufacturing development e f f o r t should be d i r e c t e d toward f a b r i c a t i o n of prototype a r t i c l e s In advance of systems development schedules t o d i s c lose maj o r p r o b It-ms at the e a r l i e s t opportunity CRITICAL PROBLfMS 1 M a t e r i a l s must be c l e a r l y defined The term z i r c o n i a I s Inadequate to describe the oxide because small percentages of h a f n l a y t t r l a c a l c t a and other oxides are c r i t i c a l on s t r u c t u r e expansion emlttance and a l l other p r o p e r t i e s Some m a t e r i a l development may be required to accompany development of Joining techniques 2 Thermal expansion s t r e s s e s These are c r i t i c a l for d i s s i m i l a r m a t e r i a l J o i n t s but must a l s o be considered for s i m i l a r J o i n t s where high heating r a t e s may place J o i n t s In considerable s t r e s s p a r t i c u l a r l y i f the bond m a t e r i a l has d i f f e r e n t p r o p e r t i e s from the ceramic such as a lower thermal conductivity 3 High temperature f i r i n g R e f r a c t o r i n e s s i n the J o i n t g e n e r a l l y r e q u i r e s high temperature f i r i n g T h i s w i l l present a c r i t i c a l problem for the maximum s i z e s described A I n t e r a c t i o n The more m a t e r i a l s that are mixed i n a high temperature s t r u c t u r e the greater ^ Continued on next page ALTERNATE PROCESSES NONE Code
244 CHART CRITICAL PROBLgMS. continued the chance of i n t e r a c t i o n E u t e c t l c s between two m a t e r i a l s are the worst case but s o l i d s t a t e r e a c t i o n s may be eq u a l l y d e l e t e r i o u s 5 Impairment of p r o p e r t i e s of m a t e r i a l s Bond m a t e r i a l must not impair strength omittance surface condition or other s p e c i f i e d p r o p e r t i e s of m a t e r i a l 6 Design of J o i n t Because thermal expansion i s a c r i t i c a l problem J o i n t s must be designed to allow for t h i s Expansion J o i n t s must be provided i n s t r u c t u r e such as leading edge between hot ceramic m a t e r i a l s and cooler load bearing s t r u c t u r e PROPOSED DEVELOPMENT PROGRAM OBJECTIVE APPROACH Develop manufacturing techniques to assemble small ceramic type components into u s e f u l s t r u c t u r e s A p p l i c a t i o n w i l l be to aerospace s t r u c t u r e s for use above 2500 F A secondary o b j e c t i v e w i l l be to develop new manufacturing approaches that w i l l allow the designer new opportunities to construct with these m a t e r i a l s Because of t h i s c l o s e connection between design and processing work with such systems must be con ducted on a wide b a s i s with f r e e i n t e r a c t i o n between a l l d i s c i p l i n e s and processes A three phase program i s proposed to meet the o b j e c t i v e s stated above Phase I Analyze a l l probable aerospace a p p l i c a t i o n s of these ceramic-types m a t e r i a l s T h i s a n a l y s i s should include 1 Study of the requirement of components such as nosecaps leading edges nozzle guide vanes and ramjet I n l e t s 2 Study of the pr o p e r t i e s of e x i s t i n g m a t e r i a l s of t h i s type at the time t h i s work i s i n i t i a t e d Requirements of aerospace components must be studied completely and at the minimum w i l l include Temperature range Temperature t r a n s i e n t s Mechanical loading Corrosion and erosion conditions S p e c i a l environmental conditions such as ac o u s t i c noise l e v e l s Impact e t c S i z e Attachments required between i n d i v i d u a l components and between each Study of the pro p e r t i e s of m a t e r i a l s e x i s t i n g a t the time t h i s work i s i n i t i a t e d should not require major e f f o r t because of the e x i s t e n c e of groups such as Ceramics and Graphite Information Branch at RTD and work on a number of c o n t r a c t s to examine these m a t e r i a l s for nosecaps leading edges gas turbine and ramjet a p p l i c a t i o n s Phase I I S e l e c t examples where e x i s t i n g ceramics appear most l i k e l y to be s u c c e s s f u l and examine problems that must be solved Because J o i n i n g i s a key problem J o i n t design and Joining methods w i l l be given major a t t e n t i o n 1 J o i n t design Based on problems revealed by a n a l y t i c a l approach on Phase I develop J o i n t design to solve these problems T y p i c a l of the problems that w i l l r equire s o l u t i o n are a J o i n t designs to Increase load bearing c a p a b i l i t y by reducing s e c t i o n changes e t c b J o i n t designs to Increase thermal shock r e s i s t a n c e c J o i n t designs to allow for expansion (expansion J o i n t s ) Continued on next page
245 CHART PROPOSED CEVELOPMEOT PROGRAM, continued 2 J o i n i n g methods Study new Joi n i n g methods that w i l l o f f e r s o l u t i o n s to problems uncovered e a r l i e r These w i l l include s t u d i e s of cementing d i f f u s i o n bonding e l e c t r o n beam fu s i o n reinforcement J o i n t s molten ceramic brazing ( I n c l u d i n g exotherm brazing) and r e a c t i v e systems where J o i n t s are made at low temperature but have high temperature c a p a b i l i t y a f t e r r e a c t i o n Phase I I I Design and constr u c t components for t e s t to evaluate concepts Test to f a i l u r e I n simulated s e r v i c e conditions Analyze f a i l u r e s and make recommendations for developments required I n m a t e r i a l s design J o i n i n g and other areas
246 PRIORITY RATING WORKSHEET CHART P R Q C R A M F A C T O t t S P R 0 6 R A M P R O B A B I L I T Y O F S U C C E S S ⢠LOW Z yt. M O D E R A T E 5 ⢠H I b H 8 C R I T I C A L P R O B L E M S T O B E S O L V E D n F E W / N O T TOO P I F F U J U L T Z ⢠S O M E / D I F F I C U L T 5 H M A N Y / V E R Y O l f P I C U L T 8 P R O C E S S G R O W T H P O T E N T I A L ⢠L I T T L E OR U N D E F I N A B L E O ft R E e 0 6 N I Z . A B L E P O T E N T I A L 4 A P P L I C A T I O N S O T H E R T H A N A I R F O R C E Q NONE o J t S O M E 4 D M A N Y e N E C E S S I T Y F O R A I R F O R C E FUNDlUa n LOW HISM |(H«ST(lV/orH£« <30VT CFFOftT 4 ⢠iMooeAATs - E F R x r OTHCK ^ e u o o e s S "Jt E X C U I S i y C AlR F»A£k F U M P M A U K C L V tZ. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIQH P R O B A B I L I T Y F A I R P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y V E R Y H I t H HI6H F A I R L e w F R E a U B N C Y O F R E O U I R E M E N T IN S Y S T E M MORE THAN 3 C O M P a N t H T S Z 3 C O M P O N E N T S S I N G L E CetAPONtHT D E S I G N A L T E R M A T E S No A L T E R N A T E ( t o a e s E E N ONE A L T E R N A T E S E V E - R A L A L T E R N A T e C M A T E R I A L S I M P L I C A T I O N N e w M A T E e . l A L P e V E l O P M E N T et» O MATERIAL I M P f t O V E M C N T E f A P NO P R O B L E M FoEtseeN I Z B 4 I Z 9 e> 3 3 2 9 6 3 6 4 o /Z J3 RAW s c o < t e s FOR E A C H R£FEEeMrcP CoMP0NCtfT M T A B L E S A T t N B o r PANEL RtPOtT lUITH 12AW T O T A L S E N T E O C P M SUMUntV AT eisuT 8 ^o- AARP RA^i scones _ 5 Z ] a a a ^[*2 ] D I 8Uf»)\S^\ II II II I 6 [ laiiDniziii iD ⢠⢠⢠⢠⢠⢠⢠⢠( ! ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠o n ⢠⢠n n i â¢â¢(mac ] ⢠⢠⢠⢠] ⢠⢠⢠⢠] ⢠⢠⢠⢠] ⢠⢠⢠⢠S T E P I S T E P 2 i l l 3Z CALCULATE PRIORITY- CIRCLE HIGHEST A A R P RAW S C O R E IN eACH OTHER S Y S T E M C I R C L E NEXT H I Q M E S T S C O R E IF WITHIN 4 P O I N T S o r T O P S C O R E n - Z â COW 2 S T E P 3 N U M B E R OF S Y S T C I f S HIAH C I R C L E F R E O U E N C Y DISTRIBUTION F A C T O R f " BELOWi NUMaen. O P S Y S T C M « I 2. N U M B E R O F S Y S T E M S LOW 2 I t M M E 1 0 1 Z. 1 4 1 1 1 3 1 4 1 2 . 1 4 p = T O T A L - 33 P R I O R I T Y m
247 TITLE FUSION WELDING LARGE GAUGE MATERIALS STRUCTURE OF THIN CHART PRIORITY RELATED CAMR CHARTS i ^ y L lot MANUFACTURING REQUIREMENT F u s i o n w e l d i n g i s r e q u i r e d t o j o i n t h i n gauge d e t a i l p a r t s i n t o l a r g e s t r u c t u r e s 1 B u t t weld t h i n sheets r a n g i n g from 0 005 t o 0 060 Inches i n aluminum a l l o y s t i t a n i u m a l l o y s p r e c e l p l t a t i o n s t r e n g t h e n e d n i c k e l base s u p e r a l l o y s a u s t e n l t l c s t a i n l e s s s t e e l maraglng s t a i n l e s s s t e e l f o r aerodynamic l i f t and c o n t r o l s t r u c t u r e s t h r u s t s t r u c t u r e bulkheads i n t e r stage and i n t e r tank s t r u c t u r e s heat s h i e l d s and pressure v e s s e l s 2 J o i n edge members t o l a r g e sandwich s t r u c t u r e s o f t i t a n i u m a l l o y s Facing gauges range from 0 005 t o 0 060 i n c h sandwich panels up t o 12 f e e t square and contoured 3 T welds j o i n i n g c o r r u g a t e d web 0 006 i n c h t h i c k minimum t o cap 0 010 i n c h minimum i n aluminum and alpha t i t a n i u m a l l o y s t o produce s t i f f e n i n g beams 4 S t r u c t u r e s i z e i s i n the order o f 50 f e e t + 1 i n c h long by 60 f e e t + 0 16 in c h diameter c y l i n d e r s and 40 f e e t + 0 50 i n c h t o r o i d a l tanks AARP REFERENCES E C h a r t s . B Char ts . 112 163 165 173 183 186 194 49 92 95b 96 97a b 98a b c 99 PSFVPS C h a r t s . APPLICABLE PROCESS One or more o f the f o l l o w i n g depending on end i t e m WELDING ELECTRON BEAM LASER PLASMA ARC or TIG (GTA) WELDING 6 01 12 Ì ?''?)1 15 6 01 11 6 01 01 STATE-OF THE ART ASSESSMENT Welding and post weld heat t r e a t m e n t problems are i d e n t i f i e d w i t h the p r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base a l l o y s The major d i f f i c u l t i e s p r e s e n t l y encountered are micro f i s s u r i n g d u r i n g w e l d i n g and s t r a i n age c r a c k i n g or heat t r e a t m e n t Welding problems are mi n i m i z e d by s u i t a b l e c o n t r o l over t h e p r i o r h i s t o r y o f the m a t e r i a l f o r example l i m i t i n g pre weld a n n e a l i n g temperature t o prevent g r a i n growth and u n d e s i r a b l e s o l u t i o n i n g o f compounds I n postweld heat t r e a t m e n t t h e r m a l g r a d i e n t s should be minimized c o n s i s t e n t w i t h maximum h e a t i n g r a t e s t h r o u g h the ag i n g range Residual s t r e s s e s should be kept as low as p o s s i b l e by w e l d i n g i n the s o f t c o n d i t i o n p r o v i d i n g proper j o i n t f i t up and u t i l i z i n g minimum energy i n p u t A s u b s t a n t i a l q u a n t i t y o f re s e a r c h i s p r e s e n t l y being conducted r e l a t i n g t o t h i s group o f a l l o y s and i t I s a n t i c i p a t e d t h a t p r e s e n t problems w i l l be s a t i s f a c t o r i l y r e s o l v e d d u r i n g the next f i v e years However i t w i l l p r o b a b l y be necessary t o weld these v e r y l a r g e t h i n w a l l e d s t r u c t u r e s i n t h e aged c o n d i t i o n The r e d u c t i o n o f d u c t i l i t y i n t h e 1200F t o 1600 F temperature range which i s c h a r a c t e r i s t i c o f the n i c k e l s u p e r a l l o y s a t pres e n t w i l l then become a s e r i o u s problem e s p e c i a l l y i n r e s t r a i n e d j o i n t s Two hypotheses have been proposed t o e x p l a i n t h i s phenomenon e m b r i t t l i n g e f f e c t s o f t r a c e i m p u r i t i e s and the f a c t t h a t the f l o w s t r e s s o f the N13AR s t r e n g t h e n i n g p r e c i p i t a t e reaches a maximum a t 1400F A l l o y Improvement i s r e q u i r e d t o improve w e l d a b l l i t y i n the aged c o n d i t i o n and t o Improve j o i n t e f f i c i e n c y i n the as welded c o n d i t i o n A low energy i n p u t w e l d i n g process w i l l be necessary A weldable beta t i t a n i u m a l l o y e x h i b i t i n g good f r a c t u r e toughness as welded must be developed The maraglng s t e e l i s a p p a r e n t l y s u f f i c i e n t l y tough f o r s t r u c t u r a l a p p l i c a t i o n s from 75F t o 320F but not acc e p t a b l e f o r use a t -423F The reason must be i d e n t i f i e d and the s t e e l improved i f i t i s t o be u t i l i z e d a t t h i s temperature A c c u r a t e l y f o r m i n g compound c o n t o u r s i n l a r g e t h i n gauge sheets and forming c o r r u g a t e d s t l f f e n e r s and s t r i n g e r s t o p r o v i d e the f i t up r e q u i r e d f o r w e l d i n g l a r g e t h i n gauge s t r u c t u r a l d e t a i l s w i l l be a s e r i o u s problem T o o l i n g w i l l be ext r e m e l y expensive and new concepts t o reduce t o o l i n g c o s t s are r e q u i r e d Problems a s s o c i a t e d w i t h b u c k l i n g t h i n gauge work hardened sheets due t o w e l d i n g heat induced s t r a i n r e l a x a t i o n w i l l c o m p l i c a t e the t o o l i n g problem Vacuum clamping u t i l i z i n g poor t h e r m a l c o n d u c t i v i t y back up and clamping members should be ALTERNATE PROCESSES NONE Continued on next £age Code
248 CHART STATE OF THE ART ASSESSMENT, co n t i n u e d c o n s i d e r e d s i n c e v a r i a t i o n s I n c o n t a c t area w i l l n o t cause v a r i a t i o n s I n s e n s i b l e heat s i n k which would a f f e c t weld c o n s i s t e n c y Castable n o n - m e t a l l l c m a t e r i a l s should be i n v e s t i g a t e d f o r back up and clamping members Methods o f j o i n t p r e p a r a t i o n w i l l r e q u i r e development I t w i l l be necessary t o c u t s l i t or machine the edge o f a sheet as t h i n as 0 005 Inches s u f f i c i e n t l y s t r a i g h t and w i t h adequate s u r f a c e f i n i s h t o b u t t up w i t h the a d j a c e n t sheet such t h a t the maximum gap does not exceed 0 0005 inches Some a l l e v i a t i o n i n the f i t up problem can be a t t a i n e d by l a y i n g a narrow s t r i p o f f o i l over the j o i n t and w e l d i n g through the f o i l by the e l e c t r o n beam or p o s s i b l y the l a s e r A l t e r n a t i v e l y f i l l e r w i r e can be used bur t h i s i s v e r y d i f f i c u l t c o n s i d e r i n g the gauge t h i c k n e s s T u r n i n g up r i g h t angle f l a n g e s about 2T i n h e i g h t s and b u r n i n g them down by TIG (GTA) w e l d i n g has been used s u c c e s s f u l l y T h i s w i l l r e s u l t i n h i g h e r energy i n put and g r e a t e r d i s t o r t i o n and I s not m e c h a n i c a l l y f e a s i b l e f o r many of the J o i n t c o n f i g u r a t i o n s i n v o l v e d The magnitude o f t h i s problem i s e x e m p l i f i e d by the p o s s i b l e r e q u i r e m e n t f o r a s t r u c t u r e o f 25 f e e t depth and 60 f e e t span o f chem m i l l e d s t i f f e n e d s k i n o f a t h i c k n e s s i n the range 0 006 through 0 060 i n c h For the l a t t e r fcauge u s i n g a h i g h energy w e l d i n g source f i t up must be w i t h i n 0 006 in c h The J o i n t p r e p a r a t i o n f o r the b u t t welds w i l l be a f o r m i d a b l e t a s k I n a d d i t i o n the need e x i s t s f o r f i n a l d i m e n s i o n i n g and J o i n t p r e p a r a t i o n p r i o r t o the l a s t c l o s e o u t welds P o r t a b l e s l i t t i n g or machining equipment must be developed T h i s i s i l l u s t r a t e d by the f i t t i n g o f the f i n a l gore segment p r e p a r a t o r y t o w e l d i n g f o r the e l l i p s o i d bulkhead o f 20 f o o t major diameter and 0 005 t o 0 060 i n c h t h i c k t i t a n i u m a l l o y The e x t e n t t o which the s t a t e o f the a r t w i l l e volve t o meet these needs w i l l depend upon the na t u r e o f the hardware c o n t r a c t s d u r i n g the next decade For many o f these a p p l i c a t i o n s a b s o l u t e l y minimum energy i n p u t d u r i n g w e l d i n g i s e s s e n t i a l Shrinkage and d i s t o r t i o n can d e s t r o y j o i n t f i t up D i s t o r t i o n can cause severe d i s c o n t i n u i t y s t r e s s e s a t J u n c t i o n o f mating assemblies E l e c t r o n beam w e l d i n g I s the p r e s e n t l y a v a i l a b l e process o f g r e a t e s t m e r i t f o r the m a j o r i t y o f these a p p l i c a t i o n s from energy i n p u t and weld q u a l i t y c o n s i d e r a t i o n s The s i z e o f the vacuum chamber r e q u i r e d i s a s e r i o u s economic handicap I t i s e s s e n t i a l t h e r e f o r e t h a t the l o c a l p o r t a b l e vacuum chamber welder now under development be s u c c e s s f u l l y implemented The evacuated back up o f t h i s concept would serve as the back up t o o l and p r o v i d e vacuum clamping as w e l l The v e r y l i g h t gauge t h i c k n e s s e s i n v o l v e d i n these s t r u c t u r e s are w i t h i n the p o t e n t i a l w e l d i n g c a p a c i t y o f a p o w e r f u l ruby l a s e r The l a s e r beam i s p o t e n t i a l l y a second energy sou ce f o r w e l d i n g t h m gauges w i t h minimum energy i n p u t The l a s e r i s an apparatus i n which an ensemble o f e x c i t e d atoms are caused t o emi t i n unis o n Since the r e s u l t a n t r a d i a t i o n may a l l be d i r e c t e d i n t o a s i n g l e beam and c o n c e n t r a t e d CO a v e r y h i g h i n t e n s i t y the l a s e r appears capable of p r o v i d i n g our tec h n o l o g y w i t h a second h i g h power d e n s i t y w e l d i n g t o o l Whereas the E l e c t r o n Beam r e q u i r e s a vacuum environment by i t s v e r y n a t u r e the Laser i s capable o f w e l d i n g I n w i t h o n l y a s u i t a b l e l o c a l i n e r t gas s h i u l d to a v o i d o x i d a t i o n M a t e r i a l s f o r w h i c h the b e n e f i t s o f the vacuum environment are un i m p o r t a n t such as aluminum and s t a i n l e s s s t e e l may be welded w i t h the advantages i n h e r e n t i n narrow deep p e n e t r a t i n g welds w i t h o u t the need f o r the vacuum chamber A major l i m i t a t i o n i s the low average power l e v e l t h a t can be a t t a i n e d w i t h p r e s e n t l a s e r s The ruby l a s e r i s perhaps the most p o w e r f u l o f the p r e s e n t l y a v a i l a b l e l a s e r s The c r y s t a l i s hard and rugged and has r e l a t i v e l y h i g h thermal c o n d u c t i v i t y I t e m i t s a t a wave l e n g t h o f 693 microns Neodymium doped barium crown g l a s s has a l s o been used f o r h i g h power a p p l i c a t i o n s I t has a lower t h r e s h o l d f o r o s c i l l a t i o n than t h a t o f the ruby and a h i g h e r c o n v e r s i o n e f f i c i e n c y On the o t h e r hand i t emits a t 1 06 microns where the r e f l e c t i v i t y o f metals tends t o be h i g h e r and i t has lower c o n d u c t i v i t y Thermal c o n d u c t i v i t y o f the c r y s t a l i s I m p o r t a n t because i t develops heat as a r e s u l t o f I t s i n t e r a c t i o n w i t h the pumping l i g h t The power o u t p u t o f the l a s e r beam decreases w i t h i n c r e a s i n g temperature T h e r e f o r e adequate c o o l i n g I s r e q u i r e d I n a d d i t i o n the pumping lamp must a l s o be cooled The d i f f i c u l t i e s i n d i s s i p a t i n g the heat generated i n the c r y s t a l and i n the lamp w i t h o u t Continued on next page
249 CHART c o n t i n u e d exceeding t h e i r l i m i t i n g temperatures Impose a r e s t r i c t i o n on the r e p e t i t i o n r a t e a t which the l a s e r can be pulsed Outputs i n the order of s e v e r a l hundred Joules have been observed w i t h pulse d u r a t i o n i n the order o f a few m i l l i s e c o n d s A r e p e t i t i o n r a t e o f about one pul s e every t e n seconds a t t h i s power l e v e l may be o b t a i n e d However a reasonable o p e r a t i n g c o n d i t i o n appears t o be i n the order o f one 10 Joule pulse per second Th i s i s e q u i v a l e n t t o a con t i n u o u s power o f 10 w a t t s The p r e s e n t l y a v a i l a b l e power and energy l e v e l s o f the l a s e r h a v i n g been e s t a b l i s h e d i t i s now p o s s i b l e t o examine i t s a p p l i c a b i l i t y t o w e l d i n g At f i r s t approach the l a s e r appears i d e a l l y s u i t e d f o r p r o d u c i n g welds o f d i s c r e t e and l i m i t e d area ( s p o t welds such as J o i n i n g m i c r o c i r c u i t r y l e a d s ) The p o s s i b i l i t y o f pr o d u c i n g c o n t i n u o u s b u t t welds by means o f a s e r i e s o f overlapped spot welds may a l s o be examined Haynes A l l o y 25 0 015 I n c h t h i c k was e l e c t r o n beam welded a t 19 KV 8 x 10 3 amperes and 64 inches p e r minute f o r a t o t a l energy i n p u t o f 0 14 k i l o j o u l e s per i n c h The t o t a l power was 152 w a t t s I f the r e f l e c t i v i t y o f t h i s m a t e r i a l i s s u f f i c i e n t l y low the ruby laser w i l l be j u s t capable o f w e l d i n g t h i s t h i c k n e s s The w e l d i n g speed however w i l l be reduced t o l e s s t h a n 0 1 inches per minute I t w i l l a l s o be necessary t o space the o v e r l a p spot welds w i t h p r e c i s i o n i n o rder t o I n s u r e pressure t i g h t n e s s and J o i n t s t r e n g t h The l a s e r beam can be t r a n s m i t t e d through the atmosphere w i t h o u t s i g n i f i c a n t a t t e n u a t i o n and i t can be p r o j e c t e d long d i s t a n c e s as can the e l e c t r o n beam On the other hand the f o c u s i n g l e n s r e q u i r e d t o a t t a i n the r e q u i r e d power d e n s i t y w i l l i n t r o d u c e a s e r i o u s problem The mechanism by which the narrow deep weld i s produced appears t o r e q u i r e the v a p o r i z a t i o n o f a s m a l l q u a n t i t y o f the base m e t a l The len s t h e r e f o r e w i l l q u i c k l y become coated from the metal vapor and w i l l be unable t o t r a n s m i t the beam energy The hazards o f r e f l e c t e d r a d i a t i o n p a r t i c u l a r l y t o the eyes of Che welder can be overcome w i t h s u f f i c i e n t care A l t h o u g h i t appears t h a t t h e pulsed c r y s t a l l a s e r w i l l have l i c c l e a p p l i c a C i o n t o s t r u c t u r a l w e l d i n g the long sought CW l a s e r i s now i n e x i s t e n c e CO2 l a s e r s e m i t a c o n t i n u o u s beam a t a wave l e n g t h o f 10 6 microns (where r e f l e c t i v i t y o f meta l s I s v e r y h i g h ) A s i n g l e tube s i x t o e i g h t f e e t I n l e n g t h can produce 75 t o 100 w a t t s I t would be f e a s i b l e t o u t i l i z e a m u l t i p l i c i t y o f such tubes t o produce an o u t p u t o f as much as 1 KW T h i s would be s u f f i c i e n t power t o weld about 0 060 i n c h t h i c k n i c k e l base s u p e r a l l o y i f the energy exchange were e f f i c i e n t However r e f l e c t i v i t y a t t h i s wave l e n g t h w i l l reduce the t h i c k n e s s c a p a c i t y p r o b a b l y t o l e s s than h a l f I n a d d i t i o n such a welder would be e x t r e m e l y b u l k y The s o l i d s t a t e CW l a s e r now under a c t i v e development I s much more p r o m i s i n g A l t h o u g h I t s power c o n v e r s i o n e f f i c i e n c y I s less than Chat of Che CO2 d e v i c e i c emi t s aC 1 06 microns AC t h i s wave l e n g t h the r e f l e c t i v i t y o f I n c o n e l X I s about 40 p e r c e n t o f alpha CiCanium a l l o y s i n excess o f 50 p e r c e n t The s o l i d staCe device i s more c o m p l i c a t e d t h a n the CO2 l a s e r but s m a l l e r i n s i z e f o r the same power o u t p u t AC Che presenc race o f developmenC i t i s p o s s i b l e t h a t s o l i d staCe CW l a s e r s w i l l be capable o f w e l d i n g 0 030 i n c h Chick s u p e r a l l o y i n f i v e years The C h l r d process o f m e r i t from t h e energy i n p u t sCandpoint i s the plasma a r c For t h e case o f w e l d i n g 0 015 i n c h c h i c k n i c k e l base s u p e r a l l o y Che energy Inpuc f o r Che elecCron beam was seen t o be 0 14 k i l o j o u l e s per i n c h For the plasma needle arc i t was found t o be 1 3 k i l o j o u l e s per i n c h a p p r o x i m a t e l y t e n times h i g h e r I f 25 percent o f the arc energy I s l o s t by r a d i a t i o n and conduccion Chls I s reduced Co 7 5 Clmes h i g h e r Chan elecCron beam NeverCheless Chls process w i l l be adequaCe f o r many a p p l l c a C i o n s The f o u r c h process TIG (GTA) w e l d i n g w i l l e x h i b i c much h i g h e r energy inpuC NeverCheless Chls process w i l l be used p a r d c u l a r l y f o r subassemblies where pose weld r o l l p l a n i s h i n g can be u d l l z e d I t I s Che besC s e l e c c l o n f o r Che T w e l d i n g o f Che corrugaCed web beams where massive Co o l i n g i s an InherenC requlremenc Concinued on nexc page
250 CHART N O *tt9 CRITICAL PROBLEMS 1 The n i c k e l base s u p e r a l l o y s r e q u i r e improvement t o meet these o b j e c t i v e s A weldable c t 1 c i t a r i im a l l o y x h i b i t i n g good as-welded f r a c t u r e toughness must be developed 2 New t o o l i n t concepts are necessary 3 Methods of j o i n t p r e p a r a t i o n r e q u i r e development PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To r e s o l v e the problems of j o i n t p r e p a r a t i o n and f i t up i n v o l v e d i n the f u s i o n w e l d i n g o f l a r g e t h i n gauge f u s i o n welded s t r u c t u r e s BACKGROUND S p e c i a l i z e d t o o l i n g and equipment are not a v a i l a b l e f o r s t i u c t u r e s o f the type d e s c r i b e d by AARP i n the v a r i o u s r e f e r e n c e s T h i s r e s u l t s i n expensive t o o l i n g c o s t s f o r each major program and e x t e n s i v e c u t and t r y mefhods t o e l i m i n a t e b u c k l i n g and f a u l t y welds due t o poor edge p r e p a r a t i o n and f i t New concepts are needed which can be a p p l i e d t o systems development programs APPROACH Phase I I n i t i a t e a study o f e x i s and problems encountered i n f a b r i c s gauge meta l s Examine advanced des advantageous over a l t e r n a t e t e c h n i q s e c t i o n s I d e n t i f y t y p i c a l m a t e r i a p r o p e r t y g o a l s and i n d i c a t e where e x i s t i n g t o o l i n g and j o i n t p r e p a r a t processes Devise new concepts app be t e s t e d e x p e r i m e n t a l l y t i n t t o o l i n g and j o i n t p r e p a r a t i o n t e c h n i q u e s i t i n g l a r g e s t r u c t u r e s by f u s i o n w e l d i n g t h i n i g n concepts t o v e r i f y t h a t f u s i o n w e l d i n g i s ues such as r e s i s t a n c e w e l d i n g o f overlapped l i s and weld j o i n t c o n f i g u r a t i o n s s i z e s and problems would be expected from use o f i o n techniques f o r the v a r i o u s f u s i o n w e l d i n g l i c a b l e t o r e p r e s e n t a t i v e problems which can Phase I I Design and c o n s t r u c t a p p r o p r i a t e scale models i l l u s t r a t i n g s a l i e n t p o i n t s o f the new approaches Determine the e f f e c t o f v a r i o u s w e l d i n g systems (energy i n p u t s ) on the end product E s t a b l i s h t r a d e o f f c o s t s f o r c o m p e t i t i v e s o l u t i o n s and show t h e i r a p p l i c a b i l i t y f o r v a r i o u s d e s i g n concepts o f advanced systems and components
251 PRIORITY RATING WORKSHEET CHART PRQgRAM PACTORfi: PROflRAM PROBABIL ITY OF S U C C E S S ⢠L O W a y( M O D E R A T E 5 ⢠HIQH 8 CRIT ICAL P R O B L E M S TO B E SOLVED Q F6^^/NOT TOO DIFFU;ULT 2 X S O M E / D I F F I C U L T S a M A N Y / VERY DIFFICULT 6 P R O C E S S G R O W T H P O T E N T I A L ⢠LITTLE OR UNDE F I N A B L E O X aU06Hn*»l.e POTEMTIAL 4 APPLICATIONS OTHER. THAN AIR FORCE ⢠NONE O X SOME 4 D MANY e N E C E S S I T Y FOR AIR FORCe FUNOIMO n L O W HI6H mtasTcv/'cTHCA 6<w- C F F o c r 4 X MoocttAiv - ScMC E F R « . r entte. S M M E S S ⢠E X C U l S l f E A l l foibCk. F U M P u a U K C L 4 n. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HICIH P S O B A B I L I T Y FAIR PROS A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T l C A L I T Y VERY HI<SH H I « H FAlA L o w F R E a U G N C Y OF R E a U I R E M E N T IN S Y S T E M Meat THAN 3 C«MP«NeHT9 Z 3 COMPONENTS S l N f i L E OOMPONENT DEStSN A L T E R W A T E S No ALTERNATe f S s E s e E N ONE ALTERNAre S E V E R A L A L T E R M A r e S M A T E R I A L S IMPLICATION New MATERIAL Peveu)(>MeMT RCA O MATCClAL IMPOAVEMCMT R f f i V NO P R e S L E M F o R C S C e N n. s 4 14 9 6 3 3 2 s 2C RAW SCORES FOR EACH REFfReMAP CoMIVNeNT M T A B U * AT END OF PANEL WITH 13AM TOTALS ENTEOrP M /w S Y S T E M S AARP RA>N seoaes A3a_ [ « ] ⢠⢠⢠[ HE ⢠⢠⢠⢠C ] ⢠] ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠I i n ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠] ⢠⢠⢠\njc3 CALCULATE PRIORITY. STEP I CIRCLE MIQHEST AARP UMi SCORE n a STEP 2 IN EACM OTHER SV6T6M CIRCLE NEXT HIOUEST SCORE 4tt STEP 3 IF WITHIN 4 POINTS NUMBER OF SYSTEMS HtdH CIRCLE OP TOP SCORE / tow i- FREOUENCY DtSTRIBUnON FACTOR MiMBeit . ot> s y s r C M * ttuari BELOWi I NUM&ER, OF S Y S T E M S t e w 0 I 2 H M O M 1 0 1 z » 4 1 1 1 3 1 <f d o 1 4 1 4 TOTAL PRIORITY
252 TITl£ BRAZING REFRACTORY ALLOYS METAL TO METAL AND HONEYCOMB CORE CHART NO PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Join various r e f r a c t o r y metal assembly d e t a i l s by brazing for service at temperatures through 3000 F Brazed assembly must withstand subsequent app l i c a t i o n of oxidation protective coating Materials Columbium (Cb melting point AA80F) molybdenum (Mo-A730 F) tantalum (Ta 5A20 F) and tungsten (W 6100 F) Applications include thrust deflectors nose cones leading edges skin panels ducts and honeycomb panels for airframe requirements Ftopulslon components require resistance to l i q u i d a l k a l i metals to 2000 F AARP REFERENCES E Charts LL t>5. 61, 91 B C h a r t s . 28c d 29b c d 30a 32a Ala 50a 51b 174 PSFVPS Char ts . Joining No 9 10 11 APPLICABLE PROCESS BRAZING by one of the following depending on end item (1) ELECTRIC BLANKET (2) FURNACE BRAZING (VACUUM AND RETORT) (3) RESISTANCE HEATING OF CERAMIC TOOLS (4) RADIANT LAMP HEATING Code 6 05 11 6 05 01 6 05 04 6 05 03 STATE O F THE ART ASSESSMENT Considerable a l l o y development and t e s t i n g e f f o r t s have been conducted over the past 10 years These e f f o r t s have resulted i n a large number of commercial and semi commercial alloys Some of the most popular materials based on consideration of a v a i l a b i l i t y mechanical properties cost r e l i a b i l i t y and consistency of product and f a b r l c a b i l i t y are as follows and are t y p i c a l candidates for future s t r u c t u r a l studies Columbium B 66 CB 752 FS85 Tantalum T 111 T 222 T 333 Hf Ta Tungsten Commercially Pure W 267 Re Development Analysis Development e f f o r t s aimed at using the re f r a c t o r y metals In brazed structures have been underway since 1957 The e f f o r t s have been in three d i s t i n c t areas (1) brazing a l l o y develop ment (2) brazing process development (3) coating development Given an a l l o y system that is metallurgic consideration in a l l o y development Is the flow metallurgy of the base metal Heating at certa to experience a considerable loss of d u c t i l i t y and cooling processes whose flow temperatures a obtain any measure of useful strength at temper considerably above th e i r flow temperatures are w i l l be required to operate at service temperat permissible flow temperature can be Increased keep these temperatures as low as possible i n c d i f f i c u l t i e s a l l y compatible w i t h the base metal the prime temperature This is dictated by the physical i n high temperatures causes the ref r a c t o r y metals I t Is therefore desirable to use brazing alloys re near or below these levels Therefore to ature a l l o y systems which show remelt temperatures necessary Certain r e f r a c t o r y metal structures ures above r e c r y s t a l l i z a t i o n In these cases the However i t is s t i l l of paramount Importance to onslderatlon of processing and equipment Continued on next page ALTERNATE PROCESSES NONE Code
253 CHART STATE OF THE-ART ASSESSMgWT. continued Exemplary a l l o y compositions Include Braze alloys for columblum and molybdenum (1) Tl-Cr-Zr (2) Ti-Cr-Sn (3) Tl-Cr-Pd (4) T l Pd-Sl (5) Tl-Cr Be (6) Ti-V-Cr-Al Braze alloys for tantalum (1) Cr-Tl-Pd-Mn (2) Ti-Cr-Pd (3) Tl-Cr-Be Braze a l l o y for tungsten (1) Mo-V B Three brazing processes have shown production f e a s i b i l i t y These Include E l e c t r i c Blanket Vacuum Radiant Furnace and Quartz Lamps From the standpoint of minimum loss of base metal mechanical properties and cost processes which minimize the time at braze temperature hold a d i s t i n c t advantage Specific R&D programs have been Government sponsored on both vacuum radiant and the quartz lamp processes E l e c t r i c blanket concepts which also have advantages of rapid e l e c t r i c a l energy input short brazing time and good configuration c o n t r o l have been under development through independent sponsorship The prime consideration i n a process for very high temperature brazing i s heat up and cool down time These time requirements d i r e c t l y a f f e c t the resultant base metal properties equipment investment costs t o o l l i f e permissible brazing a l l o y composltlong and production man power costs The d i s t i n c t advantage of rapid processing c a p a b i l i t i e s i s made clear by work which has shown that brazing alloys can be used i f a process f o r heating and cooling permits rapid heating and cooling rates (less than 10 minutes cumulative ti n e above r e c r y s t a l l i z a t l o n ) The development of t h i s c a p a b i l i t y would o f f e r d i s t i n c t advantages over present SQA The secondary factor that a rapid heating-cooling c a p a b i l i t y a f f e c t s i s cost With the use of vacuum radiant f a c i l i t i e s t o t a l in-process times f o r r e f r a c t o r y metal structures can be as high as 2 to 8 hours Consider able reduction i n t h i s processing time i s desired CRITICAL PROBLEMS 1 Materials Basic r e f r a c t o r y metal a l l o y development Is not suggested Braze a l l o y development i s suggested under proposed programs Alloys coatings and Insulation depend on design applications w i t h environmental considerations 2 Coatings Coating development w i l l be required for applications of brazed ref r a c t o r y metal structures above lAOO F These e f f o r t s should be treated separately and not i n t e r f e r e w i t h the basic material and brazing process The recoimsended approach Is to coat sealed brazed panels The selected coating must be compatible with the brazing alloys due to the area of contact at the sealed edged of the panels 3 Hon destructive Testing A serious e f f o r t i s necessary to improve the r e l i a b i l i t y and to reduce the cost of non-destructive Inspection techniques Factors of significance In braze a l l o y development Include braze a l l o y e f f e c t s on base material properties braze a l l o y d u c t i l i t y degree of solutlonlng of the base metal (erosion) high temperature strength thermal s t a b i l i t y and cost The e f f e c t of braze alloys on the base metal i s of major significance as re f l e c t e d by past research which has shown reduced strengths up to 60 percent The cost Is Important since high cost elements such as palladium germanium and gold are candidates for a l l o y additions Under the area of equipment and t o o l costs the I n i t i a l investment for c a p i t a l equipment must be considered For example the selection of vacuum processing would Involve rather high costs f o r the necessary sizes of chambers to produce large s t r u c t u r a l shapes Furthermore the slow in-process times would require multiple units to permit necessary production output rates The problem of brazed structure's dimensional co n t r o l must be approached as a compromise between design and reasonable production c a p a b i l i t i e s The present state of the a i t indicates that these requirements for r e f r a c t o r y metal structures may be d i f f e r e n t than those for lower temperature structures
254 CHART PROPOSED DEVELOPMENT PROGRAM PROGRAM NO. 1 OBJECTIVE To evaluate and optimize the e l e c t r i c blanket process for a p p l i c a t i o n to the brazing of re f r a c t o r y metal structures BACKGROUND Three brazing processes have shown production f e a s i b i l i t y These Include e l e c t r i c blanket vacuum r a d i a t i o n furnace and quartz lamps Specific research and develop ment programs have been government sponsored on the l a t t e r two processes The e l e c t r i c blanket process has been under development through independent sponsorship The I n i t i a t i o n of t h i s program w i l l allow d i r e c t comparisons of the r e l a t i v e worth and production economy of the three processes APPROACH The recommended task should be conducted In four phases Phase I Design and bui l d a prototype apparatus f o r brazing 6 Inch x 6 Inch hardware Use I t to evaluate the basic processing variables OBJECTIVE APPROACH a Emphasis should be on rapid heating and cooling rates to minimize r e c r y s t a l l l z a t l o n In the base material b A useful brazing temperature c a p a b i l i t y of 3000 F Is recommended Phase I I Develop new to o l i n g heater and i n s u l a t i o n materials Task I Develop an e l e c t r i c a l i n s u l a t i o n concept or material for use at 3000 F I t must not a f f e c t the mechanical properties of the re f r a c t o r y base materials Contact during thermal cycling followed by ten s i l e t e s t i n g w i l l be required Suggested base metals Columblum B 66 or D-A2 Tantalum T 111 or T-222 Molybdenum TZM Task I I Develop a thermal i n s u l a t i o n concept or material f o r use at 3000 F I t too must not a f f e c t the mechanical properties of the r e f r a c t o r y metals as established by the above tests The thermal conductivity should be i n the range of current generation Insulation brick for e f f e c t i v e applications Either a castable r e f r a c t o r y such as glass-rock or manufactured b r i c k would be acceptable Design and buil d a small production apparatus for brazing 12 inch 12 inch (or some suitable size) hardware Use i t to produce a maximum of 12 acceptable panels Phase I I I Test the finished panels Evaluate the r e s u l t s F i n a l i z e the design features for building additional apparatus for production ap p l i c a t i o n PROGRAM MO I I To select and^or develop a single or a series of brazing a l l o y s f o r each of three r e f r a c t o r y metal systems Service temperatures are as follows Columblum and Molybdenum 2400 to 2800 F Tantalum above 2800 F 1 Several promising p i l o t brazing alloys have been developed both p r i v a t e l y and under government sponsorship that meet the predicted 3000 F service requirements However d e t a i l s of specific a l l o y compositions are not w e l l publicized A com prehenslve engineering evaluation of these best alloys i s i n order Increase of remelt temperature f o r braze alloys f o r columblum by subsequent thermal treatment has been demonstrated This reactive or regenerative development allows service to as high as 3000 F of a braze Joint made at as low as 2200 F The advantages i n processing and f a c i l i t i e s requirements could be of major importance Continued on next page
255 CHART PROPOSED DEVELOTMENT PROGRAM, continued 2 The following requirements must be evaluated a Brazed Joint shear strength at service temperature b Brazed j o i n t creep strength at service temperature c Brazed j o i n t - coating c o m p a t i b i l i t y d Brazing a l l o y - temperature exposure e f f e c t s on te n s i l e properties of the base material e I n t e r s t i t i a l sink e f f e c t whereby the braze a l l o y becomes embrittled by the base material f Thermal s t a b i l i t y of brazed j o i n t s must be evaluated under c y c l i c and long-time at service temperature exposures g U s a b i l i t y for Joining d i s s i m i l a r a l l o y Joints must be evaluated NOTE I t would be desirable to test a t t r a c t i v e candidate systems using the apparatus proposed i n Program I However t h i s e f f o r t Is needed regardless of the progress of Program I and should not be t i e d to i t unless success so dictates
256 PRIORITY RATING WORKSHEET CHART PRQqpAK^ FACTORS' PR06RAM PROBABIL ITY OF S U C C E S S ⢠L O W Z ⢠MOoeRATC 5 ⢠HIGH 8 C R I T I C A L P R O B L E M S TO B E SOLVED ⢠fe^/Hcrr TOO PIFFWULT Z a S O M E / D I F F I C U L T S D M A N Y / VERY O lFP jCUtT 8 (3R0WTH P O T E N T I A L ⢠LITTLE OR UNDEFINAI»LF O ⢠fieco&HtuaLe poreMTiAL 4 OTHER. THAN AIR FORCE NONe O SOME 4 MAMY 6 FOR AIR FOflCt F U N D I N O D t a w HifiH i m u s T t t V / c T H i f t 6 o » r trrctr if- a e i u u i s i y e Aie F»A£k puuvNi i UKCL>( la. PRocess APPLICATIONS ⢠⢠D N E C E S S I T Y NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH PROBABIL ITY 12 FAIR P R O B A B I L I T Y 8 LOW P R O B A B I L I T Y 4 COMPONENT C R I T l O A L I T Y VERY HKTH n HIAH 9 FAIR 6 LOW 3 F R E a U C N C y OF REQUIREMENT IM S V « r E M MOM THAN 3 C0MP»me«»T9 3 i 3 0«MP«iMeMrS 2 S I N G L E CeMPMilENT I DCSI6N A L T E R N A T E S Ho A L r e R N A T E naeeeen 9 ONC A U T E R M A T E « S E V E I Z . A L A L T E R k l A T E « 3 M A T E R I A L S I M P L I C A T I O N New MATeRiAL vtyltu>ftitHT s e a o 6 MATtKlAL IMPWVEMtNT B £ a P 4 NO P R o & L E M F o i t e s c e i a o CALCULATE PRIORITY STEP I CIRCLE S t e p a RAW SCoOCS roR EACH REFCfteiKU> CoMPCMctrr IN TABteS AT tWD or PAMEt BePetT WITH UAtO TOTBLS ENTEOrP M AT S Y S T E M S AARP RA>M SCORES At L J A fb r n 1 1 /t-to. 1 1 A 3 A \CSt.Ji\-2,')\\3Z\ \ U!*JLJLJL_ 1â1 A3t> n A $e l j F ] [ i e ] [ i a [ l £ 1 1 A-Ufa) L « J L « d L J L _ 1 1 S/^ 1 1 Bfb 1 1 BtbO) ⢠S2c^f»>\(m\33\\S3\\3S 8 2a (a) l i f l l * / ! ! II n S te 1 » 8 l l z * l l x « l l 1 1 l a f l b - V l l II 1 1 0 3c 1 1 ⢠⢠⢠L _ L J 1 1 l_JI_JLJL_ ⢠⢠⢠d L J r n r n n m r n m i ~ n n n r n r n MIGHCST AARP RAW SCORE n s I S IM eACH OTHER S V S T 6 M C IRCLE N E X T HIOHEST SCOSS IF WITHIN 4 POINTS OP TOP SCORB n ^ LOW i NUMBER OF SVSTEMS HldH STEP 3 CIRCLE FREOUENCY DISTRIBUTION PASTOR MUMSen. OP SYSTEM* Hisrt I 2 3 »K M«ce B£LOWi NUMSER. OF SYSTEMS 0 I Z « R M « t e 1 0 1 z \ <f 1 1 1 3 1 H 1 z. 1 *f 2. TOTAL PRIORITY (Tj
TITLE BRAZING SUPERALLOYS AND STAINIESS STEELS AND SKIN STRINGER STRUCTURE 257 HONEYCOMB COMBINATIONS CHART NO 4 ^ PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Join various assembly d e t a i l s by brazing of superalloys and stainless steel f or service temperature from 800 F to 2300 F Typical applications are j o i n i n g of edge members of very large honeycomb panels of t h i n honeycomb sections to faces of forged and cast sections to sheet of sheet tube and plate members In s t i f f e n e d panel assemblies Brazing must not erode t h i n sections nor degrade heat treatment response of materials AARP REFERENCES E C h a r t s . 8 Char ts . 20 61 62 92 93 113 216 271 309 310 11 30b c 41b c 50a 51a b 107d 122b 146 147 P4FVPS C h a r t s . Joining No 12 APPLICABLE PROCESS Brazing by one of the following depending on end item (1) ELECTRIC BLANKET (2) FURNACE BRAZING (VACUUM AND RETORT) (3) RESISTANCE HEATING OF CERAMIC TOOLS (4) RADIANT LAMP HEATING (5) IMMERSION] (SALT OR METAL) 6 05 11 6 05 04 6 05 09 Code 6 05 01 6 05 03 STATE OF THE ART ASSESSMENT Development e f f o r t s i n brazing superalloys and stainless steels have been under way since early 1951 The o r i g i n a l concept of brazed honeycomb sandwich panels had I t s o r i g i n with the stainless steels The number of base metal alloys i s now quite extensive i n the three base metal groups i r o n base nickel base cobalt base The following alloys are examples of prime candidates at t h i s time 1 Iron Base A286 2 Nickel Base non-heat treatable excellent oxidation resistance Hastelloy X 3 Nickel Base excellent w e l d a b l l l t y plus high temperature strength Inconel 718 4 Nickel Base high strength at high temperature Udimet 700 5 Nickel Base dispersion strengthened TD Nickel 6 Cobalt Base HS 25 (L605) In the area of brazing a l l o y development most of the spe c i f i c e f f o r t s have been of l i m i t e d scope That is one spec i f i c a l l o y and/or application has been involved Because of t h i s l i m i t a t i o n a vast amount of data i s available on a large number of s t r i k i n g l y similar brazing alloys Two basic brazing a l l o y systems encompass roost of the alloys with only a few exceptions They are precious metal base and nickel base Only a l i m i t e d amount of basic new brazing a l l o y development work has been reported Most of the reported successful results have required some processing gimmick to overcome the inherent c h a r a c t e r i s t i c s of the available brazing alloys A review of reported information has shown that the following l i s t e d alloys are of the best available For Iron Base Superalloys (1) Nl Cr Si For Nickel Base Superalloys (1) Nl Mn Si Cu (2) Au Nl-Cu (3) Nl Cr Mn Si (4) Au Pd Nl (5) Pd Nl Cr (6) Mn Nl-Co B (7) Pd Nl-Cr-Si (8) Nl-Cr Si (9) Cu-Mn-Co-Nl For Cobalt-Base Superalloys (1) Au Pd-Ni (2) Nl Cr Si (3) Co Nl Cr Si W B (4) Pd Nl Cr ALTERNATE PROCESSES NONE Code
258 STATE OF THE ART ASSESSMENT, continued CHART In the area of brazing process development many methods of obtaining the high temperatures necessary for brazing have been evaluated as l i s t e d i n the applicable processes Processing techniques for the production of high q u a l i t y superalloy sandwich panels i n volume have been proven by both the furnace and e l e c t r i c blanket brazing approaches Quartz lamp approaches have had extensive research experience w i t h some production h i s t o r y Immersion brazing has had exploratory research and o f f e r s one p o s s i b i l i t y of a continuous process F a c i l i t i e s and production know how are available at more than one aerospace f a c i l i t y for the applic a t i o n of furnace and e l e c t r i c blanket approaches to brazing superalloy sandwich panels They are c u r r e n t l y proven for use around 2050 F CRITICAL PROBLEMS Several problems i n the development of brazing alloys must be given careful consideration One of these is brazing temperature I t is desirable from a heat t r e a t i n g standpoint and in som° cases necessary from a physical metallurgy standpoint to braze the heat treatable super alloys at t h e i r respective solution t r e a t i n g temperature Most of the brazing investigations reported to date have been directed to t h i s aim To provide some idea of the problem t h i s factor creates the following l i s t presents the solu t i o n t r e a t i n g temperatures of the applicable superalloys A 286 1800F Hastelloy X Non heat treatable Inconel 718 2150 F Udimet 700 2150 F TD Ni Td-Nl-Cr Dispersion Agglomerates at 2500 F HS 25 Non heat treatable These temperatures should not be exceeded I t is evident that some means of increasing the remelt temperature of brazed Joints would be desirable This can be accomplished by d i f f u s i o n and a l l o y i n g or by the addition of raw powders (such as the base metal i t s e l f ) to the brazing alloys Most of the ni c k e l base btazing alloys show a serious solutlonlng of the base metals during the brazing process Some of the alloys have been made usable by employing rapid heating and cooling cycles to minimize the time at temperatures With the consideration of the d e s i r a b i l i t y of using the remelt r i s e phenomenon longer times at temperature may be necessary Therefore means of reducing or eliminating the solutlonlng would be desirable One approach is to develop a new a l l o y free of the solutlonlng elements The addition of elements to t i e up the solutlonlng elements has shown promise (e g Co reduces the solutlonlng by Ni) and of f e r s another approach A major problem is the d i f f i c u l t y encountered with wetting the superalloys This is p a r t i c u l a r l y true of the heat treatable alloys which contain small amounts of titanium and aluminum for heat t r e a t response These elements form tenacious complex surface oxides which are hard to break down Work has shown that the w e t t a b i l i t y of these alloys varies inversely with titanium and aluminum content Likely approaches to t h i s problem include the addition of wetting agents i n the brazing alloys such as l i t h i u m f l a s h p l a t i n g w i t h Ag NI etc or the use of reducing atmospheres such as hydrogen or hydrogen plus i n e r t gas mixtures Other factors which must be considered include galvanic corrosion with the noble brazing alloys elevated temperature oxidation resistance c o m p a t i b i l i t y w i t h coatings braze a l l o y d u c t i l i t y high temperature strength s t a b i l i t y under c y c l i c temperature conditions and cost In the area of process development improvement w i l l be required to permit higher pro cessing temperatures w i t h the non heat treatable alloys and TD Nickel Improved thermal and e l e c t r i c a l i n s u l a t i o n w i l l be required Improved packaging w i l l be needed due to more rapid oxidation at the higher temperature Tooling methods equipment and processes must maintain close thermal and dimensional tolerances One area of considerable importance and which is a continuing problem Is the q u a l i t y c o n t r o l of brazed sandwich structures The three p r i n c i p l e methods of non destructive t e s t i n g and inspection radiographic thermographic and u l t r a sonic are expensive to i n s t a l l and operate Furthermore each has i t s own peculiar l i m i t i n g factors necessitating the use of two or more Continued on next page
CHART -259 CRITICAL PROBLEMS, continued Inspection techniques to determine such factors as core to skin attachment faying surface voids and edge t i e attachment Some q u a l i t y control procedures are l i m i t e d by face sheet thicknesses that can be Inspected Radiographic Inspection and thermographic Inspection are also l i m i t e d I n t e r n a l f i t t i n g s which are brazed as an Int e g r a l part of the sandwich structure and which present more than two braze surfaces have defied a l l presently known Inspection techniques PROPOSED DEVELOPMENT PROGRAM OBJECTIVES To develop high w e t t a b i l i t y non-solutlonlng alloys for stainless and superalloys high strength at temperature braze APPROACH 1 A basic brazing a l l o y laboratory type development program should be undertaken Workable means of showing the remelt temperature r i s e phenomenon should be emphasized During the development of optimum alloys c o m p a t i b i l i t y must be maintained w i t h the applicable brazing methods and processes Either the a l l o y must be t a i l o r e d to the process or the process adapted to the a l l o y 2 I t would be desirable to establish the goals of developing brazing alloys for stated temperature l i m i t s for a Maximum temperature service w i t h non heat treatable alloys such as TD Ni and Ti-Nl-Cr and HS 25 b Use wit h heat treatable nickel alloys w i t h a brazing temperature compatible with the a l l o y and heat t r e a t requirements which w i l l allow maximum temperature service of the structure 3 Small v e r i f i c a t i o n projects Bhould be i n i t i a t e d that w i l l e s t a b l i s h stimulate and make public state of the a r t claims or well founded unso l i c i t e d proposals at appropriate points i n time coincident with braze product development Many Ideas and Independent research programs e x i s t i n Industry r e l a t i v e to brazed superalloy structure Once the i n i t i a l step of basic braze a l l o y development i s undertaken supporting research i s needed Numerous small programs i n the process f i e l d such as packaging materials e l e c t r i c a l and thermal i n s u l a t i o n atmosphere protection and general production approaches would be i n order By encouraging more small programs information w i l l be generated for use i n Industry U Evaluation of braze alloys should include a Brazed Joint shear strength at room and anticipated service temperature b Extent of the base metal erosion problem c Corrosion and oxidation resistance of brazed Joints d Brazed Joint peel strength Quality control developijents must accompany a l l o y process and methods advancements Improved non destructive methods are needed that w i l l establish braze j o i n t i n t e g r i t y
260 PRIORITY RATING WORKSHEET PROfiRAM PACTDRS PR06RAM OF S U C C E S S P R O B A B I L I T V P L O W yl M O O E R A T E a HicH C R I T I C A L P R O B L E M S TO B E SOLVED a FtW(/MOT TOO PIFFWULT 9 0 M e / D I P F l C U t T ⢠M A N Y / VERY P IFP ICUtT PROCeSS G R O W T H P O T E N T I A L ⢠LITTLE OR U N D E F I N A e L F ;& geeo&Hn*»i.e porcMTiAL APPLICATIONS OTHER THAN AIR F O R C E ⢠NONE K SOME ⢠MANY N E C E S S I T Y FOR AIR FORCE FUNDINQ D L e w HifiH i N t a S T a v / c T H c A <3mr SFfetr 4. ' r i Eiccuisii^e A I R Foftck F U M P M * U K E L X i t z 5 8 2 9 6 O 4 O 4 0 NEED FACTORS S Y S T E M S P R O B A B I L I T Y man P B O B A B i L i T Y FAIR P R O B A B I L I T Y L O W P R O B A B I L I T Y COMPONENT CRITlCALITY VeBY HICH HIAH FAIR L e w F R e a u C N C V OF REaUIREMENT m « V « r E M MABC THAM 3 CCMP»NeHT9 £ 3 COMPoNEMrS S i N f i L E ^DMPeNENT DEStCN A L T E R M A T E S No ALTCBNATe RweseEN OHt ALTEBNAte S E V E M L ALTERWATeC M A T E R I A L S IMPLICATION New M A T E f c i n i . p e v e u > p u C N T s e a o IVUTCRIAL IMPMVCMCNT CElB O He P R s e u E M F o d c s c e i d 12 8 9 S 3 2 I 6 3 6 4 o CALCULATE STEP I STEP 2 9 Z6 RAW sco«es Foe. EACH REFCCeNOP COMIVMCtlT M TABteS AT bXB o r PANEL ttep«iT W I T H liAW TeTALS ENTEOrp M CHART ^. ^ NO ¥/9 /if A A R P RA>M SeotUS [?rniyirg»] i II [ i 7 ] [ ^ a a a 32^6) 175^1 II II ^ r ~ i g^tf 1 ^ 1 11 II II I Bze \Jo\\ II 11 II i B3e. II II II I ⢠⢠⢠⢠⢠⢠0 1 ⢠⢠⢠⢠⢠PRIORITY- CIRCLE HlflHEST AARP RAW SCORE n a IN EACH OTHER SV6T6M CIRCLE NEXT HIOHEST IF WITHIN 4 POINTS OP TOP S C O R t n NUMBER OF ^VSTEMS HIAM ^ tOW ^ 3S- s c c e c STEP 3 CIRCLE FREOUENCY DISTRIBUTION FACTOR f BELOW. I 2 3 NUM&eR O F SY9T«MS bow 0 I 2 R K I O O E t 0 1 a 1 ^ 1 1 1 3 1 f 1 z 1 «!⢠C . 4 > p = n»f = TOTAL= 2 6 _2L5L PRIORITY
-261 TITLE BRAZING OF DISSIMILAR METALS AND OF CERAMICS TO METALS CHART PRIORITY â¢eUTED CAMR CHAITS MANUFACTURING REQUIREMENT To Join by brazing various combinations of dissimilar metals and of ceramics to metals for applications involving r e l a t i v e l y high temperatures and i n some cases an oxidizing environment or a corrosive l i q u i d metal environment Typical components are heat shields nose cones leading edges nozzle Inserts guide vanes combustion chambers seal AARP REFERENCES E C h a r t . _ ^ _ i L 45 64 69 98 269 28c 29b 30d 41d, B Chort« P&FVPS Chnrt. Joining No 2. 3. 4. 6. 7 120a.c. 121a.c. APPLICABLE PROCESS BRAZING (by one of the following depending on end ltem)| 1 ELECTRIC BLANKET 2 FURNACE BRAZING (Vacuum and Retort) 3 RESISTANCE HEATING OF CERAMIC TOOLS 4 RADIANT LAMP HEATING Code 6 05 11 6 05 01 6 05 04 6 05 03 STATE-OF THE ART ASSESSMENT The following brazing combinations of materials with d i f f e r e n t physical and mechanical properties are considered Category A Ceramic to-Refractory Metals Category B Ceramlc-to Superalloys Category C Refractory to Superalloys A large number of ceramics refractory metals superalloys and titanium are available for consideration The following combinations are l i k e l y candidates today (A) Zirconium oxide to B66 columblum (B) Zirconium oxide to HS 25 and (C) T 111 tantalum to HS 25 Only a limited amount of work has been done i n the area of ceramic to metal and of dissimilar metal brazing The reported results with certain combinations have been quite promising The best successes have been when careful attention has been given to j o i n t design Good results have been reported on counter bored tubing Joints between zirconium oxide and columblum using titanium base brazing alloys With these Joints the design minimizes the d i f f e r e n t i a l thermal expansion by keeping the linear contact area between the metal and the ceramic In any one dir e c t i o n small Another approach has Involved Joints between aluminum oxide and superalloys A ductile controlled r a t i o zirconium s i l v e r a l l o y has been developed which matches the thermal expansion of the ceramic and absorbs the s t r a i n from the metal to a degree s u f f i c i e n t for successful j o i n t s The classic approach to the thermal expansion mismatch problem s t i l l remains the most widely used concept I t involves the use of a series of one or more layers of intermediate materials Co provide for the mismatch i n steps The best reported results on glass to refractory metal or superalloy brazing were found in the f i e l d of electronics Most of the Joints u t i l i z e lower melting point solders Problems in wetting have been improved with reducing atmospheres such as hydrogen or the use of special fluxes ALTERNATE pjtOCE^SES" Continued on next page Code
â¢.262 STATE OF THE-ART ASSESSMENT, continued Limited successful published r e s u l t s are available i n the f i e l d of brazing r e f r a c t o r y metals to the superalloys With many commercial brazing a l l o y s problems have been encountered wi t h low melting eutectlcs (Ni-Cb Co-Cb etc ) and poor wetting Promising r e s u l t s have been obtained w i t h the following brazing alloys (1) Nl-Sl-Fe-Cr-Co-W-B (2) Nl-Cr Mi Fe-Co W and (3) Pd Ni Materials development of basic ceramic and compatible metal all o y s systems i s not suggested Braze a l l o y development is, suggested under proposed programs Certain s p e c i f i c requirements may arise as a r e s u l t of new design concepts or environmental considerations These needs cannot be predicted at t h i s time and therefore such development i s not recommended Coating development w i l l be required depending on the temperature l i m i t a t i o n s of the m e t a l l i c p o r t i o n o f the assembly This should be treated separately and not I n t e r f e r e w i t h the basic material and brazing process Quality c o n t r o l of brazed ceramic t o metal and dissimilar-metal Joints at present i s based on the techniques used for the respective metal-to-metal Joints Typical of these are x-ray ultrasonics and i n f r a r e d Normal state of the a r t advancements i n these areas w i l l probably s a t i s f y the requirements i n the future Development of new brazing alloys for the Joining of d i s s i m i l a r metals and of ceramic to metal combinations should be supported PROPOSED D E v a o m m mOWMA OBJECTIVE To develop brazing a l l o y s for various dlBslmilar material combinations APPROACH Phase I A laboratory scale brazing a l l o y development program should be undertaken during which the a p p l i c a b i l i t y of representative brazing processes would be determined by d i s s i m i l a r material combinations such as given below Material compositions suggested are based on current expectations of future usage MATERIAL COMBINATIONS Refractory metals to low thermal c o e f f i c i e n t ceramics Superalloys to low thermal c o e f f i c i e n t ceramics Braze temperature Service temperature Suggested materials Specific requirements to emphasize I n 2400F range or below r e c r y s t a l l a t i o n of r e f r a c t o r y a l l o y s 2500 F A single r e f r a c t o r y metal (Columblum B 66 a l l o y ) and a ceramic (Zr02) are recom mended a Thermal shock resistance of Joints under t y p i c a l operating stresses b Brazed Joint shear strength at room and a n t i c - ipated service temperature In 2300F range l i m i t e d by agglomsratlom o f dispersion strengthened a l l o y s 2300F A single superalloy (HS 25 or TD-Ni-Cr) and a ceramic (Zr02) are recommended a Thermal shock resistance of j o i n t s under t y p i c a l operating stresses b Brazed Jo i n t shear strength at room and a n t i c ipated service temperature Continued on next page
263 PROPOSED DEVELOPMENT PROGRAM, c o n t i n u e d CHART MATERIAL COMBINATIONS cont d S p e c i f i c r e q u i r e m e n t s t o emphasize R e f r a c t o r y metals t o low the r m a l c o e f f i c i e n t ceramics c Atmosphere and/or f l u x r e q u i r e m e n t s f o r the pro d u c t i o n o f r e l i a b l e braze ments d Thermal s t a b i l i t y S u p e r a l l o y s t o low ther m a l c o e f f i c i e n t ceramics c Atmosphere and/or f l u x r e q uirements f o r the produc t l o n o f r e l i a b l e brazements d The e f f e c t o f s u r f a c e pre t r e a t m e n t o f the ceramic m a t e r i a l e Thermal s t a b i l i t y The p r i n c i p a l problem i n these c a t e g o r i e s i s the s i z e a b l e d i f f e r e n c e t h a t e x i s t s between the thermal c o e f f i c i e n t o f expansion o f ceramics compared t o metals The amount of m a t e r i a l expansion and c o n t r a c t i o n which i s i n v o l v e d i n h e a t i n g and c o o l i n g c y c l e s from room temperature t o the 1800F and above range i s s u f f i c i e n t t o cause r u p t u r e I n the ceramic S e v e r a l approaches t o overcome t h i s problem m e r i t c o nsider a t i o n One i n v o l v e s s e l e c t i n g m e t a l t o cermaic combinations t h a t approach each o t h e r I n expansion c h a r a c t e r i s t i c U s u a l l y the best metal c a n d i d a t e i s one whose product o f thermal expansion c o e f f i c i e n t times modulus o f e l a s t i c i t y i s low Columbium and z i r c o n i u m are t y p i c a l c a n d i d a t e s Another approach i n v o l v e s the development o f a b r a z i n g a l l o y which has expansion c h a r a c t e r i s t i c s which e i t h e r match the ceramic or f a l l between I t and the meta l A t h i r d approach i n v o l v e s d e s i g n i n g j o i n t s whose l i n e a r area o f c o n t a c t i n any one d i r e c t i o n i s v e r y s m a l l t o minimize the t o t a l d e f o r m a t i o n below the v a l u e s which cause f a i l u r e Another problem area w i t h ceramic t o m e t a l j o i n i n g I s the w e t t i n g o f the ceramic by molten b r a z i n g a l l o y s Present approaches t o t h i s problem i n c l u d e the use of (1) f l u x e s (2) h i g h l y r e a c t i v e b r a z i n g a l l o y a d d i t i o n s (3) r e a c t i v e b r a z i n g atmospheres or (4) m e t a l l i c c o a t i n g on the ceramic p r i o r t o b r a z i n g Braze temperature S e r v i c e temperature Suggested m a t e r i a l s S p e c i f i c r equirements t o emphasize MATERIAL COMBINATIONS S u p e r a l l o y s t o r e f r a c t o r y a l l o y s I n 2150 F range t o minimize s o l u t l o n i n g problem and p o t e n t a l low m e l t i n g e u t e c t i c s between the two systems 1800 F To s i m p l i f y the i n v e s t i g a t i o n o n l y a s i n g l e c a n d i d a t e r e f r a c t o r y m e t a l and s u p e r a l l o y should be chosen Columbium A 66 a l l o y and c o b a l t base HS 25 a l l o y r e s p e c t i v e l y are recommended a Brazed j o i n t shear s t r e n g t h a t room and a n t i c i p a t e d s e r v i c e temperature b E x t e n t o f the e r o s i o n problem p a r t i c u l a r l y i n the s u p e r a l l o y c C o r r o s i o n and o x i d a t i o n r e s i s t a n c e o f the j o i n t s d Thermal s t a b i l i t y e Brazed j o i n t p e e l s t r e n g t h
264- NO fAh PROPOSED DEVELQPMEWr PROGRAM, contlnupd In bracing the refractory metals-co-superalloya the principal problem Involved i s the harmful bracing alloy base metal reaction such as low melting eutectlcs The refractory metals form low melting eutectlcs with Fe Ni and Co These values with Cb are 2430 F 2310 F and 2250 F respectively One approach to solving this problem Involves limiting the bracing and service temperatures below these values However only a limited number of bracing alloy candidates w i l l melt In this range of temper ature The precious metal alloys offer usable melting temperatures but do not have sufficient high temperature strength Titanium-base brazing alloys already proven applicable with the refractory metals may prove usable with modification Ihe other problem which stands out i s the need for improved wetting In brazing allays for the superalloys Exploratory work has indicated that the titanium base brazing alloys w i l l be adequate in this respect I t I s assumed that e x i s t i n g proven brazing processes can be u t i l i z e d These include furnace brazing e l e c t r i c blanket brazing quartz lamp brazing torch blazing and others The development e f f o r t s should be directed toward one or more of these processes Phase I I Upon successful development of promising combinations o f materials and processes a second phase program i s recommended This phase would be to develop representative hardware around which processing information and design data would be established and v e r i f i e d
265 P R O C E S S APPLICATIONS n K ⢠NeCESSITY ⢠LOW HiaH i>it«siev/cTH£* s « r CFFOCT <f ⢠McocftATE - Scut BTfmx ofHes. ^ouaeâ¬9 e NEED FACTORS S V S T E M S P R O B A B I L I T Y HIQH P B O B A e i L l T Y FAIR PROBABILITY- LOW P R O B A B I L I T Y COMPONENT C R I T l C A L l T Y Venv H I C H H l f t H FAIR L O W F R e O U E N C V OF R E Q U I R E M E N T IN S V S T E M MORE T H A N 3 C0MPI>«'eMT9 2. 3 0«MP(iMeMrS S I N f l L E flOMPeNeWT OeS lSN A L T E R M A T E S No A L T E R N A r e R « E e e e N ONE A t - T E H N A T e S E V E R A L A L T E R M A r e e MATERIALS IMPLICATION NEW M A T E H l f l L P £ V £ U ' f « « £ N T R C a O MATERIAL I M P d O V E M E M T R E S D NO P R e S L E M T o c c s c e i d CALCULATE PRIORITY PRIORITY RATING WORKSHEET P B 0 6 R A M FACTOaS PROaRAM PROBABILITY OF S U C C E S S ⢠LOW Z X M O D E R A T E 5 ⢠H I 6 H 8 CRIT ICAL P R O B L E M S TO B E SOLVED a F E W / N O T TOO P I F F U J O L T 2 ⢠S O M E / D I F F I C U L T S >f M A N Y / VERY DIFFICULT 8 G R O W T H P O T E N T I A L LITTLE OR UNDEFINABLE O ⢠RECOSNaABLE PorENTIAL 4 OTHER THAN AIR FORCE NONE O SOME 4 MANY 6 FOR AIR FORCe F U N D I N O 6 RAW S C O R E S FOR E A C H REFceeMAP CoMFONt l /T IN T A B L E D AT t N B or PAMEt 12tP«C.T W I T H VAIO T o T r t u S E N T E R T P IN W CHART S V S r e M S A A R P RANM SCOWS k 1 1 i 7 1 1 1 31 L _ J 1*7 r i 3 A \m 1Ì | 3 2 . [13 LJ rn 3 b 1 2 6 LJ 1 1 1 1 LZ] B la. 1 2 ^ [ I T ] 1 rn S li» 1 1 LJ 1 1Ì B 2«^z) 1 Z9 1 n ⢠B 2A I 28 ⢠⢠I 1 1 2-<Ì LJ 1 n 1 1 1 1 1 U U LJ L J m 1 1 rnr- inmri r n r n r n m r - i S T E P I S T E P 2 S T E P 3 C I R C L E HiaHCST A A R P R A W SCORE IN E A C H O T H E R S Y S T E M C I R C L E N E X T H I C H E S T S C O R E I F W I T H I N ^ P O I N T S O F T O P S C O R E n ^ LOW ^ N U M B E R OF S Y S T E M S HIAH CIRCLE FREQUENCY DISTRIBUTION FACTOR NUMseR. OP sysreMS ri>ert I 2 . 3 »K MME BEUOWc N U M & E R OF S Y S T E M S L e v < D 1 2 i tMoltc 1 0 1 a I 4 1 1 1 3 1 *f 1 £ 1 «f TOTAL PRIORITY
-266 TITLE BRAZING TITANIUM ALLOYS CHART PRIORITY ¥ , 2 7 JZL R E U T E O CAMR CHARTS MANUFACTURING REQUIREMENT Join titanium d e t a i l s by brazing for applications such as primary load bearing structures and large honeycomb and m u l t i wall sandwich assemblies where service temperatures range from 250 to approximately lOOOF An additional requirement is for a crushable cluster of tubes to absorb landing energy where uniform compression strength i s required a f t e r stowage at temperatures as high as 1800F Thermal protection i n the stowage compartment may be used to hold temperatures lower compatible with l i m i t i n g temperatures for the al l o y or brazed Joints AARP REFERENCES E Chart . UX. 12J- , lllL. Zaa, ^ O * ^ , B Chart. 50a. 97b. 107d. 108a. 109b. 111b. 134a. 138b. 148b. 153a.b. 172a. 176 PAFVPS Char t t . APPLICABLE PROCESS One of the following depending on end item (1) ELECTRM <: n Coda^ BLANKET (2) FURNACE BRAZING (VACUUM AND RETORT) (3) RESISTANCE HEATING OF* " " CERAMIC TOOLS (4) RAOIANI LAMP HEATING (5) IMMERSION (SALT OR METAL) 6 05 04 6 05 03 6 05 09 STATE-OF THE ART ASSESSMENT Development e f f o r t s i n t h i s materials area have been underway since 1955 Many of the processing and a l l o y developments have been borrowed from p a r a l l e l e f f o r t s w i t h stainless steel These techniques have been quite well proven with titanium therefore l i t t l e or no new process concepts have been pursued Furnace e l e c t r i c blanket I n t e g r a l l y heated ceramic brazing and quartz lamps have been proven e f f e c t i v e with titanium Several production configuration brazed honeycomb structures have been successfully produced and evaluated on modern a i r c r a f t Immersion heating In a solution of s a l t molten metal or glass has been explored i n research A conveyorlzed continuous system is possible which at the same time furnishes heat l i q u i d pressure and atmosphere control Objections Include dangers of leaks and thermal buckling during Immersion Sizeable e f f o r t s i n the area of brazing alloy development have been undertaken and completed Two categories of alloys have been considered Type No 1 - Alloys which are brazed i n conjunction with solution t r e a t i n g (1450 1700F range) The most popular of these alloys are of the Ag Al family Type No 2 Alloys which are brazed i n conjunction w i t h short time aging (lOOOF range) A successful allo y evaluated i n th i s category to date i s Ag-Cu-Ge Alloys of Type No 1 ( s i l v e r aluminum family) have been w e l l proven and are commercially available Alloys of Type No 2 have been developed and tested to a li m i t e d degree D i f f i c u l t i e s have been encountered i n obtaining necessary strength at temperature with t h i s a l l o y A basic problem with s i l v e r base alloys i s galvanic corrosion under long time exposure ALTERNATE PROCESSES NONE Code
267 CHART. NO T ^ V CRITICAL PROBLEMS The development of brazed titanium s t r u c t u r e s for production a p p l i c a t i o n has progressed into the a p p l i c a t i o n stage A d i s c u s s i o n of the problem areas therefore i s confined to those representing p o t e n t i a l improvement The S l i v e r aluminum a l l o y s developed and proved for use with titanium in 1959 perform quite s a t i s f a c t o r i l y Corrosion problems have been reported between s l i v e r and titanium Problem a l l o y s need to be i d e n t i f i e d and new a l l o y s developed such as T i Zr Be which may be a candidate for some a p p l i c a t i o n s The p r i n c i p a l l i m i t a t i o n i s high d e n s i t y With s t a i n l e s s s t e e l t h i s factor seems small (Ag 0 38 Ib/cu in ) (Fe 0 28 Ib/cu i n ) However with titanium and I t s low density advantage (0 16 Ib/cu i n ) the weight of the s i l v e r becomes a s i g n i f i c a n t factor The development of new low density brazing a l l o y s could represent a s i z e a b l e weight reduction factor No such promising a l l o y s have been reported although l i m i t e d development work i s under way In the area of the brazing process the major problem area to consider i s the reduction of costs The f a c t o r s which most a f f e c t these high c o s t s are the extensive care in c l e a n i n g and lay up required the i n e r t gas or vacuum atmosphere welded packaging and the long c>cle times required by the batch process With the use of heat t r e a t a b l e a l l o y s i t i s d e s i r a b l e to heat t r e a t the s t r u c t u r e in the brazing f i x t u r e With the use of such s t r u c t u r e s above 800F problems may be encountered with e f f e c t of thermal c y c l e s required by subsequent coating operations One area of considerable importance and which i s a continuing problem i s the q u a l i t y c o n t r o l of brazed sandwich s t r u c t u r e s The three p r i n c i p a l methods of non d e s t r u c t i v e t e s t i n g and inspection radiographic thermographic and u l t r a s o n i c are expensive to i n s t a l l and operate Furthermore each has i t s own p e c u l i a r l i m i t i n g f a c t o r s n e c e s s i t a t i n g the use of rwo or more in s p e c t i o n techniques to determine such f a c t o r s as core to s k i n attachment faying surface voids and edge t i e attachment Some q u a l i t y c o n t r o l procedures are l i m i t e d by face sheet thicknesses than can be inspected Radiographic inspection and thermographic inspection are a l s o l i m i t e d I n t e r n a l f i t t i n g s which are brazed as an i n t e g r a l part of the sandwich s t r i c t u r e and which present more than two braze surfaces have defied a l l p r e s e n t l y known insp e c t i o n techniques PROPOSED DEVELOPMENT PROGRAM PHASE I Braze A l l o y OBJECTIVE Development of a new low d e n s i t y brazing a l l o y i s i n order A s e n s i b l e goal to shoot for would be a density of 0 2 Ib/cu i n As new titanium a l l o y s are developed with increased s e r v i c e temperature a d d i t i o n a l brazing a l l o y development w i l l be required APPROACH I n i t i a t e exploratory research to develop brazing a l l o y s compatible to the d e n s i t y and properties of titanium Several small programs would be d e s i r a b l e to support and make public work being explored by p r i v a t e concerns As promising m a t e r i a l s develop expand the program to production demonstration s i z e s Continue develop ment of new a l l o y s as s e r v i c e temperature of titanium i n c r e a s e s Program should involve both a l l o y development and product a p p l i c a t i o n types Quality c o n t r o l and non d e s t r u c t i v e t e s t i n g considerations should be a part of a l l o y study Associated c r i t e r i a should be considered and reported PHASE I I Continuous Braze Process OBJECTIVE Develop a simple continuous brazing process that w i l l braze d i f f e r e n t s i z e s and c o n f i g u r a t i o n at reduced cost as compared to present custom batch processes Continued on next page
CHART 268 PROPOSED DEVEL(gMEWr PROGRAM, continued BACKGROUND Present production methods require custom tooling and heating or are oven loaded as a batch process Custom designs and methods have made the a p p l i c a t i o n non competitive Titanium i s the preferred m a t e r i a l for which the continuous process should be developed because of i t s a t t r a c t i v e strength-weight and c o r r o s i o n r e s i s t a n t p r o p e r t i e s for aerospace a p p l i c a t i o n s However once developed the continuous process should be adaptable to other m a t e r i a l s APPROACH Quartz lamp and immersion brazing both o f f e r a continuous manufacturing approach as compared with r e s i s t a n c e heated tools e l e c t r i c blankets etc Since brazing occurs a t a r e l a t i v e l y low temperature continuous ovens r a d i a n t lamp systems immersion or others should be developed to o f f e r an economical approach Cost of brazed s t r u c t u r e must be reduced More s i m p l i f i e d and r e l i a b l e supporting systems must be considered such as cle a n i n g lay up f i t t i n g requirements atmosphere co n t r o l heat t r e a t c y c l e vs braze c y c l e e tc The program should involve the e n t i r e brazing system and attempt to make brazing a competitive process I t s s t r u c t u r a l advantages are known Included i n the program should be a projected parametric cost a n a l y s i s of shapes and s i z e s as required by predicted v e h i c l e s I n s p e c t i o n c r i t e r i a of the m a t e r i a l s and systems should be an I n t e g r a l part of the program The program should be production oriented
269 PRIORITY RATING WORKSHEET CHART p R Q q p A » / | F A C T O R S ' PR06RAM PROBABILITY OF SUCCESS D LOW 2 ^ MOoeRATC 5 ⢠HICH 8 CRITICAL PROBLEMS TO BE SOLVED ⢠FEN^/NOT TOO DIFFICULT 2 S O M E / D I F F I C U L T S a MANY/ VERY DIFFICULT 8 PROCeSS G R O W T H P O T E N T I A L n LITTLE OR ONDEFINAOLE O >C flECodHiinBie poreuriAL 4 APPLICATIONS OTHER TWAN AIR FORCE ⢠NONE O ^ SOME 4 D MANY e NECESSITY FOR AIR FORCE FUNDINQ ⢠LOW HifiH iMtuSTKV/'orHee S « r CFFeir * ^ MOOESATB - SCMf EFRKT OTMOt «Me<!£3 0 ⢠txcui%ii/e A I R Foftct F U M P M S U K E L W IT. N E E D F A C T O R S S Y S T E M S P R O B A B I L I T Y H I O H P R O S A B I I T Y FAIR PROBABILirr LOW PROBABILITY COMPONENT CRITICALITY VERY H I C - H H I « H F A I R Low FREQUENCY OF REQUIREMENT IN SYSTEM MORE THAN 3 COMPONENTS Z 3 COMPONENTS S l N f l L E CetAPCNf.KT O e S l S N ALTERMATES No ALTEBNATE RwESEEN ONE ALTERNATe SEVERAL ALTERNATE* MATERIALS IMPLIC/^riON New MATEAiflL pevtLoFMENT eea v IVMTtBlflL IMPdOVEMENT EElB'D NO PROBLEM Foe.e?eeki 12 8 4 14 9 6 3 3 2 I <) 6 3 « o CALCULATE P R I O R I T Y STEP I S T E P Z 8 2^ RAW rod EACM REFEKENrtP COMFONENT IN TABLES AT tND OF PANEL fcP»t.T W I T H R A W T O T A L S ENTEOCP IN QOWMAItV AT IZISUT SVSTtMS ^ / ^ BZa. 8 3i Bn C 3m. C ^ AARP RA>M seoRCS CIRCLE HIGHEST AARP RAW S C O R E nr. IN EACH OTHER S V S T E M C I R C L E NEXT H I G H E S T IF WITHIN 4 POINTS OF TOP S C O R E 36 NUMBER OF SYSTEMS H l d H tow S T E P 3 C I R C L E NUMBER. OF SYSTEMS LOW FREQUENCY DISTRIBUTION FACTOR NuMoen. OP sysTfiMs HiaM I 2. 3 SR MMLE SCORE B£LOWt 0 I 2 AMO«C 1 0 1 a I 4 1 1 1 3 1 f t 2. 1 f 2£ J / I 3o 11 Jo I ⢠â¢cz: J C ? 3 C Z ] ] ⢠⢠⢠⢠TOTAL PRIORITY CD
270 TITLE FUSION WELDING OF HIGH STRENGTH METALS IN THICK PLATE CHART PMORmr RELATED CAMR CHARTS MANUFACTURING REQUIREMENT J o i n component p a r t s by f u s i o n welding to produce s t r u c t u r e s I n the following m a t e r i a l s and t h i c k n e s s e s 1 2 3 Nickel-base p r e c i p i t a t i o n strengthening s u p e r a l l o y s I n thickness to one Inch High strength s t e e l p l a t e s and c a s t i n g s I n thickness of one and two Inches Alpha-beta and beta titanium a l l o y s I n t h i c k n e s s of one to three Inches These weldments c o n s t i t u t e r i g i d s u bstructures for the hypersonic c r u i s e v e h i c l e s where c l o s e dimensional tolerances are required and s o l i d rocket motor cases and t h r u s t s t r u c t u r e for launch systems where dimensions are as large as 50 f e e t diameter and 160 f e e t long AARP REFERENCES E Chart . 60. 151, 167, 171 B f h n ^ . 31d 83a. 93 P4FVPS Ch«.«. J o i n i n g No 13 APPLICABLE PROCESS One of the following depending on end Items PLASMA ARC TUNGSTEN INERT GAS OR ELECTRON BEAM FUSION WELDING Code 6 01 11 6 01 01 6 01 12 STATE-OF THE-ART ASSESSMENT The need to produce weldments with absolutely minimum shrinkage and d i s t o r t i o n for the aerodynamic v e h i c l e s i s one c r i t i c a l requirement i n the process s e l e c t i o n The second i s the need to produce J o i n t s with base metal p h y s i c a l p r o p e r t i e s The m a t e r i a l to be Joined the J o i n t type and the geometry and dimensions of the weldment are the f a c t o r s weighted i n the process s e l e c t i o n aside from economics W e l d a b l l i t y Involves the c a p a b i l i t y of the m a t e r i a l to undergo a welding procedure without defects the attainment of s a t i s f a c t o r y p r o p e r t i e s and s t a b i l i t y I n s e r v i c e and the a b i l i t y to withstand post weld thermal treatment and cryogenic or elevated temperature s e r v i c e without premature f a i l u r e W e ldabllity problems have been i d e n t i f i e d for the m a t e r i a l s involved I n these manufacturing requirements and a number of current research programs are devoted to t h e i r s o l u t i o n For example the polyphase n i c k e l base a l l o y s e x h i b i t the following w e l d a b l l i t y problems 1 Hot cracking of weld metal and/or heat a f f e c t e d zone 2 S t r a i n age or delayed c r a c k i n g during post weld s t r e s s r e l i e f s o l u t i o n heat treatment or s e r v i c e exposure 3 Response of weld to thermal treatment with r e s p e c t to p r o p e r t i e s and s t a b i l i t y k Intermediate temperature embrlttlement or the 1400 F embrittlement problem The r e s u l t of current and p r o j e c t e d i n v e s t i g a t i o n s i s expected to be a l l o y s of improved w e l d a b l l i t y b e t t e r understanding of the r o l e and improved c o n t r o l over p r i o r m a t e r i a l h i s t o r y post weld thermal treatments and improved f i l l e r wires Nevertheless f a b r i c a t o r s w i l l continue to face the problems of J o i n i n g high strength a l l o y s whose tolerance to flaws i s minimal and of obtaining maximum p o s s i b l e J o i n t p r o p e r t i e s by the choice of optimum welding conditions The c h a r a c t e r i s t i c of the p r e s e n t l y known fusion welding processes which i n d i c a t e s c a p a b i l i t y for holding c l o s e dimensional t o l e r a n c e s i s the energy input required to produce a J o i n t i n a given m a t e r i a l and thickness F i v e processes are compared for the case of butt welding 3/8 inch t h i c k p l a t e i n 06AC a l l o y s t e e l as follows Continued on next page ALTERNATE PROCESSES FLASH BUTT WELDING Code 6 02 09
-271 CHART, ^ ^ NO V3^ STATE OF THE ART ASSESSMENT, continued PROCESS E l e c t r o n Beam High Power Density TIG Conventional TIG Submerged Arc Plasma Arc J o i n t Geometry Square Butt Square Butt 90° Included Angle X 060 Land Square Butt 70 Included Angle X 3/16 Land No of Passes 1 2 4 1 Avg Energy per Pass K l l o i o u l e s / l n c h 7 6 24 8 27 6 116 6 60 4 T o t a l Energy K i l o j o u l e s / I n c h 7 6 49 6 110 2 116 6 120 9 The second c h a r a c t e r i s t i c of importance i s the a b i l i t y of the process to r e l i a b l y produce defect free welds Two processes have demonstrated t h i s c a p a b i l i t y e l e c t r o n beam and conven t l o n a l TIG welding I t i s a n t i c i p a t e d that the plasma arc which can be considered a v a r i a t i o n of the TIG process w i l l e x h i b i t s i m i l a r c a p a b i l i t y Thus the magnitude of the power density the s t a b i l i t y and c o n t r o l l a b i l i t y of the energy source and the process r e l a t e d welding environment become the c r i t i c a l c r i t e r i a The power density of the e l e c t r o n beam i s i n the order of 20 000 000 watts per square inch The LASER i s the only p r e s e n t l y known energy source that can exceed t h i s magnitude but i t s t o t a l average power i s only a small f r a c t i o n of that required The cold cathode e l e c t r o n beam should be capable of producing very high power density but i t does not appear to o f f e r any advantage as compared with the e l e c t r o n beam Consequently e l e c t r o n beam welding In hard vacuum w i l l s a t i s f y the requirements for the hypersonic c r u i s e v e h i c l e For the very large s t r u c t u r e s however the vacuum chamber dimensions w i l l Impose an economic l i m i t on the u t i l i z a t i o n of t h i s process A portable e l e c t r o n beam welder operating in the 10 to 100 micron range pr e s e n t l y being developed under Air Force auspices may overcome these l i m i t a t i o n s Two other processes merit further development for these a p p l i c a t i o n s TIG welding does because i t I s amenable to p r e c i s e c o n t r o l and because i t s s t a b l e arc energy source and low v e l o c i t y i n e r t gas s h i e l d provide a favorable welding environment I t s disadvantage i s r e l a t i v e l y low welding speed Developments i n the areas of c o n s t r i c t i n g the arc to increase i t s power density pre heating f i l l e r wire to increase deposition rate and opposed arc welding should reduce energy Input and reduce the time required to produce a very long J o i n t In heavy p l a t e Improved adaptive c o n t r o l s w i l l further Increase the process r e l i a b i l i t y Plasma arc welding re q u i r e s further development of the torch to improve r e l i a b i l i t y and to increase power density The l a t t e r w i l l e f f e c t an Increase i n penetration c a p a b i l i t y and a reduction i n energy input The c o n t r o l systems should be analyzed for p o s s i b l e improvement and adaptive c o n t r o l s developed Despite process and equipment development accidents are l i k e l y to occur i n welding very large s t r u c t u r e s which w i l l r e s u l t i n weld defects Therefore r e p a i r methods must be developed so that r e l i a b l e r e p a i r s can be made i n the various c a t e g o r i e s of m a t e r i a l s and s t r u c t u r e s each presenting s p e c i a l problems CRITICAL PROBLEMS 1 Weldability problems e x i s t i n each category of m a t e r i a l c i t e d I t i s a n t i c i p a t e d that current and projected research programs w i l l a l l e v i a t e many of these problems i n the current a l l o y s Nevertheless new a l l o y s w i l l Introduce new problems which w i l l have to be d e a l t with as they are discovered Increased emphasis upon i n v e s t i g a t i n g w e l d a b i l i t y as an i n t e g r a l part of a l l o y development would be h e l p f u l 2 Non d e s t r u c t i v e t e s t i n g methods need e v a l u a t i o n for c a p a b i l i t y to detect small flaws i n the very narrow f u l l penetration s i n g l e pass e l e c t r o n beam welds i n t h i c k s e c t i o n s Continued on next pa.&e^^_
272 CHART NO ¥>?<9 PROPOSED DEVELOPMENT PROGRAM PROGRAM I PLASMA ARC WELDING OBJECTIVE BACKGROUND To develop the plasma arc welding equipment and process to provide the c a p a b i l i t y for producing defect f r e e welds at l e a s t f i f t y f e e t long continuously I n square butt J o i n t s I n pl a t e thickness of at l e a s t one inch Joining titanium a l l o y s maraging s t e e l s n i c k e l base and high strength ferrous a l l o y s The plasma arc i s an extremely promising energy source for welding I t produces a r e l a t i v e l y high power density as compared to the TIG or MIG processes and i s capable of producing welds of r e l a t i v e l y narrow width as compared to the penetration dimension The plasma arc welding process i s a recent development therefore there i s l i t t l e i n d u s t r i a l experience from which to as s e s s i t s present c a p a b i l i t y I t has been reported to be capable of producing p o r o s i t y f r e e welds I n titanium a l l o y s and of being limited to a maximum of 1/2 inch thickness C e r t a i n l y a narrower weld w i l l e x h i b i t l e s s t r a n s v e r s e shrinkage an advantage i n welding large complex s t r u c t u r e s D i s t o r t i o n i s r e l a t e d not only to weld width but a l s o to weld geometry At present welds are wider at the top than at the root but t h i s may not be an inherent property of the energy sources The r e l i a b i l i t y and r e p r o d u c i b i l i t y of the process have been c r i t i c i z e d but t h i s i s c h a r a c t e r i s t i c of the e a r l y h i s t o r y of any of the welding processes APPROACH Phase 1 A n a l y s i s of Equipment a Analyze SQA plasma arc torch I d e n t i f y elements that l i m i t operating l i f e power den s i t y arc s t a b i l i t y r e p e a t a b i l i t y Analyze SOA c o n t r o l equipment 1 I d e n t i f y elements that require improvement 2 I d e n t i f y new c o n t r o l systems that would improve process c o n t r o l and/or r e l i a b i l i t y example c o n t r o l of torch to-work distance c o n t r o l of input gas flow r a t e as a function of measured arc voltage Phase 2 Design and Manufacture Improved Equipment Phase 3 A n a l y s i s of Process Analyze e f f e c t and l i m i t s of c o n t r o l l e d input v a r i a b l e s on process Analyze e f f e c t of uncontrolled input v a r i a b l e s gapping mismatch heat sink v a r i a t i o n s Study process i n out-of p o s i t i o n welding Determine whether pulsing the arc current i s b e n e f i c i a l I n v e s t i g a t e opposed plasma arc welding to increase thickness c a p a b i l i t y Completely Instrument a l l t e s t s and design experiments to seek methods for adaptive c o n t r o l For example with torch to-work p o s i t i o n c o n t r o l l e d does arc voltage i n c r e a s e with i n c r e a s i n g penetration and decrease with decreasing penetration? Phase 4 Process Development Determine l i m i t i n g thickness i n square butt J o i n t s i n the downhand v e r t i c a l up and ho r i z o n t a l p o s i t i o n s for both welding from one sid e and from both si d e s A f t e r r e f i n i n g process for each m a t e r i a l weld a s u f f i c i e n t number of p l a t e s to demonstrate c a p a b i l i t i e s to weld continuously for a length of 50 fe e t and to v e r i f y l i m i t s of co n t r o l l e d process v a r i a b l e s Measure transverse and l o n g i t u d i n a l shrinkage of each J o i n t and determine the r e s i d u a l s t r e s s r e s u l t i n g from the welding operation Examine J o i n t s by non d e s t r u c t i v e procedures and by tran s v e r s e and l o n g i t u d i n a l c r o s s - s e c t i o n i n g Perform t e n s i l e and f r a c t u r e toughness t e s t i n g The m a t e r i a l s to Continued on next page
273 CHART . , ^ NO V > 3 ^ PROPOSED mVELOPMElTr PROGRAM continued be Joined are 1 2 3 Titanium a l l o y s (alpha beta and beta a l l o y s ) Maraging S t e e l High strength ferrous a l l o y Nickel base p r e c i p i t a t i o n strengthening a l l o y PROGRAM I I TIG WELDING OBJECTIVE To increase the depth of penetration and welding speed c a p a b i l i t y of the TIG welding process BACKGROUND APPROACH OBJECTIVE TIG welding I s the most c o n t r o l l a b l e and most r e l i a b l e of the automatic e l e c t r i c arc welding processes However i t has been limited i n the thickness I t can penetrate I n one pass This has led to the development of grooved J o i n t s and multi pass welding T h i s technique has c e r t a i n b e n e f i t s I n that g r a i n refinement r e s u l t s from the subsequent r e l a t i v e l y low energy Input passes However the time required to complete a J o i n t Increases and the p r o b a b i l i t y of weld -defect incidence increases with the number of passes used to complete the j o i n t Furthermore prepared j o i n t s with narrow lands are much more d i f f i c u l t to f i x t u r e than are square butt j o i n t s I t i s a n t i c i p a t e d that s i n g l e pass welds in square butt j o i n t s i n heavy plate w i l l e x h i b i t l e s s d i s t o r t i o n of the weldment than w i l l m u l t i pass welds The recent development of high power density TIG welding demonstrating c a p a b i l i t y to penetrate 3/4 Inches of aluminum a l l o y s and about 5/8 inch s t e e l gives promise of a r e l i a b l e j o i n i n g process for heavy p l a t e at lower cost Phase 1 Development of Process a I n v e s t i g a t e p u l s i n g the arc current as means of c o n t r o l l i n g the l i q u i d weld metal b Develop the opposed arc process i n v e s t i g a t i n g pulsed and constant arc current c I n v e s t i g a t e means of s t i f f e n i n g arc by imposed magnetic f i e l d to reduce detrimental e f f e c t s on s t a b i l i t y due to re t u r n current path Improve method of applying ground connection i e r o l l i n g contacts located I n c o n t r o l l e d p o s i t i o n with respect to arc I n v e s t i g a t e p o s s i b i l i t y of c o n s t r i c t i n g arc by magnetic lens d I d e n t i f y equipment improvements required to Increase welding speed for example Increased esponse r a t e of arc voltage cont o i l e d head fo highe welding speed e tc Phase 2 Demonstration of Process C a p a b i l i t y Demonstrate the TIG welding process for t h i c k plate following the procedures outlined i n Phase 4 of Program No I PROGRAM I I I ELECTRON BEAM WELDING To develop the e l e c t r o n beam welding process for the welding of plate thicknesses i n excess of three inches BACKGROUND The e l e c t r o n beam process I s c h a r a c t e r i z e d by extremely high power density and seemingly unlimited penetration c a p a b i l i t y Up to now I t has been applied to producing very high q u a l i t y square butt j o i n t s i n excess of two Inches t h i c k Continued on next page
274 CHART NO HSO PROPOSED DEVELOPMENT PROGRAM, continued welds and e x h i b i t i n g an unusual degree of r e p r o d u c i b i l i t y One of the major advantages of the process I s that t r a n s v e r s e weld shrinkage i s uniform small i n dimension and p r e d i c t a b l e Angular d i s t o r t i o n i s u s u a l l y n e g l i g i b l e Thus I t i s unique among the welding processes i n i t s a b i l i t y to Joi n complex s t r u c t u r e s while maintaining f i n a l dimensional c o n t r o l T h i s appears to r e s u l t from the f a c t that energy i s t r a n s f e r r e d throughout the e n t i r e thickness of the j o i n t simultaneously as w e l l as from the weld geometry The welding operation generally takes place i n a hard vacuum a very b e n e f i c i a l atmosphere for many s t r u c t u r a l m a t e r i a l s The cost of the vacuum chamber imposes an economic l i m i t a t i o n on the s i z e of the s t r u c t u r e to be welded by t h i s process This l i m i t a t i o n may be a l l e v i a t e d by the recent development of e l e c t r o n beam welding i n the intermediate vacuum range of 10 to 100 microns and the A i r Force funded programs to develop a portable e l e c t r o n beam welding system However recent attempts to weld four inch t h i c k p l a t e s of ferrous a l l o y s have revealed the need for much deeper knowledge of the process than presently e x i s t s APPROACH Phase 1 Process Study a Instrument equipment completely to measure beam power density and d i s t r i b u t i o n a c c e l e r a t i n g voltage beam current e tc b Develop technique for taking high speed motion p i c t u r e s while welding to determine exact nature of melting l i q u i d flow and f r e e z i n g Use IR s e n s i t i v e f i l m to study energy t r a n s f e r during welding c I n v e s t i g a t e e f f e c t of r e p e t i t i v e l y pulsing between two set l e v e l s a c c e l e r a t i n g voltage beam current focus c o i l c u r r e n t d I n v e s t i g a t e most s u i t a b l e j o i n t design for welding four inch t h i c k p l a t e t i g h t square butt gapped butt prepared j o i n t Phase 2 F i l l e r - W i r e Addition The a d d i t i o n of f i l l e r wire i n the weld puddle i s common with TIG welding an inherent process requirement with MIG welding and in f r e q u e n t l y u t i l i z e d with e l e c t r o n beam welding F i l l e r wire a d d i t i v e I s necessary in welding heavy p l a t e with the f i r s t two processes because a grooved j o i n t i s necessary The ma t e r i a l removed by grooving must be f i l l e d with welding wire Frequently the composition of the welding wire i s modified as compared with the base metal De o x i d i z e r s and other scavenger agents are u s u a l l y added Some elements are Increased i n concen t r a t i o n to compensate for t h e i r l o s s during welding I n some cases very l i t t l e m o d ification from the base metal composition i s involved I n others the f i l l e r wire i s of completely d i f f e r e n t composition Examples of the l a t t e r occur when the base metal composition i s subject to hot cracking under the thermal conditions imposed by the process when d i s s i m i l a r metals are welded and the wire chemistry i s chosen to provide a gradual t r a n s i t i o n i n p h y s i c a l p r o p e r t i e s and when solute segregation (coring) degrades the weld metal c o r r o s i o n r e s i s t a n c e or response to post-weld thermal treatment Grooved j o i n t s are not required for e l e c t r o n beam welding therefore adding f i l l e r wire has not been necessary Furthermore i n t e r d e n d r i t i c spacing i s s u b s t a n t i a l l y smaller in e l e c t r o n beam welds and macro segregation of solute i s probably minimized due to the Inhere n t l y low energy input of the process Consequently e l e c t r o n beam uelds have frequently displayed improved p h y s i c a l p r o p e r t i e s as compared with welds produced by TIG or MIG welding Wire feed has been u t i l i z e d to c o r r e c t an under f i l l c o n d ition r e s u l t i n g from l e s s than optimum f i t up of j o i n t s I n such cases the wire was u s u a l l y of base metal composition Since the AARP requirement I s for welded j o i n t s e x h i b i t i n g base metal p r o p e r t i e s i t may be necessary to modify base metal chemistry i n the weld metal produced by e l e c t r o n beam welding i n c e r t a i n s p e c i f i c a l l o y systems I t must then be questioned as to whether conventional f i l l e r wire a d d i t i o n techniques w i l l r e s u l t i n adequate mixing of the molten wire with the molten weld metal while e l e c t r o n beam welding heavy p l a t e A l t e r n a t i v e techniques such as preplaclng a t h i n s t r i p between the butting s u r f a c e s or i t may be necessary to back up the weld j o i n t with a narrow s t r i p of adjusted chemistry An e f f e c t i v e method of a d j u s t i n g base metal chemistry Continued on next page
275 NO T30 PROPOSED IKVELOPMKOT PROGRAM, continued must be developed i n the event that modification to wide metal chemistry i s found necessary during performance of the next phase This study w i l l be s i m p l i f i e d by choosing a f i l l e r metal and base metal such that one w i l l d i s s o l v e i n the other and for which segregation i s r e a d i l y observed by etching techniques Copper f i l l e d metal and mild s t e e l base metal exemplify t h i s s i t u a t i o n a Use two inch t h i c k p l a t e s of selected base metal machined for square butt J o i n t s b Add f i l l e r wire while welding and determine extent of mixing of f i l l e r wire with base metal - 1 Add f i l l e r wire ahead of beam 2 Add f i l l e r wire behind beam 3 Determine wire diameter and feed rate as a function of other welding parameters c Determine degree of mixing with pre-place shim between butting surfaces Determine i f shim thickness i s r e l a t e d to degree of mixing d Determine whether complete mixing can be accomplished by placing a narrow back up plate below butt Jo i n t or a scab s t r i p on top of the weld Phase 3 Welded J o i n t Evaluation Demonstrate the E l e c t r o n Beam Welding Process for four inch t h i c k plate following the procedures outlined i n Program Mo I Phase 4 Non-destructive Testing Evaluate SOA non-destructive te s t i n g methods for welds of high depth to width r a t i o i n heavy plate PROGRAM IV WELDING TECHNIQUE OTTIMIZATION OBJECTIVE To optimize fusion welding process parameters for butt welding s e v e r a l high strength materials Optimization c r i t e r i a are to obtain ph y s i c a l properties i n the weldment equal to those of the unwelded base material and predictable f i n a l dimensions of the weldment BACKGROUND A fusion weld can be considered a continuous cas t i n g i n which the members being Joined act as the mold I t may be expected therefore that the knowledge gained from cas t i n g p r a c t i c e may be u t i l i z e d to avoid defects i n the weld metal Unlike a casting however the weld metal must be Intimately Joined to the mold The base metal surrounding the fused volume which conatltues the mold undergoes rapid heating and cooling c y c l e s and i s subject to steep thermal gradients during the s o l i d i f i c a t i o n and cooling of the c a s t zone Therefore complex m e t a l l u r g i c a l reactions occur i n the presence of thermally induced s t r e s s and frequently the physical properties of t h i s heat affected zone are ijupalred and damaging flaws are Introduced Applications of m e t a l l u r g i c a l p r i n c i p l e s and knowledge gained from heat treating p r a c t i c e would be required to optimize conditions i n the heat affected zone I t i s apparent therefore that welding technique can greatly influence the phy s i c a l properties of a fusion welded Jo i n t I n high strength material Factors such as welding speed energy input and geometry of fused area a f f e c t the properties of the weldment Transverse shrinkage i s proportional to width of fusion zone d i s t o r t i o n to asymmetry i n i t s geometry D i s t o r t i o n i s also r e l a t e d to the t o t a l energy transferred to the members to produce the fusion weld In order to thoroughly explore a wide range of welding conditions the fusion welding process oust not i t s e l f l i m i t the parameter values that can be investigated For example the welding speed i n TIG welding i s limited by arc voltage control Continued on next page
CHART 276 PROPOSED DEVELOPMENT PROGRAM continued response and s t a b i l i t y and by arc s t i f f n e s s E l e c t r o n beam welding i s the one process that permits welding with a v i r t u a l l y unlimited range of parameter values A l l f u s i o n welding i n t h i s program therefore w i l l be accomplished by the e l e c t r o n beam process and i n a hard vacuum to eliminate contamination by the ambient environment as a factor I t i s a n t i c i p a t e d that the knowledge gained from t h i s program could be applied to Improving a l l the fusion welding processes APPROACH Phase 1 Design of Experiments The o b j e c t i v e s are to weld a s i n g l e thickness of each of f i v e r e p r e s e n t a t i v e a l l o y s u t i l i z i n g a wide range of conditions so that optimum process parameters can be determined The EB process parameters to be v a r i e d include welding speed beam power beam power den s i t y and focus of beam f o c a l point with r e s p e c t to surface of work piece The magnitude of the p o s s i b l e combinations can be appreciated from the fa c t that i n a recent i n v e s t i g a t i o n v i s u a l l y acceptable welds were produced i n one-half inch t h i c k 201A-T651 aluminum a l l o y at welding speeds ranging from 10 to 250 1pm Ad d i t i o n a l parameters are beam oscillation-magnitude frequency and pattern f i l l e r wire a d d i t i o n and preheat The p h y s i c a l p r o p e r t i e s to be r e l a t e d to welding techniques are t e n s i l e y i e l d and ultimate strengths f r a c t u r e toughness and fatigue strength I n ad d i t i o n r e s i d u a l s t r e s s and shrinkage and d i s t o r t i o n should be measured The experimental procedure w i l l have to be c a r e f u l l y designed to avoid an i n f i n i t e l y large number of experiments S t a t i s t i c a l methods and new t e s t i n g methods such as the V a r e s t r a l n t T e s t should be u t i l i z e d to minimize the dimensions of the task without s a c r i f i c i n g the v a l i d i t y of the r e s u l t s Phase 2 Welding T e s t s Following the experimental procedures designed in Phase 1 weld one inch t h i c k t e s t specimens of the following m a t e r i a l s Alpha beta titanium a l l o y beta titanium a l l o y maraging s t e e l high strength ferrous a l l o y n i c k e l base p r e c i p i t a t i o n strengthened a l l o y Post weld heat t r e a t specimens where app l i c a b l e Perform non d e s t r u c t i v e t e s t i n g metallographlc examinations and p h y s i c a l t e s t i n g Phase 3 A n a l y s i s of T e s t s C o r r e l a t e p h y s i c a l p r o p e r t i e s with welding parameters and s e l e c t optimum welding technique for each m a t e r i a l E x t r a p o l a t e to 1/2 and 1-1/2 Inch t h i c k n e s s e s and perform a l i m i t e d but s u f f i c i e n t number of welding and property t e s t s to v e r i f y that optimization has been achieved OBJECTIVE INSPECTION AND EVALUATION TECHNIQUE SUPPLEMENT Ins p e c t i o n of fusion welds I n high performance Iron n i c k e l and titanium base a l l o y s made by plasma a r c TIG and e l e c t r o n beam welding BACKGROUND State of the a r t i n s p e c t i o n techniques e x i s t that s a t i s f y the current requirement for c h a r a c t e r i z i n g q u a l i t y Radiographic techniques and surface i n s p e c t i o n with magnetic p a r t i c l e s or penetrants have s a t i s f i e d most requirements when proper planning and Inspector t r a i n i n g have been employed With s t e e l and aluminum weldments u l t r a s o n i c techniques have been a valuable supplement with a better c a p a b i l i t y of detecting subsurface c r a c k l i k e defects None of the e x i s t i n g techniques are adequate I f m a t e r i a l s of low d u c t i l i t y and low notch toughness are made at s t r e s s l e v e l s near t h e i r design l i m i t s Also the weldments i n high performance a l l o y s are not g e n e r a l l y amenable to u l t r a s o n i c i n s p e c t i o n Continued on next page
CHART 277 INSPECTION AND EVALUATION TECHNIQUE SUPPLEMENT, continued C u r r e n t l y each heat of high-strength high performance a l l o y must be q u a l i f i e d by a f u n c t i o n a l constrained w e l d a b l l l t y t e s t A quicker and more economical e v a l u a t i o n technique I s needed to p r e d i c t w e l d a b l l l t y E l e c t r o n beam welding I s a new method I n the commercial sense and has not been adequately studied and c h a r a c t e r i z e d to as s e s s the e f f e c t i v e n e s s of SOA Inspection methods E x i s t i n g techniques are s a t i s f a c t o r y f o r most weld Inspection but there i s a need for an Inspection technique to replace current f i l m radiography In r a d i a t i o n safe exposure c u b i c l e For large o b j e c t s such as large m i s s i l e chambers and tankage a more rapid and lower cost technique I s needed for on the flo o r Inspection of welds APPROACH 1 Wel d a b l l l t y search for the parameters that contribute to w e l d a b l l l t y and design one or more techniques that can I n f e r the f u n c t i o n a l c a p a b i l i t i e s of the m a t e r i a l to be welded under constrained conditions 2 Conduct an i n depth study of the f a i l u r e modes of e l e c t r o n beam welds i n a v a r i e t y of a l l o y s and J o i n t designs S e l e c t candidate and a l t e r n a t e techniques and evaluate c a p a b i l i t i e s and l i m i t a t i o n s for each type weld defect 3 Search out and evaluate new and d i f f e r e n t u l t r a s o n i c techniques that w i l l not be adversely handicapped by the high attenuation and large weld/parent metal mismatch c h a r a c t e r i s t i c of high performance a l l o y s Examples of new and d i f f e r e n t techniques are the d e l t a and Isometric approaches now being studied
278 PRIORITY RATING WORKSHEET CHART P R O a R A M P A C T o a s . PROGRAM PROBABIL ITY OF S U C C E S S ⢠D D ⢠LOW a >C n { ( ⢠MODeRATC s ⢠)tf ⢠i n HISH 8 C R I T I C A L P R O B L E M S TO B E SOLVED ⢠⢠⢠⢠F tVV /NOT TOO D I F F I C U L T Z X J O O K SOMe / O I P F C C U U T 9 ⢠⢠>( ⢠M A N Y / VERY DIFFICULT 6 P R O C e S S G R O W T H B O T E N T I A L ⢠⢠D O LITTLE OR UNDCFINABLE O ft K )Q K ttB<»H«*BLe PorBMTIAL 4 APPLICATIONS OTHER. THAN AIR R>RC£ ⢠⢠⢠⢠NONe o ⢠n a n S O M E 4 X U K W . M A N Y d N E C E S S I T Y FOR AIR FORCE F U N D I N S ⢠⢠⢠⢠LOW Hifix iNtttSxav/'cnieA fiovr C F F P A T 4. >S Vl )fi ixoixttAn - a n e eratr emea. 'Sousoea s ⢠⢠⢠⢠exeu is iye Aiit FoAet F U M P N A UKEL<4 n. N E E D F A C T O R S Pa S Y S T E M S P R O B A B I L I T Y HiaH PSOBABIL ITY 12 FAIR P R O B A B I L I T Y 8 LOW P R O B A B I L I T Y <f COMPONENT C R I T l C A L I T Y VeRY Hl^-H n HIAH 9 FA IR 6 L O W 3 FREQUCNCV OF REQUIREMENT IM S Y S T E M mne THAN 3 CoMPaXeuTS 3 £ 3 CeMPeMEMTS 2 S INf lLC CeMPONENT I OEStSN A L T E R M A T E S No ALreBNATE R u e s E E N f O N C AUTenMATC 6 S E V E R A L A L T E R U A T E Q 3 M A T E R I A L S IMPLICATION New MATSKinL pev£u>F»ie»iT e e a o « MltTCCIAL IMFAOVEMCNT Rf lS P 4 NO PRoBueM F o f t t s e e u o PROGRAM I I I C . S e ' 8 3S 9 33 33 AARP RA>N seo«es RAW s c o o e s F O R EACH COMPOMCWT M TABLES AT E w r o r PAUei ISeFocT WITH B a m T«>rnLS E N T E R C P IN ^ U M M A S V W i f ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠c CALCULATE P R I O R I T Y . STEP I CIRCLE HIGHEST AARP RAW SCORE n a STEP 2 IN EACH OTHER SV8T6M CIRCLE NEXT HIQMEST SCORE IF WITHIM i»- POIMTS OF TOP SCORC n 33 NUMBER OF SysTCMS HidlH LOW STEP 3 CIRCLE FREOOENCY DISTRIBUTION FACTOR f" NUMQen. ov sysTSH* Hiait I SORMMU N U M B C R . OF S Y S T E M S LOW I Z on MOM 1 0 1 a 1 4 1 1 1 3 1 H 12. 1 4 BELOWi f 3 Z ¥6 i P « O ^ R ^ n » f = ^ ^ ^ ^ TOTAL- 7A M. J f 9 PRIORITY CE)
279 TITLE DIFFUSION BONDING OF BERYLLIUM AND BERYLLIUM ALLOYS CHART NO PRIORITY RELATED CAMR C H A R T S , 7 0 / . 7 a V MANUFACTURING REQUIREMENT Provide low weight high s t i f f n e s s multi-walled f l a t and curved panels for s p a c e c r a f t bulk heads decks e x t e r n a l h u l l s and f o r S o l a r C o l l e c t o r Surfaces Multi-walled panels are a l s o d e s i r a b l e for drag entry v e h i c l e l i f t and c o n t r o l surface r i g i d s k i n s and substructure Gauges range from f o i l thicknesses to 0 075 inch sheet Heavier gauges could be used for space r a d i a t o r v e h i c l e e x t e r i o r s u r f a c e s to which cooling passages are to be bonded Construction r e q u i r e s honeycomb sandwich t r u s s g r i d sandwich and s t i f f e n e d sheet Components and v e h i c l e s i n nearly a l l i n s t a n c e s are q u i t e large ( s p a c e c r a f t h u l l up to 20 f t diameter x 40 f t long s o l a r c o l l e c t o r up to 60 f t diameter etc ) i n d i c a t i n g probable d e s i r e to manufacture large panels to minimize J o i n t s so as not to s a c r i f i c e I n t r i n s i c weight advantage from use of beryl l i u m AARP REFERENCES c r-u.^. 216 288 B Chart. 107d 108a 109b I l i a b 134a 176 P*n/P^ rhnrt. J o i n i n g No 5 APPLICABLE PROCESS Code CREEP CONTROLLED DIFFUSION BONDING 6 09 02 STATE OF THE ART ASSESSMENT B e r y l l i u m sheet and pressed block have been d i f f u s i o n bonded by s e v e r a l d i f f e r e n t methods 1 e press spot f r i c t i o n y i e l d strength c o n t r o l l e d and creep c o n t r o l l e d techniques I n v e s t i g a t i o n s have been conducted using v a r i o u s m e t a l l i c i n t e r f a c e m a t e r i a l s both as f o i l s and as p l a t i n g s Although information i s s c a r c e and t e s t r e s u l t s s c a t t e r e d J o i n t strengths up to 957, of parent block m a t e r i a l have been reported R e s u l t s on c r o s s r o l l e d sheet have not been g e n e r a l l y as good and t h i s I s a t t r i b u t e d to the a n i s o t r o p i c nature of wrought beryllium and to degradation of mechanical p r o p e r t i e s by the thermal c y c l e Delamlnation p r e s e n t l y l i m i t s the strength of lap shear J o i n t s to about 20 000 p s i which i s considerably lower than the t h e o r e t i c a l shear strength of the m a t e r i a l However ingot sheet which I s r e l a t i v e l y new e x h i b i t s d u c t i l i t y appreciably better than powder b i l l e t sheet although mechanical p r o p e r t i e s are considerably lower The bonding process i s f u r t h e r l i m i t e d by the oxide f i l m inherent with b e r y l l i u m and s u c c e s s f u l J o i n t s have been made only by exhaustive cleaning and where s u f f i c i e n t surface move- ment occurs during Joining to d i s p e r s e the surface oxide With b e r y l l i u m products c o s t i n g as they do a d d i t i o n a l high c o s t s for removal of oxide f i l m s followed by bonding i n i n e r t atmospheres or vacuum w i l l make be r y l l i u m s t r u c t u r e s l e s s competicive with those made from other aerospace m a t e r i a l s E f f o r t s are therefore being d i r e c t e d to applying s u f f i c i e n t load and energy to deform the s u r f a c e s without g e t t i n g the temperatures high enough to cause r e c r y s t a l l l z a t l o n of the sheet thus bringing the p r o p e r t i e s back to those of HP block T h i s means st a y i n g below 1950 F and s t i l l g e t t i n g enough a c t i v a t i o n energy i n t o the surface to cause s u f f i c i e n t l y r a p i d d i f f u s i o n R o l l d l f f j ^ s i o n bonding s t u d i e s are beginning with deformation l i m i t s and compatible mandrel m a t e r i a l s that can be e f f i c i e n t l y removed E l e c t r i c blanket and press bonding have been given l i m i t e d study The work with p l a t i n g s and I n t e r f a c e f o i l s needs to be a c c e l e r a t e d A l Zn and Sn f a i l to form a m e t a l l i c bond while Cu and Ag d i f f u s e to form i n t e r s i e t a l l l c compounds e x h i b i t i n g b r i t t l e behavior Continued on next page ALTERNATE PROCESSES YIELD STRENGTH COMIROLLED DIFFUSION BONDING Code 6 09 01
280 STATE OF THE ART ASSESSMENT continued CHART , ^ , NO V3/ The foregoing does not seem to apply to a l l o y s such as Be 38A1 but no d i f f u s i o n bonding work of any Importance has been reported Here the problem for sheet at l e a s t has been due to the u n a v a i l a b i l i t y of s i z e s large enough to I n t e r e s t designers T h i s r e s t r i c t i o n i s due to the producer s d e s i r e to assure complete p r o d u c i b l l l t y before larger s i z e s are offered Since i t has been demonstrated that t h i s a l l o y can be f u sion and r e s i s t a n c e welded as w e l l as brazed d i f f u s i o n bonding t e s t s should r e s u l t I n equally s a t i s f a c t o r y r e s u l t s and such s t u d i e s are needed Information developed for oxide f i l m removal for d i f f u s i o n bonding would conversely be a p p l i c a b l e to r e s i s t a n c e welding Appropriate modulation of electrode force and current magnl tude has shown sound crack free-spot welds but q u a l i t y has been i n c o n s i s t e n t due to the d i f f i c u l t y i n r e l i a b l y removing surface oxide CRITICAL PROBLEMS 1 The anistropy of b e r y l l i u m sheet which leads to a tendency to delaminate under high pressures 2 F o i l thickness down to 0 002 inch have been produced i n l i m i t e d q u a n t i t i e s An a b i l i t y to produce q u a l i t y f o i l and i n turn to convert f o i l to honeycomb core I s needed 3 E f f i c i e n t means to remove the oxide f i l m from su r f a c e s to be joined are required or con versely, to study the k i n e t i c s of the bonding process to a point where the oxide f i l m problem may be overcome without r e s o r t i n g to c o s t l y c l e a n i n g processes 4 Adequate assurance that present NDT methods w i l l d etect unbonded or p a r t i a l l y bonded surfaces. PROPOSED DEVELOPMENT PROGRAM OBJECTIVE APPROACH To study b a s i c d i f f u s i o n bonding parameters for beryllium and b e r y l l i u m a l l o y s and to develop j o i n t strength data w i t h i n the l i m i t a t i o n s of the parent m a t e r i a l T h i s program would lay the groundwork for the time when improved m a t e r i a l i s a v a i l a b l e and would stimulate the needed work i n parent metal improvement 1 A program i s recommended which w i l l explore the p o s s i b l e parameters applying to d i f f u s i o n bonding for the various form and grades of b e r y l l i u m and i t s a l l o y s T h i s should Include HP block c r o s s r o l l e d sheet Ingot sheet the l a t e s t high strength sheet and a l l o y s i n block and sheet and honeycomb core Phase I Bonding Parameters a A study of the time temperature pressure r e l a t i o n s h i p s to j o i n t strengths i n c l u d i n g the e f f e c t of deformation on oxide d i s p e r s a l Optimum combination of times temperatures and pressures should be e l e c t e d for both honeycomb s t r u c t u r e s which are crushable and those s t r u c t u r e s which are not crushable b A study of surface cleaning methods including mechanical chemical e l e c t r o chemical and u l t r a s o n i c c A study of the reformation of surface oxides under conditions of atmospheric exposure at room temperature and exposure to v a r i o u s p o t e n t i a l bonding atmos pheres at temperatures up to 1400 F for times up to four hours d An e v a l u a t i o n of a l t e r n a t e processes such as the r e s i s t a n c e upsetting and gathering technlquee s u c c e s s f u l l y used with titanium a l l o y s and the s t r a i g h t r e s i s t a n c e upset under load techniques both as applied to heavy s e c t i o n s Phase I I Process A p p l i c a t i o n a Phase I I programs s h a l l include an e v a l u a t i o n of known processes such as y i e l d creep e l e c t r i c blanket press etc based on the information evolved i n Phase I (a) through (d) b F a b r i c a t i o n and t e s t i n g of prototype assemblies 2 Concurrently with a l l the above i s the need to upgrade the c a p a b i l i t i e s of producer to produce larger more r e l i a b l e products p a r t i c u l a r l y i n the sheet and f o i l gauges I n f a c t b a s i c l i m i t a t i o n s i n raw form processing must be studied to detect any d e t e r r e n t to large p o t e n t i a l use of these products
281 PRIORITY RATING WORKSHEET P R O f i R A M PACTQgft, PR06RAM PROBABIL ITY OF S U C C E S S o tow ⢠MooenATC % HiaH CRIT ICAL P R O B L E M S TO B E S0tVâ¬O ⢠F t V ^ / N O T TOO DIFFUTULT ft S O M E / D I F F I C U L T D M A N Y / VERY DIFFICULT P R O C E S S fiROWTH P O T E N T I A L 0< LITTLE OR I INOEFINABLE ⢠eecOGHIlhaiB poreMTIAL APPLICATIONS OTHER. Tt4AN AIR PORCC ⢠NONE ⢠SOME ^ MAMV N E C E S S I T Y FOR AIR FORCE FUNDIMQ n LOW HisH iiititSTiiv/'erHCA GOVT CFFecr 4- JBi MeoWATB - soi*e Brtax ernes, â¢seuaoeg e ⢠E K c u i s i i ^ e A IR Foftet F U M P M A U K E L V 12. 2 5 8 2 S s o ⢠o 4 NEED FACTORS S Y S T E M S P R O B A B I L I T Y H i a H P R O B A B I L I T Y FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T l C A L I T Y VERY HICH H I A H FAIR L e w F R E Q U E N C Y OF REQUIREMENT IN ^ Y ^ T E M MORE THAN 3 C«)MP»»'eHT9 2. 3 COMPeMEMTS S IMPLE C e M P M E N T DESISN A L T E R N A T E S No ALTERNATE R M E e e E N ONE ALTERMATe S E V E R A L A L T E R M A T E C MATERIALS IMPLICAriON New MATERIAL peyElOf^MENT RC« O nWreClAL IMP(U>VEM£WT E E f i i P NO PROOUEM FoRC^ee id 12 8 4 12 9 6 3 3 2 1 6 3 6 4 o CALCULATE P R I O R I T Y . STEP I STEP Z CHART S R A W SCOUS F O R EACri R E F C K E M O P CoMPCMCtfT M T A B L E S A T t W D O F PAUEL BEPatT W I T H B A M TeTALS ENTEEEV IN ^UMMAItV AT eiSMT AARP RA^i seoses S Y S T E M S Z ] [ i n I H Z ] ⢠⢠] ⢠⢠⢠⢠] ⢠⢠⢠⢠⢠⢠⢠⢠⢠] ⢠⢠⢠[ : CIRCLE HIGHesT AARP RAW SCORE IN EACH OTHER SVeTCM CIRCLE NEXT HIOHeST IF WITHIN if POINTS OF TOP SCORE n 2 LflML/ 3 scoee NUM&ER OF SVSTEMS HlOH STEP 3 CIRCLE FREOUENCY DISTRIBUTION FACTOR f BELOW. I 2 3aRMMtS N U M S E R OF S Y S T E M S LOW 0 I 2 e R M o O E 1 0 1 2 \ 4 1 1 1 3 t £ 1 4 I? i l l TOTAL PRIORITY
282 TITLE DIFFUSION BONDING OF NICKEL-BASE SUPERALLOYS SUPERALLOYS AND CHROMIUM-BASE ALLOYS COBALT-BASE CHART RELATED PRIORITY lABTSi MANUFACTURING REQUIREMENT Honeycomb sandwich t r u s s core sandwich and s t i f f e n e d s k i n panels are needed from one or more of the n i c k e l - b a s e cobalt-base superalloys or chromium-base a l l o y s Curved and f l a t panels can be up to 6 f e e t x 12 f e e t Sheet and p l a t e gauges 0 010 Inch to 0 25 inch f o i l gauges 0 001 inch to 0 005 inch Bulkheads frames f i t t i n g s up to 6 feet made from forglngs e x t r u s i o n s bar and sheets 0 020 inch to 0 12 Inch Double walled ducting up to 5 f e e t diameter with w a l l t h i c k n e s s e s 0 040 inch to 0 25 inch Heat s h i e l d panels 1 foot square are required with faces 0 006 inch to 0 010 inch and panel t h i c k n e s s e s 1/8 inch to 1/4 inch 2300 F A l l r e q u i r e subsequent coating for o x i d a t i o n r e s i s t a n c e Maximum s e r v i c e temperature AARP REFERENCES E Chort. 63. 64. 65. 66. 93. 94. 95. 116. 272 B Chort. 30b c 31b c 41b c 42b c 50a b 51b 122c PSFVPS Charts. APPLICABLE PROCESS YIELD STRENGTH COlflROLLED DIFFUSION BONDING (using high pressure and short time) or CREEP CONTROLLED DIFFUSION BONDING (using low pressure and long time) Code 6 09 01 6 09 02 STATE OF THE ART ASSESSMENT The p r e c i p i t a t i o n strengthening n i c k e l - b a s e s u p e r a l l o y s Rene 41 Inconel 718 and Inconel 750 etc represent some of the most d i f f i c u l t types of m a t e r i a l s for Joining by welding brazing or by d i f f u s i o n bonding A l i m i t e d amount of work conducted to date has demonstrated the f e a s i b i l i t y of d i f f u s i o n bonding these materlalSj as w e l l as the need for exacting c o n t r o l of the bonding parameters and atmosphere environment E u t e c t i c bonding appears to provide an immediate s o l u t i o n to the problem of Joining these m a t e r i a l s with the low deformation s t a t i c bonding processes Cobalt base a l l o y s and TD n i c k e l , Including i t s higher strength a l l o y modif ications^, J o i n r e a d i l y using c u r r e n t s t a t e of the a r t methods Attempts to r o l l d i f f u s i o n bond some of the aluminum and titanium c o n t a i n i n g m a t e r i a l s have been unsuccessful to date due to contamination of the s u r f a c e s to be bonded during heating to bonding temperature The aluminum and titanium a l l o y i n g elements getter the contaminants forming t i g h t l y adherent f i l m s that prevent bonding The development of ch omlum base a l l o y s has progressed to a point where s e v e r a l preliminary compositions show promise but l i t t l e or no d i f f u s i o n bonding work has been attempted CRITICAL PROBLEMS 1 More a l l o y development for chromium-base a l l o y s i s required Work i s required to extend sheet widths of TD a l l o y s from i t s present 12 inch to 36 inch and f o i l development i s required for honeycomb core 2 Cleaning of d e t a i l p a r t s and t o o l i n g p r i o r to bonding i s a c r i t i c a l problem due to the very high degree of c l e a n l i n e s s required as compared with the c u r r e n t s t a t e of the a r t 3 Lay up and purging procedures w i l l need to be g r e a t l y Improved to minimize other p o t e n t i a l sources of contamination 4 R o l l bonding press bonding blanket bonding or gas-pressure bonding are each needed for s p e c i f i c geometries for a c c e s s of t o o l i n g and f o r c o n t r o l of pressure to prevent crushing or e x c e s s i v e tolerance v a r i a t i o n 5 Development of tooling and r e t o r t m a t e r i a l s i s a problem because of oxidation excess tooling deformation and tooling removal ALTERNATE PROCESSES NONE Code
-283 CHART PROPOSED DEVELOPMENT PROGRAM OBJECTIVE BACKGROUND APPROACH To develop p r o c e s s i n g d a t a on the d i f f u s i o n bonding o f n i c k e l base s u p e i a l l o y s c o b a l t base s u p e i a l l o y s and chromium base a l l o y s e s t a b l i s h i n g the e x t e n t t o which t h e y can be bonded by b o t h y i e l d s t r e n g t h and creep c o n t r o l l e d processes The d i f f i c u l t y I n p r o d u c i n g chromium-base a l l o y s t h e i r i n h e r e n t p h y s i c a l and mechanical p r o p e r t i e s i n c l u d i n g b r i t t l e n e s s o f d i f f u s i o n bonded j o i n t s which can become more severe i n s e r v i c e i s viewed as a d e t e r r e n t t o t h e i r use compared t o a l t e r n a t e m a t e r i a l s More i n f o r m a t i o n on the m e r i t s and disadvantages o f i n d i v i d u a l t e chniques i s d e s i r e d i n c l u d i n g f a b r i c a t i o n o f subscale components i n c o r p o r a t i n g t y p i c a l d e s i g n c o m p l e x i t i e s such as edge members and l o c a l attachment p o i n t s E f f o r t should be paced by how p r o m i s i n g chromium base r e f r a c t o r y a l l o y components prove t o be i n r e l a t i o n t o a l t e r n a t e m a t e r i a l s A number o f n i c k e l - b a s e s u p e r a l l o y s and c o b a l t - b a s e s u p e r a l l o y s are a v a i l a b l e w i l l be developed which cannot e f f i c i e n t l y be Joined by w e l d i n g and r e q u i r e d c o n f i g u r a t i o n and s e r v i c e temperatures do n o t p e r m i t b r a z i n g or mechanical f a s t e n i n g D i f f u s i o n bonding by v a r i o u s procedures s i m i l a r t o those being developed f o r t i t a n i u m are needed R o l l bonding press bonding b l a n k e t bonding and gas pressure bonding methods are r e q u i r e d t o produce the v a r i e t y o f shapes r e q u i r e d 1 Determine the f a c t o r s o f s u r f a c e c o n d i t i o n i n g p u r g i n g and temperature time p r e s s u r e r e l a t i o n s h i p s which w i l l produce p a r e n t m e t a l s t r e n g t h s i n J o i n t s o f Rene A l I n c o n e l 718 I d Nl-Cr o t h e r n i c k e l base s u p e r a l l o y s c o b a l t base s u p e r a l l o y s and chromium base a l l o y s 2 Determine the f e a s i b i l i t y o f d i f f u s i o n bonding t h i c k and t h i n gauge m a t e r i a l s and p r o d u c i n g s t r u c t u r a l assemblies by the r o l l d i f f u s i o n bonding pressures 3 Determine r o l l i n g temperatures m i l l r e d u c t i o n p u r g i n g procedures s u r f a c e p r e p a r a t i o n r equirements f o r r o l l d i f f u s i o n bonding c l e a n i n g and 4 E s t a b l i s h r e t o r t and t o o l i n g m a t e r i a l s t h a t are c o m p a t i b l e w i t h the s p e c i f i c a l l o y and r o l l bonding process and can be removed by mechanical or chemical means Mandrels of low I n i t i a l c o s t and low removal c o s t should be emphasized 5 Determine f i t - u p t o l e r a n c e s and s u r f a c e f i n i s h e s necessary t o produce the f i n a l p a r t c o n f i g u r a t i o n and dimensions 6 Determine t h e f e a s i b i l i t y o f d i f f u s i o n bonding t h i c k and t h i n gauge m a t e r i a l s and p r o d u c i n g s t r u c t u r a l assemblies by the e l e c t r i c b l a n k e t bonding process 7 Determine the f e a s i b i l i t y o f p r o d u c i n g c l o s e t o l e r a n c e s t r u c t u r a l shapes w i t h o u t d e f o r m a t i o n by the creep c o n t r o l l e d processes T h i s process c o u l d combine l o c a l i z e d J o i n i n g processes such as spot d i f f u s i o n bonding and gas pressure or press bonding techniques depending upon c o n f i g u r a t i o n o f the p a r t J o i n t d e s i g n and a c c e s s i b i l i t y 8 Develop equipment and t o o l i n g m a t e r i a l s which w i l l p r o v i d e r e l i a b l e atmospheric c o n t r o l d u r i n g bonding T h i s i n c l u d e s chambers f o r l o c a l i z e d bonding and e n c a p s u l a t i n g ! m a t e r i a l s and t o o l i n g capable o f h i g h temperatures p r e s s u r e s and long times r e q u i r e d f o r creep bonding processes 9 Determine the e f f e c t of creep c o n t r o l l e d bonding processes I n v o l v i n g low pre s s u r e s and long time a t temperature on parent m e t a l p r o p e r t i e s and j o i n t s t r e n g t h and the use o f i n t e r m e d i a t e m a t e r i a l s t o reduce bonding pressure and temperature 10 Develop p r o t e c t i v e atmosphere chambers t h a t are adaptable t o l o c a l i z e d bonding processes
284 PRIORITY RATING WORKSHEET CHART NO P R 0 6 R A M PROBABIL ITY OF S U C C E S S ⢠LOW Z. ⢠MOoeRATE 5 % HieH 8 C R I T I C A L P R O B L E M S TO B E SOLVED n FEVV/NOT TOO DIFFWULT 2. ⢠S O M E / D I F F I C U L T S X M A N Y / VERY D IFF ICULT 8 P R O C E S S G R O W T H P O T E N T I A L ⢠L ITTLE OR UNDEFINAOLE O ti KEC06NIIABLE PoreUTIAL 4 A P P L I C A T I O N S OTHER THAN AIR FORCE ⢠NONE O >$ SOME 4 a MANY e N E C E S S I T Y F O R A I R F O R C E F U N D I M G ⢠LOW HisH wpusTKV/'in-Htft G w r CFFP^T <f ^ M»oeilAT6 - Seine Bremx erttce. â¢Sooeees e a ttccLusive A IR poiut FUUVU& U K E L W 12. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HiaH PTJOBABILlTY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y VERY HId-H H I « H FAIR L o w F R E a U E N C y OF REQUIREMENT IM « V $ T E M MOns THAN 3 CCMPeHeuTS 2. 3 ceMpeUEnrs S I N f l L E CeMPeNCNT DESt&N A L T E R N A T E S No AUTEBNATe R w e e E e N ONE A L T E B N A t e S E V E R A L ALTERIJATe« M A T E R I A L S IMPLICATION New MATEfciflL pe.v£u)j>»ie»iT cea o MATtClAL IMPftOVEMCNT RElSl D NO P R o a L E M f o f t t s e e i a IZ 8 4 IZ 9 3 3 2 I <J 6 3 6 4 o CALCULATE PRIORITY S T E P I C IRCLE HIGHEST A A R P RAW S C O R E e 6 17, RAW Scopes Foft E A C H REFceeiKW COMFONCMT IN TA&Li:$ AT tNB OF PAMEl RtPfltT VXITH llAM T O T A L S ENTeRrp IN A T eiSHT 5 / S T E P 2 S T E P 3 IN EACH dTHER S Y S T E M IF WITHIW t>t P O I M T S NUMBER OF SVSTEMS C I R C L E H ldH C I R C L E NEXT H I G H E S T O F T O P S C O R E n * ^ L O W C F R E O U E N C Y D ISTRIBUTION F A C T O R MUMQER. sysrews rtisH S C O R E 3 SK Mete NUMeeR. OF S Y S T E M S LOV/ 0 1 2 R. Moee 1 0 1 a ( T O 1 1 1 3 1 *f 1 z 1 «f 1 «f AARP RA>M SCOWS ⢠⢠⢠⢠i r n II 1 r n n n r \ \ \ ⢠⢠⢠⢠II 1 I L J r n n n r i r j ⢠⢠⢠⢠⢠1 II II II II 1Ì l U ⢠⢠⢠L i n ⢠⢠⢠⢠II 1 ⢠⢠⢠L II 1 II 1 ⢠⢠⢠⢠II 1 ⢠⢠⢠⢠II 1 II 1 ⢠⢠⢠⢠⢠n c z i a n r n r i n a n n ⢠TOTAL PRIORITY
285 TITLE DIFFUSION BONDING OF MOLYBDENUM ALLOY SHEET PLATE AND HONEYCOMB ASSEMBLIES CHART N O PRIORITY RELATED CAMI ARTS MANUFACTURING REQUIREMENT To J o i n by d i f f u s i o n bonding honeycomb core t o faces and edge members t y p i c a l sheet m e t a l d e t a i l s such as p l a i n and c o r r u g a t e d s k i n s r i b s s t l f f e n e r s and sm a l l r a d i u s c o n i c s e c t i o n s o f gauges from 0 010 Inch t o 0 100 Inch h e a v i e r p l a t e gauges t o produce l a r g e complex f i t t i n g s j o i n e d t o s k i n and frame s t r u c t u r e f o r g l n g s e x t r u s i o n s and c a s t i n g and t h i n w a l l t u b i n g t o p l a t e f o r heat exchangers M a t e r i a l s are molybdenum a l l o y s f o r s e r v i c e t o 2800 F w i t h o x i d a t i o n p r o t e c t i v e c o a t i n g s or f o r h i g h e r temperature components i n c o r p o r a t i n g ceramic i n s u l a t i o n e x t e r n a l t o s k i n F i t t i n g s up t o 36 Inches sheet and p l a t e d e t a i l s t o 48 inches AARP REFERENCES E Chart . 6 1 . 6A. 88. 9 1 . 117. 227 274 B Chart. 28c d 29b 30a 31a 32a 41a 42a 51b 110a 122a 123 P4FVPS Chart. J o i n i n g No 8 9 and 11 APPLICABLE PROCESS YIELD STRENGTH CONTROLLED DIFFUSION BONDING ( u s i n g h i g h p r e s s u r e and s h o r t t i m e ) o r CREEP COOTROLLED DIFFUSION BONDING ( u s i n g low p r e s s u r e and lo n g t i m e ) Code 6 09 01 6 09 02 STATE OF THE ART ASSESSMENT Y i e l d S t r e n g t h C o n t r o l l e d D i f f u s i o n Bonding Molybdenum a l l o y s have been d i f f u s i o n bonded on a developmental b a s i s u s i n g the l o c a l i z e d y i e l d s t r e n g t h c o n t r o l l e d process l i m i t e d t o s m a l l t e s t specimens and gauges A p p r o x i m a t e l y 12 000 p s l p r e s s u r e and 2600 F temperatures were used w i t h i n t e r m e d i a t e m a t e r i a l s o f t a n t a l u m columblum and vanadium Based on h i g h temperature t e s t s o x i d a t i o n r e s i s t a n c e and c o m p a t i b i l i t y w i t h s i l l c l d e type c o a t i n g s the columblum I n t e r m e d i a t e o f f e r e d the best compromise f o r J o i n t s t r e n g t h R o l l bonding a l s o u t i l i z e s h i g h bonding pressure and lends i t s e l f t o the f a b r i c a t i o n o f c o r r u g a t e d o r s t i f f e n e d s k i n s t r u c t u r e but has n o t been developed f o r molybdenum The process i s l i m i t e d t o f l a t p a n e l s w i t h c o r r u g a t i o n s or s t l f f e n e r s r u n n i n g p a r a l l e l t o the r o l l i n g d i r e c t i o n Subsequent f o r m i n g o p e r a t i o n s are r e q u i r e d R e t o r t and t o o l i n g m a t e r i a l s r o l l i n g procedures and t o o l i n g removal methods may r e q u i r e development a l t h o u g h the process has been e x t e n s i v e l y developed f o r t i t a n i u m Creep C o n t r o l l e d D i f f u s i o n Bonding I n i t i a l s t u d i e s have been conducted on TZM a l l o y s f o r creep c o n t r o l l e d bonding u s i n g the e l e c t r i c b l a n k e t process R e s u l t s f r o m c u r r e n t e f f o r t on y i e l d s t r e n g t h c o n t r o l l e d bonding and use o f i n t e r m e d i a t e m a t e r i a l s t o promote bonding may be p a r t l y a p p l i c a b l e t o creep c o n t r o l l e d bonding u s i n g e l e c t r i c b l a n k e t process where low pressures and long times are r e q u i r e d The e l e c t r i c b l a n k e t low pressure process has been used f o r bonding o f TZM a l l o y faced t o honeycomb core T r i a l s were l i m i t e d by l a c k o f acceptable core C l e a n i n g s u r f a c e p r e p a r a t i o n and d i m e n s i o n a l c o n t r o l o f c l o s e t o l e r a n c e d e t a i l p a r t s are c r i t i c a l f o r s e l f bonded J o i n t s CRITICAL PROBLEMS 1 C a p a b i l i t y o f d i f f u s i o n bonding processes and equipment t o p r o v i d e j o i n t a c c e s s i b i l i t y and t o produce the s t r u c t u r a l shape t o the r e q u i r e d t o l e r a n c e w i t h o u t d e f o r m a t i o n w i t h i n the bonding parameters o f temperature p r e s s u r e and time ALTERNATE PROCESSES NONE Continued on next page Code
286 2 Atmosphere c o n t r o l d u r i n g bonding which would be a p p l i c a b l e t o l o c a l i z e d processes and to those which I n v o l v e t h e use o f e n c a p s u l a t i n g m a t e r i a l s and t o o l i n g m a t e r i a l s 3 De g r a d a t i o n o t m a t e r i a l p r o p e r t i e s a s s o c i a t e d w i t h bonding temperature and time and by I n t e r m e d i a t e m a t e r i a l d u r i n g p r o c e s s i n g o r subsequent s e r v i c e A C o m p a t i b i l i t y o f I n t e r m e d i a t e m a t e r i a l s w i t h o x i d a t i o n r e s i s t a n t c o a t i n g s and p r o c e s s i n g 3 R e t o r t and t o l l i n g m a t e r i a l s > Assembly t o l e r a n c e s p r i o r t o r o l l bonding and removal o f t o o l i n g m a t e r i a l s a f t e r r o l l bonding ' Forming o f f l a t r o l l bonded panels t o contour I S t r e n g t h o f r o l l bonded J o i n t s and e f f e c t o f process on p a r e n t m e t a l p r o p e r t i e s PROPOSED DEVELOPMENT PROGRAM C H A R L NO TJV CRITICAL PROBLEMS, c o n t i n u e d OBJECTIVE BACKGROUND APPROACH To develop p r o c e s s i n g data on the d i f f u s i o n bonding o f molybdenum a l l o y s e s t a b l i s h i n g the e x t e n t t o which molybdenum can be bonded by bo t h y i e l d s t r e n g t h and creep c o n t r o l l e d processes The b r l t t l e n e s s o f molybdenum and I t s d i f f u s i o n bonded J o i n t s which can become more severe I n s e r v i c e I s viewed as a d e t e r r e n t t o I t s use compared t o a l t e r n a t e m a t e r i a l s More I n f o r m a t i o n on the m e r i t s and disadvantages o f I n d i v i d u a l t e c h n i q u e s I s d e s i r e d I n c l u d i n g f a b r i c a t i o n o f subscale components I n c o r p o r a t i n g t y p i c a l d e s i g n c o m p l e x i t i e s such as edge members l o c a l attachment p o i n t s e t c E f f o r t should be paced by how pr o m i s i n g molybdenum m a t e r i a l developments prove t o be I n r e l a t i o n t o a l t e r n a t e m a t e r i a l s 1 Determine the f e a s i b i l i t y o f p r o d u c i n g c l o s e t o l e r a n c e s t r u c t u r a l shapes f o r molybdenum a l l o y s w i t h o u t d e f o r m a t i o n by both creep c o n t r o l l e d and y i e l d s t r e n g t h c o n t r o l l e d processes These processes c o u l d combine l o c a l i z e d J o i n i n g processes such as spot bonding and gas pressure or press bonding t e c h n i q u e s depending upon c o n f l g u r a t l o n o f the p a r t J o i n t d e s i g n and a c c e s s i b i l i t y Determine bonding temperature time and pressure s u r f a c e p r e p a r a t i o n t e c h n i q u e s and I n t e r m e d i a t e m a t e r i a l r e q u i r e m e n t s t o produce d i f f u s i o n bonded J o i n t s between honeycomb core and face sheets u s i n g creep c o n t r o l l e d methods o f low p r e s s u r e and lo n g time t o p r e v e n t panel damage 2 For r o l l d i f f u s i o n bonding determine r o l l i n g temperatures m i l l r e d u c t i o n s p u r g i n g procedures c l e a n i n g and s u r f a c e p r e p a r a t i o n I n c l u d i n g f i t up t o l e r a n c e s and s u r f a c e f i n i s h e s necessary t o produce the f i n a l p a r t c o n f i g u r a t i o n and dimensions 3 Develop equipment and t o o l i n g m a t e r i a l s which w i l l p r o v i d e r e l i a b l e atmo p h e r l c c o n t r o l d u r i n g bonding T h i s I n c l u d e s chambers f o r l o c a l i z e d bonding and e n c a p s u l a t i n g ] m a t e r i a l s and t o o l i n g capable o f h i g h t e m p e r a t u i e s p r e s s u r e s and long times r e q u i r e d f o r creep bonding processes it For r o l l d i f f u s i o n bonding e s t a b l i s h r e t o r t and t o o l i n g m a t e r i a l s c o m p a t i b l e w i t h molybdenum a l l o y s and the p r o c e s s i n g c o n d i t i o n s f o r them I n c l u d i n g removal o f t o o l i n g by mechanical or chem i c a l means which w i l l not degrade the p a r t s 5 Determine the e f f e c t o f creep c o n t r o l l e d bonding processes I n v o l v i n g two pressures and l o n g time a t temperature on r e f r a c t o r y m e t a l p r o p e r t i e s and J o i n t s t r e n g t h and the use of i n t e r m e d i a t e m a t e r i a l s t o reduce bonding pressure and temperature 6 For r o l l d i f f u s i o n bonding determine the e f f e c t o f the bonding c y c l e Cooling m a t e r i a l s f o r m i n g process and t o o l removal methods on J o i n t s t r e n g t h and par e n t m e t a l p r o p e r t i e s 7 Develop procedures and methods f o r f o r m i n g r o l l bonded panels t o f i n a l shape e i t h e r a t room or e l e v a t e d temperatures and e i t h e r w i t h or w i t h o u t p r i o r removal o f t o o l i n g 8 Determine the e f f e c t o f o x i d a t i o n r e s i s t a n t c o a t i n g s and processes on I n t e r m e d i a t e m a t e r i a l s and J o i n t s t r e n g t h
287 PRIORITY RATING WORKSHEET P R Q g R A M F A C T O R S P R O G R A M P R O B A B I L I T V O F S U C C E S S ⢠L O W Z ⢠MOoeRATE 5 CRITICAL PROBLEMS TO BE SOLVED a F E W / N O T TOO PIFFWUUT Z â¢pl 3 0 M e / D I F F I C U L T a P M A N Y / V E R Y D I F F I C U L T 6 P R O C E S S G R O W T H P O T E N T I A L ⢠L I T T L E O R U N D E F I N A B L E O )S lZe^:«6NIZ.ABLE P O T E M T I A L 4 APPLI CATIONS OTHER TMAN AIR FORCE ⢠NONE O S O M E 4 D MANY e NECESSITY FOR AIR FORCC FUNDINO ⢠LOW HiiSH i«uuSTay/<rrH£A Sovr CFFeir * Meoea/xTE - Sdne EFr<«.r orHfX 'Scucces e a e x ^ u i s i v E A I R F»llCb F U M C M A U K C L W I ^ NEED FACTORS SYSTEMS P R O B A B I L I T Y HIQH P t o B A B l L I T Y 12 FAIR P R O B A B I L I T Y 8 LOW P R O B A B I L I T Y 4 C O M P O N E N T C R I T l O A L I T Y VERY HKTH IZ HIAH 9 FA IR 6 LOW 3 F R E a u E N C Y OF REQUIREMENT IN « V « T E M M«B£ THAW 3 CeMPeHEMTS 3 "2. 3 CeMPoMENTS 2 S I N f l L E OeMPWMENT I D E S I S N A L T E R M A T E S No ALTERNATe R m E s E E N ONE AL-TEBNATE 6 S E V E H A L AUTERMATES 3 M A T E R I A L S IMPLICATION New MATERIAL 0£veu>(>ueNT B c a o £ MATERIAL IMPROVEMENT R E A P 4 NO PROOLEM F o R C S c e i a o CALCULATE PRIORITY CIRCLE 8 RAW SCoflES F O R BACM REFCREMftP COMPONENT IN TABceS AT tND OF PANEL Rt(>«tT W I T H liAM ToTrtW ENTERTP IN <3ilMMAEV A T 1216MT CHART , NO "^^7 AARP RA>M scopes | 2 - ? l l * S | | f 5 p | Z2 1 1 3i 1 1 3a. 1Ì 5551 I z V l l 271 3o U r I iJoWtf- vf-W II 1 /f 36 H> |*?| F T T i r - i r n r n r n 1 »»||2»||ZZ| ⢠n B /A 1 1 1 1 S/6 kS^Lz^JI 1 L J B-'ZA I I J / 1 2.? \m e 2e 1 2611/6 l l / fe 1 /£ p r ] l (5o) | |2 .v l|i7| 2 7 1 1 ⢠⢠a 1 1 1 1 ⢠n n r n n r n m m 1 ^jâiiâ11 ^ i â I ⢠⢠⢠U n r n r - i r n i â i n S T E P I S T E P Z S T E P 3 n c H I S H E S T A A R P RAW S C O R E IN eACH OTHER S V S T e M C I R C L E NEXT H I S M E S T S C O R E IF WITHIN 4 P O I M T S O F T O P S C O R t ^ L O W ^ NUMBER OF SVSTEWS H ldH C I R C L E F R E Q U E N C Y DISTRIBUTION F A C T O R NUMQER. OP SyST-EMS HlSri I 2 3 «e MMLE N U M & E R OF S Y S T E M S Low 0 I 2 H M O S E 1 0 1 a 1 4 1 1 1 3 11 1 2 . 1 «f 0 4 ) B&LOWi P = T O T A L = ^6 11- PRIORITY I ( P HI
288 TITLE DIFFUSION BONDING OF COLUMBIUM ALLOY SHEET PLATE AND HONEYCOMB ASSEMBLIES CHART NO ^32 PRIORITY RELATED CAMR CHARTS 7^)V MANUFACTURING REQUIREMENT To J o i n by d i f f u s i o n bonding honeycomb core t o faces and edge members t y p i c a l sheet metal d e t a i l s such as p l a i n and c o r r u g a t e d s k i n s r i b s s t l f f e n e r s and s m a l l r a d i u s c o n i c s e c t i o n s o f gauges from 0 010 i n c h t o 0 100 i n c h h e a v i e r p l a t e gauges t o produce l a r g e r complex f i t t i n g s J o i ned t o s k i n and frame s t r u c t u r e s f o r g i n g s e x t r u s i o n s and c a s t i n g s and t h i n w a l l e d t u b i n g t o p l a t e f o r heat exchangers M a t e r i a l s are columbium a l l o y s f o r s e r v i c e t o 2500 F w i t h o x i d a t i o n p r o t e c t i v e c o a t i n g s o r f o r h i g h e r temperature components i n c o r p o r a t i n g ceramic I n s u l a t i o n e x t e r n a l t o s k i n F i t t i n g s up t o 36 inches sheet and p l a t e d e t a i l s t o A8 inches AARP REFERENCES E Chartf Charts _ bl* 88 91 117 227 27A B 28c, 29b 30a 31a 32a A l a A2a 50a b 51b 110a 122a 123 P4FVPS r^â^. J o i n i n g No 5 8 9 10 and 11 APPLICABLE PROCESS YIELD STRENGTH CONTROLLED DIFFUSION BONDING ( u s i n g h i g h pressure and s h o r t t i m e ) o r CREEP CONTROLLED DIFFUSION BONDING ( u s i n g low p r e s s u r e and lo n g t i m e ) Code 6 09 01 6 09 02 STATE OF THE ART ASSESSMENT Y i e l d S t r e n g t h C o n t r o l l e d D i f f u s i o n Bonding Columbium a l l o y s i n c l u d i n g D-36 D-A3 and B-66 have been d i f f u s i o n bonded on a develop mental b a s i s u s i n g l o c a l i z e d y i e l d s t r e n g t h c o n t r o l l e d process A s m a l l p r o t o t y p e s t r u c t u r e has been f a b r i c a t e d t o show process f e a s i b i l i t y D 36 and B-66 a l l o y s are p a r t i c u l a r l y amenable t o d i f f u s i o n bonding and can be bonded w i t h o u t the use o f i n t e r m e d i a t e m a t e r i a l s a t temperatures o f 2A50 F t o 2600 F and pres s u r e s o f 12 000 p s l Cleaning and s u r f a c e p r e p a r a t i o n are c r i t i c a l f o r s e l f bonded J o i n t s The D A3 a l l o y bonded best w i t h t a n t a l u m I n t e r m e d i a t e m a t e r i a l Gas pres s u r e bonding has been used on a l i m i t e d b a s i s i n the e v a l u a t i o n o f s m a l l t e s t specimens The longer bonding c y c l e r e s u l t e d i n some creep d e f o r m a t i o n and some l o s s i n d u c t i l i t y o f the paren t m a t e r i a l R o l l d i f f u s i o n bonding I s a method which would lend I t s e l f t o p r o d u c t i o n o f c o r r u g a t e d or s t i f f e n e d s k i n s t r u c t u r e but has n o t been developed f o r columbium The process i s l i m i t e d t o f l a t p anels w i t h c o r r u g a t i o n s or s t l f f e n e r s r u n n i n g p a r a l l e l t o each o t h e r and i n the r o l l i n g d i r e c t i o n Subsequent f o r m i n g o p e r a t i o n s would be r e q u i r e d R e t o r t and t o o l i n g m a t e r i a l s r o l l i n g procedures and t o o l i n g removal methods may r e q u i r e development a l t h o u g h t h e process has been e x t e n s i v e l y developed f o r t i t a n i u m Creep C o n t r o l l e d D i f f u s i o n Bonding Creep c o n t r o l l e d d i f f u s i o n bonding o f Cb a l l o y s has been f e a s i b l e w i t h f l a t and curved honeycomb panels and lamin a t e d s t r u c t u r e s A l l o y s which have proven s u c c e s s f u l i n c l u d e B 66 D A3 Cb 752 C 129Y and FS 85 I n t e r m e d i a t e f o i l s such as t i t a n i u m and t a n t a l u m have been u t i l i z e d , as w e l l as s e l f bonding process f e a s i b i l i t y Small p r o t o t y p e s t r u c t u r e s have been f a b r i c a t e d t o show Honeycomb sandwich panels o f columbium 752 a l l o y have been d i f f u s i o n bonded i n s i z e s up t o 2 f t X 3 f t and t o a 30 i n c h r a d i u s c u r v a t u r e u s i n g e l e c t r i c b l a n k e t method and creep c o n t r o l l e d bonding process An i n t e r m e d i a t e m a t e r i a l o f t i t a n i u m f o i l was used w i t h bonding temperature o f 2200 F f o r 6 hours a t 15 p s l o f area f o r 3/16 i n c h c e l l s i z e and 0 002 i n c h f o i l honeycomb core Panels v a r i e d s l i g h t l y i n d i m e n s i o n a l t o l e r a n c e due t o temperature g r a d i e n t s d u r i n g Continued on next page
289 STATE OF THE ART ASSESSMENT c o n t i n u e d h e a t i n g and c o o l i n g Dimensional c o n t r o l o f d e t a i l s and f i t - u p bonding and atmosphere c o n t r o l d u r i n g bonding c l e a n i n g and s u r f a c e p r e p a r a t i o n p r i o r t o i s c r i t i c a l CRITICAL PROBLEMS 1 C a p a b i l i t y o f d i f f u s i o n bonding processes equipment and t o o l i n g t o p r o v i d e J o i n t access I b l l i t y and t o produce t h e s t r u c t u r a l shape t o t h e r e q u i r e d t o l e r a n c e w i t h o u t d e f o r m a t i o n w i t h i n the bonding parameters o f temperature pressure and time 2 C o n t r o l o f c l e a n i n g and su r f a c e p r e p a r a t i o n t o p r o v i d e u n i f o r m bonding 3 Atmosphere c o n t r o l d u r i n g bonding t o pr e v e n t c o n t a m i n a t i o n d u r i n g l o c a l i z e d bonding and processes u s i n g e n c a p s u l a t i n g m a t e r i a l s ( r e t o r t s ) and t o o l i n g m a t e r i a l s 4 Degradation o f m a t e r i a l p r o p e r t i e s a s s o c i a t e d w i t h l o n g bonding c y c l e s and h i g h temperature 5 R e t o r t and t o o l i n g m a t e r i a l s 6 Assembly t o l e r a n c e s p r i o r t o r o l l bonding and removal o f t o o l i n g m a t e r i a l s a f t e r r o l l bonding 7 Forming o f f l a t r o l l bonded panels t o con t o u r 8 S t r e n g t h o f r o l l bonded J o i n t s and e f f e c t o f process on p a r e n t m e t a l p r o p e r t i e s PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To extend the d i f f u s i o n bonding c a p a b i l i t i e s f o r columbium a l l o y s by g e n e r a t i n g a d d i t i o n a l p r o c e s s i n g data f o r b o t h y i e l d s t r e n g t h and creep c o n t r o l l e d processes and process v e r i f i c a t i o n by p r o t o t y p e hardware f a b r i c a t i o n and e v a l u a t i o n BACKGROUND The p o t e n t i a l u s e f u l n e s s o f columbium a l l o y s appears s u f f i c i e n t l y ensured t h a t f u r t h e r advancement o f the d i f f u s i o n bonding techniques i s warranted t o demonstrate d e s i g n v e r s a t i l i t y and p r o v i d e c o n f i d e n c e o f minimum r i s k t o u s i n g v e h i c l e s and systems APPROACH 1 Develop equipment t o o l i n g m a t e r i a l s and h e a t i n g methods f o r e l e c t r i c b l a n k e t and press bonding processes which w i l l w i t h s t a n d h i g h temperatures and pr e s s u r e s f o r l o n g times and capable o f pr o d u c i n g panels o f the r e q u i r e d shape s i z e and t o l e r a n c e T h i s should i n c l u d e chambers f o r l o c a l i z e d bonding and adequate p r o v i s i o n f o r p u r g i n g and r e l i a b l e atmosphere c o n t r o l f o r the v a r i e t y o f s t r u c t u r e s i n c l u d i n g sandwich panels w i t h u n p e r f o r a t e d honeycomb core Determine the f e a s i b i l i t y o f prod u c i n g c l o s e t o l e r a n c e s t r u c t u r a l shapes w i t h o u t d e f o r m a t i o n u s i n g a creep con t r o l l e d J o i n i n g process 2 For r o l l d i f f u s i o n bonding e s t a b l i s h r e t o r t and t o o l i n g m a t e r i a l s compatible w i t h columbium a l l o y s and t h e i r p r o c e s s i n g c o n d i t i o n s i n c l u d i n g removal o f t o o l i n g by mechanical o r chemical means which w i l l n o t degrade the p a r t Determine r o l l i n g t emperatures and m i l l r e d u c t i o n s 3 E s t a b l i s h s u r f a c e p r e p a r a t i o n and c l e a n i n g techniques f o r columbium a l l o y s sheet p l a t e honeycomb core and I n t e r m e d i a t e m a t e r i a l s f o r the r e s p e c t i v e d i f f u s i o n bonding techniques I n c l u d i n g f i t - u p t o l e r a n c e s and su r f a c e f i n i s h requirements f o r the r o l l d i f f u s i o n bonding process 4 Develop procedures and methods f o r f o r m i n g r o l l bonded panels t o f i n a l shape e i t h e r a t room or e l e v a t e d temperatures and e i t h e r w i t h or w i t h o u t p r i o r removal o f t o o l i n g 5 Determine the e f f e c t o f temperature time and bonding pressure on the j o i n t s t r e n g t h and pa r e n t m a t e r i a l p r o p e r t i e s 6 Determine the e f f e c t o f o x i d a t i o n r e s i s t a n t c o a t i n g s and the c o a t i n g processes on i n t e r m e d i a t e m a t e r i a l s and J o i n t s t r e n g t h s
290 PRIORITY RATING WORKSHEET PROGRAM P R O B A B I L I T Y OF S U C C E S S a LOW 2 ⢠MODERATE 5 ^ W&H 8 C R I T I C A L P R O B L E M S TO B E SOLVED ⢠F E W / N O T TOO DIFFICULT 2. fi S O M E / D I F F I C U L T 3 a M A N Y / VERY DIFF ICULT 8 P R O C E S S G R O W T H P O T E N T I A L ⢠LITTLE OR U N O E F I N A B L E O X Re^^OfiNllABLE POTEMTIAL 4 APPLICAT IONS OTHER THAN AIR FORCE ⢠NONE O ^ SOME 4 D MANY e N E C E S S I T Y FOR AIR F O R C E FUNDIMQ ⢠LOW Hifif iiiuuSTtty/'crH£« <s«r CFFoar * JgC fMODCCATE - SCPtF EFFOCT OTHCK Ì OUS^C^ B a ttcwswe Am fetua. F U M P M S U K C L V i t NEED FACTORS S Y S T E M S P R O B A B I L I T Y H I Q H P R O B A B I L I T Y FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T I O A L I T Y VERY H I « H H I « H FAIR L o w F R E a u E N C Y OF REQUIREMENT IN S Y S T E M MSne THAN 3 C0MP«NEMT9 â¢2. 3 COMPONENTS S l N f l L E CeMPONENT OEQIGN A L T E R M A T E S No ALTEBNATE R I S E 8 E E N ONE ALTEBNATC S E V E R A L A L T E R N A T E * M A T E R I A L S IMPLICATION New MATERIAL PEVttOfMtNT RCA O MATCKlAL IMPROVEMCNT B£|B V NO PROBLEM F o R C S C e k l 12 8 4 VL 9 3 3 2 I 3 6 4 o CALCULATE S T E P I S T E P 2 PRIORITY RAW s c o i i e s F O R EACH REFEKeNfEP COMWNCNT IN TABLtS AT tWD OF PANEL RtPOtT WITH T O T A L S ENTEOCP (N AT CHART NO _ ^S8 A A R P RAVa S C O R E S [ i z i [ i a n n 1 1 1 1 / ) 3a [ ^ l 3 V M Z 7 l l ^ e r ^ | 2 7 | 2 y | | * < * 1 1 3h 12* 11 2 3 l l / i 11/6 ⢠/)3e 1 2 i 11Ì 2-11*211 n /»*/*fs) ^3^\3( \\%i\\it n B /A UrI S /b L_J g 2a. 1 ^ vjn\3i\\ \\ II 1 SZe \Z&\\H,\\Zi\\f(. ⢠S3a. | 0 O l 3 - y | U 7 l l i 7 ⢠⢠⢠⢠H Z n n n n , n n n n i n i n 1 â ^ i n n n n n n n n i n n n n n i n n n n n n n n n i n n n n n n n i n n n n n us CIRCLE HIGHEST A A R P RAW S C O R E IN EACH OTHER S Y S T E M C I R C L E NEXT H I G H E S T IF WITHIN 4 P O I N T S O F T O P S C O R E n ^ tow ^ 3Â¥ I NUMBER OF ^VSTEMS HIdIM S T E P 3 C I R C L E F R E Q U E N C Y DISTRIBUTION F A C T O R NUMieeR. ov SYSTEMS Hieri 1 2. 3 oil M»eE S C O R E BELOWt NUMeCR O F S Y S T E M S LOW 0 I 2 R Mode 1 0 t a I 4 1 t t 3 1 f 1 z 1 *f T O T A L PRIORITY
291 TITLE JOINING OF FILAMENT-REINFORCED METALS CHART NO PRIORITY RELATED CAMR C H A R T S , 161. 7flV AARP REFERENCES F flhartc 60 ( s u b s t i t u t e m a t e r i a l ) B rKnrt. 31d ^ s u b s t i t u t e m a t e r i a l ) P A F V P S Charts . ^ APPLICABLE PROCESS Code NO PREFERENCE MANUFACTURING REQUIREMENT To J o i n f i l a m e n t r e i n f o r c e d metals as these are developed t o r e p l a c e p r e s e n t m a r g i n a l or inadequate m a t e r i a l s An example i s an i n s u l a t e d and cooled s t r u c t u r e (B31d) where y i e l d / d e n s i t y r a t i o o f 800 000 i n c h a t 1000 F cannot now be met The r e f e r e n c e c h a r t s i n d i c a t e d below are c i t e d as an example o f where f i l a m e n t r e i n f o r c e d m e t a l s might be a p p l i e d STATE OF THE ART ASSESSMENT F i l a m e n t r e i n f o r c e d metals are a r e c e n t development not consid e r e d by AARP One example o f a p o t e n t i a l a p p l i c a t i o n has been s e l e c t e d (B-31d) so t h a t the p r o s p e c t i v e use o f the m a t e r i a l can be h i g h l i g h t e d Other p o s s i b i l i t i e s c o u l d be i d e n t i f i e d by thorough r e v i e w o f AARP component a n a l y s i s Many f i l a m e n t r e i n f o r c e d m e t a l s have been developed I n the form o f sheets Aluminum r e i n f o r c e d w i t h s t a i n l e s s s t e e l and b e r y l l i u m has been produced i n sheets up t o a few f e e t i n s i z e a l t h o u g h not on a p r o d u c t i o n b a s i s Development o f aluminum-boron and aluminum s i l i c o n c a r b i d e I n the form o f sheets e x t r u s i o n s o f T i TZM tape o f T i B and many o t h e r systems i s i n p r o g r e s s These f i l a m e n t r e i n f o r c e d metals are l a r g e l y r e i n f o r c e d i n one d i r e c t i o n but some b i a x i a l r e i n f o r c e d composites have been made i n A l Be Many other methods o f p r o d u c t i o n and d i f f e r e n t c o m p o s i t i o n s are under study When t h e r e i s a l a r g e d i f f e r e n c e i n the m e l t i n g temperature i n t h e t h e r m a l d i f f u a l v l t y and e l e c t r i c a l c o n d u c t i v i t y o f th e m e t a l m a t r i x and o f the r e i n f o r c i n g f i b e r I t should be p o s s i b l e t o combine the r e s i s t a n c e and f u s i o n w e l d i n g processes w i t h s u i t a b l e designs t o produce an e f f e c t i v e l i g h t w e i g h t J o i n t I n the m a n u f a c t u r i n g o f heat sensors thermocouple w i r e s have been c a s t i n t o a spot weld nugget produced i n an aluminum a l l o y body The thermocouple w i r e s are not damaged by the spot w e l d i n g process s i n c e the I 2 R I S a d j u s t e d t o the v a l u e r e q u i r e d t o m e l t the aluminum S i m i l a r l y i t i s expected t h a t aluminum r e i n f o r c e d w i t h f i n e s t e e l w i r e s c o u l d be spot welded w i t h o u t damaging t h e r e i n f o r c i n g f i l a m e n t s The d i f f e r e n c e i n m e l t i n g temperature I s s u f f l c l e n t l y l a r g e (about 600 C f o r aluminum ver s u s 1500 C f o r s t e e l ) and the w e l d i n g time i s so s h o r t (0 05 seconds f o r 0 062 + 0 062 Inches) t h a t the s t e e l f i l a m e n t s w i l l not be damaged w h i l e the aluminum m a t r i x i s l o c a l l y m e l t e d The d i f f e r e n c e i n e l e c t r i c a l c o n d u c t i v i t y between the two me t a l s i s undoubtedly a l s o o f s i g n i f i c a n c e i n t h e s u r v i v a l o f th e r e i n f o r c i n g f i b e r Continued on next page ALTERNATE PROCESSES NONE Code
292 CHART NO y < g 7 CRITICAL PROBLEMS The c r i t i c a l problem i s (1) load t r a n s f e r i n an a n l s t r o p i c m a t e r i a l Many aspects o f t h i s problem are a p p r e c i a t e d based on load t r a n s f e r s t u d i e s w i t h i n r e i n f o r c e d m a t e r i a l s Design o f J o i n t s w i l l be more i m p o r t a n t than process chosen Other problems are (2) w e i g h t o f j o i n t Long s c a r f J o i n t s d o u b l e r s and o t h e r methods w i l l g i v e s t r o n g J o i n t s but are e x c e s s i v e l y heavy (3) Load r e l a x a t i o n i n m a t r i x ( 4 ) Damage t o f i l a m e n t r e i n f o r c e d m e t a l by i n t e r a c t i o n i n J o i n i n g c y c l e ( 5 ) Damage t o J o i n t by i n t e r a c t i o n o f f i l a m e n t s w i t h f i l l e r m e t a l e g braze a l l o y I n a d d i t i o n t o g e n e r a l problems a s s o c i a t e d w i t h f i l a m e n t - r e i n f o r c e d m e t a l s t h e r e are s p e c i f i c problems a s s o c i a t e d w i t h each f i l a m e n t - m a t r i x c o m b i n a t i o n and g e n e r a l problems a s s o c i a t e d w i t h the J o i n i n g process PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To d e s i g n and develop J o i n t s s u i t a b l e f o r use w i t h f i l a m e n t r e i n f o r c e d metals and t o develop methods t o f a b r i c a t e such J o i n t s BACKGROUND F i l a m e n t - r e i n f o r c e d metals w i l l become a v a i l a b l e i n 1970 85 f o r c r i t i c a l s t r u c t u r e s a p p l i c a t i o n s such as where h i g h s t i f f n e s s i s r e q u i r e d or where h i g h e r temperature a p p l i c a t i o n o f aluminum and t i t a n i u m i s needed These m a t e r i a l s w i l l be h i g h l y a n i s o t r o p i c i n a t l e a s t one d i r e c t i o n a l t h o u g h r e c e n t work on a A p l y panel o f A l Be w i r e composite f a b r i c a t e d w i t h a l t e r n a t e o r t h o g o n a l l a y e r s showed c l o s e approach t o I s o t r o p y i n the plane o f the sheet Normal t o the sheet 1 e i n the s h o r t t r a n s v e r s e d i r e c t i o n the p r o p e r t i e s w i l l be c o n t r o l l e d by the p r o p e r t i e s o f the m a t r i x Attachments t o the s u r f a c e o f such a sheet and J o i n t s between such sheets w i l l be s u c c e s s f u l t o the e x t e n t t h a t load can be t r a n s m i t t e d through the m a t r i x from f i l a m e n t t o f i l a m e n t APPROACH A t h r e e phase program i s proposed Phase I A n a l y t i c a l Study a) A n a l y s i s o f problem b) Survey o f m a t e r i a l forms c ) I d e n t i f i c a t i o n o f J o i n t s r e q u i r e d d) Load t r a n s f e r problems i n c l u d i n g s t r e s s c o n c e n t r a t i o n e f f e c t s and load r e l a x a t i o n problems Phase I I J o i n i n g Method Development a) I n t e r a c t i o n l i m i t b) Brazed J o i n t s c ) D i f f u s i o n bonded J o i n t s d) Welded J o i n t s w i t h added w i r e s E) New J o i n i n g methods F) N o n - d e s t r u c t i v e t e s t i n g Phase I I I - E v a l u a t i o n o f J o i n t s a) Test J o i n t s b) Simulated s t r u c t u r e s c) Demonstration s t r u c t u r e d) Non d e s t r u c t i v e t e s t i n g e) Simulated s e r v i c e t e s t s on s t r u c t u r e s Continued on next page
293 CHART NO Hot k?BJECTIVE IBACKGROUND topROACH INSPECTION TECHNIQUES SUPPLEMENTAL RECOMMENDATIONS 1 To p r o v i d e methods t o e v a l u a t e developmental compoeite systems o f f i l a m e n t s i n m e t a l m a t r i c e s t o promote the development o f these p r o m i s i n g composites 2 To I n s u r e the e x i s t e n c e o f adequate i n s p e c t i o n and e v a l u a t i o n techniques f o r components manufactured from f i l a m e n t / m e t a l composites The f i b e r r e i n f o r c e d m e t a l composites are p r o m i s i n g s t r u c t u r a l m a t e r i a l s w i t h h i g h s t r e n g t h / w e i g h t p r o p e r t i e s but no mode o f f a i l u r e or c h a r a c t e r i z a t i o n e x i s t s f o r these m a t e r i a l s nor have any i n s p e c t i o n and e v a l u a t i o n techniques been a p p l i e d and ev a l u a t e d The o n l y i n s p e c t i o n s t a t e o f the a r t a t pre s e n t I s the analogous problem o f the g l a s s f i b e r r e i n f o r c e d p l a s t i c s A t t r i b u t e s t o be measured should be f i b e r t o m a t r i x r a C i o o r i e n t a t i o n o f f i b e r s bond o f f i b e r and m a t r i x and the l a y and d i s t r i b u t i o n o f the f i b e r s 1 P e r f o r m modes-of f a i l u r e analyses t o i n d i c a t e the c h a r a c t e r i s t i c s t h a t must be Ins p e c t e d or e v a l u a t e d I t may be sp e c u l a t e d t h a t the modes-of f a i l u r e w i l l r e s u l t from f a i l u r e o f a weak bond b r i t t l e f a i l u r e I n a d i f f u s i o n l a y e r between f i b e r s and m a t r i x and r u p t u r e o f f i b e r s 2 S e l e c t two or more composite systems t h a t w i l l be r e p r e s e n t a t i v e o f the spectrum o f systems t h a t may be used and t h a t w i l l b r a c k e t the a n t i c i p a t e d i n s p e c t i o n problems (e g one system w i t h f i b e r and m a t r i x h a v i n g s i m i l a r p h y s i c a l p r o p e r t i e s and the o t h e r w i t h w i d e l y d i s s i m i l a r p h y s i c a l p r o p e r t i e s ) 3 a E x p l o r e r a d i o g r a p h i c methods f o r l a y and o r i e n t a t i o n o f f i b e r s and x ray t r a n s m i s s i o n / a t t e n u a t i o n techniques f o r r a t i o o f f i l a m e n t t o m a t r i x b E x p l o r e a p p l i c a t i o n s o f l o n g i t u d i n a l p u l s e echo shear wave and through t r a n s m i s s i o n s u l t r a s o n i c techniques ( I n c l u d e measurement o f v e l o c i t i e s and a t t e n u a t i o n ) f o r c o r r e l a t i o n w i t h p r o p e r t i e s f i l a m e n t o r i e n t a t i o n r u p t u r e d f i l a m e n t s and o t h e r c h a r a c t e r i s t i c s c E x p l o r e a p p l i c a t i o n o f Eddy-current techniques (phase and amp l i t u d e measurements and d i r e c t i o n a l probe c o l l s ) t o the e v a l u a t i o n o f l a y o f f i l a m e n t f i l a m e n t t o m a t r i x r a t i o d e g r a d a t i o n r e s u l t i n g from i n t e r d i f f u s i o n and r u p t u r e d f i l a m e n t s 4 I n v e s t i g a t e p o s s i b l e a p p l i c a t i o n o f i n f r a red scanning techniques
294 PRIORITY RATING WORKSHEET C H A R T P R Q g R A M P A C T O a S PR06RAM P R p B A B I L I T V OF S U C C E S S LOW Z MOoeRATE 5 ⢠HlfiH 8 C R I T I C A L P R O B L E M S T O B E S O L V E D a fV<H/HOT TOO DIFFUJULT Z S O M E / O I F F I C U t T a D M A N Y / VERY O IFP |CUtT S P R O C E S S G R O W T H P O T E N T I A L ⢠L ITTLE OR UNDEFINABLC O KeeOfiNaABLE PorBMTIAL 4- A P P L I C A T I O N S O T H E R T M A N A I R F O R C E ⢠NONE O X SOME ^ U MAMY 0 NeCESSITY FOR AIR FORCE FUNDINO n LOW HlfiH IMtUSIftV/'lirHEft G«r CFFelT- n ⢠MeOKATE - ^wiC EFRXLT OTHOl Ì dueÌ eS S j i ; exfuisive A I R Fee^t F U M C N A U K E L W vi. NEED FACTORS S Y S T E M S P R O B A B I L I T Y HIQH P e o B A B I L l T Y FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T l C A L I T Y VepY HICH HIAH FAIR L e w FRE«UENCY OF REQUIREMENT IM S Y S T E M M«BE THAM 3 COMPaXEUTS 2 3 COMPliMEMrS S IMOLE COMPMIENT O e s i G N A L T E R M A T E S No ALTeRNATE F b d E S E E N ONE ALTERNATE S E V E R A L ALTERUATe« M A T E R I A L S IMPLICATION New M/«TEe.iAu peveioFMCNT e e « o IVMTCRIAL IMP(U>VbMCNT RClB P NO PROBLEM f o f t t s e e u I Z 8 IZ 9 6 3 3 2 I <J 6 3 6 4 o C A L C U L A T E P R I O R I T Y /2. RAW SCORES FOR EACM REFCKEIUID CoMFDNCNT IN TABi.es AT bND o r PANEL 12EP«tT WITH liAlO ENTEREP IN <5l«MMAeV S Y ^ r e ^ s AARP »2A>W s c o w s ⢠⢠i n n i 3 ^ S T E P I C IRCLE HIGHEST A A R P RAW S C O R E n = S T E P Z IN EACH CTTHER S V S T e M C I R C L E NEXT H I O U E S T S C O R E IF WITHIN 4 P O I N T S O F T O P S C O R E n NUMBER OF â¢SySTEMS H ldH ^ ^ L O W S T E P 3 C I R C L E NUMBER OF S Y S T E M S L o w F R E O U e V l C Y D ISTRIBUTION F A C T O R NUMQCR. OC SYSTEMS KiGri I 2 BELOWl 3 OK M«<Le 0 I 2 ttK^oce 1 0 1 a 1 4 1 1 1 3 1 f 1 z 1 *!⢠p = T O T A L - 2o_ PRIORITY n
295 TITLE AlfflESIVE BONDING OF INSUUTING MATERIALS TO HEAT SHIELDS CHART PRIORITY ¥0? JJL RBUTBD CAMR CHARTSi 2A^ MANUFACTURING REQUIREMENT Bonding of tnsulotlon between heat shield and primary attuetute to survive ro-ontry w i t h a peak temperature of 1000 F f o r a maximum of 30 minutes Shear strength must be greater than 100 pal AARP REFERENCES E Charts 292 B Charts. 137a b c P4FVPS Charts. APPLICABLE PROCESS ORGANIC OR INORGANIC ADHESIVE BONDING Code 6 08 00 STATE O F THE ART ASSESSMENT Organic Adhesives are a v a i l a b l e w i t h s t r e n g t h s b e t t e r than 100 p s l a t 1000 F f o r t h i r t y m inutes The s t r o n g e s t and most s t a b l e o f adhesives a t 1000 F r e q u i r e c u r i n g a t temperatures o f 500 F or above under p r e s s u r e s o f g r e a t e r than 100 p s l These temperatures and pressures are l i k e l y t o be t o o h i g h f o r the heat s h i e l d and/or i n s u l a t i o n TGA shows t h a t some decomposition occurs a t 1000 F l i b e r a t i n g gaseous pr o d u c t s t h a t must be vented Lower s t r e n g t h adhesives w i l l meet the s t r e n g t h - t e m p e r a t u r e requirement but more tha n 50 p e r c e n t decomposition may occur a t 1000 F No good compromise appears t o e x i s t between these l i m i t s I n o r g a n i c Adhesives I n o r g a n i c ( c e r a m i c ) adhesive bonding may be used t o cement ceramic f i b r o u s I n s u l a t i o n t o m e t a l l i c s t r u c t u r a l member but appears u n s u i t a b l e f o r attachment t o a p l a s t i c (e g s i l i c a - p h e n o l i c ) heat s h i e l d C u r i n g c y c l e s and pressure r e q u i r e m e n t s are l e s s l i k e l y t o cause problems such as damage t o hea t s h i e l d or I n s u l a t i o n t h a n i n the case o f h i g h temperature o r g a n i c adhesives CRITICAL PROBLEMS Organic Adhesives 1 To a v o i d damage t o i n s u l a t i o n by excessive pressure ( I n c r e a s e 9 f k ) and t o heat s h i e l d by excessive c u r i n g temperature 2 Adhesive must no t p e n e t r a t e porous I n s u l a t i o n by c a p i l l a r i t y 3 Gas generated i n cure or on r e - e n t r y must be l i m i t e d t o amount t h a t can be vented i n time a v a i l a b l e A Adhesive must no t be damaged by long p e r i o d s i n vacuum and c o l d or space 5 D i f f e r e n t i a l expansion s t r e s s e s must be minimum (e g low modulus adhesive) I n o r g a n i c Adhesives 1 P e e l s t r e n g t h o f adhesive must be adequate t o w i t h s t a n d t h e r m a l s t r e s s e s generated by c y c l e s between space temperature and 1000 F Continued on n e x t page ALTERNATE PROCESSES NONE Code
-296 CRITICAL PROBLEMS, c o n t i n u e d CHART N O i.0.1 2 Cement must n o t be damaged by exposures t o space c o n d i t i o n s 3 Gas generated on c u r i n g must not cause damage t o o t h e r s t r u c t u r e s by pressure b u i l d up c o r r o s i o n s t r e s s c o r r o s i o n or o t h e r e f f e c t A Cement must n o t p e n e t r a t e I n s u l a t i o n mora th a n a nominal amount PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop a b e t t e r adhesive bonding method t o a t t a c h i n s u l a t i o n between heat s h i e l d and p r i m a r y s t r u c t u r e BACKGROUND The purpose o f the I n s u l a t i o n i s t o reduce heat f l o w from an a b l a t i v e type o f heat s h i e l d t o the p r i m a r y s t r u c t u r e I t i s e s t i m a t e d t h a t the J o i n t between heat s h i e l d and i n s u l a t i o n may reach 1000 F and the shear s t r e n g t h o f the J o i n t must be 100 p s i a t t h i s temperature The p r i m a r y s t r u c t u r e may be honeycomb t r u s s o r o t h e r f o r m and w i l l d e t e r m i n e t h e optimum i n s u l a t i o n and method o f placement F i b r o u s f e l t e d b a t t i n g foamed i n plac e p l a s t i c or an o r g a n i c l i q u i d poured i n pla c e and cured are t y p i c a l forms The p r i m a r y s t r u c t u r e should p e n e t r a t e the i n s u l a t i o n t o t h e minimum e x t e n t I n order t o l i m i t low r e s i s t a n c e heat f l o w paths Organic adheslves t h a t have good s t r e n g t h r e t e n t i o n a t 1000 F (FBI and F I ) r e q u i r e h i g h temperature and h i g h pressure c u r i n g Such c o n d i t i o n s may damage heat s h i e l d and i n s u l a t i o n Adheslves w i t h poorer b u t adequate s t r e n g t h r e t e n t i o n can be cured a t lower temperatures and pressures but decompose e x c e s s i v e l y so t h a t J o i n t s must be vented I n o r g a n i c adheslves t h a t can be cured a t low temperatures u s u a l l y r e l e a s e water o f h y d r a t i o n or ot h e r simple decomposition p r o d u c t s when heated t o 1000 F I n a d d i t i o n p e e l s t r e n g t h o f i n o r g a n i c adheslves i s low and they are not s u i t a b l e f o r J o i n t s between a p l a s t i c I n s u l a t i o n and a p l a s t i c heat s h i e l d The adhesive must n o t p e n e t r a t e the i n s u l a t i o n so as t o cause r e d u c t i o n o f p o r o s i t y and i n c r e a s e o f the r m a l conductance Other r e q u i r e m e n t s o f the adhesive are t h a t i t must w i t h s t a n d exposure t o the vacuum and temperatures o f o u t e r space APPROACH 1 I t i s recommended t h a t a d e t a i l e d survey be made t o determine the c a p a b i l i t i e s and l i m i t a t i o n s o f the v a r i o u s adheslves and t o assess the p o t e n t i a l o f each adhesive f o r advancement t o the req u i r e m e n t s s t a t e d e a r l i e r 2 The requ i r e m e n t s o f adheslves f o r t h i s a p p l i c a t i o n should be reviewed t o p e r m i t a more exa c t statement o f a s p e c i f i c a t i o n or s p e c i f i c a t i o n s The s p e c i f i c a t i o n must i n c l u d e r e f e r e n c e t o a l l o f the c r i t i c a l problems o u t l i n e d e a r l i e r w i t h q u a n t i t a t i v e r e q u i r e m e n t s f o r s t r e n g t h c u r i n g temperature and pre s s u r e l i m i t s TGA l i m i t s and f l o w i n t o I n s u l a t i o n l i m i t s 3 Two or t h r e e adhesive systems w i t h p o t e n t i a l f o r s c a l e up should be developed f o r t h i s a p p l i c a t i o n t o meet t h e minimum s p e c i f i c a t i o n 4 Comparative t e s t s should be made t o determine the u s e f u l range o f each adhesive
297 PRIORITY RATING WORKSHEET CHART PROGRAM FACTOM' PR06RAM PROBABIL ITY OF S U C C E S S ⢠LOW 2 ⢠MODERATE 5 S ( HISH 8 C R I T I C A L P R O B L E M S TO B E SOLVED ^ F E W / N O T TOO DIFFU^ULT 2. ⢠S O M E / D I F F I C U L T S ⢠M A N Y / VERY O l F F I C U t T S PROCeSS G R O W T H P O T E N T I A L ⢠LITTLE O R U N D E F I N A B L E O yC eecoamzn^te P O T E N T I A L 4 APPLICAT IONS OTHER THAN AIR FORCE X NONE O a SOME 4 ⢠fÌtANY e N E C E S S I T Y F O R A I R F O R C E F U N O I N Q D LOW HISH |»ltUSTBV/CTH£A GOVT C F F C l T * a MooesATE - scME E F n c r oTHce â¢ioaeoes a X EX£itisivE A I R fi>«£b pauvn& L I K E L V I^. N E E D F A C T O R S S Y S T E M S P R O B A B I L I T Y HIQH PROBABIL ITY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T l O A L I T Y VERY HKTH HI<SH FAIR L O W FREaUENCY OF REQUIREMENT IN S Y S T E M MORE THAN 3 COMPONENTS Z 3 CewPeNENTS S l N f l L E COMPONENT O e s l S N A L T E R N A T E S No ALTeiZNATE R » E 8 E E N ONE ALTERNATe S E V E R A L A L T E R N A T E * M A T E R I A L S IMPLICATION NEW MATERIAL PtVtlOPMENT et» O MATtOlAl, iMPttOveMCWT E£ia D NO PROBLEM F o U e S E E k l 12 8 ^ 9 b 3 3 2 â¢J 6 3 6 4 O C A L C U L A T E P R I O R I T Y S T E P I S T t P 2 8 7^ RAW SCoACS F O R EACM U£F£BENftP COMFCNCNT IN TABLtS AT tNC OF PANEL RtPfltT WITH T2AW T<»T\LS ENTEOCP fN â¢SOMUAtV eiSMT 8 36 CIRCLE HIGHEST AARP RAW S C O R E n = IM EACH OTHER S V S T E M C I R C L E NEXT H I G H E S T IF WITHIN 4 P O I N T S O F T O P S C O R E n 3V S C O R E NUMBER OF SVSTEWS H l d H LOW S T E P 3 C I R C L E F R E Q U E N C Y DISTRIBUTION F A C T O R f 8 E L O W « NUMBER. t>» S y S T C l ^ « I ^ 3 OK M««.e NUMBER OF S Y S T E M S L o w 0 I 2 RMeoe 1 0 1 e 1 4 1 1 1 3 1 z 1 *f 1 4 AARP RA>N SCORES ] ⢠⢠! ] ⢠⢠⢠⢠p = n x f = TOTAL= 2 6 I PRIORITY I
298 TITLE JOINING POROUS NICKEL TO STRUCTURE CHART NO PRIORITY RELATED CAMR CHARTS , MANUFACTURING REQUIREMENT J o i n f e l t e d or foamed n i c k e l t o s t r u c t u r e t o p r o v i d e a se a l which must be r e s i s t a n t t o permanent s e t and must not be e m b r i t t l e d i n space and e n t r y environment J o i n t may reach 1000 1200 F f o r 30 minutes The opening f o r which the se a l i s needed c o u l d be as l a r g e as 6 f e a t x 6 f e e t s i z e High temperature s e a l s f o r space v e h i c l e s can be made by attachment o f a porous n i c k e l base a l l o y s t r i p t o the p r i m a r y s t r u c t u r e T h i s porous m a t e r i a l w i l l be impregnated w i t h a s e a l a n t The porous m e t a l l i c member must r e t a i n a h i g h y i e l d s t r e n g t h a f t e r attachment so t h a t the se a l w i l l be r e s i l i e n t t o p e r m i t m u l t i p l e use AARP REFERENCES E rho 293 B Char ts . 138a PSFVPS Char ts . APPLICABLE PROCESS EITHER BRAZING ADHESIVE BONDING PRESSURE BONDING OR ELECTRON BEAM WELDING DEPENDING ON JOINT DESIGN Code 6 05 00 6 09 02 6 01 12 6 08 00 STATE OF THE ART ASSESSMENT B r a z i n g F e l t e d or foamed n i c k e l base a l l o y s are brazed t o shrouds f o r use as s e a l s i n gas t u r b i n e s Methods used t o a v o i d p e n e t r a t i o n o f braze a l l o y i n t o pores I n c l u d e s i n t e r i n g porous m e t a l t o f o i l b a cking b u r n i s h i n g one face o f porous m e t a l and c o n t r o l l e d braze c y c l e s w i t h l i m i t e d braze a l l o y High temperature b r a z i n g leaves the porous a l l o y i n a s o f t annealed c o n d i t i o n t h a t i s p o o r l y r e s i s t a n t t o permanent s e t I n d u c t i o n b r a z i n g i s d i f f i c u l t t o c o n t r o l t o make a r e l i a b l e bond Adhesive Bonding The j o i n t between the s t r u c t u r e and the porous m e t a l i s l a r g e l y i n compression w i t h some shear due t o d i f f e r e n t i a l t hermal expansion These are e x c e l l e n t c o n d i t i o n s f o r good p e r f o r m ance by adhesives TGA curves show some decomposition of p r e s e n t adhesives o c c u r r i n g below 1000 F and the dec o m p o s i t i o n p r o d u c t s w i l l contaminate atmosphere o f a space v e h i c l e C u r i n g temperature and pressures w i l l be ac c e p t a b l e t o porous m e t a l and p r i m a r y s t r u c t u r e Pressure Bonding T h i s process does not appear s u i t e d t o the t a s k because the pre s s u r e i s l i k e l y t o be h i g h enough t o c o l l a p s e porous m e t a l Low pre s s u r e creep c o n t r o l l e d bonding c y c l e s w a r r a n t e x p e r i m e n t a l t r i a l s however E l e c t r o n Beam Fusion Welding Some j o i n t designs may p e r m i t access by the narrow e l e c t r o n beam where the weld j o i n t would d i s t u r b o n l y a s m a l l a d j a c e n t area of the porous metal i n the s u r f a c e welded t o the base s t r u c t u r e F i l l e r a d d i t i o n s may be made t o compensate f o r s h r i n k a g e due t o c o n s o l i d a t i o n of the po-ous me t a l ALTERNATE PROCESSES NONE Code
-299 CHART^ NO HIO CRITICAL PROBLEMS B r a z i n g 1 P e n e t r a t i o n o f braze a l l o y I n t o porous m e t a l 2 A n n e a l i n g o f porous m e t a l so t h a t permanent s e t occurs r e a d i l y i n subsequent s e r v i c e 3 T o o l i n g t o h o l d porous m e t a l I n c o n t a c t w i t h p r i m a r y s t r u c t u r e w i t h o u t deforming porous m e t a l f o r s i z e s up t o 6 f e e t A Equal w e t t i n g by braze a l l o y s of s t r u c t u r e and porous m e t a l 5 Heat t r e a t m e n t o f p r i m a r y s t r u c t u r a l m e t a l 6 C o m p a t i b i l i t y o f braze a l l o y and s e a l a n t impregnated i n t o porous m e t a l 7 I n s p e c t i o n of braze a l l o y J o i n t Adhesive Bonding 1 Decomposition o f p r e s e n t adheslves w i l l contaminate atmosphere o f space v e h i c l e 2 P e n e t r a t i o n o f adhesive i n t o porous m e t a l T h i s w i l l not be as s e r i o u s as w i t h braze a l l o y because o f low modulus of o r g a n i c adheslves 3 C o m p a t i b i l i t y o f adhesive w i t h s e a l a n t impregnated i n t o porous m e t a l 4 I n s p e c t i o n of J o i n t Pressure Bonding 1 E f f e c t o f pressure on porous m e t a l PROPOSED DEVELOPMENT PROGRAM OBJECTIVE Develop method t o a t t a c h porous m e t a l t o s t r u c t u r e f o r use as s e a l on space v e h i c l e BACKGROUND Foamed or f e l t e d n i c k e l and n i c k e l - b a s e a l l o y s may be used f o r the porous metal The porous m e t a l must be a t t a c h e d t o s t r u c t u r a l members t h a t w i l l be made of t i t a n i u m s t e e l or s u p e r a l l o y s t o w i t h s t a n d the temperature a n t i c i p a t e d a t the s e a l T h i s attachment can be by means o f b r a z i n g adhesive bonding or pressure bonding Each process has d i f f e r e n t disadvantages P e n e t r a t i o n o f braze a l l o y i n t o porous m e t a l a n n e a l i n g porous m e t a l i n braze c y c l e t o o l i n g f o r l a r g e s i z e s and i n s p e c t i o n are the major disadvantages o f b r a z i n g P e n e t r a t i o n of an adhesive i n t o the porous m e t a l can be t o l e r a t e d t o a g r e a t e r e x t e n t than w i t h a braze a l l o y so t h a t t h i s i s not one o f the p r i n c i p a l disadvantages o f adhesive bonding Decomposition o f the adhesive l e a d i n g t o p o i s o n i n g o f atmosphere i n space v e h i c l e i s regarded as the major disadvantage o f adhesive bonding Pressure bonding w i l l n o t be a p r a c t i c a l method unless means can be found t o p r e v e n t c o l l a p s e o f porous m e t a l E v a l u a t i o n o f these attachment methods f o r porous m e t a l s i s r e q u i r e d so t h a t the most p r o m i s i n g method can be s e l e c t e d A t t h i s time t h e porous metal s e a l approach should be compared w i t h o t h e r approaches t o c a b i n s e a l i n g so t h a t the program remains o r i e n t e d t o the p r i m a r y g o a l o f a c a b i n s e a l r a t h e r than t o the l i m i t e d o b j e c t i v e o f attachment o f porous m e t a l The f i n a l t a s k i n such a development w i l l be t e s t s o f v a r i o u s s e a l i n g d e v i c e s APPROACH Analyze problems t h a t occur i n attachment o f porous m e t a l t o s t r u c t u r e s and develop s o l u t i o n s t o these problems Examples might be permeation o f braze a l l o y i n t o porous m e t a l which may be stopped by s i n t e r e d i n p l a c e f o i l by s u r f a c e d e n s i f i c a t i o n or by f i l l i n g porous m e t a l w i t h a s u i t a b l e m o l t e n s a l t t h a t can be leached o u t subsequently A second example might be the use o f m o l t e n s a l t i m p r e g n a t i o n t o a l l o w p r e s s u r e bonding 2 E v a l u a t e porous m e t a l bonded by v a r i o u s methods f o r a p p l i c a t i o n as s e a l s Compare the porous m e t a l s e a l w i t h o t h e r s e a l a n t approaches t h a t may be developed 3 S e l e c t a l i m i t e d number o f s e a l a n t approaches and e v a l u a t e i n thorough s e r v i c e type t e s t s Continued on next p«ge
300 INSPECTION TECHNIQUES SUPPLEMEWTAL RECOMMENDATIONS CHART , NO HJQ INSPECTION REQUIRgMKMT End I t e m I n s p e c t i o n o f bond i n t e g r i t y between porous m a t e r i a l s and s o l i d s u b s t r a t e s OBJECTIVE To develop I n s p e c t i o n techniques t o measure (a) porous n i c k e l t h i c k n e s s ( b ) amount o f p o r o s i t y ( c ) v o i d f o r m a t i o n as these m a t e r i a l v a r i a b l e s a f f e c t f a i l u r e o f the porous n i c k e l s e a l a n t I n a d d i t i o n develop acceptance l i m i t s and c a l i b r a t i o n procedures f o r measurement o f bond c o n t i n u i t y base metal/bond f l a w s and bond s t r e n g t h f o r s t a t e o f the a r t t e c h n i q u e s BACKGROUND For e v a l u a t i n g d e n s i t y / p o r o s i t y o f porous n i c k e l bond t o s o l i d s u b s t r a t e i n f r a r e d r a d i o m e t e r techniques (ECB) are a f f e c t e d by p o r o s i t y s i n c e i t a f f e c t s d i f f u s i v i t y The sensor o u t p u t must be c a l i b r a t e d by s t u d y i n g heat f l u x and time o f h e a t i n g t o d e t e c t q u a n t i t a t i v e d i f f e r e n c e s o f p o r o s i t y as a f f e c t e d by s t r u c t u r e and t h i c k n e s s P o r o s i t y a f f e c t s e l a s t i c wave p r o p a g a t i o n and s u r f a c e wave u l t r a s o n i c techniques would be a p p l i c a b l e f o r d e t e c t i n g v o i d s The l i m i t s Imposed by t h i c k n e s s or frequency cannot be p r e d i c t e d u n t i l a l l o w a b l e t h i c k n e s s e s are d e f i n e d P o r o s i t y or d e n s i t y a f f e c t s u l t r a s o n i c resonance (DAC) The l i k e l i h o o d e x i s t s t h a t the porous n i c k e l w i l l e x c e s s i v e l y dampen the i n t e r f a c e echo t h e r e b y p r e v e n t i n g the necessary bond resonance R a d i a t i o n back s c a t t e r a t t e n u a t i o n (BBB) i s a f f e d t e d by d e n s i t y / t h i c k n e s s p r o d u c t so t h a t i f e i t h e r or bot h o f these parameters v a r i e s the change w i l l be sensed Standard f i l m t echniques (BAA) w i l l r e q u i r e q u a n t l t a t l v e i n t e r p r e t a t i o n o f r e s u l t s t o e s t a b l i s h d i f f e r e n c e s i n bond and base metal v o i d s D e n s i t y / p o r o s i t y o f the porous n i c k e l and s o l i d s u b s t r a t e should be e v a l u a t e d b e f o r e bonding t o c o r r e c t l y a s c e r t a i n the degree o f t h i s v a r i a b l e i n the a c t u a l bond The p r e v i o u s l y mentioned techniques would a g a i n be a p p l i c a b l e w i t h i n f r a r e d t e c h n i q u e s no t as l i m i t e d by bond t h i c k n e s s and c o m p o s i t i o n For bond t h i c k n e s s measurements the eddy c u r r e n t (CBA) technique may be a p p l i c a b l e U l t r a s o n i c p u l s e echo (DAA) and resonance (DAC) tec h n i q u e may be used t o d e t e c t the bond or porous n i c k e l / s o l i d s u b s t r a t e t h i c k n e s s However a c o u s t i c v e l o c i t y i n the porous bond areas may not be u n i f o r m p r e v e n t i n g t h i c k n e s s measurements by u l t r a s o n i c t echniques Flaw/crack d e t e c t i o n i n the porous m a t e r i a l s are p o s s i b l e u s i n g SOA tech n i q u e s however c a l i b r a t i o n procedures have t o be developed and q u a n t i t a t i v e acceptance l i m i t s set APPROACH The i n s p e c t i o n e f f o r t s must be c o o r d i n a t e d w i t h the development of the s p e c i f i c bonding process t o e s t a b l i s h s a t i s f a c t o r y I n s p e c t i o n standards f o r v a r i a b l e s which c o n t r o l component l i f e Components which are bonded by the v a r i o u s processes should be t e s t e d by suggested methods t o e s t a b l i s h q u a n t i t a t i v e d i f f e r e n c e s The bonded m a t e r i a l s should be t e s t e d under s e r v i c e c o n d i t i o n s t o e s t a b l i s h q u a n t i t a t i v e l i m i t s on i n s p e c t i o n techniques Of prime Importance i s t o separate the r e l e v a n t from the i r r e l e v a n t m a t e r i a l v a r i a b l e s W i t h the d e s c r i p t i o n o f i n s p e c t i o n problems a v a i l a b l e q u a n t i t a t i v e l y o p t i m i z a t i o n o f techniques should proceed w i t h r e g a r d t o s e n s i t i v i t y r e s o l u t i o n d e t r i m e n t a l and normal d e f e c t i n d i c a t i o n s e t c Upon s e l e c t i o n o f methods o f i n s p e c t i o n and q u a n t i t a t i v e l i m i t s economic f a c t o r s such as d e s i g n and speed may be undertaken Continued on next page
301 APPROACH, c o n t i n u e d CHART NO * / / ^ The above program c o u l d be b r i e f l y d e s c r i b e d as 1 Bond porous n i c k e l Co the s o l i d s u b s t r a t e by any of t h e a p p l i c a b l e processes 2 Use I n s p e c t i o n techniques t o d e t e c t q u a n t i t a t i v e d i f f e r e n c e s I n m a t e r i a l v a r i a b l e s such as bond t h i c k n e s s porous n i c k e l t h i c k n e s s bond/base met a l f l a w s d e n s l t y / p o r o s l t y of base metal and bond 3 P e r f o r m s e r v i c e t e s t s under s e r v i c e c o n d i t i o n s t o e s t a b l i s h q u a n t i t a t i v e l i m i t s on i n s p e c t i o n techniques 4 Optimize I n s p e c t i o n techniques w i t h regard t o s e n s i t i v i t y r e s o l u t i o n c a l i b r a t i o n techniques and l a s t l y economic f a c t o r s
302 PRIORITY RATING W O R K S H E E T CHART P R Q 6 R A M PACTOttfi PROGRAM PBOBABIL ITV OF S U C C E S S ⢠LOW Z ⢠MODERATe 5 HIQH 8 CRITICAL PRpBtEMS TO BE SOtVeO K FCVV/NOT TOO PIFFWULT Z a S O M E / D I F F I C U L T S a M A N Y / VERY D IFF ICULT S G R O W T H P O T E N T I A L V LITTLE OR y N D E F I N A B L E O a eeco&wiPiBLe poreMTiAL 4 OTHER THAN AIR FORCE NONE O SOME 4 MANY e NECESSITY FOR AIR P R O C E S S A P P L I C A T I O N S ⢠FORCe FUNOINO n L O W HI6M IfUttSTttV/CTHtft 6 « r EFF C T If. a MeotnATB - Some EFrotT orHt* ^ousces e NEED FACTORS SYSTEMS PROBABILITY HiaH FTIOBABILITY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y V E R Y HI i 'H HIAH FAIR L o w F R E a U E N C Y OF BEf lU lREMENT IN S Y S T E M M O R E T H A M 3 C O M P O N E N T S 2. 3 CeMPoMENTS S I N G L E C O M P O N E N T OesiSN A L T E R N A T E S No A L T E R N A T E R w e s e E N ONE A L T E R N A T E S E V E R A L A L T E R H I A T E « M A T E R I A L S IMPLICATION New MATERIAL PevtLOf>MeNT RCA 0 MATERIAL IMPlW)VtMeNT Ee<a>p N O P R O B L E M FodtseeM / 2 . 2£ R A W SCORES FOR E A C H COMPONENT IN T A B L W A T L N D O F PANEL RtPotT WITH liAlO E N T E R C P M <3UIUMAeV W S Y S T E M S 3 36 AARP RA>M SCOReS CALCULATE PRIORITY STEP I CIRCLE HIGHEST AARP RAW S C O R E Ms STEP 2 IN EACH OTHER SYSTEM CIRCUE NEXT HIGHEST IF WITHIN 4 POINTS o r TOP SCORE n ^ LOW ^ 33 N U M S E R O F ^ySTEMS HIdH STEP 3 CiRCLe FREOUeNCY DISTRIBUTION FACTOR NUMSen. ov s y i r V M I HIGH SCORE 8 £ t O W i I 3 OS Mote NUMQER OF S Y S T E M * L o w 0 I 2 A MORE (To) 1 z I 4 1 t 1 3 1 1 z 1 «f 1 4 ⢠⢠⢠⢠r i ⢠⢠⢠⢠1â1 ⢠⢠⢠⢠1 1 ⢠⢠⢠⢠1 1 ⢠⢠⢠⢠1 1 ⢠⢠⢠C Z ] 1 1 ⢠⢠⢠e n 1 1 ⢠⢠⢠⢠⢠⢠⢠1 1 ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠C Z 1 1 ⢠⢠⢠[ z : n ⢠⢠⢠⢠1 1 ⢠⢠⢠L _ ⢠⢠⢠L _ ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠p = n » f = TOTAL » 3 3 PRIORITY I E
303 TITLE PRODUCTION OF FLEXIBLE WOVEN METALLIC WIRE STRUCTURES FOR ELEVATED TEMPERATURE SERVICE CHART NO y y 3 PRIORITY RELATED CAMR CHARTS LOX MANUFACTURING REQUIREMENT To produce woven m e t a l l i c w i r e c l o t h s t r u c t u r e s by weaving and J o i n i n g f a b r i c s o f v e r y f i n e (0 002 i n c h ) w i r e s h a v i n g a minimum u l t i m a t e s t r e n g t h o f 100 000 p s l a t 1800 F Both p r e c i p i t a t i o n s t r e n g t h e n i n g and d i s p e r s i o n s t r e n g t h e n i n g s u p e r a l l o y s t o be c o n s i d e r e d S t r u c t u r e s w i t h Be drag chute and f l e x i b l e wing d e v i c e s t o 40 f e e t diameter and 2000 f t 2 I n area AARP REFERENCES E Chert. 156 303 304 305 307 B Cha ts 85a b e 145b 149b 150b PSFVPS Charts APPLICABLE PROCESS RESISTANCE WELDING BONDING One or more o f the f o l l o w i n g depending on end i t e m FUSION WELDING ULTRASONIC WELDING or DIFFUSION C de STATE OF THE ART ASSESSMENT At l e a s t two p r o p r i e t a r y s u p e r a l l o y s have been drawn i n t o w i r e by the a p p l i c a b l e process t o a diameter 0 0002 i n c h i n l e n g t h s o f a p p r o x i m a t e l y s e v e r a l thousand f e e t T h i s has been accomplished i n the l a s t phases o f drawing by r e d u c t i o n s o f a p p r o x i m a t e l y 15 per.,ent per pass and w i t h as many as 20 d i e s I n succession An I m p o r t a n t f a c t o r I s equal r e d u c t i o n and/or drawing f o r c e between successive d i e s S u p e r a l l o y woven me£al f a b r i c w i l l be used on hypersonic f l e x i b l e s t r u c t u r e s because temperatures w i l l exceed the c a p a b i l i t y of p l a s t i c or g l a s s f i b e r weaves I t appears t h a t p r e s e n t day adhesives are c o m p l e t e l y Inadequate f o r the 1800 F requirement Seam welds have been made I n m e t a l l i c c l o t h w i t h a cceptable i n t e g r i t y f o r aerodynamic purposes R e p r o d u c i b i l i t y o f seam welds i n p r o d u c t i o n t o the proper q u a l i t y l e v e l has not been a t t a i n a b l e on a day t o day b a s i s For many f l e x wing a p p l i c a t i o n s the seam weld areas must a l s o be capable o f being formed t o v e r y s m a l l r a d i i and w i t h s t a n d the f l e x i n g a c t i o n p e c u l i a r t o aerodynamic l o a d i n g o f m e t a l l i c f a b r i c s I n g e n e r a l the r e s i s t a n c e seam weld J o i n t s have been u n s a t i s f a c t o r y i n these a p p l i c a t i o n s due t o low d u c t i l i t y and l o s s of f l e x i b i l i t y C o n v e n t i o n a l r e s i s t a n c e w e l d i n g appears t o be t o o c r i t i c a l f o r t h i s a p p l i c a t i o n The c u r r e n t techniques and equipment used f o r the weaving o f s y n t h e t i c f i b e r f a b r i c s as developed by Goodyear and o t h e r s i s c o n s i d e r e d adaptable t o v e r y f i n e m e t a l l i c w i r e s The problem i s t h e n t o combine these methods w i t h j o i n i n g methods f o r w i r e I n t e r s e c t i o n s and seams which w i l l achieve the d e s i r e d geometries o f s u f f i c i e n t l e n g t h and s t r e n g t h CRITICAL PROBLEMS 1 The p r o d u c t i o n o f s u i t a b l e a l l o y w i r e s i n the diameters l e n g t h and s t r e n g t h l e v e l s r e q u i r e d 2 The development o f w i r e weaving t e c h n i q u e s and equipment c o m p a t i b l e w i t h the J o i n i n g process t o be used 3 To p r e s e r v e f l e x i b i l i t y i n t h e J o i n t Welding l e a v e s a weakened heat a f f e c t e d zone and Continued on next page ALTERNATE PROCESSES NONE Code
CHART 304 CRITICAL PROBLEMS, c o n t i n u e d notches where each w i r e J o i n s the r e s i s t a n c e weld nugget The nuggets are r e l a t i v e l y massive compared w i t h the w i r e s ( t y p i c a l l y 0 0002 t o 0 002 i n c h ) so t h a t f l e x i n g o f nuggets i s not p o s s i b l e D i f f u s i o n bonding forms a s i m i l a r c o n s o l i d a t e d area a l t h o u g h heat a f f e c t e d zone damage can be e l i m i n a t e d by s o l i d s t a t e bonding 4 S t r e n g t h o f over 100 000 p s i w i t h 10 per c e n t e l o n g a t i o n i s not a t t a i n a b l e i n c u r r e n t s u p e r a l l o y s Assuming t h i s I s a t t a i n a b l e i n p e r i o d r e q u i r e d r e t e n t i o n o f t h i s s t r e n g t h a t J o i n t s w i l l be a c r i t i c a l problem 5 Design o f J o i n t s t o load a l l w i r e s e q u a l l y w i l l be a c r i t i c a l problem R e t e n t i o n o f 10 p e r c e n t e l o n g a t i o n a t J o i n t w i l l be e s s e n t i a l t o a s s i s t i n load r e d i s t r i b u t i o n between w i r e s PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To produce weld type o f J o i n t s i n woven m e t a l l i c c l o t h made fr o m 0 0002 i n c h diameter p r e c i p i t a t i o n s t r e n g t h e n e d and d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s BACKGROUND Resi s t a n c e seam welds made i n m e t a l l i c c l o t h are u s u a l l y weak or burned w i t h accompanying l o s s i n d u c t i l i t y due t o the v e r y narrow l i m i t s o f pressure and c u r r e n t d e n s i t i e s r e q u i r e d f o r p r o d u c i n g s t r o n g d u c t i l e welds Welds i n v a r i a b l y f a l l when they a r e s u b j e c t e d t o f l e x i n g a c t i o n o f aerodynamic l o a d i n g or when f o r m i n g i s attempted about s m a l l r a d i i F a i l u r e r e s u l t s from s t r e s s c o n c e n t r a t i o n i n t h e weld area r e s u l t i n g from l o s s o f f l e x i b i l i t y o f the welded c l o t h APPROACH 1 Using a r e s i s t a n c e welder as an energy and pressure source i n v e s t i g a t e the f e a s i b i l i t y o f p r o d u c i n g seam type J o i n t s i n m e t a l l i c c l o t h i n b l o c k segments u s i n g low c u r r e n t d e n s i t i e s f o r prolonged time p e r i o d s A slow r i s i n g c u r r e n t wave f o r prolonged p e r i o d s o f time should produce a bond type of J o i n t w i t h minimum pe n e t r a t i o n and b u r n i n g a t the p r o j e c t i o n formed where the w i r e s c r o s s Welding i n b l o c k segments should c o n t r i b u t e t o the e l i m i n a t i o n o f v a r y i n g c u r r e n t d e n s i t i e s caused by non u n i f o r m wheel r o t a t i o n on the m e t a l l i c c l o t h C o n c e i v a b l y i t may be p o s s i b l e t o f a s t e n the m e t a l l i c c l o t h between two copper bars and pass s l o w l y t h r o u g h r o t a t i n g r o l l s u s i n g a low d e n s i t y steady on c u r r e n t R o l l r o t a t i o n on the bars should be u n i f o r m and should achieve the e f f e c t o f a s l o w l y r i s i n g and f a l l i n g wave shape J o i n t s w i t h the r e q u i r e d u l t i m a t e t e n s i l e s t r e n g t h o f 100 000 p s i and e l o n g a t i o n g r e a t e r than 10 per c e n t must be achieved 2 One (1) above may be co n s i d e r e d a form o f d i f f u s i o n bonding and e x p l o r a t i o n should not be c o n f i n e d t o t h i s one approach Both y i e l d d i f f u s i o n bonding and creep c o n t r o l l e d bonding developments should be a p p l i e d t o the p a r t i c u l a r problems of J o i n i n g f i n e w i r e s I t i s obvious t h a t the need here i s p o i n t e d a t the develop ment o f a r a p i d p r o d u c t i o n process f o r making c o u n t l e s s J o i n t s i n l a r g e f l e x i b l e s t r u c t u r e s 3 Other f i e l d s t o be e x p l o r e d are those o f u l t r a s o n i c l a s e r and needle plasma ar c w e l d i n g For these s t u d i e s are r e q u i r e d t o e v a l u a t e a d a p t a b i l i t y t o the s t r u c t u r e s o f d i s c u s s i o n 4 Concurrent w i t h 1 through 3 above i t i s necessary t o a Compare d e s i g n e f f i c i e n c i e s o f f l e x i b l e woven components u s i n g w i r e d i a m e t e r s i n s i z e s from 0 0002 i n c h diameter t o a p p r o x i m a t e l y 0 0005 i n c h diameter T h i s t r a d e study i s i m p o r t a n t s i n c e p r o d u c t i o n o f the s m a l l e s t s i z e s c o u l d e n t a i l c o n s i d e r a b l y more development lead time and expense than 0 0003 i n c h diameter and l a r g e r CAMR Chart 102 should be governed by r e s u l t s o f t h i s t r a d e study Continued on next page
305 NO 7 Y i PROPOSED DEVELOPMENT PROGRAM, c o n t i n u e d b E s t a b l i s h c o n c e p t u a l designs f o r woven J o i n t r e i n f o r c e m e n t s which p r o v i d e e f f i c i e n t l o a d t r a n s f e r t o m e t a l f a b r i c S e l e c t most p r o m i s i n g designs f o r e x p e r i m e n t a l weaving t o v e r i f y adequacy o f pr e s e n t equipment and techniques I n c l u d i n g those f o r s t r a n d i n g s u r f a c e t r e a t m e n t weaving and J o i n i n g by sewing r e s i s t a n c e w e l d i n g d i f f u s i o n bonding adhesive bonding and mechanical f a s t e n i n g c I n c o r p o r a t e most p r o m i s i n g j o i n t designs and J o i n i n g techniques I n t o subscale or f u l l s c a l e p r o t o t y p e hardware 5 The f i n a l phase w i l l be t o i n i t i a t e m a n u f a c t u r i n g development program f o r i n d i v i d u a l process steps where inadequacies are demonstrated
306 PRIORITY RATING W O R K S H E E T CHART PRQgRAM FACTOaS PROGRAM PROBABILITV OF SUCCESS ⢠LOW 2 "JiC MOOERATC 5 ⢠HICH 8 CRITICAL PROBLEMS TO BE SOLVeO n F C ^ / N O T TOO PIFFWULT 7. X SOMe/DIFFICUtT 0 D MANY/ VERY DIFPICUtT 8 PROCeSS GROWTH POTENTIAL ; 4 LirrLE OR UNDEFINA&IC O D ttaoaNiiABte porewTiAL 4 APPLICATIONS OTHER THAN AIR FORCE ⢠NONe o X SOME 4 D MAMY 6 NECESSITY FOR AIR FOgCE FUNOINQ ⢠tow HifiH mtttSTttV/'crHtft <Doyr C F F v i r ^ a ex£uisiyE AIR Fettet FUMONA UKCL>< VL NEED FACTORS S Y S T E M S P R O B A B I L I T Y HI<aH PBOBABH-lTY FAia P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONeNT C R I T I C A L I T Y VERY HICH HIAH F A I R LOW F R E a U C N C Y OF REQUIREMENT IN S Y S T E M MeB£ THAW 3 COMPe^EMTS 4 3 ceMreHEMrs S / N S L E OOMPeWENT O e S \ S N A L T E R M A T E S NO ALTERNATE R I I I E 8 E E N ONC ALTCRMATC S E V E C A L A L T E R U A r e « M A T E R I A L S IMPLICATION Ntw MATEiiiflu peveu'P»<£»'T R e a o jVWTtRlAL IMPftOVEMCIMT R C a O NO pRoe-uEM F o d t s e e n i CALCULATE STEP I STEP a PRIORITY 2 2 . RAW SCo«£S FOR EACH REFCIteMdD CoMPfiNe»/T IH TABLKS AT END OF PAklEl BtP«tT UJITH IIAIO T«>TrtLS ENTCRfP IN A T S Y S T E M S S/A AARP RANN SCO<t£S C I R C L E H I G H E S T AARP RAW S C O R E IN EACH C fTHER S V 6 T E M C IRCLE NEXT HIGMEST SCORE I F W I T H I N ^ P O \ M T S OF TOP S C O R E « HidH ^ LOW ^ STEP 3 NUM6ER OF ^ySTEWS CIRCLE FBEOUENCY DISTRIBUTION FACTOR NUMsen. OP S Y s r c M * Hi&>« I a, 3 OB t*otx. B E L O W i NUMeeR OF S Y S T E M S LOV>< 0 I 2 BMME 1 0 t a I 4 t 3 1 z 1 4 II 1 II 1 II 1 ⢠⢠⢠C l U ⢠⢠⢠⢠] â 1 1 I I I I i n 1 II I I I I 11 1 I L J i n ⢠⢠O E nrn ⢠⢠⢠C 11 1 I L J ! ⢠I L J irn ⢠⢠⢠L 1 ^ o a r II 1 II 1 II 1 II 1 II 1 ⢠⢠⢠⢠⢠⢠⢠⢠⢠⢠] L j n L TOTAL PRIORITY
307 TITLE DIFFUSION BONDING OF TITANIUM ALLOY HONEYCOMB SANDWICH PANELS GRID STIFFENED STRUCTURE AND RIB STIFFENED SKIN PANELS CHART NO PRIORITY RELATED GVMR CHARTS 16 y MANUFACTURING REQUIREMENT To d i f f u s i o n bond t i t a n i u m a l l o y faces (sheet 0 006 i n c h 0 010 i n c h ) t o edge members and honeycomb core ( f o i l 0 001 i n c h - 0 004 i n c h ) f o r heat s h i e l d panels 1/8 i n c h t o 1/A i n c h t h i c k and a p p r o x i m a t e l y 1 f o o t square As an a l t e r n a t e d e s i g n concept t o d i f f u s i o n bond g r i d s t i f fened panels o f the same s i z e made from p l a t e up t o 1/4 i n c h t h i c k Honeycomb panels should be gas t i g h t and o x i d a t i o n r e s i s t a n t a t s e r v i c e temperatures up t o 1000 F and have j o i n t s t r e n g t h s equal t o 80 pe r c e n t or more o f pare n t m e t a l C o n v e n t i o n a l s k i n s t r i n g e r panels or sandwich panels c o u l d a l s o be used f o r l i f t and c o n t r o l r i g i d s k i n and s u b s t r u c t u r e f o r re e n t r y v e h i c l e s up t o 30 f e e t i n diameter but where maximum s e r v i c e temperature does not exceed 400 F T i t a n i u m i s one o f the m a t e r i a l s c o n s i d e r e d f o r l a r g e r e l a t i v e l y t h i c k w a l l s o l i d p r o p e l l a n t r o c k e t chambers D i f f u s i o n bonding might be used f o r components such as "Y r i n g s i n v o l v i n g AARP REFERENCES P r h â , . 116 288 B Chârâ 50a b 134a PftfVPS Châ J o i n i n g NO 13 APPLICABLE PROCESS Code Depending on component e i t h e r (A) PRESS DIFFUSION BONDING or (B) ROLL DIFFUSION BONDING STATE OF THE ART ASSESSMENT Products such as those d e s c r i b e d are c u r r e n t l y being produced i n l a r g e s i z e s o f reasonable q u a l i t y The J o i n t s t r e n g t h r equirements are e a s i l y exceeded Truss core sandwich panels are produced i n s i z e s up t o 80 square f e e t or more by press and r o l l methods R o l l bonding employs I n t e r n a l s t e e l mandrels which are subsequently removed by mechanical and chemical means Honeycomb panels are made by press bonding i n s i m i l a r s i z e s and core c r u s h i n g i s e l i m i n a t e d by t o l e r a n c e and pressure c o n t r o l However none o f the c u r r e n t methods of p r o d u c t i o n can be s a i d t o be a mlniraum c o s t h i g h l y r e l i a b l e process A l l are s u b j e c t t o l a b o r i o u s l a y up procedures and h i g h c o s t t o o l i n g which must be o p t i m i z e d b e f o r e g e n e r a l acceptance i n d e s i g n can be assured CRITICAL PROBLEMS 1 For r o l l bonding l e s s expensive r e t o r t s and mandrels and l e s s c o s t l y mandrel removal are r e q u i r e d 2 Means t o produce c o n v e r g i n g s t i f f e n e r s and tapered s t i f f e n e r s on s t i f f e n e d sheet are r e q u i r e d f o r r o l l bonding 3 Means t o make press bonding a cont i n u o u s process are r e q u i r e d 4 I n s p e c t i o n methods t o assure bond i n t e g r i t y are r e q u i r e d 5 S t r u c t u r a l performance data are r e q u i r e d I n c l u d i n g s t a t i c f a t i g u e and c r a c k s t o p p i n g c h a r a c t e r i s t i c s ALTERNATE PROCESSES NONE Code
308 CHART PROPOSED DEVELOPMENT PROGRAM OBJECTIVE BACKGROUND APPROACH To o p t i m i z e l o l l and press bonding o f t i t a n i u m a l l o y s t o reduce t o o l i n g c o s t s t o produce tapered elements on s t i f f e n e d sheet by r o l l i n g t o develop Improved means f o r mandrel removal a f t e r r o l l bonding and t o develop low c o s t r e l i a b l e I n s p e c t i o n procedures which w i l l assure bond I n t e g r i t y A l s o t o s t u d y means t o develop press bonding as a c o n t i n u o u s process To develop s t r u c t u r a l performance data Rapid p r o g r e s s has been made I n the development o f r o l l and press bonding f o r t i t a n i u m and I n pr o d u c i n g p r o t o t y p e panels and f i t t i n g s f o r a number o f programs I t remains t o o p t i m i z e these processes f o r the p r o d u c t i o n o f s o p h i s t i c a t e d geometries and f o r low c o s t I n s p e c t i o n methods now i n use cannot d i s t i n g u i s h between h i g h s t r e n g t h and low s t r e n g t h bonds 1 The development o f low c o s t r e t o r t s I s r e q u i r e d e l i m i n a t i o n o f r e t o r t s should be s t u d i e d Reusable t o o l i n g and 2 Mandrels should be developed u t i l i z i n g low c o s t m a t e r i a l s and so t h a t c l o s e t o l e r a n c e s can be produced w i t h o u t expensive machining o r s i z i n g o p e r a t i o n s The mandrel m a t e r i a l or mandrel c o a t i n g should be amenable t o easy removal by mechanical chemical or other means 3 The development o f t a p e r i n g d u r i n g r o l l i n g should be aimed a t t a p e r i n g a face sheet s t i f f e n e d by tees tapered I n two d i r e c t i o n s and by r i b s tapered I n h e i g h t and t h i c k n e s s T h i s w i l l r e q u i r e the study of mandrel geometry s t a r t i n g p a r e n t m e t a l geometry and p e r c e n t r e d u c t i o n f o r v a r i o u s c o n f i g u r a t i o n s R o l l t a p e r i n g and/or press bonding combined w i t h taper chemical m i l l i n g should be c o n s i d e r e d Combined taper chemical m i l l i n g and mandrel removal should be c o n s i d e r e d 4 Press bonding as a c o n t i n u o u s process should be s t u d i e d One approach may be t o r e p l a c e c o n v e n t i o n a l press p l a t e n s by l a r g e opposed wheels t h r o u g h which d e t a i l s t o be Joined c o u l d pass I t I s b e l i e v e d t h a t bonds can be achieved I n t h r e e minutes or l e s s which may make t h i s process f e a s i b l e Means o f h e a t i n g and I n e r t l n g are expected t o be c h a l l e n g i n g 5 I n s p e c t i o n processes capable o f d e t e c t i n g low s t r e n g t h bonds I n m a t e r i a l w i t h one or more I n t e r f a c e s are needed These should be r a p i d and low I n c o s t and s u p e r i o r t o the u l t r a s o n i c methods c u r r e n t l y I n use 6 Honeycomb sandwich t r u s s core sandwich and tee s t i f f e n e d panels up t o 2 f e e t X 3 f e e t should be produced and s u b j e c t e d t o s t r u c t u r a l e v a l u a t i o n E v a l u a t i o n should I n c l u d e t e n s i o n compression f a t i g u e and c r a c k s t o p p i n g c h a r a c t e r i s t i c s
309 PRIORITY RATING W O R K S H E E T CHART P R 0 6 R A M PROBABItlTy OF SUCCESS ⢠LOW Z D MODERATE 5 >a. H I G H 8 CRITICAL PROBLEMS TO BE SOLVED U FEVV/NOT TOO DIFFICULT Z ⢠S O M E / D I F F I C U L T 3 M A N Y / VERY D I F F I C U L T A PROCESS GROWTH POTENTIAL ⢠LITTLE OR U N D E F I N A B L E O % g£C06H>llKBie PCTEMTIAL 4 APPLICATIONS OTHER TWAN AIR FORCE ⢠NONE O a SOME 4 >L MANY 6 NECESSITY FOR AIR FOPCE FUNDINO D LOW HifiH iMtustev/jinieft <iovr E F F O I T 4 ^ MooEttATB - soiae Brtotx omce. ^ouaees e ⢠EKcu is i^e AIR Feftct puMPwa LIKCL</ i t NEED FACTORS SYSTEMS PROBABILITY HiaH F^OBABI ITY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T l C A L I T Y VERV HICH HItfiH F/KIR LOW F R E f l U E N C Y OF REQUIREMENT IN S Y S T E M M«tU THAW 3 CoMPaMENTS Z 3 OOMPeMENTS S I N G L E flOMPONENT OesiaN A L T E R M A T E S No ALTERNATe R t a E B E E N ONE ALTEBNATe S E V E R A L A L T E R M A T E e M A T E R I A L S IMPLICATION New MATefeifli. ptvtu)(>M£NT izeek o M A T t B l A L M P I U J V t M C M T E E O D NO PROBLEM r o R c s e e u 12 8 4 I I 9 3 3 2 I 9 6 3 6 4- O CALCULATE PRIORITY e 8 e RAW sco«es Foe. EACH REFeeexou> CoMWNttfT IN TABLES AT LND OF PAUet UtpOtT WITH TOT ^LS ENteacp nu /HT A A R P RAVyi SCoRCS /I 3c I 2o 11 11 11 / </^r2jl?gT)l II 1Ì g / / ' II II SZA I g ^ l II 1Ì 1^1 II II STEP I STEP 2 STEP 3 CIRCLE HIGHEST AARP RAW SCORE n : IN E-ACH CTTHER SVeTEM CIRCLE NEXT HiaMEST SCORE IP WITHIN 4 POINTS o r TOP SCORE NUMBER O F SySTEIWS H idH L O W 2 CIRCLE FBEOUENCY DISTRIBUTION FACTOR NUMsen. Of SySTfiMS 1 2. 3 OR MKtLE N U M & E R . 0 OF S Y S T E M S 1 L O W 1 0 1 a 1 4 1 1 1 3 1 *f 2 R Mooe 1 2. 1 *f B£LOWt ⢠⢠TOTAL PRIORITY
-310 TITLE DIFFUSION BONDING OF TANTALUM AND TUNGSTEN ALLOYS CHART PRIORITY ^ RELATED CAMR CHARTSi MANUFACTURING REQUIREMENT To d i f f u s i o n bond t a n t a l u m a l l o y C and D s e c t i o n h o l l o w shapes w i t h I n t e r n a l s t i f f e n i n g angles r i b s and doublers and t u n g s t e n a l l o y h o l l o w h e m i s p h e r i c a l or c o n i c a l shapes a l s o w i t h i n t e r i o r s t i f f e n i n g r i n g s angles and d o u b l e r s Diameters from 6 inches t o 12 Inches w i t h t o l e r a n c e o f + 0 01 In c h Nose r a d i i f o r cones o f 0 5 In c h t o 3 0 Inch Sheet me t a l t h i c k n e s s t o 0 OAO i n c h For p r o p u l s i o n systems a p p l i c a t i o n s i n v o l v e t u b i n g f o r heat exchangers and sheet f o r d l f f u s e r l e a d i n g edges and contoured s u r f a c e s of vanes combustion chambers and a f t e r b u r n e r s i n s i z e s up t o 6 f e e t diameter x 13 f e e t long AARP REFERENCES E Cha »s fLL 61 64 91 96 273 B Chots. 28d, 29c. d, 39c d, AOc. d, 123 P4FVPS Chart. J o i n i n g No 8, 10, 11 APPLICABLE PROCESS YIELD STRENGTH CONTROLLED DIFFUSION BONDING ( u s i n g h i g h pressure and s h o r t t i m e ) or CREEP CONTROLLED DIFFUSION BONDING (us i n g low pressure & long time)! Code 6 09 01 6 09 02 STATE OF THE ART ASSESSMENT Y i e l d S t r e n g t h C o n t r o l l e d D i f f u s i o n Bonding Tantalum a l l o y s t r e n g t h c o n t r o l l e d gauges Cleaning a Bonding temperature m e t a l s t r e n g t h by to show process fea u t i l i z e d as w e l l as have a l s o been used f o r t h i s process s have been d i f f u s i o n bonded on a developmental b a s i s using l o c a l i z e d y i e l d process and gas pressure bonding l i m i t e d to s m a l l t e s t specimens and nd s u r f a c e p r e p a r a t i o n i s c r i t i c a l f o r p r o d u c i n g good J o i n t s t r e n g t h s o f 2600F and 2h 000 p s i pressure w i t h I n t e r f o i l s ^ produced J o i n t s o f par e n t y i e l d c o n t r o l l e d process Small p r o t o t y p e s t r u c t u r e s have been f a b r i c a t e d s l b i l l t y I n t e r m e d i a t e f o i l s such as t i t a n i u m and t a n t a l u m have been s e l f bonding Other i n t e r m e d i a t e f o i l s such as columblum and vanadium i n bonding t a n t a l u m and i t s a l l o y s No experience w i t h t u n g s t e n I s known Creep C o n t r o l l e d D i f f u s i o n Bonding Gas pressure bonding o f t a n t a l u m a t 2900F and 10 000 p s i a l s o produced e q u i v a l e n t j o i n t t engch but the longer cy l e e ulced i n dec ca ed d u c t i l i t y of the par e n t m a t e r i a l Tantalun| I n t e r m e d i a t e m a t e r i a l has shown Improved s t a b i l i t y a f t e r d i f f u s i o n heat t r e a t and s t r e s s r u p t u r e t e s t s over vanadium and columbium i n t e r f o l l s Tungsten has been d i f f u s i o n bonded on a developmental b a s i s u s i n g creep c o n t r o l l e d processes however the work has been l i m i t e d t o sm a l l t e s t specimens and gauges I n t e r mediate m a t e r i a l s o f molybdenum t a n t a l u m columbium and vanadium have been used w i t h f a i r success Times r a n g i n g as long as 54 and 72 hours have been used t o bond t u n g s t e n t e s t p i e c e s Tungsten a l l o y (W 26/ Re) i s c u r r e n t l y being produced and t h e r e f o r e v e r y l i m i t e d bonding has been performed High temperature t e s t s and c o m p a t i b i l i t y o f v a r i o u s o x i d a t i o n r e s i s t a n t c o a t i n g s w i t h t u n g s t e n and i n t e r m e d i a t e m a t e r i a l s are c u r r e n t l y being e v a l u a t e d For both processes NDT techniques r e q u i r e Improvement Continued on next page ALTERNATE PROCESSES NONE Code
311 NO T J g ^ CRITICAL PROBLEMS 1 C a p a b i l i t y of d i f f u s i o n bonding processes equipment and t o o l i n g t o p r o v i d e j o i n t a c c e s s i b i l i t y and t o produce the s t r u c t u r a l shape t o the r e q u i r e d t o l e r a n c e w i t h o u t excessive d e f o r m a t i o n w i t h i n the bonding parameters o f temperature pressure and time 2 C o n t r o l of c l e a n i n g and s u r f a c e p r e p a r a t i o n t o p r o v i d e u n i f o r m bonding 3 Atmosphere c o n t r o l d u r i n g bonding t o prevent c o n t a m i n a t i o n d u r i n g l o c a l i z e d bonding 4 Degradation o f m a t e r i a l p r o p e r t i e s a s s o c i a t e d w i t h long bonding c y c l e s 5 C o m p a t i b i l i t y o f i n t e r m e d i a t e m a t e r i a l s w i t h o x i d a t i o n r e s i s t a n t c o a t i n g s and processings 6 Degradation of m a t e r i a l p r o p e r t i e s by i n t e r m e d i a t e m a t e r i a l s d u r i n g p r o c e s s i n g or subsequent s e r v i c e 7 Removal of t o o l i n g m a t e r i a l s a f t e r bonding 8 Inadequacy o f p r e s e n t NOT methods t o d e t e c t degree of p a r t i a l bonds PROPOSED DEVELOPMENT PROGRAM OBJECIIVE BACKGROUND APPROACH To develop p r o c e s s i n g data on the d i f f u s i o n bonding o f t u n g s t e n a l l o y s e s t a b l i s h i n g the e x t e n t t o which t u n g s t e n can be bonded by both y i e l d s t r e n g t h and creep c o n t r o l l e d processes To extend the d i f f u s i o n bonding c a p a b i l i t i e s f o r t a n t a l u m a l l o y s by g e n e r a t i n g a d d i t i o n a l p r o c e s s i n g data f o r both y i e l d s t r e n g t h and creep c o n t r o l l e d processes and process v e r i f i c a t i o n by p r o t o t y p e hardware f a b r i c a t i o n and e v a l u a t i o n The b r i t t l e n e s s o f t u n g s t e n and i t s d i f f u s i o n bonded J o i n t s which can become more severe i n s e r v i c e i s viewed as a d e t e r r e n t t o i t s use compared t o a l t e r n a t e m a t e r i a l s More i n f o r m a t i o n on the m e r i t s and disadvantages o f i n d i v i d u a l techniques i s d e s i r e d i n c l u d i n g f a b r i c a t i o n of subscale components i n c o r p o r a t i n g t y p i c a l design c o m p l e x i t i e s such as edge members l o c a l attachment p o i n t s e t c E f f o r t should be paced by how p r o m i s i n g t u n g s t e n components prove t o be i n r e l a t i o n t o a l t e r n a t e m a t e r i a l s The p o t e n t i a l u s e f u l n e s s o f t a n t a l u m a l l o y s appears s u f f i c i e n t l y ensured t h a t f u r t h e r advancement o f the d i f f u s i o n bonding techniques i s warranted to demonstrate d e s i g n v e r s a t i l i t y and p r o v i d e c o n f i d e n c e o f minimum r i s k t o using v e h i c l e s and systems 1 Determine the f e a s i b i l i t y o f producing c l o s e t o l e r a n c e s t r u c t u r a l shapes f o r t u n g s t e n and t a n t a l u m a l l o y s w i t h o u t excessive d e f o r m a t i o n by both creep c o n t r o l l e d and y i e l d s t r e n g t h c o n t r o l l e d processes These processes could combine l o c a l i z e d j o i n i n g processes such as spot bonding and gas pressure or press bonding techniques depending upon c o n f i g u r a t i o n o f the p a r t J o i n t d e s i g n and a c c e s s i b i l i t y Determine bonding temperature time and pressure s u r f a c e p r e p a r a t i o n techniques and i n t e r mediate m a t e r i a l r equirements t o produce d i f f u s i o n bonded J o i n t s between honeycomb core and face sheets u s i n g creep c o n t r o l l e d methods of low pressure and long time t o prevent panel damage 2 Develop equipment and t o o l i n g m a t e r i a l s which w i l l p r o v i d e r e l i a b l e atmospheric c o n t r o l d u r i n g bonding T h i s I n c l u d e s chambers f o r l o c a l i z e d bonding and encapsulat i n g m a t e r i a l s and t o o l i n g capable of h i g h temperatures pressures and long times r e q u i r e d f o r creep bonding processes 3 Determine the e f f e c t of creep c o n t r o l l e d bonding processes i n v o l v i n g low pressures and long time a t temperature on r e f r a c t o r y m e t a l p r o p e r t i e s and j o i n t s t r e n g t h and the use o f i n t e r m e d i a t e m a t e r i a l s t o reduce bonding pressure and temperature ^ o n i ^ n u e ^ ^ r w i e x ^ ^ a g ^
-312- NO y 3 A PROPOSED DEVELOPMEWr PROGRAM, co n t i n u e d A Determine f i t up t o l e r a n c e s and s u r f a c e f i n i s h e s necessary t o produce the f i n a l p a r t c o n f i g u r a t i o n and dimensions 5 E s t a b l i s h methods f o r removal o f t o o l i n g by mechanical or chemical means which w i l l not degrade the p a r t 6 Determine the e f f e c t o f the bonding c y c l e t o o l i n g m a t e r i a l s f o r m i n g process and t o o l removal methods on J o i n t s t r e n g t h and p a r e n t m e t a l p r o p e r t i e s 7 Determine the e f f e c t o f o x i d a t i o n r e s i s t a n t c o a t i n g s and processes on I n t e r m e d i a t e m a t e r i a l s and j o i n t s t r e n g t h
313 PRIORITY RATING W O R K S H E E T CHART PR06RAM PROBABIL ITY OF S U C C E S S D LOW Z ⢠MODERATE 5 > t HiaH 8 C R I T I C A L P R O B L E M S TO B E SOLVED a F E W / N O T TOO PIFFWULT Z S O M E / D I F F I C U L T 0 Q M A N Y / VERY DIFF ICULT 8 G R O W T H P O T E N T I A L » LITTLE OR U N D E F I N A B L E O ⢠KEC06NIIABLE PorEMTIAL 4 OTHER THAN AIR FORCE NONE O SOME 4 MANY e FOR AIR FORCe FUNOIKiO PROCESS APPLICATIONS ⢠a NECESSITY n l o w HiaH mtUSIttV/'cTHta <3«r EFF i T ^ X MePCSATE - SOME EFroiLT orHCK ^aio^es a O t t t W S i v E A IR Foftet FUWpM<i LiKCL-/ 14. p = NEED FACTORS SYSTEMS PROBABILITY HiaH PROBAei ITY FAIR P R O B A B I L I T Y LOW P R O B A B I L I T Y COMPONENT C R I T I C A L I T Y VERY H K S H HIAH F A I R L o w F R E Q U E N C Y OF REQUIREMENT IN - S Y S T E M MORE THAN 3 COMPeNEHlTS Z 3 eOMI^ONENTS S I N G L E COMPONtUT D E S \ S N A L T E R M A T E S No ALTERNATE f t W E S E E N ONE ALTERNATE S E V E R A L A L T E R N A T E * M A T E R I A L S IMPLICATION New MATEe.lAU P£.VtU>PMENT CfO) O (vWTERiAL iMPftovtMtWT e e a P NO P R O a L E M F o U C S E e N CALCULATE STEP I STEP Z PRIORITY 8 8 RAW s c o p e s F O R EACM IZEFeBENCtP COMPtfNrNT IH T A B LM AT E N D OF PANEL IJtpOtT IflTH B A W Te>T«LS ENTEREP IN <3UMMflEV W S Y S T E M S /9 3i, AARP RAVJ SeoRCS i ^ i z a a n n o /ÌÌ [^imi I ^ 1 ^ 1 II 1Ì 8 /m\^Y3^\ IÌ g.^*' ^ j f i T I f i in I 11 S3ek CIRCLE HIGHEST AARP RAW S C O R E IN EACH OTHER SYSTEM CIRCLE NEXT HICMEST IF WITHIN 4 POINTS OF TOP SCORE \ i NUMBER OF SYSTEMS HldH ^ ' ^ LOW STEP 3 CIRCLE FREQUENCY DISTRIBUTION FACTOR NuMsen. OP sysTCMf H I G H SCORE BEUSWt 3 OR MOCE NUMBER OF S Y S T e w s LOV^ 2 R. Moae 1 0 1 & 1 4 1 1 t 3 1 z 1 4 i n f z ^ f i ^ i II 2i I I Z D I TOTAL PRIORITY
314- TITl£ RADIATION CURING OF ADHESIVE BONDED COMPONENTS MANUFACTURING REQUIREMENT CHART PRIORITY REUTED CAMR CHARTSi 703. To bond s t r u c t u r e s w i t h o u t a p p l i c a t i o n o f heat and t o c o n t r o l s h e l f l i f e o f r e e l n s and adhesives Process must be r a p i d and p r o v i d e s i g n i f i c a n t l y Improved p r o p e r t i e s o f s t r e n g t h and temperature over cement adhesives Process must be r e p r o d u c i b l e T a r g e t s t r e n g t h i s 5000 p s l a t 700 F AARP REFERENCES E Charts 153. 154, 178 B Charts. 84, 95a 96 98c P4FVPS Charts. APPLICABLE PROCESS ADHESIVE BONDING STATE OF THE ART ASSESSMENT Code 6 08 06 Presen t h i g h s t r e n g t h adhesive bonding processes r e q u i r e c l o s e c o n t r o l o f pre s s u r e temperature and time t o achieve optimum p r o p e r t i e s I n a d d i t i o n f o r m u l a t i o n s are c r i t i c a l a t a l l stages f r o m m i l l i n g r e d i e n t s t o f i n a l p r o d u c t and these Impose f u r t h e r l i m i t s on time a v a i l a b l e f o r p r o c e s s i n g Use o f h i g h temperatures f o r c u r i n g causes problems because o f d i f f e r e n t i a l expansion o f t o o l i n g and m a t e r i a l s and because o f o u t g a s s i n g o f r e s i n and adhesive f o r m u l a t i o n s C a p i t a l equipment investments are h i g h w i t h p r e s e n t methods CRITICAL PROBLEMS 1 H e a t i n g under c o n t r o l l e d c y c l e s o f l a r g e s t r u c t u r e s i s d i f f i c u l t t o c o n t r o l when h e a t i n g i s t h r o u g h t o o l s and posts T h i s becomes a major problem i n p r o d u c t i o n w i t h m u l t i p l e c y c l e s 2 S h e l f l i f e o f r e s i n or adhesive l i m i t s f a b r i c a t i o n c y c l e time T h i s becomes i n c r e a s i n g l y i m p o r t a n t f o r l a r g e s t r u c t u r e s 3 Composition i s l i m i t e d by cho i c e o f c a t a l y s t s t h a t may degrade p r o p e r t i e s by o u t g a s s i n g 4 Cu r i n g times and c y c l e s are exc e s s i v e ALTERNATE PROCESSES NONE Code
315 CHART PROPOSED DEVELOPMENT PROGRAM OBJECTIVES To develop a bonding system t h a t i n c l u d e s c o m p o s i t i o n s and c u r i n g equipment f o r r a p i d room temperature bonding To achieve h i g h r e l i a b i l i t y bonds i n a sim p l e c u r e c y c l e BACKGROUND Use o f bonded s t r u c t u r e s and a n t i c i p a t e d use o f advanced composite m a t e r i a l s i s s t r o n g l y dependent on c o s t and r e l i a b i l i t y The p r e s e n t p o s i t i o n i s summarized under the S t a t e o f the A r t Assessment Recent developments I n c u r i n g r e s i n bonded p a i n t s p o l y e s t e r laminates and epoxy systems by means o f h i g h energy bombardment has opened new approaches I n t h i s f i e l d A l t h o u g h the development I s r e c e n t demonstrated and a n t i c i p a t e d advantages are numerous These i n c l u d e a b i l i t y t o cure a t room temperature improved p r o p e r t i e a b i l i t y t o supply energy d i r e c t l y t o r e s i n r a t h e r t h a n by heat c o n d u c t i o n through t o o l i n g r a p i d c u r i n g and new p o s s i b i l i t i e s I n r e s i n c h e m i s t r y APPROACH I t i s recommended t h a t a program be s t a r t e d t o examine the p o t e n t i a l o f h i g h energy bombardment as a c u r i n g method f o r aerospace components T h i s w i l l i n v o l v e m a t e r i a l development as w e l l as system development and p r o d u c t i o n o f d e m o n s t r a t i o n hardware A t h r e e phase program i s proposed Phase I Study m a t e r i a l systems Steps i n t h i s w i l l i n v o l v e s t u d i e s o f I n t e r a c t i o n between r a d i a t i o n and adhesives or r e s i n s based on p r e s e n t l y a v a i l a b l e c h e m i s t r i e s M o d i f i c a t i o n o f pre s e n t adhesives t o i n t e r a c t w i t h r a d i a t i o n and o b t a i n c u r i n g times o f l e s s than one minute and p r e f e r a b l y l e s s than one second Phase I I Apply process t o j o i n t s and lam i n a t e s Complete e v a l u a t i o n of r a d i a t i o n cured adhesives and lam i n a t e s should be conducted on l a b o r a t o r y s i z e d samples t o determine p r o p e r t i e s These p r o p e r t i e s should be compared w i t h c o n v e n t i o n a l l y cured adhesives and laminates Phase I I I Demonstration hardware Selected components and s t r u c t u r e s should be f a b r i c a t e d by heat cure and r a d i a t i o n cure methods These w i l l be g i v e n s i m u l a t e d s e r v i c e t e s t s t o e v a l u a t e p o t e n t i a l of t h i s cure method Equipment development should accompany t h i s phase
3 1 6 PRIORITY RATING WORKSHEET CHART P R O S R A M PACTORS PROGRAM PCOBABILITV OF SUCCESS D L O W Z ⢠MODERATe 5 >9, HI<aH 8 C R I T I C A L P R O B L E M S TO B E SOLVeO ^ F e \ ^ / N O T TOO DIFFWUtT Z ⢠3 0 M e / D I F F I C U L T S a M A N Y / V E R Y D I F F I C U L T 8 P R O C E S S G R O W T H P O T E N T I A L ⢠LITTLE OR. UNDEFINABLE O y(, (JKOaNllABLE poreUTIAL 4 A P P L I C A T I O N S O T H E R T H A N AIR F O R C E a NONE 0 >C SOME 4 D MANY a N E C E S S I T Y F O R A I R F O R C E F U N i D I N O ⢠L O W HI6H |MtUSTaV/cirH£« G«r C F F 4 T If- yi^ pHOOtttATB - Smc BfrotX OTHce. â¢SDU«fl£9 6 a EX£UJ5We A IR F e l l C t F U W P M S L I K C L ' / 14. N E E D F A C T O R S S Y S T E M S P R O B A B I L I T Y KiaH PBOBABI ITY FAIR PROBABILITY LOW PROBABILITY COMPONENT CRITICALITY VERY HKTH HI&H F A I R LOW F R E a U E N C Y O F R E Q U I R E M E N T IN S Y S T E M MARE THAN 3 COMPeHEMTS 2 . 3 c e M P e U E n r s s i N f l L E C O M P O N E N T OeSiaN ALTeRMAiTES No ALTESNATE R 0 O 6 B E E N ONE AUTERNATE SEVEB.AL ALTERWAre« MATERIALS IMPLICATION New MATEClflL PEVtLOfHieNT CCA O MATERIAL IMPftOVEMENT EE<9 D NO PROBLEM FoftCSCeKl IZ 8 I Z 9 & 3 3 2 I 6 3 6 4 o CALCULATE P R I O R I T Y e 8 Z6 RAW sco«es F O R EACH CEFESeXflP COMWNttfT IN TABLM AT END o r PAUEt R t P « t T W I T H IJAW T o T t t L S ENTEREP IN <3UIU>(AtV /XT A A R P RA>M s c o a e s STEP I STEP 2 IF WITHIN 4 POINTS NUMBER OF â¢SVSTEMS HldH OF TOP S C O R E 3S CIRCLE HIQHCST AARP RAW S C O R E IN EACH CTTHER SYSTEM CIRCLE NEXT MKSI4EST SCORE n LOW STEP 3 CIRCLE FREQUENCY DISTRIBUTION FACTOR f BELOWt NUMQen. OP s y s r C M « I 2 NUMacR. OF SVSTEMS LOW 2 R Mooe H a>4 3 OK i w a e t o 1 i. 1 4 1 3 1 V \ 2. 1 «f 1 4 ? 5 3£S ⢠⢠E I ⢠⢠⢠⢠⢠⢠⢠⢠TOTAL PRIORITY
317 AARP REFERENCES P rhâ». 67 68 96 97 282 R ri,â 28c d 29a b c 30d e 31a 39c d 40c d A l e 133a b c paFVPi rhnrt« APPLICABLE PROCESS MECHANICAL FASTENING Code 6 11 00 TITLE MECHANICAL FASTENING OF METALLIC AND NGN METALLIC COMPONENTS FOR ELEVATED TEMPERATURE SERVICE CHART NO PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Mechanical f a s t e n i n g syscems are r e q u i r e d f o r attachment o f a b l a t o r and ceramic t h e r m a l p r o t e c t i o n s h i e l d s f o r non m e t a l l i c radomes and m e t a l l i c heat s h i e l d s j o i n e d t o m e t a l l i c s u b s t r u c t u r e s The attachment scheme must mi n i m i z e s t r e s s c o n c e n t r a t i o n s from e i t h e r i n s t a l l a t l o n or the t h e r m a l environment Fasteners must p r o v i d e minimum heat p a t h t o the support s t r u c t u r e and must operate r e l i a b l y a t the e l e v a t e d s e r v i c e temperature and under the o x i d i z i n g environment s p e c i f i c t o each component M u l t i p l e f l i g h t c a p a b i l i t i e s are expected and i n some i n s t a n c e s attachment schemes i n v o l v i n g f a s t e n e r removal and r e i n s t a l l a t i o n are r e q u i r e d STATE OF THE ART ASSESSMENT Mechanical F a s t e n i n g up t o 3000 F Mechanical f a s t e n e r s f o r s e r v i c e up t o 3000F r a n g i n g from r i v e t s t o unique f a s t e n e r shapes can be produced w i t h s t a t e o f the a r t c a p a b i l i t i e s from such m a t e r i a l s as the c o l d worked n i c k e l base a l l o y s t o columbium and t a n t a l u m base a l l o y s There i s however an i n a b i l i t y t o m a i n t a i n adequate o x i d a t i o n p r o t e c t i o n above about 20001? and f u r t h e r c o a t i n g s development work I s needed Fastener manufacturers see l i t t l e d i f f i c u l t y I n d e v e l o p i n g unique shapes I n c o r p o r a t i n g deformable f e a t u r e s f o r b l i n d and semi b l i n d i n s t a l l a t i o n s i f d u c t i l e c o a t i n g s or o t h e r means f o r a c h i e v i n g o x i d a t i o n p r o t e c t i o n c o u l d be p r o v i d e d Refurbishment i s p r i m a r i l y l i m i t e d by c o a t i n g s c a p a b i l i t i e s w i t h a need f o r minimum r e a c t i o n w i t h mating p a r t s t o ensure disassembly f o r i n s p e c t i o n and rework and a need f o r r e p a i r or pa t c h c o a t i n g s f o r l o c a l i z e d use t o remedy damage from i n s t a l l a t i o n or s e r v i c e To s i d e s t e p some of these d e f i c i e n c i e s p l a t i n u m a l l o y deformable f a s t e n e r s have been adopted f o r some s t r u c t u r e s r e s e a r c h s t u d i e s because o f the r i n h e r e n t d u c t i l i t y and o x i d a t i o n r e s i s t a n c e A secondary problem which l i m i t s the use of p l a t l n j m and n i c k e l a l l o y s I n a p p l i c a t i o n s where s i l i c i d e c o a t i n g s are r e q u i r e d f o r o t h e r d e t a i l s i n the assembly i s the r a p i d f o r m a t i o n o f low m e l t i n g s i l i c i d e e u t e c t i c s Mechanical F a s t e n i n g above 3000 F Tungsten and t a n t a l u m a l l o y f a s t e n e r s have been used I n e x p e r i m e n t a l q u a n t i t i e s f o r s e r v i c e above 3000F but o x i d a t i o n p r o t e c t i o n c o a t i n g s do not meet requirements so t h a t u n t i l adequate p r o t e c t i o n i s p o s s i b l e t h e r e i s l i t t l e reason t o e x p l o i t f a s t e n e r m a n u f a c t u r i n g c a p a b i l i t i e s Emphasis i n design has t h e r e f o r e been t o exclude the f a s t e n e r attachment system from the most severe thermal and o x i d i z i n g environment recessed under a b l a t i v e o v e r l a y s or plugs For most a p p l i c a t i o n s the h i g h d e n s i t y o f t u n g s t e n and t a n t a l u m f a s t e n e r s i s a d e t e r r e n t when they would be used i n q u a n t i t y adding y e t another reason t o seek o t h e r d e s i g n a l t e r n a t e s A l t h o u g h not an attachment method I n the usual sense i r i d i u m w l r e h a s been used f o r r e i n f o r c i n g cement heat s h i e l d s and p r o v i d i n g attachment t o the s u b s t r u c t u r e I r i d i u m has s e v e r a l disadvantages because o f i t s b r i t t l e n e s s l i m i t e d supply h i g h c o s t and o n l y Continued on nex t page ALTERNATE PROCESSES NONE Code
CHART 318 STATE OF THE ART ASSESSMENT, c o n t i n u e d moderate o x i d a t i o n r e s i s t a n c e Non m e t a l l i c t e n s i o n and shear f a s t e n e r s made from ceramics g r a p h i t e and g r a p h i t i c composites d e r i v e d from r e i n f o r c e d p l a s t i c p r e c u r s o r s have been i n v e s t i g a t e d on a l i m i t e d s c a l e f o r low load a p p l i c a t i o n s Alumina r e t e n t i o n c o l l a r s were f o r m e d - i n p l a c e around the shank o f z i r c o n i a p i n s by flame s p r a y i n g t o p r o v i d e a mechanical attachment scheme f o r s e c u r i n g ceramic i n s u l a t i o n onto the s t r u c t u r a l g r a p h i t e s h e l l f o r the X 20 nose cap CRITICAL PROBLEMS 1 Development o f new m a t e r i a l s systems ( s u b s t r a t e and c o a t i n g ) f o r use above about 2000 F Several d i f f e r e n t g o a l s should be e s t a b l i s h e d based on component requirement which can be d e r i v e d from AARP r e f e r e n c e s ( s e r v i c e temperature l i f e s t r e s s l e v e l s t h e r m a l c y c l i n g ) Develop f a s t e n e r and o x i d a t i o n p r o t e c t i o n scheme as an e n t i t y Need f o r new concepts t o broaden h i g h temperature mechanical f a s t e n i n g d e s i g n c h o i c e s w i t h i n the l i m i t a t i o n s o f c u r r e n t m a t e r i a l s development progresses Extend c o n c e p t u a l d e s i g n study as m a t e r i a l s PROPOSED DEVELOPMENT PROGRAM OBJECTIVE To develop a d d i t i o n a l mechanical attachment techniques and a s s o c i a t e d hardware f o r t y p i c a l components f o r e l e v a t e d temperature s e r v i c e APPROACH 1 Mechanical attachment problems encountered f o r v a r i o u s h o t s t r u c t u r e s programs should be re examined t o determine the p e n a l t i e s a s s o c i a t e d w i t h the d e s i g n s o l u t i o n s f i n a l l y accepted and the design a l t e r n a t e s e v a l u a t e d Such programs I n c l u d e ASSET Prime X 20 Snap R e p r e s e n t a t i v e d e s i g n problems should be s e l e c t e d f o r r e st u d y w i t h the o b j e c t i v e o f d e f i n i n g a l t e r n a t e attachment hardware and I n s t a l l a t i o n t echniques T h i s e f f o r t might take the form o f s m a l l c o n t r a c t e f f o r t s f o r r e s t u d y and problem d e f i n i t i o n Those examples where p r o m i s i n g a l t e r n a t e mechanical attachment schemes can be p o s t u l a t e d from knowledge of s p e c i f i c d e s i g n c r i t e r i a and l o c a l environment should be s e l e c t e d f o r t r i a l f a b r i c a t i o n i n c l u d i n g manufacture o f any unique f a s t e n e r concepts S e c t i o n s o f p r o t o t y p e hardware should be assembled and t e s t e d P r i m a r y requirement i s t h a t components be removable f o r replacement and/or r e p a i r 2 Advances i n c o a t i n g s c a p a b i l i t i e s from the recommended m a t e r i a l s development hould be I n t r o d u c e d i n p r o c e s s i n g and p r o t o t y p e hardware development programs as they become a v a i l a b l e Coatings should be capable o f w i t h s t a n d i n g s e v e r a l removals o f f a s t e n e r s or o f being r e a d i l y renewed 3 S p e c i f i c a t t e n t i o n i s suggested t o promote development o f non m e t a l l i c attachment schemes I n c o r p o r a t i n g e i t h e r i n t r i n s i c o x i d a t i o n r e s i s t a n c e or c o n s t i t u e n t s which p r o v i d e o x i d a t i o n r e s i s t a n c e by i n s i t u r e a c t i o n s i n s e r v i c e The j o i n t problem f o r h i temperature extended s e r v i c e i s unique The need f o r t i g h t J o i n t s f o r maximum shear f a t i g u e l i f e and s e a l i n g I s combated by b r i t t l e m a t e r i a l s i n which c l o s e f i t s cause c r a c k i n g and premature f a i l u r e C o n v e n t i o n a l r i v e t i n g and t o r q u i n g techniques cannot be used f o r the same reasons Rapid c o r r o s i o n occurs between some d i s s i m i l a r metals i n the d e s c r i b e d c y c l i c environment Selected f a s t e n e r and j o i n t designs must be s u b j e c t e d t o son i c and s t r u c t u r a l f a t i g u e t e s t s u s i n g v a r i o u s a t t a c h methods as w e l l as an e v a l u a t i o n o f c o r r o s i o n c h a r a c t e r i s t i c s under temperature r e c y c l i n g
3 1 9 PRIORITY RATING WORKSHEET CHART PRQgRAM FACTORS P B O f i R A M P R O B A B I L I T Y O F S U C C E S S a LOW z ⢠MooenATE 5 ;ttf H I G H 8 C R I T I C A L P R O B L E M S TO B E S O L V E D K F E \ ^ / N O T TOO D I F F W U L T Z ⢠S O M E / D I F F I C U L T 3 a M A N Y / V E R Y D I F F I C U L T 8 G R O W T H P O T E N T I A L ⢠L I T T L E OR U N D E F I N A B L E O K flECO&Hlll^Bie p o r E M T I A L 4 O T H E R T H A N AIR F O R C E NONE O S O M E 4 M A N Y e FOR AIR FORCE FUNDING PRocess A P P L I C A T I O N S n ⢠NECESSITY >tf LOW HI6H iNjttSTev/OTHeft 6 w r E F F ax t a M'DiUfiTE - Some E F P o t r oriteR « o u « t f £ s s Q tlCCUtSWe AlR F e f t e t F U N D Ma LIKCLi< 14. N E E D FACTORS SYSTEMS PROBABILITY HIOH F T W B A e i L l T Y F A i a P R O B A B I L I T Y L O W P R O B A B I L I T Y C O M P O N E N T C R I T I C A L I T Y V E R Y H K T H H I A H F A I R L O W F R E C J U E N C Y O F R E Q U I R E M E N T IN S Y S T E M MORE THAW 3 C O M P O N E N T S Z 3 C e w P e M E N T S S I N G L E C o M P e N E N T D E S I G N A L T E R N A T E S No A L T E R N A T E R M t E e E E N ONE A U T E R N A T S S E V E B . A L A L T E R M A T E C M A T E R I A L S I M P L K J A T I O N N e w M A T E R I A L P t V t l O f M E N T C C H O jVMTtBiAL iMPftovtMCNT ee<a P NO P R O B L E M F o R t S C e N CALCULATE STEP I STEP Z PRIORITY 8 RAW S C O R E S FOR E A C H R E F t B E N r t P CoNirONCMT IN T A B L E S AT t N D OF PANEL B t p e t T WITH 12AI0 TOTALS E N T E R C P M A<T S V S T t r ^ s 3 Z CIRCLE HIGHEST AARP 1?AW SCORE IN EACH CTTHER SYSTEM CIRCUS NEXT HIGHEST SCORE IF WITHIN 4 POINTS OF TOP SCORE *⢠UOW ' STEP 3 N U M B E R OF S Y S T E M S CIRCLE FREQUENCY DISTRIBUTION FACTOR NUMQen. OP s y s r C M f H i a H I 2. 3 «R M«RE B £ L O W i N U M B E R O F S Y S T E M S LOV>< 0 1 0 1 Z. 1 4 / 3 1 1 1 ( f a ) 1 ¥ 2 R Msec 1 2. 1 4 1 4 ⢠⢠⢠AARP RA>W SCORCS ⢠I n o ⢠⢠TOTAL PRIORITY ®
TITLE FUSION WELDING LARGE DIAMETER DIMENSIONAL TOLERANCE -320- E FRAMES HOLDING CLOSE CHART NO PRIORITY RELATE ED CAI C MR CHARTS 70^ MANUFACTURING REQUIREMENT To J o i n w i t h f u s i o n b u t t welds t h e ends o f v e r y l a r g e one p i e c e Z s e c t i o n s o f 0 030 Inch t h i c k n e s s i n t o frames w i t h a diameter up t o 60 f e e t w i t h t o l e r a n c e o f + 0 08 inches M a t e r i a l s o f c o n s t r u c t i o n are alpha t i t a n i u m beta t i t a n i u m p r e c i p i t a t i o n s t r e n g t h e n e d n i c k e l base s u p e r a l l o y s and a u s t e n i t i c s t a i n l e s s s t e e l The Z s e c t i o n shape r e q u i r e s extreme movement o f w e l d i n g head Dimensional t o l e r a n c e s are d i f f i c u l t t o c o n t r o l f o r such l a r g e diameter s e c t i o n s which w i l l be used f o r r e c o v e r a b l e booster I n t e r s t a g e and I n t e r t a n k s t r u c t u r e s and t h r u s t bulkhead s t r u c t u r e s AARP REFERENCES E Chort. H L 186 B Char ts . 92 97a P«FVPS Char ts . APPLICABLE PROCESS one of the f o l l o w i n g depending on s p e c i f i c a p p l i c a t i o n ELECTRON BEAM LASER PLASMA ARC TIG and MIG FUSION WELDING Code 6 01 12 6 01 15 6 01 11 6 01 01 6 01-03 STATE OF THE ART ASSESSMENT Use o f f u s i o n w e l d i n g processes r e s u l t i n g i n minimum shrinkage and angular d i s t o r t i o n p l u s a l l p o s i t i o n w e l d i n g t o avoid m a n i p u l a t i n g such a l a r g e r i n g w i l l s i m p l i f y h o l d i n g the as welded d i m e n s i o n a l t o l e r a n c e s L o c a l chamber e l e c t r o n beam w e l d i n g i s s t a t e of the a r t The t h i c k n e s s o f s e c t i o n i s w i t h i n the r e a l m o f p o s s i b i l i t y f o r a p o w e r f u l ruby l a s e r These two processes w i l l r e s u l t i n the l e a s t p o s s i b l e d i s t o r t i o n Other c a n d i d a t e processes i n order of i n c r e a s i n g I n h e r e n t d i s t o r t i o n problems are plasma a r c MIG and TIG f u s i o n w e l d i n g T o o l i n g i s s t a t e o f the a r t Welded j o i n t s must e x h i b i t adequate toughness a t 423 F The weldable b e t a t i t a n i u m a l l o y p r e s e n t l y a v a i l a b l e (13V l l C r 3 Al) e x h i b i t s poor f r a c t u r e toughness as welded T h i s has been a t t r i b u t e d t o the presence of h i g h r e s i d u a l w e l d i n g s t r e s s e s The c l a s s i c a l post w e l d thermal t r e a t m e n t can cause weld embrlCClement b u t the reason f o r t h i s has n o t been i d e n t i f i e d A program should be i n i t i a t e d t o i d e n t i f y the reason f o r such e m b r I t t l e m e n t and CO develop a s u c c e s s f u l thermal t r e a t m e n t A l t e r n a t i v e l y a beta t i t a n i u m a l l o y should be developed i n which w e l d a b i l i t y i s designed i n t o the system S i g n i f i c a n t r e d u c t i o n i n r e s i d u a l s t r e s s and r e s u l t a n t Increase I n toughness has been a t t a i n e d by two methods The f i r s t i s c o l d r o l l i n g the weld t o a 15 t o 20 per c e n t r e d u c t i o n The second i s r e s i s t a n c e h e a t i n g and r o i l i n g u t i l i z i n g a standaru r e s i s t a n c e seam welder N e i t h e r t e c h n i q u e appears r e a d i l y a p p l i c a D l e t o the s i x t y f o o t diameter Z frames Several programs are underway d i r e c t e d towards the development o f Improved alpha t i t a n i u m a l l o y s f o r c r y o g e n i c a p p l i c a t i o n s I n a d d i t i o n type 304 s t a i n l e s s s t e e l and H a s t e l l o y B and type 718 n i c k e l base a l l o y s have been found s u f f i c i e n t l y tough f o r s t r u c t u r a l a p p l i c a t i o n s a t 423 F ALTERNATE PROCESSES RESISTANCE SPOT WELDING Code 6 02 00
321 TITLE ADHESnE BOND HIGH TEMPERATURE HONEYCOMB STRUCTURES CHART NO y ^ y PRIORITY RELATED CAMR CHARTS TAX MANUFACTURING REQUIREMENT Bonding o f s t a i n l e s s s t e e l s u p e r a l l o y t i t a n i u m or d i s p e r & i o n stren£thened f o i l s ( 1 ) Core t o cor e (2) Face sheet Co core Process must be economical and r e l i a b l e J o i n t s must w i t h s c a n up Co 2200F f o r up t o 80 hours c o r r o s i o n and o x i d a t i o n r e s i s t a n c e t o 30 000 hours and 175 db a c o u s t i c environment AARP REFERENCES E C h o f s 5 116_ B Chnrt. 3 50a P&FVPS Char ts . APPLICABLE PROCESS ADHESIVE BONDING Code 6 08 00 STATE OF THE ART ASSESSMENT Adhesive bonding processes have been developed f o r use t o 600 F f o r s e v e r a l hundred hours C u r r e n t work i s producing more s t a b l e adhesives but new monomeric forms must be developed f o r se t o ISOOt These may be i n o r g a n i c r a t h e r than o r g a n i c monomers but t h e r e are some i i i f l i c a c i o n s thac such m a t e r i a l s can be developed Poor p e e l and low shear s t r e n j , t h c h a r a c t e r i z e present adhesives and th e r e i s no i n d i c a t i o n t h a t these c h a r a c C e r i s t i c s can be improved as the usafee temperature i s increased Improvements i n t e n s i l e shear s.tr ngch o f i n o r g a n i c adhesives Co 15 000 p s i a t room temperature and 10 000 p s l at 1500 F were achieved as a r e s u l t o f work from 1956 t o 1962 Inadequate d u c t i l i t y and low peel s t r e n g t h caused work t o \e suspended D e t e r i o r a t i o n o f PBI and P I adhesives on t i t a n i u m at h i g h temperatures occurs more r a p i d l y than on s t a i n l e s s s t e e l or s u p e r a l l o y s T h i s i s a s p e c i a l problem w i t h t i t a n i u m t h a t r e q u i r e s s o l u t i o n However no m a n u f a c t u r i n g development program can be o u t l i n e d a t t h i s p o i n t Suggestions f o r m a t e r i a l s development are a t t a c h e d CRITICAL PROBLEMS The p r i n c i p a l problems a r i s e f r o m (1) Inadequate s t a b i l i t y o f adhesives (2) Low shear s t r e n g t h o f adhesives (3) Poor p e e l s t r e n g t h Peel s t r e n g t h i s i m p o r t a n t i n honeycomb because l o c a l h e a t i n g generates normal s t r e s s e s t h a t oppose b u c k l i n g o f the face sheets (4) Decomposition o f adhesive generates i n t e r n a l pressure l e a d i n g t o peel s t r e s s e s on the core t o face j o i n t s (5) Loss o f bond t o metal on prolonged h e a t i n g a t e l e v a t e d temperature (6) Panel f l a t n e s s ALTERNATE PROCESSES BRAZE OR DIFFUSION BOND Code 6 05 00 6 09 00
3 2 2 - CHART SUGGESTED MATERIALS DEVELOPMENT GOALS OBJECTIVE The o b j e c t i v e i s t o develop new monomerlc forms t h a t are e i t h e r o r g a n i c or i n o r g a n i c and are s u i t a b l e f o r p o l y m e r i z a t i o n i n t o adhesives which are s t a b l e up t o 2200 F Because t h i s g o a l i s so f a r beyond t h e p r e s e n t s t a t e o f the a r t secondary g o a l s are recommended t o i n c l u d e 1200 F ( f o r s t a i n l e s s s t e e l ) 1800 F ( f o r s u p e r a l l o y s ) and 2200 F ( f o r d i s p e r s i o n s t r e n g t h e n e d a l l o y s ) BACKGROUND The use of honeycomb sandwich panels i s s t r o n g l y dependent on c o s t and r e l i a b i l i t y Adhesive bonded honeycomb i s w i d e l y used because c o s t i s much lower than f o r brazed honeycomb G e n e r a l l y p r o c e s s i n g ( c u r i n g ) can be performed a t temperatures lower t h a n those p e r m i s s i b l e as use temperatures whereas b r a z i n g o p e r a t i o n s are c h a r a c t e r I s t l c a l l y p erformed above t h e f i n a l use temperature E x t e n s i o n o f the advantages o f adhesive bonding t o h i g h e r temperature s t r u c t u r e s w i l l be o f enormous b e n e f i t However t h i s w i l l n o t be achieved by s t a t e o f the a r t advancement by 1970 and s p e c i a l e f f o r t w i l l be r e q u i r e d t o reach t h e g o a l s e t o r even an a p p r e c i a b l e f r a c t i o n o f t h e g o a l APPROACH I t IS not recommended t h a t a s i n g l e program be i n i t i a t e d Success i n a program r a n g i n g from new monomerlc form development t o honeycomb sandwich p a n e l s f o r s t r u c t u r a l t e s t s i s not l i k e l y t o f i n d the r e q u i r e d range o f t a l e n t s Rather programs t o develop new adhesives should c o n s t i t u t e the f i r s t step A p p l i c a t i o n programs t o develop p r o c e s s i n g w i t h u l t i m a t e d e m o n s t r a t i o n t o hardware should c o n s t i t u t e the second s t e p Because o f the many unknowns i n such an approach i n c l u d i n g c o n t r i b u t i o n s from b a s i c r e s e a r c h when programs might be I n i t i a t e d no s p e c i f i c o u t l i n e w i l l be proposed I f t i t a n i u m i s a c a n d i d a t e m a t e r i a l f o r t h i s a p p l i c a t i o n a c r i t i c a l problem becomes d e t e r i o r a t i o n o f J o i n t q u a l i t y w i t h time T h i s problem should be t a c k l e d by c o u p l i n g basic and a p p l i e d r e s e a r c h Surface p r e p a r a t i o n o f metals f o r adhesive bonding g e n e r a l l y i n v o l v e s g e n e r a t i o n o f an i n o r g a n i c compound l a y e r t o p r o v i d e a t r a n s i t i o n between the metal l a t t i c e and o r g a n i c adhesive Treatments w i t h o x i d i z i n g a c i d s phosphates e t c may be c i t e d I t appears t h a t r e t e n t i o n o f these t r a n s i t i o n l a y e r s i s e s s e n t i a l t o t h e p r e s e r v a t i o n o f bond s t r e n g t h Mechanism by which these l a y e r s are d i s s i p a t e d a t h i g h temperatures must be understood I f t h e g o a l o f 30 000 hours I s t o b ^ approached Other d e t e r i o r a t i o n mechanisms i n adhesive bonded j o i n t s (e g oxygen r e a c t i o n ) are b e t t e r understood w i t h approaches t o combat these problems by u s i n g a d d i t i v e s However a g e n e r a l study o f d e t e r i o r a t i o n o f adhesive bonded J o i n t s w i t h time e s p e c i a l l y w i t h r e f e r e n c e t o t i t a n i u m should be consid e r e d as p a r t o f advancing the s t a t e o f the a r t I t i s concluded t h a t the s e v e r a l avenues t o be e x p l o r e d and the d i f f e r e n t approaches r e q u i r e d by d i f f e r e n t a l l o y s w i l l develop i n t o a number o f c o n c u r r e n t programs I n summary program approaches are recommended i n (1) Development o f new monomer form f o r adhesives ( l o n g range basic r e s e a r c h g o a l ) (2) Development o f d e t e r i o r a t i o n r e s i s t a n t adhesive ( b a s i c r e s e a r c h g o a l ) b y (a) study o f mechanism o f d e t e r i o r a t i o n (b) study o f s p e c i a l problems w i t h t i t a n i u m ( c ) develupment o f d e t e r i o r a t i o n r e s i s t a n t J o i n t s (3) Development o f more s t a b l e h i g h temperature adhesives f o r h i g h temperature use based on new monomers and/or on d e t e r i o r a t i o n r e s i s t a n t approaches (4) Demonstration program o f s t a b l e h i g h temperature adhesives on honeycomb sandwich w i t h f u l l t e s t program i n c l u d i n g long time exposure t e s t s ( a t l e a s t 1000 hours) Separate programs may be r e q u i r e d f o r each p l a t e a u o f temperature and d i f f e r e n t m a t e r i a l s
323 TITLE CHEMICAL BONDING OF ABLATOR TO METAL SUBSTRUCTURE CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Chemical bonding o f an org a n i c or cermet a b l a t o r t o sma l l r a d i u s l e a d i n g edge m e t a l l i c s u b s t r u c t u r e Bond shear s t r e n g t h o f 5000 p s i d e s i r e d A b l a t o r c h a r a c t e r i s t i c s would be a heat of a b l a t i o n o f 15 000 B t u / l b under l o c a l p r e s s u r e o f 500 t o 1000 p s i and i n t h e form o f a h e m i c y l l n d e r about 30 Inches long The approximate t h i c k n e s s f o r an org a n i c a b l a t o r would be 1 0 in c h ( e s t i m a t e d ) and f o r the cermet about 0 25 Inch AARP REFERENCES E Charts 137 B C h a t s . 62a P4FVPS Char ts . APPLICABLE PROCESS CHEMICAL BONDING Code 6 08 00 STATE OF THE ART ASSESSMENT N e i t h e r o r g a n i c nor cermet a b l a t o r m a t e r i a l s have been developed Heat o f a b l a t i o n r e q u i r e d i s 50 percent above what I s now a v a i l a b l e Such a v a l u e does not appear t o be p o s s i b l e w i t h the m a t e r i a l s o f h i g h atomic weight suggested i n AARP r e f e r e n c e s I f 100 percent gas g e n e r a t i o n I s achieved a t an e n t h a l p y o f 10 000 B t u / l b average m o l e c u l a r w e i g h t o f gases formed must be below about 20 This l i m i t s m a t e r i a l s t h a t may be used Development o f techniques f o r attachment o f a b l a t o r t o m e t a l l i c s u b s t r u c t u r e should be cons i d e r e d as a c o n c u r r e n t o b j e c t i v e d u r i n g the development o f the a b l a t o r m a t e r i a l A l t h o u g h development o f the s p e c i f i c m a t e r i a l s p e c i f i e d i n the AARP c h a r t s may not be p o s s i b l e s o l u t i o n s t o t h i s a b l a t i o n problem have been found w i t h o t h e r m a t e r i a l s These s o l u t i o n s appear s a t i s f a c t o r y and t h e r e f o r e no program i s recommended C R I T I C A L P R O B L E M S NONE ALTERNATE PROCESSES POSSIBLY BRAZING DEPENDING ON CHARACTERISTICS OF ABLATOR AND SUBSTRUCTURE Code
324 TITLE ADHESIVE BOND PLASTIC (REINFORCED) TO SUBSTRUCTURE CHART PRIORITY RELATED CAMR CHARTS 76X MANUFACTURING REQUIREMENT Adhesive bond heat s h i e l d or e l e c t r o m a g n e t i c t r a n s p a r e n c y t o p r i m a r y s t r u c t u r e s J o i n t must a t t a i n shear s t r e n g t h o f 5000 p s l a t a temperature o f 600 F f o r 30 minutes Heat s h i e l d s w i l l have s u r f a c e areas t o 100 f t ^ AARP REFERENCES E rhnr t . 281 B Chert, 133a 135a b V ' PAFVPS Chart. APPLICABLE PROCESS Code BONDING BY ADVANCED ORGANIC ADHESIVES 6 08 02 STATE O F THE ART ASSESSMENT C u r r e n t adhesives (e g PBI) w i l l meet the 600 F r equirement but n o t 5000 p s i i n t e n s i l e shear P r e s e n t adhesives are l i m i t e d t o 3000 p s l and w i l l r e t a i n t h i s s t r e n g t h f o r many hours a t 600 F The c u r i n g temperature o f PBI adhesives i s t y p i c a l l y 600 F under 200 p s l p r e s s u r e so Chat o n l y h i g h d e c o m p o s i t i o n temperature a b l a t o r s can be J oined The p o l y l m i d e adhesives can be cured a t 500 F t o g i v e a somewhat lower s t r e n g t h a t 600 F ( t y p i c a l l y 2500 t o 3000 p s i ) The t e n s i l e s t r e n g t h o f adhesives I s much h i g h e r than the t e n s i l e - s h e a r s t r e n g t h so t h a t c a r e f u l d e s i g n t o maximize p e e l i n the J o i n t may p e r m i t o b t a i n i n g t h e d e s i r e d v a l u e o f 5000 p s l s t r e n g t h Recent work on c u r i n g r e s i n s a t room temperature by h i g h energy ( e l e c t r o n ) r a d i a t i o n may o f f e r h i g h e r s t r e n g t h by a l l o w i n g m o d i f i c a t i o n o f f o r m u l a t i o n s used f o r adhesives No m a n u f a c t u r i n g development program i s proposed a t the p r e s e n t time because (1) Inadequate p r o p e r t i e s o f adhesives I s a problem and '2) n e i t h e r a b l a t o r nor t r a n s p a r e n c y can be d e f i n e d a t the p r e s e n t time P o i n t s which should r e c e i v e s p e c i a l a t t e n t i o n a t such time as a new adhesive system becomes a v a i l a b l e f o r f a b r i c a t i o n t r i a l s I n c l u d e U i r f e r e n c l a l thermal expansion between a b l a t o r (or t r a n s p a r e n c y ) and s u b s t r u c t u r e Mechanical f a s t e n e r s w i l l i n crease s t r e n g t h o f J o i n t i n shear and p e e l but r a i s e temperature o f g l u e l i n e by thermal conductance P r o c e s s i n g c y c l e of adhesive must not damage a b l a t o r or t r a n s p a r e n c y and s u b s t r u c t u r e Reduction o f c u r i n g temperature reduces s t r e n g t h o f adhesive Adhesive must w i t h s t a n d space and r e e n t r y c o n d i t i o n s (vacuum and c o l d ) r a d i a t i o n D e t e r i o r a t i o n of J o i n t s t r e n g t h w i t h time e s p e c i a l l y on t i t a n i u m ALTERNATE PROCESSES MECHANICAL FASTENING COMBINED WITH ADHESIVE BONDING Code 6 08 00/6 11 00
325 TITLE HARDFACING OF STEEL PADS FOR LUNAR VEHICLES CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Attachment o f hard rough a b r a s i v e r e s i s t a n t m a t e r i a l t o s t e e l h a l f b a l l s used as c o n t a c t s u r f a c e s f o r wheels on a lu n a r t r a v e r s e r AARP REFERENCES E Cha »s B C h a r t s . 169a P&FVPS Char ts . APPLICABLE PROCESS HARDFACING BY WELDING OR BRAZING OF INSERTS Code 6 01 00 6 05 00 STATE OF THE ART ASSESSMENT Hard f a c i n g by Welding Techniques used f o r d r i l l i n g b i t s are h i g h l y advanced and pr o v i d e s u r f a c e s t h a t operate under h i g h pressures over a wide range o f temperatures (above 225 F of lunar s u r f a c e ) The use of s t e e l tube e l e c t r o d e s f i l l e d w i t h crushed c a s t c a r b i d e and a l l o y i n g elements p r o v i d e a sur f a c e w i t h v a r i a b l e roughness depending on the p a r t i c l e s i z e o f the cast c a r b i d e I t i s b e l i e v e d t h a t the pads can be made w i t h i n the present s t a t e o f the a r t Brazed I n s e r t s I n s e r t s o f cemented c a r b i d e s o f hot pressed c a r b i d e m a t r i c e s c o n t a i n i n g diamonds and oth e r hard f a c i n g s are used i n a v a r i e t y o f c u t t i n g d r i l l i n g and wear r e s i s t a n t a p p l i c a t i o n s These i n s e r t s are brazed i n pla c e Design i s u s u a l l y arranged so t h a t the braze i s i n com pr e s s i o n I t i s b e l i e v e d t h a t the i n s e r t approach can be a p p l i e d s u c c e s s f u l l y t o these wheel s u r f a c e s w i t h i n the present s t a t e of the a r t No ma n u f a c t u r i n g development program i s r e q u i r e d CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Code
326 TITUE JOINT PYROLYTIC GRAPHITE CLOTH TO CONCRETE BASE CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Bond p y r o l y t l c g r a p h i t e c l o t h t o con c r e t e by c o l d c u r i n g adhesive Refurbishment must be p o s s i b l e Adhesive should p r o v i d e s t r o n g bond t o c o n c r e t e and p y r o l y t l c g r a p h i t e Adhesive should n o t decompose suddenly t o generate l a r g e amount o f gas when heat from flame reaches bond l i n e Exposed edges o f bond l i n e should n o t d i s r u p t t o cause e r o s i o n o f c l o t h A p p l i c a t i o n I s t o launch pad flame d e f l e c t o r s i n t h i c k n e s s e s t o 3 i n c h maximum and we i g h t s from 3 000 t o 5 000 l b s temperature t o 8000 F AARP REFERENCES E Chart» B Char ts . 160b P«FVPS C h a r t s . APPLICABLE PROCESS ADHESIVE BOND Code 6 08 00 STATE-OF THE ART ASSESSMENT Cold s e t t i n g adhesives t o make these J o i n t s are w i t h i n the pre s e n t s t a t e o f the a r t (e g epoxy or s i l i c o n e type w i t h maximum c o n t e n t o f i n e r t f i l l e r ) E f f e c t o f s p i l l a g e of c r y o g e n i c and a c t i v e f u e l s and o x i d i z e r s i s n o t c o m p l e t e l y known i n a l l cases Excessive s p i l l a g e o f m a t e r i a l s such as IRFNA ( i n e r t red fuming n i t r i c a c i d ) may r e q u i r e r e f u r b i s h m e n t o f pad as a r e s u l t o f damage t o con c r e t e so t h a t problems o t h e r than t h a t o f adhesive must be c o n s i d e r e d CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Code
327 TITLE ADHESIVE BOND FLEXIBLE TUBES TO BELLOWS CHART NO PRIORITY RBIATBD CAMR CHARTSi MANUFACTURING REQUIREMENT E l a s t o m e r i c tube r e q u i r e d as a gas i n f l a t a b l e c o l l a r t o s e a l two h a l f s h e l l s a g a i n s t l i q u i d hydrogen f u e l e d launch v e h i c l e tankage t o p r o v i d e thermal i n s u l a t i o n p r i o r t o launch H a l f s h e l l s ere r e t r a c t e d b e f o r e launch J o i n t s must be vacuum t i g h t and f l e x i b l e a t temperatures down t o 425 F over long p e r i o d s o f time Tube must w i t h s t a n d s h o r t time exposure t o 800 F from booster exhaust gas h e a t i n g AARP REFERENCES P4FVPS Charts - _ _ â APPLICABLE PROCESS Code ADHESIVE BOND 6 08 00 STATE OF THE ART ASSESSMENT The compounding of an e l a s t o m e r i c m a t e r i a l f l e x i b l e a t 425 F i s the c o n t r o l l i n g f a c t o r I n t h i s problem C u r r e n t s t a t e o f the a r t i s t h a t no m a t e r i a l i s a v a i l a b l e t h a t w i l l meet these requirements Before i n i t i a t i n g f a b r i c a t i o n t r i a l s f o r p r o t o t y p e hardware the f o l l o w i n g e f f o r t i s r e q u i r e d 1 Development of m a t e r i a l t h a t w i l l meet requirements o f f l e x i b i l i t y a t 425 F 2 Design o f J o i n t s w i t h coated mylar or ot h e r m u l t l l a y e r p o l y m e r i c sheet t h a t w i l l be gas t i g h t 3 Development o f adheslves t h a t w i l l have adequate f l e x i b i l i t y a t 425 F C R I T I C A L P R O B L E M S M a t e r i a l development ALTERNATE PROCESSES HEAT SEAL Code 6 08 05
328- TITLE ADHESIVE BONDING OF ELASTOMERIC BOOT TO METAL CHART PRIORITY R I U T B D CAMR CHARTSi MANUFACTURING REQUIREMENT An e l a s t o m e r l c boot must be Joined t o a h i g h s t r e n g t h m e t a l l i c f o o t f o r use over the range 240 F t o 225 F Boot must be a b r a s i o n r e s i s t a n t but be r e p l a c e a b l e a f t e r wear Boot i s used as a c o v e r i n g i n c o n t a c t w i t h l u n a r s u r f a c e o f wheels f o r a l u n a r e x p l o r a t o r y t r a v e r s e r AARP REFERENCES E Chorft B Charts 169b P4FVPS C h a r t s . APPLICABLE PROCESS ADHESIVE BOND Code 6 08 00 STATE OF THE ART ASSESSMENT M a t e r i a l s such as m o d i f i e d urethane rubbers w i l l be c a n d i d a t e s f o r t h i s a p p l i c a t i o n and can be Joined t o metals by adhesives d e r i v e d from the same basic polymers Glass t r a n s i t i o n temperatures o f pr e s e n t elastomers may r e s t r i c t use range Adhesive i s l e s s o f a problem than b a s i c elastomer f o r boot D e t e r i o r a t i o n o f elastomer (and ad h e s i v e ) under s o l a r and o t h e r r a d i a t i o n s must be e v a l u a t e d CRITICAL PROBLEMS M a t e r i a l development r e q u i r e d f o r elastomer f o r use from 2A0 F t o 225 F ALTERNATE PROCESSES NONE Code
329 TITLE ADHESIVE BONDING OF SILICONE RUBBER TO TITANIUM FOR EXTRA VEHICULAR ADVANCED SPACE SUIT CHART NO PRIORITY RELATED CAMR^ CHARTS MANUFACTURING REQUIREMENT J o i n r i n g s o f s i l i c o n e rubber t o t i t a n i u m r i n g s t o p r o v i d e r e s t r i c t i o n a t J o i n t s on gas f l o w from main body o f advanced e x t r a v e h i c u l a r a s t r o n a u t space s u i t Dimensional c o n t r o l e s s e n t i a l t o c o n t r o l p r e s s u r e drop AARP REFERENCES c /-I B Charts 172b ^ P4FVPS Charts ^ â APPLICABLE PROCESS Code ADHESIVE BOND 6 08 00 STATE OF THE ART ASSESSMENT S i l i c o n e rubber adhesives w i l l bond t o c l e a n s u r f a c e s even w i t h o u t a i d o f pr i m e r s One problem w i t h some c u r r e n t adhesives i s t h a t c u r i n g a t room temperature i s slow and h i g h e r temperatures are i n h i b i t e d by i n s i t u attachment t o space s u i t C o n t r o l o f c u r i n g time i s a problem t h a t i s understood and can be v a r i e d by the manufacturer S t r e n g t h s may r e a d i l y exceed cohesive s t r e n g t h o f s i l i c o n e rubber There do not appear t o be any c r i t i c a l problems t h a t w i l l not be r e s o l v e d by pres e n t s t a t e o f the a r t i n the course o f development o f the space s u i t No m a n u f a c t u r i n g development program i s r e q u i r e d CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Code
330 TITLE RESISTANCE WELDING COATED MATERIALS CHART PRIORITY RELATED CAMR CHARTS: MANUFACTURING REQUIREMENT Resistance spot w e l d i n g i s r e q u i r e d f o r assemblies which are t o operate i n o x i d i z i n g t u r e s t o 1800 2000 F a t an a c c o u s t i c l e v e l o f on mechanical s t r e s s e s d u r i n g a 30 000 hour se s u p e r a l l o y s would be g i v e n an o x i d a t i o n p r o t e c the w e l d i n g o p e r a t i o n I t i s d e s i r a b l e t o per Impairment t o the p r o t e c t i o n a f f o r d e d by the c Under l e s s severe environment would be s i m i l a r s t a i n l e s s s t e e l s which might r e c e i v e c o a t i n g p r o t e c t i o n J o i n i n g o f sheet and e x t r u s i o n d e t a i l s o f e r o s i v e and c o r r o s i v e environments a t tempera 165 185 db Thermal c y c l i n g s t r e s s e s are imposed r v i c e l i f e D e t a i l s o f p r e c i p i t a t i o n s t r e n g t h e n e d t i v e c o a t i n g b e f o r e assembly and recoated a f t e r form the r e s i s t a n c e w e l d i n g o p e r a t i o n w i t h o u t o a t i n g so t h a t r e c o a t l n g can be e l i m i n a t e d a p p l i c a t i o n s f o r t i t a n i u m a l l o y s and a u s t e n l t i c t r e a t m e n t s f o r o x i d a t i o n e r o s i o n c o r r o s i o n AARP REFERENCES E Charts 21, 2 7 _ B Chnrt« 11. 15a. 16a P4FVPS Char ts . APPLICABLE PROCESS RESISTANCE SPOT WELDING Code 6 02 01 STATE OF THE ART ASSESSMENT The known c o a t i n g s f o r p r o t e c t i n g p r e c i p i t a t i o n strengthened s u p e r a l l o y s i n an o x i d i z i n g atmosphere a t 1800 F a t an a c o u s t i c l e v e l o f 165 185 db and f o r p r o t e c t i n g p r e c i p i t a t i o n s t r e n g t h e n e d s u p e r a l l o y s a u s t e n i t i c s t a i n l e s s s t e e l and beta t i t a n i u m a l l o y s i n an e r o s i v e environment f o r 30 000 hours a t an a c o u s t i c l e v e l o f 165 185 db, are d e s t r o y e d by the r e s i s t a n c e spot w e l d i n g o p e r a t i o n There are no m o d i f i c a t i o n s of spot w e l d i n g technique or equipment which would a v o i d t h i s damage Repair o f the c o a t i n g i n the r e s i s t a n c e weld area does not appear p r a c t i c a l a t t h i s time P r o t e c t i v e c o a t i n g s must be a p p l i e d t o assemblies a f t e r w e l d i n g i s completed M a t e r i a l s development t o p r o v i d e p r o t e c t i v e c o a t i n g s which would w i t h s t a n d w e l d i n g i s advocated CRITICAL PROBLEMS ALTERNATE PROCESSES MECHANICAL FASTENING Code 6 11 00
331 TITLE FUSION WELDING DISPERSION STRENGTHENED SUPERALLOYS CHART NO PRIORITY RELATED CAMR^CHARTS MANUFACTURING REQUIREMENT J o i n d e t a i l p a r t s o f d l s p e i s l o n strengthened s u p e r a l l o y s t o produce s t r u c t u r e s f o r e l e v a t e d temperature s e r v i c e S t r u c t u r e s I n c l u d e major s t r u c t u r a l f i t t i n g s r e q u i r i n g c l o s e d i m e n s i o n a l t o l e r a n c e i n weldment up t o 5 f e e t long edge members f o r curved or f l a t s t i f f e n e d panels up t o 9 f e e t x 20 f e e t c o r r u g a t e d web welded t o caps up t o A8 inches long sur aces o f r e v o l u t i o n up t o 6 f e e t diameter x 15 f e e t long x 0 125 inches t h i c k and m a i n t a i n i n g diameter o f + 0 1 pe r c e n t a i r f o i l s (guide and d l f f u s e r vanes) t o 1 f o o t wide x 2 f e e t long x 0 125 i n c h t h i c k m a i n t a i n i n g squareness o f end f l a n g e s t o w i t h i n + 1 p e r c e n t Thicknesses t o be j o i n e d I n c l u d e sheet from 0 010 i n c h t o 0 120 i n c h 0 25 i n c h e x t r u s i o n s t o 0 080 i n c h f o r g i n g s and machined bar s t o c k p l a t e from 0 12 i n c h AARP REFERENCES E Charts 27 58 59 89 90 116 271 272 287 15a B C h a r t s . P4FVPS Charts J o i n i n g No 12_ 18c 30b c 31c 41c 42b c 50b 51b 52a 122b c 133d e 134b APPLICABLE PROCESS One o f the f o l l o w i n g depending on end Item ELECTRON BEAM PLASMA ARC TIG and MIG FUSION WELDING Code 6 01 12 6 01 11 6 01 01 6 01 03 STATE OF THE ART ASSESSMENT D i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s p r o v i d i n g d e s i r e d w e l d a b i l l t y have not y e t been developed The c u r r e n t l y a v a i l a b l e d i s p e r s i o n s t r e n g t h e n e d system i s TD n i c k e l Optimum p r o p e r t i e s are developed i n t h i s m a t e r i a l by means o f c a r e f u l l y s e l e c t e d mechanical w o r k i n g and an n e a l i n g c y c l e s The r e s u l t i n g f i b r o u s s t r u c t u r e c o n t r i b u t e s h e a v i l y t o i t s mechanical p r o p e r t i e s and as a r e s u l t i t i s s t r o n g l y a n i s o t r o p i c J o i n i n g TD n i c k e l by f u s i o n w e l d i n g ( t h a t i s by m e l t i n g and subsequent coalescence) d e s t r o y s the elongated g r a i n s t r u c t u r e and agglomerates d i s p e r s e d t h o r l a s e r i o u s l y r e d u c i n g base metal s t r e n g t h F u s i o n welded 0 006 i n c h t h i c k TD n i c k e l f o i l e x h i b i t e d the f o l l o w i n g t e n s i l e s t r e n g t h s when t e s t e d a t 2000 F TIG welded about 5000 p s i e l e c t r o n beam welded about 11 000 p s l base m e t a l s t r e n g t h a t the same temperature was a p p r o x i m a t e l y 17 000 p s i The e l e c t r o n beam welds a t room temperature were i n the order o f 82 000 p s i as compared w i t h 45 000 p s l f o r TIG welds These data appear t o I n d i c a t e t h a t the most d e s i r a b l e f u s i o n w e l d i n g process f o r TD n i c k e l i s one t h a t w i l l produce a weld w i t h the lowest p o s s i b l e energy i n p u t r e s u l t i n g i n the s m a l l e s t p r a c t i c a l volume of melted m a t e r i a l i n the J o i n t and a heat a f f e c t e d zone o f minimum dimensions The f u s i o n w e l d i n g energy sources can be r a t e d i n order o f m e r i t as a p p l i e d t o j o i n i n g TD n i c k e l 1 E l e c t r o n Beam Minimum energy i n p u t l i m i t s w e l l w i t h i n c a p a b i l i t y o f process The l a r g e s t assemblies of concern 9 f e e t x 20 f e e t panels and r a m j e t d l f f u s e r components 6 f e e t diameter x 15 f e e t long are w i t h i n economic vacuum chamber s i z e l i m i t a t i o n s Furthermore the demonstrated c a p a b i l i t y t o e l e c t r o n beam weld a t i n t e r m e d i a t e pressures o f 10 t o 100 microns t o g e t h e r w i t h the A i r Force funded program t o develop a p o r t a b l e moving s e a l e l e c t r o n beam w e l d i n g system may c o m p l e t e l y e l i m i n a t e s i z e as an economic c o n s i d e r a t i o n 2 Laser At p r e s e n t average power c a p a b i l i t y l i m i t s the l a s e r t o gauges up t o 0 010 Inch maximum I t i s t h e o r e t i c a l l y capable o f even h i g h e r power d e n s i t y and consequently lower energy Continued on next page ALTERNATE PROCESSES FLASH BUTT WELDING FRICTION WELDING DIFFUSION BONDING BRAZING Code 6 02 09 6 03 00 6 09 00 6 05 00
CHAR -332- STATE-OF THB ART ASSESSMENT, continued Input than electron beam welding However R & D Is required to bring the average power le v e l Bu££lclontly high f o r the material thlcIuioaBeB of Intereat 3 P,l,aB.mp..Arc. Froceos equipment and welding techniques need development and refinement When t h i s la aceonpllBhad the procaas w i l l lag bahlnd electron bean and/or laaar In marlt (as pre- viously defined) but may be economically a t t r a c t i v e for less c r i t i c a l applications A E l e c t r i c Arc MIG Of the two e l e c t i l c arc processes o f i n t e r e s t MIG w i l l r e s u l t i n the lower t o t a l energy i n p u t per u n i t l e n g t h o f j o i n t I t i s however l e s s amenable t o p r e c i s e c o n t r o l as compared w i t h TIG TIG P r e c i s e automatic equipment p r o v i d i n g a c c u r a t e c o n t r o l o f w e l d i n g parameters i s a v a i l a b l e Automatic TIG welds are g e n e r a l l y of h i g h q u a l i t y However the i n h e r e n t h i g h e r energy i n p u t i s d e t r i m e n t a l i n the case o f TO n i c k e l The j o i n t e f f i c i e n c y t h a t w i l l be a t t a i n a b l e i n f u s i o n welded d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s w i l l depend l a r g e l y upon the n a t u r e o f the a l l o y s t h a t are developed I f l i k e TD n i c k e l t h e y e x h i b i t a h i g h l y e l o n g a t e d g r a i n s t r u c t u r e w h i c h t r a n s m i t s a p r o p e r l y o r i e n t e d l o a d by shear from one g r a i n t o the n e x t then the s i t u a t i o n w i l l be q u i t e s i m i l a r t o t h a t encoun t e r e d w i t h TD n i c k e l I n such a case e l e c t r o n beam w e l d i n g p r o b a b l y w i l l be the most s u c c e s s f u l f u s i o n w e l d i n g process a t t a i n i n g J o i n t e f f i c i e n c i e s i n the o r d e r o f 50 p e r c e n t a t h i g h tempera t u r e I f a l l o y s are developed which are s t r e n g t h e n e d by some mechanism o t h e r than mechanical w o r k i n g such as age hardening then h i g h e r j o i n t e f f i c i e n c i e s w i l l p o s s i b l y be a t t a i n e d T h i s s i t u a t i o n i s analogous t o t h a t of f u s i o n w e l d i n g the p r e c i p i t a t i o n s t r e n g t h e n e d aluminum a l l o y s Component p a r t s f a b r i c a t e d f r o m these a l l o y s are Joined t o produce aerospace s t r u c t u r e s even though f u s i o n w e l d i n g degrades the p r o p e r t i e s o f the base met a l The d e t a i l s are designed w i t h l a n d s o f i n c r e a s e d t h i c k n e s s i n t h e j o i n t area w h i c h p r o v i d e l o c a l l y i n c r e a s e d c r o s s s e c t i o n t o compensate f o r l o s s of s t r e n g t h due t o the heat o f w e l d i n g S i m i l a r l y l o c a l r e i n f o r c e m e n t s t r i p s c o u l d be d i f f u s i o n bonded t o the d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y d e t a i l p a r t s t o r e i n f o r c e the j o i n t area t h i c k n e s s When e l e c t r o n beam w e l d i n g i s used the r e i n f o r c e - ment s t r i p s c o u l d a l t e r n a t i v e l y be brazed t o the d e t a i l s I t i s p o s s i b l e t o imagine a number o f schemes which may p o s s i b l y Improve J o i n t e f f i c i e n c y i n these a l l o y s T h e i r p o t e n t i a l e f f i c a c y however w i l l depend upon the p r o p e r t i e s o f the d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s t h a t are f i n a l l y developed For example i n c r e a s i n g the s o l i d i f i c a t i o n r a t e o f the weld m e t a l should reduce a g g l o m e r a t i o n The s o l i d i f i c a t i o n r a t e i s a l r e a d y v e r y h i g h and t h e r e f o r e so I s t h e t h e r m a l g r a d i e n t across the heat a f f e c t e d zone i n an e l e c t r o n beam weld a t h i g h speed The s o l i d i f i c a t i o n r a t e c o u l d be i n c r e a s e d f u r t h e r by p u l s i n g the e l e c t r o n beam a t a s u i t a b l e r e p e t i t i o n r a t e T h i s would i n c r e a s e the p o s s i b i l i t i e s o f p o r o s i t y and o f c r a c k i n g depending upon th e p r o p e r t i e s a t the base a l l o y A t the o t h e r extreme one c o u l d c o n s i d e r a h i g h energy process c a r r y i n g a l a r g e l i q u i d puddle and the u t i l i z a t i o n o f u l t r a s o n i c puddle s t i r r i n g t o I n s u r e d i s p e r s i o n of the s t r e n g t h e n i n g p a r t i c l e s The base metal now must t o l e r a t e h i g h energy i n p u t and l a r g e s h r i n k a g e s t r a i n s which i s r a t h e r u n l i k e l y A t h i r d scheme would r e q u i r e the development of a f i l l e r w i r e c o n t a i n i n g the s t r e n g t h e n i n g p a r t i c l e s i n a s u i t a b l y a d j u s t e d q u a n t i t y T h i s f i l l e r w i r e would be d e p o s i t e d by a low energy process t o m i n i m i z e m e l t i n g o f the base m a t e r i a l and time a t l i q u i d u s f o r example e l e c t r o n beam pu l s e d MIG pulsed TIG However i t i s more l i k e l y t h a t t h e s t r u c t u r e s w i l l be designed t o accept some l o s s o f s p e c i f i c s t r e n g t h a t the j o i n t s and t h a t e l e c t r o n beam w e l d i n g w i l l be w i d e l y u t i l i z e d f o r t h i s type o f a l l o y T h i s process o f f e r s the a d d i t i o n a l advantage t h a t the i n t e r i o r o f honeycomb or c o r r u g a t i o n core sandwich s t r u c t u r e s may be evacuated and sealed c o n c u r r e n t w i t h w e l d i n g the edge members T h i s may s i m p l i f y the p r o t e c t i v e c o a t i n g problem CONCLUSIONS AND RECOMMENDATIONS M a t e r i a l No m a n u f a c t u r i n g development a c t i o n I s recommended f o r f u s i o n w e l d i n g of p r e s e n t a l l o y s However a major e f f o r t should be made t o develop a l l o y systems t h a t are amenable t o Contlhned^ on n e x t page
-333- C o n c l u s l o n s and Recommendations, c o n t i n u e d CHART J o i n i n g by m e l t i n g and coalescence F u s i o n Welding When d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s a r e a v a i l a b l e and t h e i r p h y s i c a l and m e t a l l u r g i c a l c h a r a c t e r i s t i c s are determined the most s u i t a b l e f u s i o n w e l d i n g methods can be s e l e c t e d t h e w e l d i n g parameters o p t i m i z e d and c o m p a t i b l e d e s i g n e v o l v e d C o a t i n g The weldments must s u r v i v e s e r v i c e temperatures r a n g i n g f r o m 1800 t o 2200 F maximum o x i d a t i o n and c o r r o s i v e environments and severe a c o u s t i c environments t o 183 l b P r o t e c t i v e c o a t i n g s w i l l t h e r e f o r e be r e q u i r e d I t I s not f e a s i b l e t h a t f u s i o n w e l d i n g c o u l d be accom p l l s h e d t h r o u g h p r o t e c t i v e c o a t i n g s T h e r e f o r e the c o a t i n g s w i l l have t o be a p p l i e d t o the completed weldment Non d e s t r u c t i v e T e s t i n g Assuming t h a t an a l l o y system and f u s i o n w e l d i n g process are developed t o meet the AARF g o a l s t h e n o n - d e s t r u c t i v e t e s t i n g methods may be r e q u i r e d t o det e r m i n e the degree o f a g g l o m e r a t i o n I n a d d i t i o n t o presence o f weld d e f e c t s Eddy c u r r e n t t e c h n i q u e s s h o u l d be c o n s i d e r e d
334 TITLE FUSION WELDING REFRACTORY ALLOYS CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT F u s i o n w e l d i n g I s r e q u i r e d f o r J o i n i n g o f r e f r a c t o r y a l l o y s t o themselves and I n some a l l o y c ombinations over a wide range o f t h i c k n e s s e s I n complex c o n f i g u r e d p a r t s f o r use a t temperatures and times c h a r a c t e r i s t i c o f the s p e c i f i c v e h i c l e but g e n e r a l l y I n excess o f 2500 F so t h a t weldments must accept o x i d a t i o n p r o t e c t i v e c o a t i n g s w i t h o u t l o c a l l y a l t e r i n g the c o a t i n g e f f i c i e n c y I n use Sheet and p l a t e p r o d u c t s range from 0 010 Inc h t o 0 250 Inch t h i c k n e s s e s and c o u l d be welded I n combinations w i t h complex shape f o r g l n g s and c a s t i n g s and w i t h 0 007 Inch w a l l t u b i n g Fusion w e l d i n g as a r e p a i r procedure f o r p r o d u c t s such as c a s t i n g s I s r e q u i r e d Mechanical p r o p e r t i e s must e s s e n t i a l l y be e q u i v a l e n t t o those o f base metal and f r e e from c r a c k i n g I n complex r e s t r a i n e d weld c o n d i t i o n s T y p i c a l components are t h r u s t d e f l e c t i o n vanes a i r I n l e t s and d u c t i n g nose cones heat s h i e l d s heat exchangers r a d i a t o r s n o z z l e s combustion chambers AARP REFERENCES E Charts i i j . A5. 57, 88. 90. 117, 227. B C h a r t s . 4 28c,d 29b,c.d 30a.c Mb, l i O a . b . l26a.c. l h a . 31a.c 264, 274 32a b 39c d, 40c d 123. 174b. l 7 6 41a c 42a c 50a b P&FVPS Char ts . J o i n i n g No 8. 9. 10 and 11 APPLICABLE PROCESS ^.^^ f o l l o w i n g depending upon a p p l i c a t i o n ELECTRON BEAM WELDING TIG MIG PLASMA ARC Code 6 01 01 6 01 03 6 01 11 6 01 12 STATE OF THE ART ASSESSMENT The columblum and t a n t a l u m a l l o y s e x h i b i t good w e l d a b i l l t y i n bo t h sheet and p l a t e J o i n t e f f i c i e n c i e s o f n e a r l y 100 p e r c e n t are a t t a i n e d a t a l l temperatures Welding r e s u l t s i n a l o s s i n d u c t i l i t y i n a l l the a l l o y s as measured by the bend d u c t i l e t o b r i t t l e t r a n s i t i o n temperature E l e c t r o n beam w e l d i n g because o f i t s lower energy i n p u t produces welded j o i n t s w i t h s u b s t a n t i a l l y reduced l o s s i n d u c t i l i t y as compared w i t h TIG welds i n the columbium a l l o y s The t a n t a l u m a l l o y s are c o n s i d e r a b l y l e s s s e n s i t i v e t o w e l d i n g than are the columbium a l l o y s Vanadium and i t s a l l o y s are d u c t i l e a t room temperature a b i l i t y and should e x h i b i t good weld Chromium i s e x t r e m e l y b r i t t l e a t room temperature and n e i t h e r chromium nor i t s a l l o y s can be consid e r e d weldable i n comparison w i t h the columbium t a n t a l u m and vanadium a l l o y s I t s p o s i t i o n I n the p e r i o d i c t a b l e i n d i c a t e s t h a t i t w i l l behave l i k e molybdenum and t u n g s t e n as f a r as w e l d a b i l l t y i s concerned Molybdenum and i t s c u r r e n t a l l o y s are c h a r a c t e r i z e d by inadequate o x i d a t i o n r e s i s t a n c e a t hi g h tempe acures h i g h d u c t i l e t o b r i t t l e t r a n s i t i o n temperature ( i n the v i c i n i t y o f room temperature) and a moderate degree o f a n i s t r o p y The i n t e r s t i t i a l elements oxygen n i t r o g e n and carbon have a marked e f f e c t b o t h on the p a r e n t metal and on weld d u c t i l i t y An a p p r e c i a b l e body o f w e l d i n g experience e x i s t s f o r these r e f r a c t o r y metals and t h e i r c u r r e n t l y a v a i l a b l e a l l o y s R e f r a c t o r y metals have been Joined by n e a r l y a l l the known f u s i o n w e l d i n g processes The a v a i l a b l e data i s d i f f i c u l t t o c o r r e l a t e due t o wide v a r i a t i o n s i n base metal p r o p e r t i e s the unknown degree o f o p t i m i z a t i o n f o r a g i v e n process and v a r i a t i o n s i n t e s t i n g methods Pre h e a t i n g f o l l o w e d by immediate s t r e s s r e l i e f t r e a t m e n t w i l l p r o b a b l y p r e v e n t c r a c k i n g i n h i g h l y r e s t r a i n e d J o i n t s i n molybdenum t u n g s t e n and t h e i r h i g h e r s t r e n g t h a l l o y s These thermal t r e a t m e n t s w i l l have t o be accompanied by s u i t a b l e w e l d i n g procedures E l e c t r o n beam w e l d i n g i n hard vacuum i s p r o b a b l y the most d e s i r a b l e w e l d i n g process because o f i t s i n h e r e n t freedmn from c o n t a m i n a t i o n low energy i n p u t and the absence o f c o n v e c t i o n heat losses More Continued on nex t page ALTERNATE PROCESSES NONE Code
CHART 335 STATE OF THE ART ASSESSMENT, c o n t i n u e d work needs t o be done t o d e f i n e adequate s t r e s s r e l i e f thermal t r e a t m e n t s p a r t i c u l a r l y f o r t u n g s t e n weldments J o i n i n g d i s s i m i l a r r e f r a c t o r y metals may not r e p r e s e n t a major problem Several i n s t a n c e s have been r e p o r t e d where the v a r i o u s r e f r a c t o r y metals and a l l o y s have been f u s i o n welded (EB and TIG) t o d i s s i m i l a r metals and a l l o y s These i n c l u d e the combinations Mo t o W Cb a l l o y t o W and Ta t o W No p r o p e r t y data are a v a i l a b l e but i t i s assumed t h a t the j o i n t s were s a t i s f a c t o r y f o r the intended a p p l i c a t i o n The q u e s t i o n o f the p h y s i c a l and mechanical p r o p e r t i e s o f Che j o i n t compared t o those o f the base met a l i s p r o b a b l y the most d i f f i c u l t problem For example one of the major problems i n the use o f molybdenum i s i t s l a c k o f d u c t i l i t y a t temperatures near ambient The d i f f i c u l t i e s encountered w i t h b o t h wrought and r e c r y s t a l l i z e d molybdenum are increased by f u s i o n w e l d i n g The l a r g e g r a i n s produced d u r i n g w e l d i n g and the presence o f I m p u r i t i e s increase the d u c t i l e t o b r i t t l e t r a n s i t i o n temperature f o r a g i v e n m a t e r i a l as compared w i t h the same m a t e r i a l i n the as worked or r e c r y s t a l l i z e d c o n d i t i o n Bend t r a n s i t i o n temperatures r e p o r t e d f o r c o m m e r c i a l l y pure and molybdenum a l l o y welds i n t u n g s t e n have been r e p o r t e d i n the range o f 600 t o 1000 F T e n s i l e s t r e n g t h of welds i n tun g s t e n i s g e n e r a l l y lower than the base met a l up t o a temperature o f 2800 F Above these temperatures the J o i n t s t r e n g t h s are equal t o t h a t o f the base m a t e r i a l G r a i n growth and the g r e a t e f f e c t o f the i n t e r s t i t i a l elements account f o r the los s o f p r o p e r t i e s o f welded j o i n t s a t the lower temperatures i n Mo and W Improvement i n lower temperature mechanical p r o p e r t i e s may be p o s s i b l e by r e d u c i n g the q u a n t i t y o f the r e s i d u a l I n t e r s t i t i a l elements ( f o r example oxygen reduced t o l e s s than 1 ppm) and w i t h Improvements i n w e l d i n g technique I n t h i s c o n n e c t i o n e l e c t r o n beam w e l d i n g i s the most p r o m i s i n g o f the f u s i o n w e l d i n g processes The more c o n v e n t i o n a l processes such as TIG and MIG possess i n h e r e n t p h y s i c a l l i m i t a t i o n s which r e s t r i c t the choice o f process parameters L i m i t a t i o n s o f the same ord e r do not e x i s t w i t h the e l e c t r o n beam w e l d i n g process Furthermore the vacuum environment i s advantageous when w e l d i n g n e c e s s a r i l y h i g h p u r i t y base met a l which I s so h i g h l y r e a c t i v e i n na t u r e F i n a l l y none o f the s t r u c t u r e s c o n s i d e r e d are e x c e s s i v e l y l a r g e f o r e l e c t r o n beam w e l d i n g i n vacuum CONCLUSIONS AND RECOMMENDATIONS 1 A d u c t i l e weldable chromium a l l o y must be developed t o meet the AARP requirements S u r v e i l l a n c e o f a l l o y development i s i n o r d e r ( A u s t r a l i a n work f o r example) and a w e l d i n g program I n i t i a t e d when a p r o m i s i n g a l l o y emerges 2 No m a n u f a c t u r i n g development a c t i o n i s recommended f o r f u s i o n w e l d i n g o f present molyb denum and tu n g s t e n a l l o y s which cannot be j o i n e d by f u s i o n w e l d i n g w i t h o u t a l o s s o f d u c t i l i t y a t temperatures near ambient 3 Weldable t u n g s t e n and molybdenum a l l o y s should be developed The tun g s t e n molybdenum and the tun g s t e n rhenium systems seem t o o f f e r promise As an i n d i c a t o r o f the degree o f w e l d a b l l i t y which should be the reasonable g o a l i t i s proposed t h a t e x t r e m e l y h i g h p u r i t y t u n g s t e n ( p u r i t y as achieved f o r semi conductor m a t e r i a l s ) be produced and s u b j e c t e d t o w e l d i n g under the most f a v o r a b l e c o n t a m i n a t i o n f r e e c o n d i t i o n s e l e c t r o n beam f u s i o n w e l d i n g i n a hard vacuum w i t h subsequent t e s t s t o determine whether the d u c t i l e b r i t t l e t r a n s i t i o n tempera t u r e has been a p p r e c i a b l y increased 4 When a l l o y s o f f e r i n g enhanced w e l d a b l l i t y become a v a i l a b l e i t i s recommended t h a t e a r l y a t t e n t i o n be devoted t o development of post weld thermal t r e a t m e n t s f o r e f f e c t i v e s t r e s s r e l i e f o f complex weldments
336 TITLE FUSION WELDING HIGH STRENGTH ALUMINUM ALLOY CHART PRIORITY RELATED CAMR MANUFACTURING REQUIREMENT Fusion weld s o l i d p r o p e l l e n t motor cases c o n s t r u c t e d o f 2014 aluminum a l l o y 1 i n c h t h i c k Case I s 4 f e e t diameter by 10 f e e t long Weld j o i n t e f f i c i e n c y o f 95 p e r c e n t i s the s t a t e d r equirement AARP REFERENCES E r k . ^ . 138 R rhâH. 65b 69b 71b PXFVPS Charts . APPLICABLE PROCESS Code ELECTRON BEAM WELDING 6 01 12 STATE O F THE ART ASSESSMENT A r e c e n t l y completed p r o d u c i b i l l t y program and i m p l e m e n t a t i o n I n s e r i a l p r o d u c t i o n o f a l i q u i d f u e l m i s s i l e has demonstrated the s u p e r i o r i t y o f e l e c t r o n beam w e l d i n g f o r h i g h s t r e n g t h aluminum a l l o y s The m a t e r i a l o f c o n s t r u c t i o n was 2014 T651 e x h i b i t i n g the f o l l o w i n g p r o p e r t i e s UTS 70 000 p a l YS 60 000 p s i E l o n g a t i o n 13% i n 2 inches The maximum as-welded p r o p e r t i e s a t t a i n e d w i t h TIG (GTA) w e l d i n g are as f o l l o w s ( t e s t e d a f t e r 160 hours n a t u r a l aging ) UIS 48 000 p s l YS 29 000 p s i E l o n g a t i o n 6 57 i n 1 i n c h (69 p e r c e n t weld J o i n t e f f i c i e n c y ) I n d e v e l o p i n g e l e c t r o n beam w e l d i n g parameters f o r t h i s a l l o y i t was found t h a t maximum t e n s i l e s t r e n g t h was a t t a i n e d a t a w e l d i n g speed o f 40 IPM t h a t y i e l d s t r e n g t h c o n t i n u e d t o incr e a s e as speed i n c r e a s e d but t e n s i l e s t r e n g t h reduced A t w e l d i n g speeds i n excess o f 80 IPM m i c r o c r a c k i n g o c c u r r e d i n the f u s i o n and heat a f f e c t e d zones As welded p r o p e r t i e s a t t a i n e d I n 0 535 i n c h t h i c k 2014 T651 e l e c t r o n beam welded a t 40 IPM t e s t e d a f t e r 160 hours n a t u r a l aging are as f o l l o w s UTS 55 333 p s l YS 47 900 p s l E l o n g a t i o n 47 i n 1 i n c h (80 p e r c e n t weld j o i n t e f f i c i e n c y ) These mechanical p r o p e r t i e s were found t o be Independent o f p l a t e t h i c k n e s s over the range I n v e s t i g a t e d (0 250 t o 0 535 Inches) Transverse shrinkage was l e s s than 0 005 i n c h and was r e p r o d u c i b l e which p e r m i t t e d a c c u r a t e c o n t r o l o f f i n a l m i s s i l e dimensions even though f i v e s t r u c t u r a l g i r t h welds were r e q u i r e d I t i s expected t h a t s h r i n k a g e w i l l not exceed 0 005 inches when b u t t w e l d i n g 1 i n c h t h i c k n e s s Continued on next page ALTERNATE PROCESSES NONE Code
CHART 337- STATE-OF THE ART ASSESSMENT c o n t i n u e d The e l e c t r o n beam weld p r o p e r t i e s s t a t e d above do not meet the AARP s t a t e d r e q u i r e m e n t s a l t h o u g h they made i t p o s s i b l e t o e l i m i n a t e the lands on the two b a r r e l s e c t i o n s o f the p a r t i c u l a r m i s s i l e i n v o l v e d However p r e l i m i n a r y i n v e s t i g a t i o n r e v e a l e d s e v e r a l methods f o r e f f e c t i n g improvement i n the weld p r o p e r t i e s a t t a i n e d 1 C o n t r o l p r o p e r t i e s o f m a t e r i a l p r i o r t o w e l d i n g For example s u b s t i t u t i n g 2014 T6 f o r 2014 T651 r e s u l t e d i n a g a i n o f 5000 p s i i n Uts 2 An a d d i t i o n a l 2000 p s i i n y i e l d somewhat l e s s i n Uts was gained by a r t i f i c i a l a ging a t 350F f o r 8 hours 3 Making the weld a t a s l i g h t angle increased Uts A t 7° t o v e r t i c a l t h e g a i n i n Uts was about 1000 p s i The optimum angle appears somewhere between the l i m i t s 0 t o 45° I t I s a n t i c i p a t e d t h a t r e f i n e m e n t i n e l e c t r o n beam w e l d i n g technique and i n base metal p r i o r h i s t o r y w i l l p r o v i d e s u f f i c i e n t g a i n s i n mechanical p r o p e r t i e s t o meet the d e s i g n r e q u i r e m e n t s o f a s o l i d f u e l motor case c o n s t r u c t e d o f 2014 aluminum a l l o y by means o f e l e c t r o n beam w e l d i n g A l t h o u g h the AARP requirement i s expressed s i m p l y i n terms o f j o i n t e f f i c i e n c y the a c t u a l d e s i g n c r i t e r i a w i l l I n c l u d e y i e l d s t r e n g t h and bend s t r e n g t h The w e l d i n g parameters can be J u d i c i o u s l y s e l e c t e d t o o b t a i n the optimum v a l u e o f the more c r i t i c a l p r o p e r t y
338 TITLE FUSION WELDING CLAD SHEET AND FOIL CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT J o i n by f u s i o n w e l d i n g d e t a i l p a r t s and honeycomb pan e l edge members o f s t a i n l e s s s t e e l and n i c k e l base s u p e r a l l o y s c l a d w i t h g o l d p l a t i n u m rhodium and t a n t a l u m Fusion welded j o i n t s must m a i n t a i n c o r r o s i o n r e s i s t a n c e i n th e weld J o i n t area by p r e v e n t i n g i n t e r d i f f u s i o n between c l a d d i n g and base met a l Requirements I n c l u d e c o r r o s i o n r e s i s t a n c e t o h i g h e f f i c i e n c y f u e l t o exhaust f r o m f l u o r i n e f u e l s and e r o s i o n r e s i s t a n c e F a t i g u e a c o u s t i c n o i s e t o 180 db and e t r e s s r u p t u r e are key requirements T y p i c a l a p p l i c a t i o n s are ( 1 ) i n t e g r a l tanks and t i p tanks o f 0 COS t o 0 093 Inches t h i c k n e s s formed from sheets up t o 8 f e e t by 12 f e e t (2) j o i n i n g edge members t o aerodynamic l i f t and c o n t r o l s u r f a c e s o f honeycomb panels w i t h c l a d o u t e r s k i n Panels are up t o 12 f e e t square contoured aerodynamic shapes down t o 1 f o o t r a d i u s ( 3 ) v e c t o r c o n t r o l and t h r u s t d e f l e c t o r c o n s i s t i n g i n up t o 12 f e e t square contoured aerodynamic shape honey comb panels w i t h f a c i n g t h i c k n e s s t o 0 050 i n c h and c l a d d i n g t o 0 003 i n c h t h i c k n e s s AARP REFERENCES e r k - . > . U R Chart. l a 3 4 PAFVPS Charts APPLICABLE PROCESS 6 01 12 15 ELECTRON BEAM LASER PLASMA ARC TIG and MIG WELDING 6 01 11 6 01 01 6 01 03 STATE O F THE ART ASSESSMENT I n p r o b a b l y every case c l a d d i n g must be removed b e f o r e the core m e t a l i s f u s i o n welded and the c l a d d i n g r e p l a c e d Removal of the c l a d w i t h o u t t h i n n i n g the core might prove t o be a problem i f chemical methods are i n e f f e c t i v e and some form o f c u t t i n g t e c h n i q u e i s necessary I t would be advantageous t o u t i l i z e a low energy i n p u t process f o r the core m e t a l J o i n t where the m a t e r i a l s ( c o r e and c l a d ) e x h i b i t a l a r g e d i f f e r e n c e i n thermal c o n d u c t i v i t y and expansion i n t r o d u c i n g the p o s s i b i l i t y o f b l i s t e r i n g and c l a d d i n g s e p a r a t i o n The w e l d i n g processes I n the o r d e r o f energy i n p u t are Low energy i n p u t Laser and E l e c t r o n Beam However the former i s l i m i t e d t o t h i n n e r gauges than t h i s r e quirement High energy i n p u t Plasa arc MIG TIG MIG i s not s u i t a b l e f o r the t h i n gauge core w e l d i n g b u t would be u s e f u l f o r J o i n t b u t t e r i n g The c l a d can be r e p l a c e d by b u t t e r i n g 1 e f i l l i n g the groove produced by c l a d removal w i t h f i l l e r w i r e o f c l a d d i n g c o m p o s i t i o n and low power s e t t i n g s I n t e r d i f f u s i o n must be guarded a g a i n s t Where a e r o d y n a m i c a l l y a c c e p t a b l e the core J o i n t can be covered by a cap s t r i p o f c l a d d i n g c o m p o s i t i o n lap or f i l l e t welded t o the c l a d d i n g T h i s w i l l r e q u i r e the e l e c t r o n beam or the l a s e r energy source S a t i s f a c t o r y s o l u t i o n s t o the c l a d sheet and f o i l j o i n i n g problems w i l l e v o l v e as the need a r i s e s No development program i s recommended CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Cede
339 TITLE DIFFUSION BONDING OF CERAMIC OR GRAPHITE BEARING INSERT TO REFRACTORY METAL STRUCTURE FOR HIGHLY LOADED CONTROL SURFACE PIVOT MECHANISMS CHART N O RELATED PRIORITY CAMR CHARTS MANUFACTURING REQUIREMENT To d i f f u s i o n bond b e a r i n g s u r f a c e s o f ceramic or g r a p h i t e t o t u n g s t e n or t a n t a l u m b e a r i n g r e t a i n e r s t r u c t u r e s f o r l i f t e n t r y v e h i c l e c o n t r o l s u r f a c e p i v o t mechanisms S e r v i c e temperatures c o u l d range from 250F t o 3500F w i t h major loads expected between lOOOF and 3000F Re use c a p a b i l i t y d e s i r e d Design may i n v o l v e no l u b r i c a t i o n or co u l d i n c o r p o r a t e some unique l u b r i c a t i o n system p e c u l i a r t o the s p e c i f i c a p p l i c a t i o n AARP REFERENCES F r i i n r t i 277 B C h a r t i 126a P A F V P « f h n r t . APPLICABLE PROCESS Code CREEP CONTROLLED DIFFUSION BONDING USING LOW PRESSURE AND LONG TIME 6 09 02 STATE OF THE ART ASSESSMENT The s t u d i e s o f bearings bearing m a t e r i a l s and bearing l u b r i c a n t s for space and r e entry systems has been e x t e n s i v e L i q u i d and a i r systems a r e t h e most p r o m i s i n g where l u b r i c a n t c o n t a m i n a t i o n or change i n c h a r a c t e r i s t i c s are n o t problems The c o n s i d e r a t i o n o f ceramic and g r a p h i t e b e a r i n g s as i n t h i s a p p l i c a t i o n i s o n l y one of many s e r i o u s approaches t o the problem Ceramic m a t e r i a l s have been d i f f u s i o n bonded t o t u n g s t e n and t a n t a l u m but f a i l u r e s have oc c u r r e d i n the ceramic due t o thermal expansion mismatch d u r i n g c o o l i n g G r a p h i t e s have been t r i e d on a l i m i t e d s c a l e Both t a n t a l u m and t u n g s t e n have been d i f f u s i o n bonded t o themselves on a developmental b a s i s No m a n u f a c t u r i n g development program t o f i t t h i s s p e c i f i c a p p l i c a t i o n i s recommended sin c e i t i s b e l i e v e d t h a t a l t e r n a t e d e s i g n concepts would be developed The r e s u l t s o f d l f f u s i o r j bonding e f f o r t under CAMR 432 would be o f b e n e f i t t f t h i s d i s s i m i l a r m a t e r i a l concept were found mandatory CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Code
340 TITLE DEVELOPMENT OF ADHESIVES AND APPLICATIONS TECHNIQUES FOR INSULATING AND ABLATIVE SYSTEMS FOR ROCKET CHAMBERS AND NOZZLES CHART N O PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Apply o r g a n i c compounds m i x t u r e s o f o r g a n i c s and non m e t a l l i c s or c e r a m i c / r e f r a c t o r y m e t a l m a t r i c e s impregnated w i t h a b l a t i v e m a t e r i a l s t o r o c k e t engine n o z z l e s and chamber s t r u c t u r a l members Sizes range from 30 i n c h diameter x 5 feet t o 40 feet diameter x 160 feet I n l e n g t h AARP REFERENCES E Chart! B Charts PSFVPS rhârt. J o i n i n g No 1 APPLICABLE PROCESS ADHESIVE BONDING STATE-OF THE ART ASSESSMENT Code P r e s e n t r o c k e t chamber technology r e q u i r e s t h a t i n s u l a t i n g b l a n k e t s be used t o p r o t e c t the chambers from the heat o f combustion through the f i r i n g c y c l e Advanced work i s aimed a t p r o t e c t i o n s u f f i c i e n t t o p e r m i t reuse o f the chambers f o r t e s t f i r i n g s and i n r e c o v e r a b l e systems I n s u l a t i n g b l a n k e t s are rubber compounds t o which may be added b o r i c a c i d f i b e r asbestos and o t h e r low heat c o n d u c t i o n m a t e r i a l s To the I n s u l a t i o n f o r s o l i d s i s u s u a l l y a t t a c h e d a l i n e r t o w h i c h the p r o p e l l a n t mass i s adhered t o p r o v i d e support The adhesives may be rubber base epoxles polyamides or s i m i l a r o r g a n i c compounds The i d e a l system i s l i g h t i n w e i g h t r e a d i l y produced and i n s t a l l e d w i t h a h i g h degree o f r e l i a b i l i t y w hich w i l l a b l a t e or char but n o t be f u l l y p e n e t r a t e d Rocket no z z l e s have been made o f combinations o f p r a c t i c a l l y every known aerospace m a t e r i a l These range from i n f i l t r a t e d t u n g s t e n t o layups o f g r a p h i t e impregnated c l o t h and p h e n o l l c s w i t h t h r o a t i n s e r t s of ceramics and cermets For each o f these a p p l i c a t i o n s the adhesives used i n bonding p l a y an i m p o r t a n t r o l e As the s m a l l chambers are a l l o w e d t o g e t h o t t e r through the use o f t r o n g e r xmre heat r e s i s t a n t a l l o y s and m a t e r i a l s and as the s i z e and mass of the l a r g e boo t-pr p r o p e l l a n t s grow a new f a m i l y o f adhesives w i l l r e q u i r e development These new adhesives w i l l cause changes i n a p p l i c a t i o n methods and p o s s i b l y i n NDT t e c h n i q u e s Combining a b l a t o r s w i t h m e t a l l i c c6mpoiinds to r a i s e the heat r e s i s t a n c e w i l l a f f e c t the a b i l i t y t o spray i n p l a c e and a l t e r n a t i v e s o f c a s t i n g or t r o w e l i n g i n p l a c e may lead t o new problems and h i g h c o s t s I t i s b e l i e v e d t h a t e x i s t i n g adhesive systems and a p p l i c a t i o n techniques are s a t i s f a c t o r y f o r a b l a t i v e m a t e r i a l s and c u r r e n t d e s i g n concepts and no m a n u f a c t u r i n g development program i s proposed f o r the e x t e n s i o n o f t h i s c u r r e n t technology However the e f f o r t t o achieve more p r e c i s e l y f o r m u l a t e d a b l a t i v e systems f o r p r o p u l s i o n a p p l i c a t i o n s t a i l o r e d t o the p r o p e l l a n t combustion environment r a t h e r than t o r e e n t r y c o n d i t i o n s may lead t o unusual c o m p o s i t i o n s which Cannot be e f f e c t i v e l y bonded w i t h c u r r e n t adhesives F a b r i c a t i o n t r i a l s t o v e r i f y such a problem and t o examine new adhesives or a p p l i c a t i o n techniques may be warranted i n the f u t u r e as a r e s u l t of such m a t e r i a l s development ALTERNATE PROCESSES NONE Code
-341 TITLE BALL AND SOCKET JOINT FOR SPACE SUIT CHART PRIORITY N O yy/ RELATED CAMR CHARTS MANUFACTURING REQUIREMENT T h i s i s a space s u i t r e quirement f o r I n d i v i d u a l use As such appendage components f o r arms l e g s hands head w i l l be custom f i t t e d The l i g h t w e i g h t s u i t (30 45 l b s ) must be capable o f being e n t e r e d or removed by the i n d i v i d u a l w i t h o u t a s s i s t a n c e The a b i l i t y t o f e e l t h r o u g h the gloved hand i s e s s e n t i a l I n g e n e r a l the s u i t made o f woven and coated m e t a l l l c s f o r maximum f l e x i b i l i t y ( p r o b a b l y t i t a n i u m or t i t a n i u m based a l l o y s ) w i l l be s u b j e c t t o the r m a l unbalance r e p r e s s u r i z a t i o n ( t o 7 p s i ) w i t h the severe problem o f p o s s i b l e t e a r s and punctures as w e l l as long p e r i o d s o f st o r a g e J o i n t s w i l l be b a l l and socket type f a b r i c a t e d from m e t a l ( t i t a n i u m ) and p o l y t e t r a f l u o r o e t h y l e n e coated f o r ease o f movement d u r i n g t h e v a r y i n g t h e r m a l and p r e s s u r e c o n d i t i o n s o f space o p e r a t i o n I t w i l l be necessary among o t h e r m a n u f a c t u r i n g r e q u i r e m e n t s t o f a s t e n o r a t t a c h t h e b a l l and socket h a l v e s t o the woven m e t a l l i c space s u i t AARP REFERENCES E Charts B Charts Ul± PSFVPS C h a r t s . APPLICABLE PROCESS Code STATE O F THE ART ASSESSMENT At p r e s e n t space s u i t s are t o o heavy l a c k adequate f l e x i b i l i t y and s e n s i t i v i t y The b a l l and socket J o i n t s though low i n t o r q u e have r e s t r i c t i o n s which l i m i t normal human motions and cause an inc r e a s e i n body temperature and excessive f a t i g u e The user cannot e n t e r secure or remove the space s u i t w i t h o u t a s s i s t a n c e The s t a t e o f the a r t i s l i m i t e d t o the s u i t a b i l i t y o f a v a i l a b l e m a t e r i a l s The m a n u f a c t u r i n g techniques needed t o f a s t e n components ( b r a z i n g w e l d i n g adheslves e t c ) are c u r r e n t l y w e l l understood and new methods processes and Improvements t o the e x i s t i n g techniques ale c o n t i n u a l l y added t o our technology The experiences o f the Gemini a s t r o n a u t s are being a p p l i e d t o the A p o l l o program i n the form o f b a s i c d e s i g n s t u d i e s on l i g h t w e i g h t approaches t o conserve s t r e n g t h w h i l e a l l o w i n g freedom o f movement U n t i l d e s i g n c r i t e r i a are more c l e a r l y d e f i n e d and a need f o r a new m a t e r i a l or process develops no program i s recommended CRITICAL PROBLEMS NONE ALTERNATE PROCESSES | Code NONE
342 TITLE ASSEMBLY OF LANDING SKID DESIGNED TO PRODUCE FRICTIONAL FORCES FOR DECELERATION CHART PRIORITY RELATED CAMR CHARTS MANUFACTURING REQUIREMENT The p o t e n t i a l d e s i g n concept e n v i s i o n s brush l i k e pads composed of 0 100 diameter s u p e r a l l o y w i r e ( b e r y l l i u m t u n g s t e n n i t l n o l moly e t c ) b r i s t l e s a p p r o x i m a t e l y 3 0 inches l o n g brazed or welded i n a dense arrangement which w i l l produce u n i f o r m l y d i s t r i b u t e d f r i c t i o n s c a t t e r c h a r a c t e r i s t i c s The r e s u l t a n t assembly must have j o i n t s t r e n g t h s (shear t e n s i o n ) t o endure the h i g h dynamic s t r e s s e s o f l a n d i n g on a v a r i e t y o f s u r f a c e s as w e l l as the th e r m a l (1800F 1 hr ) though unstressed environment w h i l e i n the s t o r e d i n f l i g h t p o s i t i o n AARP REFERENCES E Charts 311 B Cherts P&FVP5 C h a r t s . APPLICABLE PROCESS BRAZING Code 6 05 00 STATE O F THE ART ASSESSMENT Depending on the des i g n approach t h i s requirement w i l l i n v o l v e J o i n i n g b r i s t l e l i k e s u p e r a l l o y d e t a i l s t o each o t h e r or by j o i n i n g them t o a p l a t f o r m s t r u c t u r e I n the f i r s t concept i t i s c o n c e i v a b l e t h a t the base or shank of the b r i s t l e would c o n s i s t o f prepared shapes square or o t h e r w i s e which when brazed bundle l i k e would g e o m e t r i c a l l y assure concurrence w i t h r e q u i r e d c e n t e r t o c e n t e r d i s t a n c e s As an a l t e r n a t e the shanks would be prepared w i t h i n t e r l o c k i n g s u r f a c e s t o accomplish the f o r e g o i n g but would add mechanical s t r e n g t h t o t h a t o f the braze I n the second i n s t a n c e i t i s necessary t o prepare a p l a t f o r m e i t h e r by d r i l l i n g b o r i n g or o t h e r w i s e p e r f o r a t i n g t o accept the b r i s t l e shanks I n bo t h circumstances b r a z i n g i s an ac c e p t a b l e metal j o i n i n g approach The s t a t e o f the b r a z i n g a r t i s such t h a t t h i s r e q u i r e m e n t i s w i t h i n the reach o f the pre s e n t or near f u t u r e c a p a b i l i t i e s The t e c h n o l o g y o f vacuum b r a z i n g atmosphere b r a z i n g f i t u p s s u r f a c e p r e p a r a t i o n as w e l l as a v a r i e t y o f heat source r e s o u r c e s i s w e l l understood There i s a need f o r c o n t i n u i n g d e s i g n and development o f h i g h temperature b r a z i n g a l l o y s based on e i t h e r i n i t i a l l y h i g h m e l t temperatures or as an a l t e r n a t e h i g h r e m e l t temperature However c o n s i d e r a b l e p r o g r e s s i s being made i n t h i s f i e l d and p r e s e n t r a t e o f accomplishments should assure the a v a i l a b i l i t y o f a s u i t a b l e b r a z i n g a l l o y w i t h i n the next 6 10 years A l t e r n a t e approach would be t o develop a semi automatic system o f f l a s h ( r e s i s t a n c e ) up set w e l d i n g T M c h has been t r i e d s u c c e s s f u l l y on e l e c t r i c a l conductors I t w i l l be necessary t o develop h i g h temperature b r a z i n g a l l o y s which a t the 1800 F ( 1 h r ) i n f l i g h t ( s t o r a g e d ) p o s i t i o n w i l l n o t r e m e l t and which w i l l possess s u f f i c i e n t s t r e n g t h t o p r o t e c t and assure the i n t e g r i t y o f the sklcj assembly Such a l l o y s w i l l undoubtedly come out o f the CAMR recommendations d e t a i l e d on ot h p r c h a r t s T h e r e f o r e no program i s suggested here ALTERNATE PROCESSES NONE Code
-343 TITLE RESISTANCE WELDING OF HONEYCOMB CORE CHART PRIORITY N O ^ y y RELATED CAMR CHARTS MANUFACTURING REQUIREMENT Resistance spot w e l d i n g I s r e q u i r e d f o r s p l i c i n g c e l l u l a r honeycomb core o f aluminum and beta t i t a n i u m a l l o y s C e l l u l a r core i s 1/2 i n c h t o 2 Inches deep The s p l i c i n g must be h e l d t o v e r y c l o s e t o l e r a n c e s f o r subsequent i n c o r p o r a t i o n i n t o curved honeycomb bonded or brazed assemblies 50 f e e t long by 60 f e e t i n diameter A p p l i c a t i o n s are f o r boosters and the I n t e r stages and tanks o f space v e h i c l e s AARP REFERENCES E Charts L S i IBS- B Charts 50a ⢠84. 97b P&FVPS C h a r t s . APPLICABLE PROCESS I Code RESISTANCE SPOT WELDING I 6 02 01 STATE-OF THE ART ASSESSMENT The manufacture o f unexpanded honeycomb core I s on an automated b a s i s Aluminum u n a l l o y e d t i t a n i u m and p r e c i p i t a t i o n s trengthened s t e e l a l l o y s are a l l so produced However the s i z e s r e q u i r e d f o r l a r g e v e h i c l e components and changes i n c o n f i g u r a t i o n w i t h i n these components make i t necessary t o s p l i c e the c o r e d u r i n g assembly S p l i c e s may i n v o l v e d i s s i m i l a r core c e l l s i z e s i n l o c a l areas These c e l l u l a r core d e t a i l s have been Joined w i t h tong type guns u s i n g b o t h AC power and condenser d i s c h a r g e p u l s e s w i t h pressure bei,ng s u p p l i e d by a i r s p r i n g or manual means Due t o the d i f f i c u l t y o f f i t t i n g and h o l d i n g the d e t a i l s i n i n t i m a t e c o n t a c t and the l a c k o f a c c e s s i b i l i t y due t o the l i m i t e d space o f the cores makes the moving and l o c a t i n g o f the tongs a t i m e consuming i n e f f i c i e n t o p e r a t i o n As the cores must be l o c a t e d and h e l d t o w i t h i n a h e i g h t t o l e r a n c e o f ± 0 003 Inches machining o f t h e cores must be accomplished a f t e r c o m p l e t i o n o f the w e l d i n g o p e r a t i o n I t i s reasonable t o assume t h a t the aut o m a t i c equipment now I n use t o produce unexpanded core can be Increased t o d e l i v e r l a r g e r s l s e s and t h a t the p r i n c i p l e s used can be a p p l i e d t o s p l i c i n g on assembly w i t h a h i g h degree o f accuracy as the demand d i c t a t e s The use o f a lo n g bar e l e c t r o d e i n c o n n e c t i o n w i t h a c o n v e n t i o n a l e x t e r n a l e l e c t r o d e has been demonstrated as f e a s i b l e f o r J o i n i n g the d e t a i l s o f t r u s s typo s t r u c t u r e s and w i t h some d e s i g n m o d i f i c a t i o n s should be a p p l i c a b l e here The unanswered q u e s t i o n i s whether such methods are a p p l i c a b l e t o a l l o y s r e q u i r i n g h i g h e n e r g i e s and pres s u r e s t o c r e a t e a J o i n t I t i s b e l i e v e d t h a t t h i s I n f o r m a t i o n would be gathered b e f o r e a p p l i c a t i o n s a r i s e i n v o l v i n g r e s i s t a n c e w e l d i n g f o r core s p l i c i n g ALTERNATE PROCESSES | ^od7 NONE
344 TITLE CHART PRIORITY RESISTANCE WELDING REFRACTORY ALLOYS N O *f^S MANUFACTURING REQUIREMENT M e t a l l u r g l c a l l y sound r e s i s t a n c e spot and seam welds are r e q u i r e d i n r e f r a c t o r y a l l o y s columblum molybdenum t a n t a l u m t u n g s t e n and p o s s i b l y vanadium i f d e s i r a b l e a l l o y s emerge i n f o i l and sheet gauges from 0 002 i n c h t o 0 120 i n c h A p p l i c a t i o n s are f o r l e a d i n g edges and nose cones f o r h y p e r s o n i c v e h i c l e s heat s h i e l d s f o r l i f t r e e n t r y v e h i c l e s r a m j e t d l f f u s e r l e a d i n g edges Components o p e r a t e at h i g h temperatures i n an o x i d i z i n g atmosphere w i t h temperatures r a n g i n g f r o m 2000 F t o 5000 P and a t a c o u s t i c l e v e l s from 140 t o 190 db Components would be coated f o r o x l d a t l o n - e r o e l o n p r o t e c t i o n w i t h s i l l c l d e a l u m i n i d e n i t r i d e or o x i d e ceramic type d i f f u s i o n c o a t i n g s AARP REFERENCES 57 59 67 88 90 96 117 264 E Charts g C h a r t . 28c d 29b c 30a 31a 32a 39c 40c d 41a 42a c 50a 51b 120a c 121a P i F V P S r h n r t . J o i n i n g No 8 APPLICABLE PROCESS RESISTANCE SPOT AND SEAM WELDING Code 6 02 01 STATE OF THE ART ASSESSMENT Coatings must be removed p r i o r t o j o i n i n g as they are not amenable t o passage o f the c u r r e n t and do n o t a l l o w f o r m a t i o n o f the j o i n t a t the f a y i n g s u r f a c e s Resistance spot weld have been produced I n some a l l o y s o f Ta and Cb whose mechanical p r o p e r t i e s were s a t i s f a c t o r y f o r the Intended a p p l i c a t i o n Welds i n o t h e r a l l o y s o f Ta and Cb have p r o p e r t i e s t o o low when compared t o the base m e t a l p a r t i c u l a r l y i n c r o s s t e n s i o n s t r e n g t h and f a t i g u e p r o p e r t i e s Welds i n a l l o y e d Mo and W are c o m p l e t e l y u n s a t i s f a c t o r y due t o t h e i r low mechanical p r o p e r t i e s The e x p l o s i v e w e l d i n g process has been used t o j o i n W sheet t o a s t e e l s u b s t r a t e and TzM Mo a l l o y has a l s o been s u c c e s s f u l l y Joined Whether t h i s process i s v e r s a t i l e and f l e x i b l e enough t o ap p l y t o l i g h t s t r u c t u r e s remains t o be seen and c u r r e n t work i s d i r e c t e d t o t h i s end A e r o j e t - G e n e r a l and SRI are c o n d u c t i n g such s t u d i e s The h i g h c u r r e n t s and pressure d e n s i t i e s r e q u i r e d t o weld the s t i f f e r and h i g h e r tempera t u r e a l l o y s r a p i d l y degrade the normal copper e l e c t r o d e s and m e l t i n g f o l l o w e d by s t i c k i n g i s a common occurrence Some work has been done I n t h i s area u s i n g h i g h e r temperature m a t e r i a l s and c r y o g e n i c c o o l i n g C o n t i n u a t i o n o f p r e s e n t e f f o r t should g i v e the needed c a p a b i l i t y by 1970 but some m a t e r i a l s development may be i n d i c a t e d Resistance w e l d i n g equipment i s being u t i l i z e d f o r some d i f f u s i o n bonding e x p e r i m e n t a l work t a k i n g advantage o f the c l o s e c o n t r o l which can be e x e r c i s e d t h r o u g h the equipment c i r c u i t r y I t i s suggested t h a t t h i s be co n s i d e r e d from a m a n u f a c t u r i n g sense as a s p e c i a l case o f the d i f f u s i o n bonding programs f o r r e f r a c t o r y a l l o y s o u t l i n e d under CAMR 432 437 and 438 and no f u r t h e r development i s proposed f o r the spot and seam aspects alone ALTERNATE PROCESSES DIFFUSION SPOT BONDING DIFFUSION SPOT WELDING Code 6 09 00 6 03 02
345 TITLE RESISTANCE WELDING DISPERSION STRENGTHENED SUPERALLOYS CHART PRIORITY N O MANUFACTURING REQUIREMENT M e t a l l u r g i c a l l y sound spotwelds and seam welds are d e s i r e d i n d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y components such as s k i n s t r i n g e r assemblies d u c t i n g and a i r f o i l s I n v o l v i n g gauges from 0 010 i n c h t o 0 120 in c h A p p l i c a t i o n s i n v o l v e s e r v i c e temperatures to 2300F AARP REFERENCES F ct,^^. 27 58 59 89 95 116 271 B C h o r t . ^^'^ 30c 31c 32b 41a 42c 50a b 51b 52a 122b P4FVPS Charts T n l n i n g u o . 17 APPLICABLE PROCESS Code RESISTANCE SPOT WELDING (DIFFUSION BONDING) 6 02 01/6 09 00 STATE O F THE ART ASSESSMENT C o n v e n t i o n a l r e s i s t a n c e spot w e l d i n g o f d i s p e r s i o n s t r e n g t h e n e d s u p e r a l l o y s g i v e s poor mechanical p r o p e r t i e s f o r the J o i n t because o f the agg l o m e r a t i o n o f s t r e n g t h e n i n g d i s p e r s e d p a r t i c l e s as the nugget raches the m e l t i n g p o i n t S t r e n g t h s are low shear v a l u e s are non u n i f o r m and f a t i g u e v a l u e s are low G r a i n growth and c r a c k i n g are observed D i f f u s i o n bonding i n v e s t i g a t i o n s are being conducted using a v a r i e t y o f time temperature pressure parameters i n c l u d i n g the use o f spot w e l d i n g equipment t o p r o v i d e heat and pressure From the data developed t o date a d a p t a t i o n o f r e s i s t a n c e welders as an energy and pressure source which can be c l o s e l y c o n t r o l l e d appears f e a s i b l e I t i s suggested t h a t the CAMR 436 proposed development program on d i f f u s i o n bonding o f d i s p e r s i o n strengthened s u p e r a l l o y s extend c u r r e n t work c o n s i d e r i n g two p o s s i b i l i t i e s r e l a t e d t o r e s i s t a n c e w e l d i n g equipment 1 Low energy f o r an extended time p e r i o d wherein the fused zone would approach zero and the J o i n t more n e a r l y approach a bond 2 An u l t r a h i g h energy wave of u l t r a s h o r t d u r a t i o n w h e r e i n the fused zone would approach zero and the time would be too s h o r t f o r a p p r e c i a b l e p a r t i c l e s e p a r a t i o n No program e x c l u s i v e l y on r e s i s t a n c e w e l d i n g o f d i s p e r s i o n strengthened s u p e r a l l o y s i s recommended CAMR c h a r t 424 on f u s i o n w e l d i n g o f these a l l o y s d i s c u s s e s the need f o r a b e t t e r u n d e r s t a n d i n g o f the ag g l o m e r a t i o n o f d i s p e r s o i d and the d e s i r e f o r a l l o y s which a r e n o t so impaired by h e a t i n g t o the f u s i o n temperature or c l o s e t o i t A s i m i l a r o b j e c t i v e f o r a l l o y s which can be c a s t i s mentioned i n the Base Metal Forms panel r e p o r t CRITICAL PROBLEMS NONE ALTERNATE PROCESSES NONE Code
-346 TITLE RESISTAHCE NBLOING OF LARCE STRUCTURES CHART NO PRIORITY RELATED CAMR CHARTS ^33 no I MANUFACTURING REQUIREMENT Resistance spot w e l d i n g i s r e q u i r e d f o r J o i n i n g 0 030 i n c h s t i f f e n i n g members t o 0 010 i n c h sheet o f p r e c i p i t a t i o n strengthened s u p e r a l l o y and 0 020 Inch 0 100 i n c h s t i f f e n i n g members t o 0 010 i n c h - 0 030 In c h sheet o f beta t i t a n i u m a l l o y i n s t r u c t u r e s o f 60 f e e t + 0 16 In c h I n diameter and 60 f e e t + 1 0 i n c h long AARP REFERENCES U 2 . E Char ts . B Charts . lAft 1«7. 271 49. 92. 97a. 122b P4FVPS ru,,.. J o i n i n g No L APPLICABLE PROCESS RESISTANCE SPOT WELDING Code 6 02 01 STATE OF THE ART ASSESSMENT Resistance spot w e l d i n g o f the a p e c i f i e d gauges f o r those m a t e r i a l s t o MIL standards i s s t a t e o f the a r t To assemble and h o l d the d e t a i l s t o the s p e c i f i e d t o l e r a n c e s o n l y r e q u i r e s accurate assembly f i x t u r e s and should be consid e r e d s t a t e o f the a r t f o r the p e r i o d t o 1985 Numerical c o n t r o l l e d moving spot welders w i t h b u i l t i n c i r c u i t s f o r m o n i t o r i n g the q u a l i t y o f the spot welds have been produced Weld p a t t e r n s t o pre v e n t h e a t b u i l d up and d i s t o r t i o n should be evolved i n the next two years T h e r e f o r e I t I s b e l i e v e d t h a t the above man u f a c t u r i n g requirements w i l l be s t a t e o f the a r t b e f o r e 1985 A c r i t i c a l f e a t u r e o f r e s i s t a n c e spot welds i s t h e i r f a t i g u e c h a r a c t e r i s t i c s f o r long l i f e (30 000 hours p l u s ) a i r c r a f t such as the SST and o t h e r supersonic v e h i c l e s P r e l i m i n a r y t e s t data i n d i c a t e t h a t spot welds are f a i l i n g a t t o o low a c y c l e time a t s t r e s s l e v e l s o f approxi m a t e l y two t h i r d s o f v a l u e s deemed d e s i r a b l e and probably a t t a i n a b l e by o t h e r j o i n i n g processes Much work has gone i n t o s t u d y i n g the process and making r e f i n e m e n t s t o improve I t For g i n g Che weld s t r e s s r e l i e f and cryogenic t e n d e r i n g have a l l been examined w i t h p r o m i s i n g r e s u l t s For s k i n - s t r i n g e r combinations c l a s s AA welds produced by u s i n g a scab s t r i p have been c y c l e d over 10 000 times I n f a t i g u e I t i s expected chat s t r u c t u r e s engineers w i l l i n the ensuing years address themselves t o the development o f improved t e s t i n g methods and t h i s accompanied by c o n t i n u e d search f o r optimum r e s i s t a n c e w e l d i n g c o n d i t i o n s , w i l l e s t a b l i s h design parameters which w i l l s a t i s f y the que s t i o n s concerning f a t i g u e w i t h o u t recourse t o a c c e l e r a t e d development programs ALTERNATE PROCESSES NONE Code
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S . A N D A A R P R A T I N G F A C T O R S I CAMR CHMCr I y g g I _V£3 BBP B-30e, 4 U Gootponent 01 01 1 ABROCVHAHIC LIFT h COOTROL STRUCTURE - RIGID SKIN f o i A-3a hypcraonlc c ru i s e h i g h a l t i t u d e or low a l t i t u d e v e h i c l e s and f o r A-3b hypersonic boost g l i d e s t r a t e g i c or t a c c i c a l v e h i c l e s NOSE f o r A-3c hyper-REF B-52b Component 01 03 0 sonic H T O L ' o r b l t a l v e h i c l e REP B-13 124 Component 07 02 0 ELECTROMAGNETIC TRANSPARENCIES (RADOMES RADAR WINDOWS) f o r A-2 supersonic h igh a l t i t u d e long range a i r c r a f t and B-3a l i f t r e - e n t r y v e h i c l e s REF B-12 125 Component 07 03 0 OPTICAL TRANS- PAREtCIES (VISIBLE. IR UV) f o r A-2 supersonic a i r c r a f t and B-3a l i f t e n t r y v e h i c l e s REP B-14 Component 08 01 0 HEAT SHIELD f o r A-2 flupersonic a i r c r a f t as above REF B-92 97 Components 02 06 0 THRUST STRUCTURE ond 02 07 0 INTERSTAGE AND IKTERTANK STRUCTURE f o r B - l b ( l ) space launch Bystema e a r t h o r b i t launch and B-lbC2) space launch systems - lunar launch REF B 85d Component 01 02 0 AERODYNAMIC LIFT & CONTROL STRUCTURE FLEXIBLE f o r B - l a ( l ) and B U ( 2 } earch launch systems - recoverable booster and s ing le s t a g e - t o - o r b l t recoverable booster REF B-I08b Component 02 02 0 SPACECRAFT lOTERNAL STRUCTURE f o r B - 2 a ( l ) B-2a(2) B-2a(3) near space opera t ions spacecraf t - e a r t h s a t e l l i t e space s t a t i o n lunar v e h i c l e and f o r B-2c spacecra f t s h u t t l e (maneuverable) REF B95a Component 02 04 0 PRESSURE VESSEL f o r B - l b ( l ) and B - l b ( 2 ) space launch systems - ea r th o r b i t launch and lunar launch REP B W Component 02 07 0 INTERSTAGE AND INTER- TANK S.TRJCTURE f o r B - l a ( l ) and B - l a ( 2 ) e a r t h launch systems as above REF B96 Component 02 08 0 MAJOR FITTINGS (BULKHEAD ENGINE MOUNT) f o r B - l b ( l ) and B l b ( 2 ) space launch systems as above REP B-112a b c Component 07 02 0 ELECTROMAGNETIC TRANSPARENCIES (RADOMES, RADAR WINDOWS) f o r B 2 a ( l ) B-2a(2) B-2a(3) near space opera t ions spacecrafc and B-2c spacecraf t s h u t t l e as above REF B 98c Component 08 01 0/08 04 0 HEAT SHIELD/ EROSION-CORROSION SHIELD f o r B - l b ( l ) and B - l b ( 2 ) space lounch systems as above REF B 3 Component 01 01 1 AERODYNAMIC LIFT & COOTROL STRUCTURE f o r A 1 subsonic long endurance a i r c r a f t REF B-50a Component 08 01 0 HEAT SHIELD f o r A-3c hypersonic HTOL-orb l te l v e h i c l e SYSTtM PROBABILin ooM«ONa«r CRtriCAUTV FREQUENCY OF WMT IN SYCTCWt DESIGN ALTERMA'C MATCRIAIS IMmCATtm AARP RAW SCORCS n. 6 1* & 11 S 6 S 17. 8 "2 1 / ^ & 3 6 £ t> 3S .ouoi.l ?â¢. n. / C 0 29 01,0^0^ .Ape , H- 9 / 6 0 xt. 1% e 3- 6 6 0 39 ,*7, <>«{<> ,5 .3A 9 6 1. t 6 0 te fiXo.^t . It- Z C C 0 3Z e 9 â¢a. 6 6 0 31 ,<»*.?<« , , 9 ^. 6 0 3S ,«.2,<?<<> M<i.fiJ \ <f «. & Â¥ 0 3S t 9 «⢠(, Â¥ 0 33 n. (, 2 Â¥ 0 30 et.ono 6 z & Â¥ 0 ?o $ 12 z 9 6 0 37 Â¥ It 2 9 6 e> 33 n. C Z 6 i i> 32 / * & 9 6 i 0 3Z i 7. * ( 0 2Â¥ » 6 1 6 0 Z8 otrf-f fir/It & 9 t- 9 6 0 38 9 2 9 t 0 3e PttK7A ,8rfA('J e 3 Z 9 6 t> 2S .<a^7,o s./fi.ft} Â¥ 3 z f t t> 21^ / z C 1 6 6 t> 32 Â¥ % i 6 t> 2Â¥ ,e7e«« ,8-2^(1 It- 6 % « t 0 32 IV C 2 i 6 0 32 Â¥ C 2 i t <> 2f filAlU .B:3,e 8 6 3 t C <!> 2B It 9 Z. t 6 0 35- ce.e/e ,8 ( i f i j Â¥ 9 2. 6 i> 27 .01,91.1. ./i-/. . 8 e » c 6 0 i e It. Z 6 0 30 1
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S I CAMR CHAOr NUHBCR *foB REF B-30d A i d Component 01 01 1 AERODVNAHIC LIFT & COIrtROL STRUCTURE - RIGID SKIN f o r A 3a hypersonLc c r u U c h i g h a l t i t u d e or low a l t i t u d e v e h i c l e and A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e REF B-28c 39c Component 01 03 0 NOSE f o r A 3a and A 3b hypersonic veh i c l e s as above REF B-29b Component 01 04 0 LEADING EDGE f o r A-3a hypersonic c ru i s e v e h i c l e aa above REF B - l Z l c 133b Component 08 01 0 HEAT SHIELD f o r B-3a l i f t r e - e n t r y v e h i c l e s and B 3b drag en t ry v e h i c l e s REF B-62a b Component 01 04 0 LEADING EDGE f o r A 4 a ( l ) t a c t i c a l ground launched a n t i - m i s s i l e "Ebls CAKR Chart p e r t a i n s to new m a t e r i a l s which AAEtP d i d not consider In i t s ana lys i s of components, but f o r which wide usage la foreseen I n the 1970-1985 pe r iod One a p p l i c a t i o n Is c i t e d as an exanjple REF B-31d Component 01 01 2 AEROOYNAHIC LIFT & CONTROL STRUCTURE - RIGID SUBSTRUCTURE f o r A 3a hypersonic c ru i s e h i g h a l t i t u d e or low a l t i t u d e c r u i n e v e h i c l e REP B-133a b Component 07 02 0 ELECTROMAGNETIC TRANSPARENCIES (RADOMES RADAR WINDOWS) f o r B-3b drag en t ry v e h i c l e s REF B 133a Component 08 01 0 HEAT SHIELD f o r B 3b drag e n t r y v e h i c l e s REF B-137a b c Component 08 02 0 THERMAL INSULATION f o t B 3b drag en t ry v e h i c l e s KEF H l I R i e x p o n e n t HQ 02 0 SEAL f o r B 3b drag en t ry vch ic Ics REt B 52b Component 01 03 0 NOSE f o r A 3c hypersonic tITOL o r b l c a l v e h i c l e REF B 51c Component 01 04 0 LEADING EDGE f o r A 3c hypersonic KTOL o r b i t a l v e h i c l e REF P ropu l s i on Requirements J o i n i n g No 2 Component 10 07 0 TURBOJET AFTERBURNER FLAPS f o r A-2a supersonic h i g h a l t i t u d e long range chemica l ly fue l ed a i r c r a f t f o r A-2c supersonic t a c t i c a l V/STOL f i g h t e r and fo r B-Va ea r th launch syacem recoverable booster Components 13 02 0 RAHJET DIFFUSER SKIN and 13 03 0 RAMJET COMBUSTION CHAMBER f o r A-3a hypersonic c ru i s e h igh a l t i t u d e v e h i c l e and B- la e a r t h launch system recoverable booster Component 14 02 0 LIQUID ROCKET NOZZLE f o r B- la ea r th launch system - recoverable booster fo r B - lb space launch system f o r B 2a(2) near space opera t ions spacecra f t - space s t a t i o n and f o r B-2c spacecra f t s h u t t l e Components 16 03 0 SOLID ROCKET NOZZLE and 16 07 0 SOLID ROCKET GUIDE VANES f o r A-4b s t r a t e g i c m i s s i l e s and B- l a c o r t h launch system - recoverable booster k k SYSTEM PROBABILin OOMnMENr CRtTicAirrr FRESUCNCY OF l a v i t IN SYSTEK\ PESIGN ALTERNA><3 MATCRKUS IMPUCATION AARP RAW SCORES I t 8 ft a.'K b% 3 1 1 1 &3 £ 4-0 e fZ 2 c e i> 3¥ .01 el J^ . /<3t/^ , ¥ / 2 1 . i 0 2 7 oleie , ^ 9 * , e <? 2 & c 0 SI ?5? .^H. ¥ 9 2 3 c 0 2¥ filM9 8 /Z Z e, 0 3¥ fi.e,ql,e, ,$�<>.. e /Z / C 0 3o .0.6.91.0 .836. /2 /* / 3 0 3¥ .o./Me. AM) £ f 6 i> X /Hr tpeuTtriiP ft. <f / 3 0 3/ 6 1 3 0 /z 6 2. 9 0 33 /* fz. 2. 9 ¥ 0 39 9 / & 0 3¥ 3 / 3 0 Z3 1 6 & 0 2 7 fi.i^^H". . 9 z i 6 i> 2 7 je.0%0 . / ) ^ , /z i 1 6 & * 3/ 6 f 6 0 3( fo o7o 3 ( A 6 3 Z l> Z<i , t% ote / ' 3a , 9 « i> 31 ,/3,i>tJ> ,<f / a . e 9 3 i> 3Z /S.oJB , /»3«, B 9 2 c i> 31 Ito'to , SVrt. e 9 3 i, * 3Z /4oto Sh . 8 9 3 3 c 0 29 /f.'.i.'. .S/$. (Z 9 % 3 6 0 32 n. ( / 3 C 0 26 B 9 1 3 i> 37 ,(6 03.0 Z 3 6 « 3Z Continued on next page
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S I <MMR CHAftr HIIHOta, Â¥/3 M>4 tie Continued f r o o p ieced lng page REF B-169a Componenc 05 03 0 SURFACE CONTACT DBVICB fox C-2b o x p l o i a t o r y Crsveraet ( l u n a r ) REF B-160b Component 03 07 0 EXHAUST DEFLECTION STRUCTURE f o r C- la e a r t h base launch pad REF B-161 Component 08 02 0 THERMAL INSULATION f o r C - l b ea r th baae v e h i c l e c o n d i t i o n i n g equipment REF B-3, 69 Component 01 01 1 ABRODVNAMIC LIFT & CONTROL STRUCTURE - RIGID SKIN fox A-1 subaonlc long endurance a i r c r a f t and A-3c hyperaonlc HTOL-orb l t a l v e h i c l e HBP B-95 Component 02 06 0 PRESSURE VESSEL f o r 8 - l t > ( l ) and B - l b ( 2 } apace launch systems - e a r t h o r b i t launch and lunar launch REF B-92 Component 02 06 0 THRUST STRUCTURE f o r B - l b ( l ) and B - l b ( 2 ) as above REF B-97a c Component 02 07 0 INTERSTAGE AND INTERTANK STRUCTURE f o r B l b ( l ) and B - l b ( 2 ) as above REF B-96 Component 02 08 0 HAJOR FITTINGS - BULKHEAD f o r B - l b ( l ) and B - l b ( 2 ) as above REF B-98s b c Componenta 08 01 0/08 06 0 HEAT SHIBLD/EROSION-CORROSION SHIELD f o r B - l b ( l ) and B - l b ( 2 ) aa above KEF 8-99 Cooponcnc 08 02 0 THERMAL INSULATION f o i B ] b ( l ) and B l b ( 2 ) oA above REF B-169b Component 05 03 0 SURFACE CONTROL DEVICE f o r C-2b e x p l o r a t o r y t r averse r ( l u n a r ) REF fl-172b Component 08 06 0 PRESSURE SUIT f o r C-3a ex t ra -veh lcu la r /advanced space a u l t REF B-30a 61a Component 01 01 1 ABRODifNAMIC LIFT & CONTROL STRUCTURE - RIGID SKIN f o r A-3a hypersonic c ru i s e h igh a l t i t u d e or low a l t i t u d e v e h i c l e and A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e REF B-28c d Componont 01 03 0 NOSE f o r A-3a hypersonic c ru i s e h igh a l t i t u d e or low a l t i t u d e v e h i c l e REF B-29b c d 51b Component 01 04 0 LEADING EDGE f o r A 3a v e h i c l e as above and A-3c hypersonic HTOL- o r h t t a l v e h i c l e 'Z. SYSTEM PROBABILin COMPONEHT' CRITICAUTY' FRESUCNCY or l a w t IN SVSTEÂ»Ì DESIGN ALTERNAra MATCRimS IMPU CATION AARP RAW It e <* It << 6 3 3 1 I 1 & 3 6 4-0 T * T A L S 8 3 6 i> 33. f t & 2- 6 C 0 32 It."70, .et/.»^ , 3 6 & i> 29 ,o,Se;ifi, ,0:ib Â¥ 6 / 3 o 0 / Â¥ .eSfO/Jo, ,C, la. , & / 3 o 0 3Z ,oeeio ,<"/*, e / 6 & C- 31 e/ 911 A'l. . 6 1 6 0 J 7 _ 0 3 3 0 3, i> 36 01.011. 6 / ,t>7(></6 ,B,/,b() f t . 9 3 9 ,07,1)1/0 0,l,bj^) 9 9 _6 & fiLeto fil.b.lfj n 9 3 02010, ^ Ibfy 1 * 9 3 6 .OZeto ,5 (1)0) n 6 3 <g 6 ,e>t.o7,o ,gl,6fi/ 3 9 a 23 OtltiP ,S, (bO) It 3 9 0 3i fifoS,e, jSrl^^ V ( 3 9 & 0 28 fi.S.oi.o, .Si-/Mj l i 9 <? C t 3f .o.e. p(x> /,b,fy u 9 J 9 (> 31 ot.otci S.l.b6Jl f t fZ 3 6 0 f t ,oB. I??-* Ib/ii /2 3 6 t> 3*1 eS.oiq ,C'2J> & / 6 0 2 3 oe,o6e> ,C3a. 9 / 6 O 0 2 0 ol ol 1 A 3i(. e / 2 â¢a 3 6 0 32 ,»'.'?'! 1 /Z. 1 3 & <> 26 8 9 3 3 (. I) 29 e> _ 3 _ 6 * 32
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S I CAM A CHARr Concinued from piecedlng page REF fl 32o Cotnponent 06 01 0 AIR INLET & DUCTING f o r A-3a hypersonic c r u i s e v e h i c l e as above REF B 6 Component 06 03 0 VECTOR COHTROL & THRUST DEFLECTOR f o r A - 1 subsonic long endurance a i r c r a f t RBF B-50a Component 08 01 0 HEAT SHULD f o r A 3c hyperaonic HTOL-orb l t a l v e h i c l e REF B-17i Component 08 07 0 RE ENTRY ENCLOSURE (INDIVIDUAL) f o r C-3c a b o r t / m l a s t o n r e - e n t r y enclosure REF P ropu l s ion Requirements J o i n i n g No 9 11 Componenca 18 05 0 GASEOUS FLIGHT POWER HEAT EXCHANGER and 18 06 0 GASEOUS FLIGHT POWER DXTINC- PIPING f o r A - l b subsonic long endurance nuclear a i r c r a f t f o r A 2a supersonic high a l t i t u d e long range c h c n l c a l l y f u e l e d and A-2b nuclear powered a i r c r a f t f o r A-3o hypersonic c r u i s e h igh a l t i t u d e or low o l L l t u d e v e h i c l e s f o r A 3c hypersonic HTOL o r b i t a l v e h i c l e f o r A-4b(3) s t r a t e g i c space launched ICBH f o r B la e a r t h launch systcins f o r B lb space launch systems fo r B-2a(2) near space opera t ions space s t a t i o n and B 3a(2) l i f t re en t ry v e h i c l e lunar r e t u r n REF P ropu l s ion Requirement No 10 11 Component 21 01 0 THERMOELECTRIC THERMIONIC DUCT INC-PIPI^G f o r B la e a r t h launch system recoverable booster B l b bpacG launch aystem B-2a(2) near space op(.raclonn space s t a t i o n ond B 2c spacec ra f t s h u t t l e Components 22 03 0 CLOSED CYCLfc TURBOELECTRIC HEAT EXCHANGER and 22 05 0 DUCTING PIPING f o r B IbCl) space launch system B-2a(2) apace s t a t i o n B-2a(3) lunar v e h i c l e and B-2c spocccrofc s h u t t l e k k 3YSTEM FMBABILHY COMPOKEHT CRITICAUTr FREQUCNCV OF MVlT rN SYSTEM D£5IGN ALTERNA.i3 MATCRIAIS IMFUCATUW A A R P C A W scoecs 11 8 4 12. 1 6 3 3 1 1 S 3 T * T A I . 9 3 3 c i> zs .O.i.e.iA A?'^, 0 9 3 3 0 i9 8 » 3 6 0 M n. 3 3 6 0 Z? ee.oZ". , , 6 9 1 3 6 0 3f , / ,«.«?â¢( 0, A 't>. . f 6 3. 3 0 / / «⢠3 JAlKo. ,/??^, 6 » 3 0 8 6 3 3 0 zc « f 3 3 i i> z r e c Z 3 c a ar ./e o^o ,a/a., s 1 3 3 0 Z f 9 3 3 t 0 33 9 3 3 C 0 33 Â¥ f 2 3 i 0 2V , y 6 « u 0 2 / 0 2» 0 2 / f t 9 3 b 8 (, 1 3 ./8c*.o. ,A-U. i "3 3 C i> t6 .t8.et.A A'$P. f 3 3 i 0 *s- ft.oi-P. AfiTs) s 6 X 3 c 0 2S 8 9 3 3 6 C Z9 .a a,. / t 9 3 3 0 33 /«. 9 3 3 c 6 33 9 2 t 0 3-V .VPA". ,s;/,ef. e 9 ? 3 (. 0 T9 /a- 9 3 3 f. 0 33 , n 9 3 t 3 c i> 33 Z/,0/,0, .S.'U. e 9 Z e. 0 »S Z2A3.0. S<if6i fZ 9 3. 3 & 0 32 22 <>3o p Zefy /». 9 3 2. 3 6. 3J y 9 i * 2 y <t 7. 3 t 0 2? It. f 2 i c 0 7 2 f 3 S £> 33 _ 5 L _ 9 Z i 0 2V Z 3 0 0 <>
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S CAMR CHMtr NUHOCB. J i l l . REF B-3 30b c 41b c Component 01 01 1 AERODYNAMIC LIFT & CONTROL STRUCTURE - RIGID SKIN f o r A - 1 subsonic long endurance a i r c r a f t f o r A-3a hypersonic c r u i s e h i g h a l t i t u d e or low a l t i t u d e v e h i c l e s and f o r A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l veh i c l e s REF B-122b Component 01 01 1/08 01 0 AERODYNAMIC LIFT h CONTROL STRUCTURE - RIGID SKIN/HEAT SHIELD FOR B 3a l i f t r e - e n t r y v e h i c l e REF B-146 Component 01 02 2 AERODYNAMIC LIFT & CONTROL STRUCTURE - FLEXIBLE (SHROUD LINES) f o r B-4a e a r t h l and ing systems REF B-11 51a b Component 01 04 0 LEADING EDGE f o r A 2 supersonic h igh a l t i t u d e long endurance a i r c r a f t and t o c t l c a l V/STOL f i g h t e r a i r c r a f t f o r A-3c hypersonic HTOL-orb l t a l v e h i c l e REF B-107d Component 02 01 0 SPACECRAFT HULL f o r B - 2 a ( l ) B 2a(2) B-2o(3) near space opero t lona ea r th s a t e l l i t e space a t a t l o n lunar v e h i c l e j f o r B-2c spacec ra f t s h u t t l e ind REF B 147 Component 05 03 0 SURFACE CONTACT DEVICE f o r B-4a e a r t h landing systems REF B 4 Component 06 03 0 VECTOR CONTROL & THRUST DEFLECTOR f o r A 1 subsonic long endurance a i r c r a f t REF B-50a Component 08 01 0 HEAT SHIELD f o r A 3c hypersonic HTOL-orb l t a l v e h i c l e REF Propu l s ion Requirement No 12 Components 13 01 0 RAKJET DIFFUSER LEADING EDGE and 13 02 0 RAHJET DIFFUSER SKIN f o r A-3a hypersonic c ru i s e high a l t i t u d e or low a l t i t u d e v e h i c l e f o r A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e f o r A 4a(3) t a c t i c a l m i s s i l e SRBM and f o r B- l a e a r t h launch system recoverable booster REF B 134a Components 01 01 l / O l 01 2 AERODYNAMIC LIFT & CONTROL STRUCTURE HIGID SKIN/RIGID SUBSTRUCTURE fo r B 3b drag entr> v e h i c l e s REF B 107d 108a 109b 111b Components 02 01 0 SPACECRAFT HULL 02 02 0 SPACECRAFT INTERNAL STRUCTURE 02 03 0 SPACECRAFT EXTERNAL STRUCTURE 06 05 0/07 01 0 SOLAR COLLECTOR STRUCTURE/ANTENNA f o r B - 2 f l ( l ) B-2aC2) B 2a(3) near space opera t ions e a r t h B o t e l l l t c space s t a t i o n lunar v e h i c l e and f o r B 2c opacccrof t ehucclc REF B-176 Component 06 04 0 HEAT EXCHANGER (RADIATOR) f o r C 4fl power genera t ion space support system REF B 172a Component 08 06 0 PRESSURE SUIT f o t C-3a e x t r a - v e h i c u l a r advanced space s u i t /> k S Y S T t M PROBABILin COMPONENT CRITICAUTV FREaUCNCV OF savtT IN SYSTEM DESIGN ALTERNATC MATERIALS IMniCATUW AARP RAW 3 c o t ; c s n e t It 1 6 S 8 1 \ S 6 3 6 4 - 0 TOTALS en.oi.i, A-(. , » 2. 6 6 .Olo/.l, ,43a, , n C 6 0 3¥ .ohoi.i. ,/?-?^, V n » i t) 30 OI.OI.J, e ft. / ( 0 33 .o.Uo,ZZ,S¥<!-. / z IZ X _3__ t 0 3S .o.l.o.<<e, , f i z . . n 9 1 c 6 0 3¥ tf/oVo ,/!3e^ 4 9 2 . 6 0 2 7 .O.iolp, ,s;^a.f) 1% IZ / 3 C 0 7^ .oto/^o, JB.Zfi/i} 12 IZ / 3 6 t> i f 0 ze ,e>,2,e/,e, ,8, 2a,(j, V 12. 1 9 ,0,7,0/e, ,S.p?. t IZ 1 3 0 30 ,os;t;3.o, ,s</o.. IZ £> X 3 0 Z9 ,e>(oto , , e 9 2 C 0 31 ,ee.ofti ,4^p^ ¥ IZ 2 f £ 0 3e 13.0,1.0 ,A3,a, , e IZ 2 3 0 31 It 010 ,A1b, y IZ 2 3 i 0 i f , 1,7 0/ 0 ^(4; IZ z. 3 6 i> y .13.0/.o ,S-lcf.. 8 /Z Z 3 C 0 38 IS.Ol'O. 8 9 Z 3 e /3.o^o. A ?¥. ¥ 9 z 3 c 0 t¥ , 13,07. t, fl.'fo.fj) 9 z 3 0 }>. .n.oi,o, ,B-/<f-. 8 9 z 3 c 0 28 A/,o/,i. n C> 1 3 t> 38 .O.Zfilo fi,3A,(o /Z IZ 3 3 6 t> 36 eZpfp^ ,S,^,(t) IS 3 3 6 t> 36 .el,C)l_o ,S,Zi(3) ¥ / « 3 C {> 28 ,OZ,p/q ,B.-2*r e IZ 3 3 A 0 32. 02,of,o, ,B^.6j fZ 6 3 3 6 0 So e>2,o,t.e /B,2fi,0y fZ i 3 3 6 0 3o .oi.tirt, ,g2^(^ 9 _^ 3 3 t 0 3Z .oZote ,^-2,e. n 6 3 3 6 £> 26 ei2,e>3c 3,i»0} ft 6 3 3 0 3o 02x>St.e ,a^fy It 6 J 3 C {> 3e e>?p,s.o. , 9 3 ( 0 22 .oM,4), ,B-iie 3 3 0 36 .e>e,o&e, Si^O) It 9 3 3 £ 0 3s iz 9 3 3 0 33 .3 3 <> 2S-
E X P L A N A T I O N O F C A M R R E F E R E N C E S TO S Y S T E M S . C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S I CAMR CHMtr NUMMK Continued f rom preceding page REF B-16a Component 01 01 1 AERODYNAMIC LIFT & CONTROL STRUCTURE - RIGID SKIN f o r A-2 superaonlc h i g h a l t i t u d e long range a i r c r a f t or t r a c c l c a l V/STOL f i g h t e r REF B-11 Component 01 06 0 LEADING EDGE f o r A-2 supersonic a i r c r a f t as above REF B-15a Component 06 01 0 AIR INLETS & DUCTING f o r A-2 superaonlc a i r c r a f t as above REF B-30d e 61e Componenc 01 01 1 AERODYNAMIC LIFT & CONTROL STRUCTURE - RIGID SKIN f o r A-3a hypersonic c ru i s e h igh a l t i t u d e or low a l t i t u d e v e h i c l e s and f o r A 3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l veh l c l ee REF B 31a Cotbponent 01 01 2 AERODYNAMIC LIFT & CONTROL STRUCTURE -RIGID SUBSTRUCTURE f o r A 3a hypersonic c r u i s e v e h i c l e s as above REF B-28c d 39c d Component 01 03 0 NOSE f o r A-3a and A-3b hypersonic veh i c l e s as above REF B 29a b c 60c d Component 01 06 0 LEADING E X E f o r A 3a and A-3b hypersonic veh i c l e s as above REF B-133a b c Component 08 01 0 HEAT SHIELD fo r B-3b drag en t ry veh i c l e s REF B95a Component 02 06 0 PRESSURE VESSEL f o r B - lb space launch syaceniB REF B 86 Component 02 07 0 INTERSTAGE & INTERTANK STRUCTURE f o r B la ea r th launch systems REF B-96 Conponenta 02 08 0 HAJOR FITTINGS (BUUOtEAD} For B l b spac* launch syateati REF B-98c Componenta 08 01 0/08 06 0 HEAT SHIELD/ EROSlON-CORROSION SHIELD f o r B l b space launch systems REF B-30b c 6Ic Component 01 01 1 AERODYNAMIC LIFT & CONTROL STRXTURE - RIGID SKIN f o r A 3a hypersonic c ru i s e h igh a l t i t u d e or low a l t i t u d e v e h i c l e s and A 3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e REF B I22b c Componenta 01 01 1/08 01 0 AERODYNAMIC LIFT & CONTROL STRUCTURE - RIGID SUBSTRUCTURE/HEAT SHIELD f o r B 3a l i f t r e - e n t r y v o h l c l e a REF B 136b Componenta 01 01 1/01 01 2 AERODYNAMIC LIFT h CONTROL STRUCTURE - RIGID S K I H / R I G I D SUBSTRUCTURE f o r B-3b drag e n t r y v e h i c l e s REF B-31C 62b c Component 01 01 2 AERODVHAHIC LIFT & CONTROL STRUCTURE RIGID SUBSTRUCTURE f o r A 3a and A-3b hypersonic v e h i c l e s as above REF B 52o Component 01 03 0 NOSE f o r A 3c hyperaonlc HTOL-orb l ta l v e h i c l e REF B 5 lb Component 01 06 0 LEADING EDGE fo r A-3c hypersonic I lTOL-orblcaI v e h i c l e REF B-I8c Component 01 08 0 MAJOR FITTINGS (BULK- HEAD WING HINGE ENGINE MOUNT) f o r A 2a supersonic h igh a l t i t u d e long range a i r c r a f t REF fl-15a Component 06 01 0 A I R INLETS & DUCTING f o r A 2a and A-2b supersonic h igh a l t i t u d e long range s l r c r a f C chemica l ly f u e l e d or nuclear powered REF B-50b 133d e Component 08 01 0 HEAT SHIELD fo r A-3c hypersonic HTOL o r b i t a l v e h i c l e and B-3b drag encry v e h i c l e s el,030 ,e>,l,e,<lo ."Ml,". ,et, pyp fiS-ole, 0A?<< ."l.oj.l ,01 el,I, 01,01,1, el Pi t , el CI» .01,03 p ol,oyo ,oi,oeo Oiofe eC-elp, eg, 010, eB ol o k SYSTEM PROBABlun COMPONEKT CRITICAUTr FKEQUUCY OF f a u t IN SVSTEM DESIGN ALTERNATQ MATCRIA13 IMFUCATVM AARP RAW SCORES » e 4 It 6 3 3 1 1 S & 3 T»TAL ff S 9 3 3 c l> Z9 .^â¢â¢'^, /2 <f / 3 c 0 ^1 ,C3eL , /Z 9 / 6 0 3/ /Z 9 3 C, t 0 S£, /» 9 3 £ i. 0 3£ 3 3 c C 0 3o l i S 3 £ 0 37 A3i , Â¥ IZ 2 3 0 27 8 6 3 3 C 0 Z4, A^t, $ ? 3 3 0 ^9 A ^ . Â¥ 9 Z 3 e 0 ZV It 3 3 ft 0 3Z Â¥ f 2 3 6 0 2Â¥ /z /* / S 0 3Â¥ / z ? 2 Â¥ 0 33 e 3 / Â¥ 0 2Z ;S'/b, /2- 2- </ i> 3o .8-/4>. /Z 9 e- 6 6 33 ,113a. 9 IZ 3 3 t> 3Z /13 b Â¥ IZ 3 3 t} Z& ,*.3f». S IZ 1 3 3o n. (, 2 6 0 3Z 6 3 3 i) 26 /I-36 Â¥ 9 S 3 6 , 3.f Â¥ 9 2 3 t> 2f Â¥ 9 2 3 0 z f - ,/>3L,b H 9 2 3 i> Z1- , A Ztt iz 3 1 t, t 0 ze A-ib Â¥ 3 Z £ 0 ^1 A ? f . Â¥ n Z 3 e. 0 Z7 /z IZ z 3 6. 0 3r e /2. 3 3 £ i> 3Z Continued on next page
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S . C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S CAMR ctmtcr NUMBCR Continued f rom preceding page REP P r o p u l s i o n Requirement No 12 Components 13 01 0 RAMJET DIFFUSER LEADING EDGE and 13 02 0 RAKJBT DIFFUSER SKIN f o r A-3a hypersonic c r u i s e h i g h a l t i t u d e or low a l t i t u d e v e h i c l e s A-4a(3) t a c t i c a l D i s s i l e - SRBM and B- l a ea r th launch system - recoverable booster REF B-30a c 41a c Component 01 01 1 AERODYNAMIC LIFT & CONTROL STRXTURE - RIGID SKIN f o r A-3a hypersonic c r u i s e h igh a l t i t u d e or low a l t i t u d e v e h i c l e s and A-3b hypersonic boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e s REF B-122a Components 01 01 0/08 01 0 AERODYNAMIC LIFT & CONTROL STRUCTURE - RIGID SKIN/HEAT SHIELD f o r B-3a l i f t r e - e n t r y v e h i c l e s REP B-31a c 42a c 123 Components 01 01 2 AERODYNAMIC LIFT & CONTROL STRXTURE - RIGID SUBSTRXTURE f o r A-3a, A-3b and B-3a v e h i c l e s as above REF B-28c d 39c d Component 01 03 0 NOSE f o r A-3a and A-3b v e h i c l e s as above REP B-29b c d 40c d 51b 120a c Component 01 04 0 LEADING EKE f o r A-3a A-3b B-3a v e h i c l e s as above and A-3c hypersonic HTOL-orb l to l v e h i c l e REF B-32a b Component 06 01 0 AIR INLETS & DUCTING f o r A-3a v e h i c l e s as above REF B-4 Cotnponenc 06 03 0 VECTOR CONTROL t, TliRUST DEFLECTOR f o r A 1 subsonic Ions endurance a i r c r a f t l E t B 110a h 176 Component 06 04 0 HEAT EXCHANGER (RADIATOR) f o r B - 2 a ( l ) B-2a(2) B-2f l (3) near space opera t ions - ea r th s a t e l l i t e space s t a t i o n lunar v e h i c l e f o r B-2c spacecra f t s h u t t l e end f o r C-4a power genera t ion space support system ElEF B 50a b 121o Cotnponenc HEAT SHIELD f o r A 3c hypersonic HTOL o r b i t a l v e h i c l e and B 3a l i f t r e - en t ry v e h i c l e REF B-174b Component 08 07 0 RE-ENTRY ENCLOSURE (INDIVIDUAL) f o r C 3c l i f e support abo r t /m la f i l on r e - e n t r y enclosure REF P ropu l s i on Requirement J o i n i n g No 9 Components 18 05 0 GASEOUS POWER HEAT EXCHANGER and 18 06 0 CASEOUS POWER DUCTING-PIPING f o r A - l b subsonic long enduronce nuclear powered a i r c r a f t A-2o and A 2b Gupeisonlc h igh a l t i t u d e long range chemical or nuclear powered a i r c r a f t A 3a hypersonic c ru i s e and A 3c HTOL-orb l t a l v e h i c l e s as above A-4b(3) s t r a t e g i c m i s s i l e - space launched ICBM f o r B l a e a r t h launch syatema - recoverable booster B- lb space launch systems B-2a(2) space s t a t i o n and B-3a(2) l i f t r e - e n t r y v e h i c l e lunar r e t u r n Continued on next page DPI9. A3A SYSTem PROSABIUT^ COMHONENI O U T I C A U T Y FREBUCNCV or m\*T IN s m E > A DESIGN ALTERNA'i: MATERIALS ! IMPUCATKA AARP RAW scoecs n e <> 11 1 6 S 8 1 1 6 4 - 0 TOTALS 12. 3 s i> 28 jsp,4> . A9pfi n z 3 0 K .13,0/p. .3.1*; B 12 2. 3 £ i) 31 . /? ,«>,2,« , , ^Sa. a 9 3 3 6 0 29 ,/3.e>Ze! ,/0-3i Â¥ 9 3 3 & 0 2S- .lt,<>.2.-o. A<Hx Mtr 9 Z 3 6 0 X , / ; » , « . 0 , , 8 9 t 3 0 2 * .'l-,ol.'. y ? - . e / 2 3 e. y 0 3 3 . / « ? « . / z 3 Â¥ 0 Z'\ 8 It Z V 0 3Z 8 i 3 & V 0 a7 OlelZ A3l . . . . 1 1 ⢠⢠1 y 9 3 6 y 0 2 6 O.'.'f^. , ? 1 ^ . 8 A 2 6 V 0 2i 01 03-0 , A 3fl . . . . 1 . . 1 . 6 9 3 3 Â¥ 9 1 3 Â¥ 0 23 12 â¢J 3 Â¥ 0 3o .olM.o, A3k. Â¥ f 3 3 Â¥ 0 23 el_ȴo ,/> 3c, Â¥ 1 3 y 0 2Z el. ? A , g 9 2 3 y 0 26 eteLo A-3*. 8 9 a c V C So 8 9 1 i. H- [> 26 fi^eilo, ,8,2>(iJ n IX 1 3 Â¥ ⢠C> 32 n 12 s 3 t> 39 Â¥ 12 2 3 0 2 r C>io<fe ,J| 2e 8 12 S 3 ^ 1^ 3e .oeo,Â¥.e C Â¥A / 2 9 ) 3 6 2S ,0601,0 ,^3<!, Â¥ 12 2 <f 0 2S eiole ,SSa., 8 It 2 3 V- 0 2 9 08 o7e C 3c 8 9 / 3 <f i> » r .A.IIf. H C Z 3 << ' 9 ./e.oSp .A-2A, 12 6 4 . 3 4 27 ,A2k. i 2 3 0 ;7 of* i 3 i> 2if Ig os o ,A3f, 9 2 0 « l ,f,t.o^o ,4Yii) S 6 2 0 23 .It.0.^.0. .^<»t 8 <» 2 4 . 0 it. ys.ero ei^ >l <J 3 i> 3\ ,/8.<^.i>, ,e3flCi) 11 <1 3 - L i> 31
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S CAMR CHAUr NUHBCR Continued f rom preceding page REt P r o p u l s i o n Requirements J o i n i n g "flo 10 Component 21 0 ' 0 THERMOELECTRIC-THERMIONIC DUCTING-PIPING f o r 3 - l a B - l b B-2a and B 2c systems as above romoonents 22 03 0 CLOSED CYCLE TURBOELECTRIC HEAT FXCHANGERS 22 05 00 DUCTING-PIP INC and 22 06 0 TIRBINE CASING f o r fl-lb B-2a and B-2c aystoms as abovt REh R 30d i l d Component 01 01 0 AERODYNAMIC LIFT fx CONTROL STRUCTLTIE RIGID SKIN f o r A-3a hypersonic c r u i s e hl( ,h a l t l t u d t . or low a l t i t u d e v e h i c l e and A 3b hypi-rsonlc boost g l i d e s t r a t e g i c or t a c t i c a l v e h i c l e KEF B 28c Component 01 03 0 NOSE f o r A-3a veh i c l e s as above REF B 29b 120a c Component 01 OA 0 LEIADING EDGE f o r A-3a v e h i c l e s as above and B 3a l i f t r e - e n t r y v i , h i c l c s REF B-4 Component 06 03 0 VECTOR CONTROL & THRUST DEFLECTOR f o r A-1 subsonic long endurance a i r c r a f t REF B-12la c Component 08 01 0 HEAT SHIELD f o r B 3a l i f t r e - e n t r y v e h i c l e s REt B-138a Component 09 02 0 SEAL f o r B-3b drag en t ry v e h i c l e s REF P ropu l s ion Requirement J o i n i n g No 2 Component 10 07 C TURBOJET AFTERBURNER FLAPS f o r A 2a super- â¢ionlc h igh a l t i t u d e long range chemica l ly f u e l e d a i r c r a f t f o r A-2c supersonic t a c t i c a l V/STOL f i g h t e r and f o r B- l a e a r t h launch system recover able booster Components 13 02 0 RAMJET DIFFUSER SKI and 13 03 0 RAMJET COMBUSTION CHAMBER f o r Continued on next par,e ll k S Y S T E M FROBABII.in' CDMroNENr CKCTICAUTY FREQUUCY or sawt IN SYSTEM PESIGN ALTERNA £3 MATCRKUS iMrucAnoN AARP RAW S C O R C 3 11 <) 6 3 3 1 1 6 4 - 0 9 z 3 JtJ>.i.o. A. il>. . 4 6 a. 3 0 /9 ,A.Jit^ , 13. i a. 3 *k 0 2 7 V i. a. 3 i> 19 e t 3 3 0 zy f 9 â¢z 3 y d> Z6 8__ 8 i a. 3 ./.e.eti.o, ,9<a, , 9 2 3 n 9 8 3 Â¥ 0 3 1 3 3 0 31 y 9 Z 3 y 0 2 Z .V.o.lp, ,8/e, . 8 f z 3 y 0 26 Z lP l f i , .8/1,, IZ 9 3 3 y 0 sr / 2 9 3 3 y 1> SI l/.c/e, & 9 3 3 y /2 <} 3 3 y â¢l7.t>3o ,C(2«,lij /2. 9 3 3 y 0 31 ,2?oJo , 5 2,Ì 3) 9 2 3 i> 2 2 6 9 3 3 1? 37 f^M". AMk / 2 f 3 3 y 0 I ' /a 9 3 3 y 0 31 y 9 Z 3 y M o r e , S,Z<? 8 9 3 3 y 0 ^7 n 3 <f /« i 3 3 y t Z 3 y 0 '<) IZ.OCB , ? 2 f 8 i 3 3 y 01,9'.'. , ^ ? « - . 8 12. 3 3 0 3 Z »' ? " . . It. 1 3 £ 0 26 8 9 3 3 C * 29 ol,o9.o , A 3 » , 8 / 2 3 3 & t> 32 ,e>/,oye .a,?©, e <> Z 3 t, 0 2g 0(03 0 e 9 1 3 t. * i7 s tz Z 3 0 31 e>9p7c S^^t tz 3 / 3 6 0 zt jo,<n,o_ A?f^. 12 6 ( 6 6 0 31 tz 6 I & C 0 3«f 10 O7JB 8 /a _ . _ t _ l _ L j I . 1 1 , 8 i 3 6. i> 2<i
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S . A N D A A R P R A T I N G F A C T O R S I CAMR CHART NUMBCR I Â¥04 4V]_ Conclnuad f rom preceding page A-3a hyperoonlc c r u i s e h i g h a l t i t u d e v e h i c l e and B- l a e a r t h launch system - recoverable booster Component W 02 0 LIQUID ROCKET NOZZLS f o r B - l a ea r th launch system, f o r B - l b apace launch system f o r B-2a(2) near space opera t ions spacec ra f t - space s t a t i o n and f o r B-2c spacecra f t s h u t t l e Components 16 03 0 SOLID ROCKET NOZZLE and 16 07 0 SOLID ROCKET GUIDE VANES f o r A-^b s t r a t e g i c m i s s i l e s and B - l a e a r t h launch system - recoverable booster REF P ropu l s ion Requirement J o i n i n g Ho 4 Component 13 08 0 RAHJET FUEL SYSTEM THERMAL INSUUTION f o r A-3a hypersonic c r u i s e v e h i c l e s as above A-4b s t r a t e g i c m i s s i l e s snd B - l s e a r t h launch systems- recoverable booster REF P ropu l s ion Requirement J o i n i n g No 6 Component 21 03 0 THERMIONIC POWER SYSTEM CATHODE f o r B- l a e a r t h launch system B - l b space Isunch system B-2s near space opera t ions spacec ra f t and B-2c spacecra f t s h u t t l e REF P ropu l s i on Requirement J o i n i n g No 7 Component 21 02 0 THERMOELECTRIC POWER SYSTEM ELfiHBlfrS f o r A-2b supersonic h i g h a l t i t u d e long range a i r c r a f t f o r A-3a hypersonic c r u i s e h igh a l t i t u d e or low a l t i t u d e v e h i c l e s f o r A-3c hypersonic HTOL-orb l t a l v e h i c l e s , f o r A-4b s t r a t e g i c m i s s i l e s f o r B- l a e a r t h launch systems f o r B- lb space Isunch systems f o r B-2a near space opera t ions sp scec ra f t and B-2c spacecra f t s h u t t l e REF B-13ia Components 01 01 1/01 01 2 AERODYNAMIC LIFT f» CONTROL STRUCTURE RIGID SKIN/RIGID STRUCTURE f o r B-3b drag e n t r y v e h i c l e s REF B 107d 108a 109b 111b Components 02 01 0 SPACECRAFT HULL 02 02 0 SPACECRAFT INTERNAL STRUCTURE 02 03 0 SPACECRAFT EXTERNAL STRUCTURE 06 05 0/ 07 01 0 SOLAR COLLECTOR STRUCTORE/ANTENNA f o r B-2a near space opera t ions spacecra f t and B-2c spacecra f t s h u t t l e REF B-97b Components 02 07 0 INTERSTAGE & INTER- TANK STRUCTURE f o r B l b space launch systems REF B-168b 153a b Component 05 02 0 ENERGY ABSORBER f o r B-4a ea r th landing system and B-4b spaee landing system REF B-176 Component 06 04 0 HEAT EXCHANGER (RADIATOR) f o r C-4a space power genera t ion support systems Continued on next page ll k .l$.AiA ,4 3 4 , SYSTEM PROBABlun O0MI>0NEMr OlITICAUTr FREaUCMCY Of WtAt IN SYSTEM PES ION ALTERMA<<; MATCRIAIS IMrUCATIOI AARP RAW tt. e â¢* It <) 6 S S 1 1 l - b 3 6 4-0 e y 3 6 i> 32 .t3.<>%t( M-Ho, . 8 y 3 0 3 2 8 9 3 « t 0 32 ,/3o3o . ?./* 8 9 3 6 c 0 32 ./ff.oze, S-ftL , 8 3^ 3 6 1Ì 2<l MfiX". ,8tl>. / * 9 z 3 6 0 5Z MotA J8Zp,fl /Z 6 2 3 C 29 9 9 Z 3 0 *7 /a. 9 3 i * 36 8 9 % 0 J z A.-Â¥^. C 3 0 S3 ,/<.*â¢?», ,8-/A , 8 6 3 0 29 ,/3Ae^t>. A^, 8 9 3 t 0 3Z ./3,*6e ^ y ^ , n 9 3 <> 36 /B.f^ B / t . 8 ? 3 0 32 2/030, ,8/.o,. 8 9 3 i & 0 32 ,91^3.0. ,^-fJ>. /2 9 Z 6, 0 ss- .2/,o3o .8?e. tz 9 Z C (. 0 Js- ,3/03, 0 ^ a-aa. 8 1 2 t c t> 31 9 2 c c 0 zi ,2leZC ,A3a. 8 9 3 c 6 0 32 ,Z/.ol,o, ,^3f. y 9 / 6 i 0 3i .Zlp,t:'> tz 9 3 0 36 , a r / » , 8 9 % 6 L 0 3 Z It 9 Z 6 i> 3S It 9 i 6 6 0 3s- 7,l,q2o ,BiZf>, 8 9 Z 6 t> 31 01 AU, ,B:il>. It C Z 3 6 0 »9 f t tz 3 3 6 t> 36 ,03,01,0. ,nze. 8 12 3 3 & 0 3 2 12 C 3 3 t) 3C e c 3 3 & 0 26 It 6 3 3 e t) 30 O.to3e ,f,2,e. 8 C 3 3 c d 2C oZeffi. , 8 / p . 12 6 / 3 t 0 28 ,os.<ao ,B <(.»., It 9 / 3 6 t) 31 It 9 1 3 0 3/ .M.ttlfq ,<^,yfl; 12 9 -Jâ C 0 34
CAHR MMCT NUMIMA E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S ¥»f Â¥93 Contlnufld froa pracodlng pase Wl B -Ma Cospousnc 08 01 0 lOAT SHIBU) for A - ] c hyparsonic HTOL-orbltal v e h l c l a BH7 B-172al Caaq>oiiant 08 Ot 0 P U S S U U SUIT fo i C-3a extEa-vehicular/advancad apaca auLt U f a eupport aystama BBF B-13eb Componanc 09 02 0 SEAL for B-]b drag entry vahLclae BEF B-107a,d,e 108a,c, 109b, l l l a , b i Coiq>oiunta 02 01 0 SPACBCBATT HULL, 02 02 0 S F A d C B A n IHISBHAL STBUCTUBII, 02 03 0 SFACECBAPT BXTIIUML 8TRUCTUBE, 06 05 0/07 01 0 SOLAB COLLECTOR STRUCTURE/ANIEHNA (or B-2a naar apace operatlona apacocraft and B-2c apacecraft ahuttla BEr B-65b 69b 71bt Ccoponant 02 OS 0 SOLID BOCKBT MOTOB CASE tor A - « a ( l ) t a c t i c a l ground launched a n t l - o l a a l l o A-4a(2) t a c t i c a l apace launchea a n t l - n l a a l l e A-4b( l ) atrataglc mlas l lo - raoblle IceM, A-4o(2) actaceglc mlaal lo-storablo ICPH h-uy.(,y) etrategfc nlitalle-epaeo laiinchAd ICBM BEF B-31d Component 01 01 2 ABRODyKAMIC LIFT h CONTBOL STBUCTUBE - BICID SKIN for A-]a hyperaonlc crulae high a l t i tude or low a l t i tude vehic le BBF B-93 Component 02 06 0 THRUST STBUCTURB for B-lb apace launch ayeteffl RBF B-83a, Propulsion Requirement Joining Ho 13 Cooponanta 02 05 0/16 01 0 SOLID ROCKET MOTOR CASE for B- la earth launch ayatcm-recoverablo booator, B-lb apace launch aystem A-4b atrataglc mlaallea REF B-134 Components 01 01 1/01 01 2 AEBODtNAHIC LIFT 6 CONTBOL STRUCTURE - RIGID SKIN for B-3b drag entry vehic les BSF B-107d 108a 109b, 111a b Components 02 01 0 SFACBCBAFT HULL, 02 02 0 SPACECBAFT lOTEBNAL STRUCTURE 02 03 0 SPACECRAFT EXTERNAL STRUCTURE 06 05 0/07 01 0 SOLAB COLLECTOR STRXTUBE/ANTENNA for B-2a near space operations spacecraft and B-2c spacecraft shutt le 2 ,02, pt< lt,»J,o, nolo, , I Colo, C/.e/./. .Otfilo. OtfilO S Y S T E M moBABiurr OOMDONEMT CRiriCMIir FRESUUIY OF n v t - T DESIQN ALTERNAra MATERIALS IMfUCATIOII AARP RAW 9 c a S E 3 r t e 4 It f - 6 S a 1 1 1 6 3 & 4-0 T « r A L « IZ f a 3 6 l> 33 8 9 s 3 ( 0 Â¥ ft 1 3 6 n 9 1 3 t 0 3/ It 3 % 6 e> 29 IZ It. 3 3 6 0 34 8 IZ a 3 6 t> 3Z n 6 3 3 6 0 3o e 6 8 3 t C> 36. IZ 6 3 3 6 i) 3e 8 6 8 3 6 0 36 IZ 9 3 3 i 0 33 t 9 3 3 0 39 IZ 9 1 3 i> 31 It f 3 3 0 33 It 9 1 3 6 0 31 1 6 o 0 X /lor AaltM 9 1 6 e 0 X 9 1 6 e 0 34> /» 9 a. i e B 9 Z 6 0 8 6 1 6 Â¥ 6 z s " IZ 9 » Â¥ 0 33 e 9 1 Â¥ 0 98 8 lb fZ 9 z C Â¥ (> 33 .A. y* . IZ 9 / & Â¥ 0 3Z IZ a / 3 0 ^6 , IZ. It 3 3 Â¥ 0 39 e IZ 3 3 Â¥ 0 3e IZ «> 3 3 Â¥ . 0 2g 8 6 3 5 t> 2Â¥ It 3 3 Â¥ 1Ì Z8
E X P L A N A T I O N O F C A M R R E F E R E N C E S T O S Y S T E M S , C O M P O N E N T S , A N D A A R P R A T I N G F A C T O R S CAMR CHART NUHSCR Â¥31 Â¥32 Â¥3Â¥ Continued from preceding page REF B-176 Component 06 04 Q IIEAT EXCilANCER fo r C-4a space power genera t ion r a d i a t o r REt P ropu l s ion Requirement Jo in in t , No 5 Component 22 04 0 CLOSED CYCLE TURBOELECTRIC POWER SYSTEM RADIATOR f o r B l b space launch systems f o r B-2a near space Operations spacecraf t and f o r B 2c spacecraf t shuc t l e REF B 123 Component 01 01 2 AERODYNAMIC LIFT i CONTROL STRUCTURE RIGID SUBSTRXTURE f o r B 3a l i f t r e - e n t r y veh i c l e s REF B 28d 39c A CompoiienL 01 03 0 NOSE f o r A 3a hypersonic c ru i s e h i i . h a l t i t u d e or low o U l t u d e veh i c l e s and A 3b hyperbonlc boost g l i d e s t r a t e g i c oi t a c t i c a l v e h i c l e s REF B 29c d 60c d Component 01 04 0 LEADING EDGE f o r A 3a and A 3b hypersonic v e h i c l e s as above REt P ropu l s ion Requirement J o i n i n g No 8 Component 13 01 0 RAMJET DIFFUShR LEADING EDGE f o r A 3a hyper- sonic c ru i se v e h i c l e s as obove A 4a(3) t a c t i c a l m i s s i l e SPiÌ H t o r A 4b B t i e t e g l c m i s s i l e s and B- l a e a r t h launch eystcus recoverable booster REF P ropu l s ion Requirements J o i n i n g No 10 11 Component 21 01 0 THERMOELECTRIC-THERMIONIC DXTING- PIPINC f o r B l a ear th launch systems B l b space launch systems B-2a(2) near space opera t ions space s t a t i o n B 2c spacecraf t s h u t t l e REF P ropu l s ion Requirements J o i n i n g No 10 11 Components 22 03 0 CLOSED CYCLE TURBOELECTRIC HEAT EXCtÌ MlGLH ant 22 05 0 DUCTING PIPItJC f o r I . l h { l ) ea r th I j unch ^ystcn ear th o r b i t launch B 2o(2) space s t a t i o n B 2a(3) lunar v e h i c l e and B 2c spacecraf t s h u t t l e Th i s CAMR Chart app l i es to a l l other f u s i o n welding 9 I char ts ond rt .ferences f o r them are Incorporated *fS^ I here in REF B n 4 a Components 01 01 1/01 01 2 AERODYNAMIC LIFT & CONTROL STRXTURES - RIGID S K I N / R I G I D SUBSTRXTURES f o r B 3b drag en t ry v e h i c l e s REF B 50o b Component 08 01 0 HEAT SHIELD fo r A 3c hypersonic HTOL o r b i t a l v e h i c l e REF P ropu l s ion Requirement J o i n i n g No 13 Component 16 01 0 SOLID ROCKET MQTOR CHAMBER f o r A 4 b { l ) s t r a t e g i c m i s s i l e s mobile ICBM A 4bC2) s to rab le ICBM f o r B la ea r th launch system recoverable booster B lb space launch system and B 2a neat space opera t ions spacecraf t 1 4 SYSTEM PROBABILir COMPONEN rCRITlCAim r FREBUCNCV ^ OF K Q V l t IN SYSTEM DtSICiN ALTERNA 1 MATERWL 3 IMPUCATIO , A A R P II RAW 3 C O R C S IX 8 4 I t 1 & S 3 1 1 â¢1 C. 3 TOTAL 5 .02.9X0, ,8,Z<i 3 3 Â¥ 0 2<< ,06.01,0, ,C </; It <f 1 3 _ y _ 0 ^9 OieSo, ,S,2A IZ 9 3 3 0 31 e>(. oS 0 , ^ 2 r e 1 3 3 0 2 7 0 2<) 0 31 ,22o<f_o 8,l,h 1% 9 / 2 12 9 3 y C 3 3 Â¥ t> 2</ 8 i 1 3 0 22 oloS o A 3 f t . 8 9 7. i> 0 xs o 3 o, ,A 3b _ â¢4- 9 I 3 ,el_o'/c ^/) 3 A 8 IT. 1. 3 0 e>/_o(/.o ,11 3i Â¥ 9 Z _ 3 1/ 0 S_s 13 oio A 3a. e n 2 3 u 0 J ? 0 y 11 "1.0. A'k^ 12 / 3 ( / .1.3.01,0, ,/? f/b 12. / t / 3 0 3 Z _ ?o / y o/o la. 8 '7L_ z 3 O .V.o'.o. ,ai.a,, 9 â¢2 3 9 l ^ z 4 12 t 2 3 _J*__ V 0 ?o ^ 0 3c .MP'.O ,S,2fikj IZ 9 2 _ ? a / e / , o 2 c ,3Scf3o pyhC'J _8__ IZ 9 <f 1 2 3 3 0 J o ,SgpXc, S.!o,ri) n 9 2 3 V ,«.<!».'', A^CV V 9 â¢z- 3 1/ 0 2 2 z.a o j o ,3Zc. e 9 ? 3 y 0 -24, 22 0^0 ,8.lh,0ll n 9 2 3 </ t> 3o ,22.<?i;o f,t,<tf^ n 9 2 y 9 0 3 c 23fi.So. , g Za/^) </ 9 3 V 0 ? 2 2 ? . » r » .H^n. e 9 tf 0 0.1.0.1,1. ,B}t>, 12 b _ / 3 o ^ 22 cdolo A-'ie Â¥ i2 1 3 <? :> 2o ,16^01.0, ,A Y^i) Â¥ 9 1 3 o "> 17 Itpio, AÂ¥^>) 12 9 / 3 0 c > 2 5 - e 9 _ / _ 3 _ > 7'
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS, AND AARP RATING FACTORS I CAMR CHARr NUMBCR ConttnuctJ f rom preceding pabe I 4S⬠REF B 3 Component 01 01 1 AERODYNAMIC LIFT & CONTROL STRUCTURE RIGID SKIN f o r A I subsonic long endurance a i r c r a f t REF B- l a Component 01 07 0 PRESSURE VESSELS ix TANKS f o r A - l a i r c r a f t as above REF D 6 Componenc 06 03 0 VECTOR CONTROL & THRUST DEFLECTOR f o r A - l a i r c r a f t as above REF B 30b c 61b c Component 01 01 1 AERODYNAMIC LIFT CONTROL STRXTURE-RIGIO SKIN f o r A-3a hyper snnlc c r u i s e h igh a l c l t u d e or low a l c U u d e v e h i c l e s Kiiil A - l b hypersonic boost g l i d e sCraceglc or t a c t i c a l veh i c l e s REF B 122c Component 01 01 1/08 01 0 AERODYNAMIC LIFT U CONTROL STRL-CTURES-RIGIO SKIN/HEAT SHIELD r o t K - i o l i l t r c -enc ry v e h i c l e s REF B 31b c 42b c Componenc 01 01 2 AERODYNAMIC L I U & LONIKUL iTKULiUKJib - KlGIU bUUirwuCTOKtb ror and A 3b hypersonic v e h i c l e s as above REF B-Slb component 01 06 0 lAADIHG EDGE f o r A-3e hypersonic HTOL-orblcal v e h i c l e REF B-50a b Component 08 01 0 HEAT SHIELD f o r A 3c v e h i c l e as above REF B-30a 6 l a Component 01 01 I AERODYNAMIC LIFT & CONTROL STRUCTURE-RIGID SKIN f o r A-3a hypersonic c r u i s e h i g h a l t i t u d e or low a l t i t u d e v c h l c l e a and A 3b hyperaonlc boost g l i d e s t r a t e g i c or t a c t i c a l veh I c l e e REF B-I22a Component 01 01 1/08 01 0 AERODYNAMIC LIFT & CONTROL STRUCTURES-RIGID SKIN/HKAT SHIELD f o r B-3a l i f t r e - e n t r y v e h l c l a s PEF B-31a 62a 123 Component 01 01 2 AERODYNAMIC LIFT 6 CONTROL STRUCTURE-RICID <:UBSTRUCTURE f o r A-3a and A-3b hypersonic v e h i c l e s es above REF B-2BC d Component 01 03 0 NOSE f o r A-3a hypersonic c ru i se v e h i c l e as above REF B-29b 5 lb Component 01 06 0 LEADING EDGE f o r A 3a hyperaonlc c ru i s e v e h i c l e s and A-3c hyperaonlc HTOL-orb l t a l v e h i c l e REF B-32e Component 06 01 0 AIR INLETS & DUCTING f o r A-3a hypersonic c ru i s e v e h i c l e s REF B- l lOa Component 06 06 0 HEAT EXCHANGER (RADIATOR) f o r B-2a near space opera t ions space- c r a f t and B 2c spacec ra f t s h u t t l e REF P ropu l s i on Requirements J o i n i n g No 8 11 Components 13 01 0 RAMJET DIFFUSBR LEADING EDGE and 13 03 0 RAMJET COHBUSTIOH CHAMBER f o r A-3a hypersonic c r u i s e v e h i c l e s f o r A-6a(3) t a c t i c a l ralsalle-SRBM f o r A-6b a t r a t e g l c m i s s i l e s and f o r B- l a e a r t h launch system recoverable booster REF P ropu la lon Requirements J o i n i n g No 9 11 Coovonent 18 05 0 CASEOUS POWER STSTEM HEAT EXCHANGER and 18 06 0 DUCTIKC-PIPING f o r A-2a supersonic h igh a l t i t u d e long range chemica l ly f u e l e d a i r c r a f t f o r A-2c supersonic t a c t i c a l V-STOL f i g h t e r f o r A-3a A-3b , and A-3c hyper- aonlc v e h l c l e a as above f o r A-6b a t r a t e g l c mlaa l l ea f o r B - l a e a r t h launch recoverable booster f o r B-2a spacec ra f t and B-2c spacecra f t s h u t t l e and B-3a l i f t r e - e n t r y v e h l c l e a i) SYSTEM PROBABILin COMPDNEnr CRlTICAinr FREQUENCY OF l a W T I N SYSTEM DESIGN ALTERMA ^ MATERIIttS I M H I CATION A A R P RAW SCORES 1^ e 4 I t 1 6 3 3 1 1 1 & 3 6 1-0 T » T A t s I^Pl.o, A'?-., e 9 / 3 0 l > Z/ .li,olp, IZ 9 1 3 0 0 z r (b.ol,l>, IZ 9 1 3 0 ,O.UO.I,l. Ai , , e 6 2 3 i. 0 2 r .0.1.Oft 0, . H . , 8 6, 2 3 i .Cli.oSo, . e 9 2 3 <s 0 .O.I^OI,I, .D ?<^, e IZ 2 3 £ .''l.'.l.l, 1 '9-.3.b, Â¥ 12 2 . 3 C 0 27 , 01, el 1 3a., e IZ 1 3 6 0_3o_ el, CI g A?9- i 6 â¢2, 3 C 0 z r ol o/ 1 9 2 3 £ 0 zv ol O^e __9_ 2 3 0 _ 21 _ CSoic A ? r , / z 2 . 3 c. 0 2 7 _ 01^01,1, e li 3 _ ^ _ 3 Â¥^ 0 ,o\el 1, A ?b. Â¥ /z 3 3 V _ 2£ .01,01,1 .s.h. It 3 </ r 3 c 01.oil 2 A h-. e 6 3___ 5 " 0 2 V .0.1 01,^: .A ?i>. <r 3 0 ^ 3 _ .0,I.OI,l, A l t . g 3 3 e.1,0^0 A?f^. g â¢3 V el Qi/o ,/l3a.. t IZ- 7 u C>__ 3 ' ^ _ 9_ â¢z u a( ol 0 /I 3A _ 1/ Oi.O'/c, .SZa ij- / z 3 < ~l 0 _ l v oi o</e 1- / 2 . 3 </_ 0 2 ' I3.o.l,0, A?fi. It 3 0 0 ''<⢠nolo Alttr AitfUee / t 1 1/ 13,01,0 ^/>fh, It It 2 </ 0 3 3 13.01,0. . e IZ 3 3 c> 3c. /S.eSe AZa It c 3 3 « 0 -2-5 le.oio , 6 3 3 0 ^ « _ _ ./e,pin A?f^. 8 6 3 3 9â ie,»so Â¥ 6. 3 <* / t , Cfto A,3c 2 V 1> 2 4
EXPLA^4ATI0N OF CAMR REFERENCES TO SYSTEMS. COMPONENTS, AND AARP RATING FACTORS CAK4R CHAItr NUHSCR Â¥37 VÂ¥3B Continued fiOD pTccedlog paga BEP Propulsion Boqulrement Joining No l i t Conponanc 10 03 0 TUBfiOJST VAKB8. and 10 06 0 TURBOmT AFTBR- BUBKBB COKBCSTIOB CBAMBBR for A-2a and A-2c super- sonic a i r c r a f t as above, fox A-3a hypersonic cru i se v e h i c l e s , and B - l a earth launch recoverable booster Conqionent 16 03 0 LIQUID ROCKET NOZZLE for B - l a earth launch recoverable booster B-lb space launch system B-2a spacecraft and B-2c spacecraft shutt le Component 22 03 0 CLOSED CTCLE TUBBOBUCT&IC HEAT EXCHABCER for B- lb space launch systems. B-2a spacecraft and B-2c spacecraft shutt le REP B-30a 41a Component 01 01 1 ABROOniAMIC LIFT & CONTROL STRUCTURE-RIGID SKIN for A-3a hyperaonlc cru i se high a l t i tude or low a l t i tude vehic les and A-3b hypersonic boost gl ide s tra teg ic or t a c t i c s ! vehic les REF B-122a Coiiq>onent 01 01 1/08 01 0 AERODYNAMIC L I F T & COOTBOL STRUCTURES-RIGID SKIN/HEAT SHIELD for B-3a l i f t re-entry vehic les REP B-S l s 42a 123 Component 01 01 2 AEBODTNAMIC L I F T & CONTROL STRUCTURES-RIGID SUBSTRUCTURES for A-3s and A-3b hypersonic vehic les as above, and B-3a l i f t re-entry vehic le B-28c Component 01 03 0 NOSE for A-3s hypersonic c r u i s e v e h i c l e as above SEP B-29b Sib Component 01 04 0 LBADINC EDGE for A-3a hypersonic cruise vehic les and A-3c hypersonic HTOL-orbltal vehic le H ii IS At A ,f>Â¥ll. SYSTEM PROSABILin COMPONENT CRITICALITr FRESUCNCY OF roviT IN SYSTEM DESIGN ALTERNA i3 MATeRIAlS IMFUCATIOI AARP RAW S C O R E S \i e 1* It 1 6 3 3 1. i S fc 3 X * T A L S 12 6 z 3 Â¥ i> 27 0 2 7 ,l.8.oS,oi ,f-(at, s 9 3 3 1 /fioso, ,8?0'. 12 9 3 1 0 3) ,/e,es,o, , 8-3^ 6 3 3 9 .Ig.l^o, ,l}-3o-. 8 9 3 3 0 27 ./t,06o, , />.ZA. 12 6 3 3 9 0 2S ,(t,o6e, , ^ ? c , 12 6 3 7 1 ./.*.«<.'. , /??<>, 9 6 3 3 <f 0 ^ ,/$,o6.o, ,/l3l>, Â¥ 6 3 z. 3 f 0 I t .ll,o/ifO, ,/}?,e. 4 3 1 0 It.oi^o, ,/( Â¥i>. It 9 2 3 1 0 Jo ,/S.oi.o, t/8-l<^ . 8 9 3 3 9 0 27 ,iS.o6o. It 9 3 3 1 0 31 0 " le.oio ,8?-f'. V C 3 3 9 /go6,o ,S 3,0, 6 12 9 3 S 9 /OAXO. f / f Z A , 9 3 3 3 _ y _ /eoXo, ,/> Ze 12 <? 3 0 _ J I _ _ ^3 0 . /e,o3 0 . / f 3/^ /p,o3c ,8./f~. r 9 3 3 3 3 3 8 12 12 9 3 yo^ot,' , / f2o 6 3 yo.oio ,^ZC 9 3 9 ,/oul,B, ,i4,3,6 e & f 3 2 3 ^ _ i L >Ì Â« 7 /o p^-o , ^/«, 3 ./io\o, .8:ff^. 3 3 It. 9 Z 3 3 ,/f,,o3,o ,8.^. 1% 6 3 0 /i,oS 0 , 8ze 6 3 _ J 3 V .%zttio 8 ii> 12. 9 Z V 6 3o Zl.olo ,82o. / t 9 3 u. t> â¢22,03.0. .B2C C 3 3 At .01,01,1 A3<f. e 12 3 3 0 30 oloil ,D,3,i, 12 3 3 9 ol ot 1 ^8 3a 12 3 3 9 e> 3o pi. 012 . 3a e 6 3 3 9 0 z<^ pi pi I A 3^ 9 3 3 9 0 23 ,e/,p/;t .83a. e 6 3 3 9 i;> z9 m 03o /13a e 9 3 3 9 0 2T ,oiP^o <*3A B IZ 3 3 9 i> 3o
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS. AND AARP RATING FACTORS ! CAMR CHA«r Continued f r o m preceding page ^3B Component 06 01 0 AIR INLETS & 1 DUCTING f o r A-3a hypersonic c r u i s e v e h i c l e s RBF B- l lOa CompononC 06 04 0 HSAT EXCHANGER (RADIATOR) f o r B-2s near space opors t iona space- c r a f t end B-2c spacec ra f t s h u t t l e REP P r o p u l s i o n Requirement J o i n i n g No 5 Components 22 OA 0 CLOSED CYCLES TURBOELECTRIC RADIATOR, and 22 OS 0 DUCTIMC-PIPING f o r B - l b space launch aystcms B-2a near space oporo t ions s p a c e c r a f t , snd B-2c spacecra f t s h u t t l e REF P ropu l s i on Requirements J o i n i n g No 8. 11 Components 13 01 0 RAMJET DIFFUSER LEADING EDGE and 13 03 0 RAMJET COMBUSTION CHAMBER f o r A-3o hypersonic c ru i s e v e h i c l e s , f o r A-4a{3) t a c t i c a l mlsslla-SRBM, f o r A-4b s t r a t e g i c m i s s i l e s , and f o r B- l a ea r th Isunch system recoverable booster REF P ropu l s i on Requirements J o i n i n g Ho 9, 11 Components 18 05 0 GASEOUS POWER SYSTEM HEAT EXCHANGER and 18 06 0 DUCTINC-PIPINC f o r A-2a supersonic high a l t i t u d e long range chemica l ly f u e l e d a i r c r a f t f o r A-2c supersonic t a c t i c a l V-STOL f i g h t e r , f o r A-3a, A-3b, and A-3c hypetaonlc v e h i c l e s as above, f o r A-Ab s t r a t e g i c m l a s i l o s , f o r B- l a e a r t h launch recoverable boos ter , f o r B-2a spacecra f t and B-2c spacec ra f t s h u t t l e , and B-3a l i f t r e - e n t r y veh i c l e s REF Propu l s ion Requirements J o i n i n g No 10,11 Component 21 01 0 THERMOELECTRIC-THERMIONIC DUCTINC-PIPINC f o r B - l a , B - l b , B-2a, B-2c systems as above Component 22 03 0 CLOSED CYCLE TURBOELECTRIC HEAT EXCHANGER f o r B - l b , B-2a B-2c systems as above S Y S r t M PROSABILir OOMPDHQfl I CRITICAUTr FREBUENCY OF M M t IN SYSTEM PESIGN ALTERNAi'i: MATERIAL 3 IMfUCATia A A R P RAW SCORES i f 0" " o t f 11- e 1* l l - ' ) - 6 - S a i-\ 3 ,«?/,<?<<<, .^3,<r, y 9 2 3 Â¥ t> Z2 PiOl.p. .^-y^ 8 9 3 3 y 0 2-7 tx 12 3 3 <t 0 3 * aC.eif.0, 4* 12 3 3 y 0 26 /2 9 3 3 y i> 3/ ^.ofo, t% 9 3 3 y 0 3/ .â¢i^!0<f.<t . B-2C. Â¥ 6 3 3 y 0 l(> ,22ASO. , 8/^, It. 9 3 3 y 0 31 ,22,air.o ,? '2a, f2 9 3 3 y 0 31 Z2of<i ,^-^e Â¥ 9 3 3 y 0 23 .13,01,0, .A^Cf., 8 tz 3 3 y lO 3o .fSAip. A.-Hof^ It 2 3 y 0 X ./3/>/P. .tf-f^. / Z It 3 3 0 3<* 13 01. 0 , B'/ti e It 3 3 y 0 3o i3ts,o, ,Ì -3f>. 8 9 3 3 y 0 21 .13.030 ,A â¢l;it) Attr Anfatet 9 Z 3 <f ,/,3.<?39 A-yi; tZ 9 3 3 y e> 31 ,13,03 0 , B;^C. B 9 3 3 y 0 21 .IfAS-o. AU, tz 6 2 3 V i> 21 /Z & 2 3 It 0 21 .tB.e.S-A i^?*?. 8 6 3 3 y 0 2<^ .tSp.SA. Â¥ C 3 3 V 0 16 Â¥ 9 2 3 y 0 22. tz & 3 3 Â¥ 0 Zi A<9. 8 9 3 3 y 0 27 ffiPiO ,B?f>: 12 9 3 3 6 31 ./.i.'^o ,B.2e y 6 3 3 V 0 lb ./g.oin .83A 8 9 3 3 y e> zi â¢ffM". 12 C 2 3 <i C> 27 ,/$,o,(,o, .A-2,e, 11 6 2 3 0 21 0 6 3 3 Â¥ 1Ì 24 ,/f,o£,^>, ,A3,6, 6 3 3 ,/e,M.o . /I,3,C, V 9 2 3 it I > 2Z /t.otp , /i.Yi> 12 C 3 3 V ,/e,ot,p ,B;/a 8 9 3 3 y i> 27 ,/,e,e<o .B,Za It 9 3 I y 0 31 ,/eoio B:Ze Â¥ t 3 3 y 0 It /S, pt,e, 8,'?"- 8 9 3 « 0 27 2/,-oi,e, S-ifa e 9 3 3 y [> 27 ,zi,o.i.c 8:/6, 12 9 3 3 y * 31
EXPLANATION OF CAMR REFERENCES TO SYSTEMS. COMPONENTS, AND AARP RATING FACTORS CAMR e i u R r N U M U R Â¥38 439\ Â¥4o ¥¥l\ ¥¥%. ¥¥$ Coaclnued f ioo p i s c e d l D g page BBF B-126at Componant 09 01 0 B-3a l i f t r e - « n t x y vehic le BBABIK for BBP Propult lon Bequlcemenc Joining No I t Coovonanta 14 01 0 LIQUID ROCKET MDTOB COMBUSIION CHAMBBR 14 02 0 LIQUID ROCKET MOTOR NOZZLB and 16 03 0 SOLID ROCKET MOTOR NOZZLB for A-4b i t r a t e g l c ffllssiles B - l a earth lounch recovaxabla booster and B- lb apace launch ayetems BBP B-172ai GoopooenC 08 06 0 PBB88URE SUIT for C 3a emtxa-vehlcular/advanced apace aulc l i f e aupport aystem BBP B-147 Coo^nent OS 03 0 8UBPACB COmACT EBVICB for B-4a ( l ) earth tangential landing ayoteaa EBP B-8Sa b c 14Sb Cosvonents 01 02 0 ABRODYNAMIC LIFT & CONTROL ffTRUCTUBES ⢠FLBXIBL8 and 01 02 1 PUX VINC 01 02 3 FLEX DBCBLBRATOR 01 02 4 FLEX BOTOS for & la earth Launch ayscsm recovorabla booster and B-4a earth landing ayatems - tangential and v e r t i c a l BBF B-84 Conpoaant 02 07 0 IwrBBSXACB AND IWIBaiAia STRUCTURE for B l a earth launch recoverable booster BBF B 50a Conqionant 08 01 0 UBAT SBIBLD for A-3c hypersonic HTOL-orbital vehic le BBF B-97b Componant 08 01 0/08 04 0 HEAT SHIELD/ BROSION-COBBOSION SHIELD for B- lb space launch systetD ,91.01.0. .7Z,o3.o, ,/^olo, J9,o2.o /Â¥o2o, /(.o.3^, ./i.oJ.o ./< 03 o 0,8 c/o. S Y S T t M PROBAaiLin COMraNENT cRir icAinr FREaUCNCV OF m v i T IN SYSTEM DESIGN ALTERNA MATERIALS 1 IHruCAnON AARP RAW SCORES n e t I t â¢) 6 S 3 1 1 <l C. 3 ft. 9 3 3 Â¥ i> 31 .839, 4 9 3 3 ** 0 » 3 _glb , It 9 3 3 Â¥ 0 31 .8^. It 9 3 3 Â¥ 0 Â¥ 9 3 3 Â¥ 0 23 ^8H, a 3 1 3 0 /9 9 2. 9 0 36, 0 J 2 ,?/^, 8 f 2 9 V 12 9 2 9 0 36 i> 36 /Z- 9 1 9 Â¥ , ^^9 8 9 7 9 9 0 32 , 8-./^. 1% 9 â¢2 0 36 n 9 2. 9 Â¥ 0 36 8 9 7. 9 _ Â¥ V 0 32 36 12- 2 9 .^.?9. /2 9 / 3 o Am 8 & 1 3 Â¥ d 21 8 12 1 3 0 3c 12 It 2. I C> ss 12 9 % 3 6 0 3Z Ar{<^, l^ 1% L j" 6. i> 3^ e 3 1 2 e> 0 iÂ¥ A ?p Â¥ /2 / 2 o i> ^9 /2. 6 / 2- e> 0 21
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS. AND AARP RATING FACTORS CAMR CHASr NUHUK. ¥¥t\ BEP B-30a, 61&. CODpoDent 01 01 1 ABBODniAMIC LIFT h CONTROL 3TB.UCTUBBâ¢KIGID SVIN f o r A*3a hypersonic c r u l a e h i g h a l t i t u d e or low a l t i t u d e v e h i c l e s and A-3b hyperaonlc booat g l i d e a t r a t e g l c or t a c t i c a l v e h l c l e a REF B-31a, 62a Cooponant 01 01 2 ABBODYNAHIC LIFT & CONTROL muCTUBES - RIGID SUBSTRDCTDBBS fox A-3a and A-3b hyperaonlc v e h l c l e a as above. BBF B-28c ,d , 39c Component 01 03.0 NOSE f o r A-3a hypersonic c r u i s e v e h i c l e s and A-3b hypersonic booat g l i d e v e h i c l e s RBF B-29b ,c . 4 0 c , d , 5Lb, I20a.c Component 01 06 0 LSAOING BOGB f o r A-3a and A-3b v e h l c l e a aa above, A-3c hypersonic HTOL-orb l t a l v e h i c l e , and B-3a H a t r e - e n t r y v e h i c l e REF B-32a Component 06 01 0 AIR DtLETS & DUCTING f o r A-3e hyperaonlc c r u i s e v e h i c l e s REF B-50a, 121a Component 08 01 0 HEAT SHIELD f o r A-3c hypersonic HTOL-orb l t a l v e h l c l e a and B-3a l i f t r e - e n t r y v e h i c l e s REF P ropu l s ion Requirement J o i n i n g No 8 Component 13 01 0 RAMJET DIFPUSER LEADING EDGES f o x A-3e hyperaonlc c r u i s e v e h U l e a , f o r A-6a(3) t a c t i c a l mlss l le-SBBH, f o r A-4b s t r a t e g i c m i a s l l e s , and f o r B - l a e a r t h launch recoverable booster REF B-30c. 6 l c Cooponent 01 01 1 AERODYNAMIC LIFT & CONTROL STRUCTUBB-RIGID SKIN f o r A-3a hyperaonlc c ru l ae h i g h a l t i t u d e or low a l c l t u d e v e h i c l e s and A-3b hypersonic boost g l i d e a t r a t e g l c or t a c t i c a l v e h i c l e s RBF B-122b Component 01 01 1/08 01 0 ABRODTNAHXC L U T ix CONTROL STRUCTUBE-BICID SKIN/HEAT SHIELD f o r B-3a l i f t r e - e n t r y v e h i c l e s RBF B-31c, 62c Coiq>onent 01 01 2 ABRODTNAMIC LIFT t. CONTROL STRUCTUBBS-BICID SUBSTRUCTUHKS f o r A-3a and A-3b hypersonic v e h i c l e s as above REF B-S2a Component 01 03 0 HOSE f o r A-3c hypersonic HTOL-orb l t a l v e h i c l e REF B-51b Component 01 06 0 LEADING ErcB f o r A-3c v e h i c l e as above REF B-18c Component 01 08 0 HAJOR FITTINGS f o r A-2b supersonic h i g h a l t i t u d e long range nuclear powered a i r c r a f t REF 15a. 32b Component 06 01 0 AIR INLETS & DUCTING f o r A-2 supersonic a i r c r a f t and A-3s hypersonic c r u i s e v e h i c l e s REF P ropu la lon Requirement J o i n i n g Ho 12 Component 13 01 0 RAMJET DIFFUSBR LEADING EDGE end 13 02 0 DIFFUSER SKINS f o r A-3o and A-3b hyperaonlc veh i c l e? as above f o r A-6a(3) t a c C l c o l mlaalles-SRBH, and f o r B- l a e a r t h launch recoverable booster it ti ,01.0,1,1, ,H3a,, SYSTEM PROBABILirt coMPDNatr CRITICAIITV FREaUUCY OF savtT IN SYSTEM DESIQN ALTERNAV3 MATERIfllS IMUJCATiail A A R P VJAW s c o e e s i t e 4 I t 3 t - l 3 6 1 - 0 T a T A L K 8 IZ 2 3, 3 Â¥ <> 3o .01.01,1, A U . Â¥ IZ 3 V 0 M, .Oi.»I..Z e 6 3 3 Â¥ 0 24* ei.a/.y ,/l,-36 Â¥ 9 3 3 Â¥ 0 23 el.ole /13a. e 9 3 3 0 27 ,al,c,3e ^/f V 9 3 3 9 0 35 0 22 fil oi/e, ,/> 3a , e 11 3 3 « / _ o / 0 A, -f^ . 9 3 3 e < / o A , V 9 3 3 tf/e/e .S,-3a. e 2 3 V 0 26 ,et^ol o, ,/), ? a . e It 3 0 3e ,ot,oi o, ,/>3e , Â¥ 2 b 0 28 ,o«,oio ,^3f.. e IZ â¢X Â¥ 0_3Z__ t> 33 0 X 0 3S- ,l3al,o i ^ ? ? ^ e It 3 i >/ ,l3,elo A. 'hf^j / V . r /Z It 1 £ l3,cl,o, â¢/b. It It 1 C ,13,01,0, ,^â¢/0L, 8 1 C Â¥ 0 31 0 2 2 0 28 .01,01.1, A.^. 8 IZ 5 â¢3 6 olol.l A?/'. Â¥ fZ 3 3 3 6 ,01,01,1 ,g-3fi.. 8 _ / 2 _ 6 / _ C, 6 0 3o 8 3 3 3 0 2 « ,0,1 o / , ? , ,/) 3t, Â¥ 9 3 6 zs ,61,030 ,11 30 9 Z I 6 __C & 6 2C O.loÂ¥o A ? f . 9 2 3 ^ â¢Â»</ OI,ee.c ,A,-Zb Â¥ 9 t 3 ,0(010 IZ^ 3 %⢠? 3 £ 6 6 31 ,l3jilo^ fi, ,l3,oi,c, ,D 3b . 13 ol 0 ^"^^(^1 8 It 3 3 2 Â¥ .ALt.fiiitte e It I t 3 & 3 0 X I t â¢Â» 3 t> 3 / .note ,Al(L, 9 3 6 0 2 9 n,olo A/^h Â¥ 9 3 t 0 IS liol.c fl.Ho,^/ AmPeiuc 8 9 2 3 6 i) X l}^i.o. .B-la., 9 7, s 0 ze
EXPLANATION OF CAMR REFERENCES TO SYSTEMS, COMPONENTS, AND AARP RATING FACTORS I CAMR euMtr NUHBCR. BB? B-49: Cocvonent 01.01.1 AEROITOUac L I P I & COHTEOI. STElJCtmE - RIGID SRIN for A-3c hyper- sonic BTOL*orbltal vehicle. BSP B-122b: Cooponeiit 01.01.1/08.01.0 ABRODSTOMIC L m & COBTROL STRUnUBZ-RIGID SKIN/HIAT SHIEUI for B-3a l i f t re-entry v e h i c l e s . RBP B-92, 97a: Cooponents 02.06.0 TBRUST 8TRXTUBE and 02.07.0 IHIBRSnGZ & DRSSnNR SIBUCIUBK for B - l b ( l ) and B-lb(2) space launch systems - earth orb i t launch and lunar launch. BSF Propulsion Requirement Joining No. 5: Component 22.04.0 ClOSBD CTCIB HJRB0BUCIRIC 70UER STSTKH RADIATORS end 22.05.0 OUCTDC-PIFIli: for B - l b ( l ) and B-lb(2) space launch systems es above and B-2e(2) space stetions. // ,»2 et-o. e%o6-o 02. »7o et 070, 11 eV.o ZtoCo ii SYSTtM PROBABILir C0MP0NEN1 (CRITICAUTY FRESUCNCV OF KUMIr IN SYSTEM DESIQN ALTERKIA-^ MATERIWa 3 IMIUCATIO) A A R P RAW S C O R E S I t - 8 - 1 3 1\ 1 - t 3 6 - 4 - 0 T O T A L S 6 1 0 /7 8 /Z- 1 3 0 0 2Â¥ 9 3 t, e> 0 3o Â¥ f 3 C 0 22 'H') /* 3 A e> i7 6 3 0 0 19 s';'l>('li 12 9 3 3 ⢠0 9 3 3 0 0 f9 n f 3 3 0 0 27 f 3 3 0 1 1 ⢠⢠J e> 1 , . . . 0 0 1 1 . 1 . 0 0 1 1 ⢠1 ⢠1 . . . ⢠0 0 ' ⢠' ' 1 0 1 . . . . 0 0 1 ⢠⢠1 L 1-1-1â1 1 i> 6 i> 0 C t> t> 0 1 i> l - . - L . i 1 0 0
APPENDIX A SYSTEMS CODE
