FIGURE 7.1c

U.S. SUPPLIES AND USES OF PLASTICS



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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering FIGURE 7.1c U.S. SUPPLIES AND USES OF PLASTICS

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.1 Annual Requirements for Principal Primary Materials Used in the United States (Pounds per capita, 1972) A. Nonmetallic Inorganic Materials:     Sand and gravel 9000   Stone 8500   Cement 800   Clays 600   Salt 450   Other 1200 20550 B. Metals:     Iron and steel 1200   Aluminum 50   Copper 25   Lead 15   Zinc 15   Other 35 1340 C. Natural Organic Materials:     Forest products 2750   Natural fibers and oils 50   Natural rubber 10 2810 D. Synthetic Organic Materials:     Synthetic polymers 116   (including rubber)   116   TOTAL 24816 (Equivalent total for entire U.S. population = 2.57 billion short tons.)

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering technology that may make it feasible to mine down to 4 pounds per ton. While advances in extraction technology are capable of easing our dependence on foreign sources of raw materials, improved technology in other stages of the materials cycle could enhance the effectiveness of materials utilization and hence relieve pressure on new supply. Figure 2.4 of Chapter 2*illustrates some of the social and technical pressures that operate at various stages of the economic utilization of materials. A strong materials technology is a key element in permitting industry to be responsive to these pressures and yet still produce goods at reasonable cost. MATERIALS IN INDUSTRY Consideration was directed in Chapter 2 to the changing world conditions in which the institutions of the materials field—in industry, government, and universities—must function. Attention is now given to illustrating in more detail the principal features of industrial areas which operate to meet man’s present and future needs for materials to perform desired functions in goods and services. The features are highlighted by examining three key materials-producing industries (metals, inorganic nonmetals, and plastics), and five industries that are major users of materials (electronics, lighting, containers, automobile, and building). Finally, in the closing part of this section, the important role of materials standards and specifications is reviewed. Before discussing the individual industries, it is useful to view their relative efforts devoted to process and product improvement and innovation through their R&D activities. Although accurate information for these industries is unavailable, some comparison with the full range of U.S. manufacturing industry is given by data in Tables 2.19, 2.20, and 2.21 of Chapter 2. The industries listed in these tables are the Standard Industry Classification (SIC) sectors often used in national statistics. While these sectors do not always exactly match the industries to be discussed here, they are close enough to indicate two important points. The first is that the metals and inorganic-nonmetals producing industries—like most primary product industries—show R&D expenditures that are considerably smaller in absolute terms than the four industry sectors leading the list, and they also stand lower as a proportion of the industry sales revenue. The second point is that, unlike the leading industries (except for chemicals, in which the plastics industry would be included), these materials-producing industries essentially fund their own R&D and receive little federal R&D support. While presently available national statistics do not permit a more detailed analysis of industrial materials R&D, Table 2.21 indicates that total R&D in the materials-producing industries is somewhat more than one billion dollars, almost all of which is supported by industrial funds. In addition, a substantial amount of R&D is carried out in the materials-using industries, although the actual dollar value has not been ascertained. *   Tables and Figures referred to on this page can be found in Chapter 2, Volume I of this Series.

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering Principal Materials-Producing Industries Metals Industry Table 7.2 shows the expected demand for metals over the next 15 years. Iron and steel continue to be the leading metals industry in scale and value and a significant indicator of the nation’s economic wellbeing. In terms of both quantity and value, aluminum and copper are the principal metals in the nonferrous group. They are followed by 44 other elements, ranging from the precious metals, gold, silver, and platinum, with very high unit values but relatively small volume usage, through the industrial metals such as lead, zinc, mercury, and the light metals such as magnesium and titanium. Major applications and future growth areas are strongly oriented toward consumer goods, transportation and construction industries, and the generation and use of electrical energy. Continuing increases in the real costs of production and an anticipated growth in utilization are the principal factors contributing to an increase in domestic demand for the nonferrous commodities (from about 15% of the 1970 value for all mineral commodities up to about 18% of the total in 1985). Industry Structure: A large part of the metals industry is concentrated, i.e. is characterized by large vertically integrated companies which are able to optimize both their raw materials sources and their markets. Major factors leading to this structure are the worldwide occurrences of ores and raw materials and the complex coproduct-byproduct relationships. Thus, dispersion of raw material sources encourages formation of multinational companies, and broad-based markets results from the production of the many metals of interrelated occurrence. The latter is especially true in the base metals. The significance of imports and import sources to the U.S. is illustrated in Table 7.3. Similarly, Table 7.4 shows the metal byproducts recovered in the processing of ores for the major metal content. A tendency toward horizontal integration along functional lines has developed during the last two decades. For example, major copper-producing companies have expanded their operations to include production of primary aluminum. Primary aluminum producers are likely to become involved in primary copper production within the next decade. Because of the many common markets shared by the light metals, aluminum, magnesium, and titanium, the production and processing of two or more of these elements by single firms will tend to expand during the remainder of this century. The similarities in uses and properties of titanium and alloys of iron have already led steel companies to invest in primary production facilities for both of these elements. The following paragraphs illustrate these various structural features for specific metals industries. In iron and steel, an estimated 60% of domestic iron ore production was accounted for by nine steel companies; these same organizations produced about 75% of the nation’s crude steel in 1970. The two largest U.S. companies produced 34% of the domestic iron ore, 40% of the crude steel, and also accounted for the bulk of U.S. imports of iron ore from mines in Canada, Venezuela, Liberia, and Chile.

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.2 U.S. Demand for Selected Primary Metals, 1970 and 1985*     Demand Growth, percent Metal Units 1970 1985 Annual Compound Total 1970–1985 Ferrous:   Iron Million S.T. 84 113 2.0 135 Manganese Thousand S.T. 1,327 1,770 1.9 135 Chromium Thousand S.T. 462 700 2.8 150 Vanadium S.T. 7,066 14,700 5.0 210 Nickel Thousand lb. 311,400 492,200 3.1 160 Molybdenum Thousand lb. 49,104 96,500 4.6 195 Tungsten Thousand lb. 16,200 34,200 5.1 210 Nonferrous:   Aluminum Thousand S.T. 3,951 11,500 7.4 290 Copper Thousand S.T. 1,572 2,900 4.2 185 Zinc Thousand S.T. 1,302 1,820 2.3 140 Lead Thousand S.T. 829 1,100 1.8 130 Magnesium** Thousand S.T. 96 235 6.1 245 Tin Thousand L.T. 53 70 1.9 130 Titanium** Thousand S.T. 24 65 6.9 270 Mercury Thousand fl. (flasks) 54 66 1.3 120 Silver Thousand Troy oz. 73,100 124,000 3.6 170 Gold Thousand Troy oz. 6,147 9,200 2.7 150 Platinum Thousand Troy oz. 407 634 3.0 155 * From First Annual Report of Secretary of the U.S. Department of Interior, March 1972. ** Metal only, all others include both metallic and nonmetallic applications.

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.3 U.S. Imports by Source and as Percent of Apparent Consumption, 1970 Metal Imports /Consumption, percent Major Import Source Ferrous: Iron 33 Canada, Venezuela Manganese 82 Brazil, Gabon, Rep. South Africa, India Chromium 84 U.S.S.R., Rep. South Africa, Turkey, Philippines Vanadium 29 Rep. South Africa, U.S.S.R., Chile Nickel 75 Canada, Norway Molybdenum Nil   Tungsten 8 Canada, Peru, Mexico Nonferrous: Aluminum 118 Jamaica, Surinam, Canada, Australia Copper 19 Chile, Peru, Canada Zinc 51 Canada, Mexico, Peru Lead 27 Canada, Australia, Peru, Mexico Magnesium* 3 Canada Tin 76 Malaysia, Thailand Titanium* 40 Japan, U.S.S.R. Mercury 35 Canada, Spain Silver 48 Canada, Peru, Mexico, Honduras Gold 47 Canada, Switzerland, United Kingdom, Nicaragua Platinum 139 United Kingdom, Rep. South Africa, Japan, U.S.S.R. * Metal only, all others include both metallic and nonmetallic applications.

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.4 Byproduct Relationships for Selected Metals, 1970 Ore 100 Percent of Total Output Less Than 100 Percent of Total Output Iron Cobalt   Manganese Copper Gold Silver Aluminum   Gallium   Copper Arsenic Rhenium Selenium Palladium Tellurium Gold Silver Molybdenum Platinum Nickel Zinc Iron Lead Lead Bismuth   Antimony Zinc Silver Tellurium Gold Copper Manganese Zinc Cadmium Germanium Indium Thallium Lead Silver Manganese Gallium Gold Mercury Copper

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering In aluminum, four of the 12 domestic firms producing primary aluminum and representing about 72% of total productive capacity in 1970 were vertically integrated from mining through production of semifabricated shapes. Two of the remaining firms were owned or associated with foreign integrated firms. Others produced aluminum from purchased bauxite or alumina, and all had facilities for producing semifabricated shapes. Worldwide, the aluminum industry is vertically integrated with very few exceptions. Six companies control or influence (by majority or minority interests) over 75% of the world productive capacity for primary aluminum. In copper, 25 mines accounted for 93% of the U.S. copper output in 1970. The five largest produced 42%, and three companies accounted for a little more than half of the domestic mine production. Virtually all copper ore continued to be treated at concentrators near the mines. Concentrates were processed at 17 smelters—eight in Arizona and one each in Utah, Michigan, Montana, Nevada, New Mexico, Tennessee, Texas, New Jersey, and Washington. Copper smelting capacity in the U.S. in 1970 totaled 9.2 million tons of charge, equivalent to about 1.9 million tons of smelter product; four companies constituted nearly 80% of the capacity. Refinery capacity totaled 2.7 million tons of which 89% was electrolytic refining capacity and 11% was fire-refining (including Lake copper) capacity. Many large domestic copper producers, through subsidiaries or stock holdings, operate or control foreign copper-producing properties in Canada, Mexico, Peru, the Republic of South Africa, and Zambia. In addition to copper and the usual byproducts, some of these companies are also major producers of aluminum, cadmium, chromium, germanium, lead, titanium, uranium, vanadium, zinc, asbestos, fluorspar, precious metals, and liquid and solid fuels. In lead, domestic companies accounted for 61% of the lead mined and practically all of the primary smelter production in 1970. These large companies are vertically integrated (from mine to refined lead) and are also horizontally integrated with other base-metal production. Other companies in the industry are essentially mine operators utilizing, to a varying degree, custom plants for concentration, smelting, and refining. The leading 25 mines accounted for over 95%, and the leading 5 mines for 64% of the total domestic primary production in 1970. Four states produced 97% of the total domestic production; Missouri contributed 74%; Idaho, 11%; Utah, 8%; and Colorado, 4%. In zinc, companies prominent in the U.S. zinc mining or smelting industry likewise have substantial interests in important mines and related operations in foreign countries. Conversely, certain foreign firms have significant interests in segments of the U.S. zinc industry. In 1970, the primary zinc producing industry in the U.S. was dominated by six large vertically integrated firms that controlled mines, smelters, and/or refineries. These six, along with one company having only an electrolytic refiner, accounted for 90% of the slab zinc produced domestically. Nine prominent U.S. companies have substantial interests in foreign zinc activities. Holdings are in properties located in Canada, Mexico, Argentina, Peru, Australia, and southwestern Africa. Recycling of Metals: Published statistics on the reuse of metal wastes through recycling are frequently confusing in that they often fail to distinguish between scrap recovered from the materials-producing or using

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering industry (home or prompt industrial scrap) and that derived from post-consumer wastes (old scrap) or imports. Figure 7.2, which is based on the aluminum industry, illustrates the origins of these types of scrap at the different stages of metal flow through the materials system. Clear delineation of these separate scrap sources is especially important in the light of current material concerns about the management of waste or residual flows for purposes of environmental protection and materials conservation. Table 7.5 shows the current levels of total scrap recovered in the U.S. for the major metals. These data indicate the modest recovery of secondary aluminum and zinc (17% of consumption) compared with that for secondary copper (i.e. copper recovered from scrap as metal, as alloys without separation of the copper, or as compounds). Both the intrinsic value and long-established recovery technologies contribute to the higher rate for copper. The largest amount recovered as metal is reclaimed by the primary copper producers as electrolytic copper. However, alloyed copper, principally brass and bronze, comprises more than 50% of the total recovery and is prepared by secondary smelting and casting processes. Lead, like copper, has a high annual rate of recovery—amounting to 44% of consumption. Half of the lead consumed each year is added to the lead-in-use resource, i.e. becomes available for recycling. In contrast to copper and lead, only 17% of zinc supply comes from scrap. Most of the zinc from old scrap (such as manufactured items discarded because of wear, damage, or obsolescence) is recovered in the form of die-castings, engravers’ plates, brass, and bronze, but this represents less than 5% of the total supply. New scrap, principally zinc-base and copper-base alloys from manufacturers, and drosses, from molten galvanizing and die-casting pots, contribute 10–15%. The large usage of zinc in galvanizing and in compounds (such as paints) where the zinc is lost is a major obstacle to improved recycling of zinc. Over the last 30 years, total annual consumption of ferrous scrap by the iron and steel industry has been close to a 1:1 ratio with virgin pig iron. Home scrap accounts for well over 60% of the scrap used in the steelmaking furnaces; less than 15% is prompt scrap, and the balance is obsolete material. Currently, the development of sophisticated processing and materials-handling equipment is revolutionizing major areas of the purchased-scrap industry. For example, giant shredders, or fragmentizers, with magnetic separators and pneumatic cleaning devices can convert up to 1,000 automobile bodies per day into scrap (i.e. at a rate of less than 30 seconds each). The combined national capacity of about 70 super-shredders and small-to-medium sized shredders in operation in 1968 was described as over 6 million tons, about equalling the tonnage of cars junked that year. Advances in balers, automatic shears, and conveyors contributed to the mechanization trend. Improved quality-control equipment permits the processor to deliver scrap material to more exacting specifications. In contrast with such changes, economically viable technologies for metals recovery from another major source—urban wastes—remain to be developed. Environmental Considerations: Environmental-quality requirements introduced over the past decade have significant impacts on the mineral industry. For instance, fumes from zinc smelters may contain cadmium, those from copper smelters may contain arsenic, and both operations generate sulfur dioxide.

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering FIGURE 7.2 DIAGRAMATIC FLOW OF INDUSTRIAL AND POST-CONSUMER SCRAP METAL

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.5 Recovery of Metals from Scrap as Related to Total Consumption, 1970 (Thousand Short Tons) Metal Secondary Recovery Total Consumption A\B, percent Aluminum 781 4,519 17 Copper 1,248 2,779 45 Iron 44,700 116,900 38 Lead 597 1,360 44 Zinc 260 1,572 17

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.24 Comparison of Material Cost* Material Cost per pound (cents) Density (lbs./cu.in.) Cost per cu.in. (cents) Steel 10 0.283 2.8 Aluminum 25 0.100 2.5 Zinc 20 0.236 4.7 ABS 30 0.038 1.1 Polypropylene 25 0.033 0.8 Polyvinyl chloride 28 0.045 1.3 * Approximate 1970 prices, intended for comparison purposes only.

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering 1975 this figure is expected to double. A tally of injection-molded plastics replacing metal would include such things as grilles, instrument panels, front-ends, fender extensions, fender liners, lamp housings, bezels, and valence panels. Besides plastics, other polymers are of major importance to the automotive industry, such as elastomers, paints, fabrics, adhesives, and sealers. Whereas a 1950 car used about 10 pounds of adhesives and sealants, today’s car carries about 70 pounds. In a typical full-size car of 1971, there were as many as 750 rubber parts in addition to the tires; these were made from 30 different rubber compounds. Since 1970 several significant milestones in nontire applications of rubber compounds have been achieved by the automobile industry. Some examples are elastomer tapes for bond-welding of large structural components, spray-on polyurethane bumper coatings, and the all-foam seats of polyurethane. Urethane coatings are being employed in production to coat elastomeric bumpers, instrument panels, and polycarbonate headlight bezels. Such coatings are ready for use on integral skin-foamed parts such as steering wheels, arm and head rests, visors, air scoops, and strip moldings. Urethane coatings also show promise for hoods, air foils, bumper guards, and fender extensions. The use of polyurethane foam is expanding faster than that of any other material in the automotive industry. More than 60% of all 1972 model cars had adopted the all-foam seat in favor of the once-dominant springs and padding. Penetration of plastics into the markets for steel, aluminum, and zinc is underscored by the differences in the growth-of-the-demand for these materials during the 1960’s. While plastics production increased over 150%, from 3 to 8 million tons, the 10-year increase in steel production was 33%, aluminum 60%, and zinc 25%. Some of the automotive products where this competition is important are listed in Table 7.25. Certain trends for plastics versus metals in the 1970’s are already evident. The average car in 1969 had approximately 100 pounds of zinc and 100 pounds of plastics. However, the use of zinc is expected to decline. Auto parts for which zinc and plastics compete include grilles, instrument panel assemblies, headlight and taillight housings, air-intake cowls, door glass channels, radio speakers, glove-box doors, bezels, trim components, etc. Usually the choice between plastics and zinc is settled by some secondary consideration such as appearance or style. The difficulty of plating plastics has favored zinc in some applications. In 1970, some automakers returned from plastics to zinc for rear-fender extensions, taillight assemblies, and headlight assemblies. Zinc is finding new automotive uses which cannot be challenged by plastics. In recent years, zinc has doubled the life of automobile leaf springs by acting as a sacrificial metal for corrosion. The continued development of plastic composite materials, especially those reinforced with glass fibers, hold even more promise for increasing the automotive uses of plastics. These materials form a unique bridge between the limitations of metals on the one hand and of unreinforced plastics on the other. Their favorable economics, rapidly advancing processing technology, and good mechanical performance assure their successful application in many areas which previously relied upon fabricated steel, die-cast metals, and expensive engineering thermoplastics. There have been more developments in glass-reinforced plastics in the five years of 1965–70 than in all the previous

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.25 Automotive Products That Can Be Made of Either Plastic or Metal Automotive Body Components Radiator Grilles Fuel Tanks Instrument Cluster Panels Front Seat-Back Trim Panel Wheelcovers Radiator Fan Shrouds Cowl Kick Panels Front Fender Skirts and Liners Seat Grid Liners Truck Trailer Liners Ductwork for Heating, Airconditioning Door Inner Panels and Locks Plated Trim, Decorative Medallions Control Handles and Knobs Bezels, Shelves, Mirror Supports Glove Compartment Arm Rests, Sun Visors

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering years since their introduction in the 1940’s. With new matched die-molding processes, for example, these materials may now compete with steel in large production runs of up to 70,000 units per year. Previously, even half that number could not be run. Current reinforced-plastics production of about one billion pounds per year seems small beside steel’s 250 billion pounds, plastic resin’s 19 billion, and aluminum’s 9 billion. However, a fourth of this business is already in ground-transportation markets, a sector where the high-strength, light-weight and good chemical resistance of reinforced plastics will make them increasingly attractive. Auto equipment is now the number two consumer of glass-reinforced plastics, after marine equipment, but will probably take over as the top user in the near future. Auto and truck applications alone were up 36% in 1971. In 1972 at least 250 different applications of glass reinforced plastics were used, compared to 200 different applications in 1971 and 110 in 1970. Car models in 1971 employed glass-reinforced plastics in 13 instrument panel assemblies compared to 8 in 1970. In 1972 model cars, there were 150 different applications of injection-molded glass-reinforced thermoplastics alone, compared to 92 in 1971 and 60 in 1970. In almost all cases, injection-molded reinforced thermoplastics now have strength and modulus values higher than die-cast zinc. A complex composite which can be injection molded for large automotive components, such as consoles, bucket-seat backs, and instrument panels, combined reinforced polystyrenes with fiberglass-reinforced styrene-acrylonitrile copolymer. Recently, a new glass-fiber-reinforced foamed plastic has become available; it is as strong as conventional reinforced plastic but weighs only 66% as much. Also, this fiber-reinforced foam can be injection molded. In addition, new processing techniques for reinforced thermoset plastics are improving these materials as candidates for automotive parts. Sheet-molding compounds were first introduced in 1969 in Chrysler station-wagon air deflectors. Usage has already spread, growing from 0.4 million pounds in 1969 to 10 million pounds in 1971, including front exterior panels, hoods, valence panels, window insert frames, and fender skirts. Large and complex pieces, having molded-in ribs, inserts, bosses, threads, and wide variations in thickness across the section, can be molded in one operation. If many of the one-piece sheet-molded front panels had been made of metal, they would have required six or seven pieces with as many as 20 forming and assembly operations. There has also been substantial growth in aluminum usage in the automotive industry. A versatile engineering material, aluminum alloys have seen increasing applications that take advantage of their high strength-to-weight ratio, impact resistance, corrosion resistance, and heat conductivity, competing with iron and steel. The lighter weight of aluminum in comparison to cast iron has led to its wider adoption in engines. One materials breakthrough is the production-die casting of hypereutectic aluminum-silicon alloy in engine blocks; this eliminates the use of ferrous cylinder-wall liners. Other structural applications of aluminum include wheels, brake drums, optional aluminum cabs on heavy trucks, and the use of high impact-strength aluminum alloys in experimental bumpers and safety vehicles built for the government. The corrosion resistance of aluminum has been used to advantage in chemically brightened or anodized alloys for such production items as

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering grilles, head-lamp bezels, and hubcaps. Its thermal conductivity puts aluminum in competition with copper and brass for automobile air-conditioning and radiator applications, and with iron as well for disk and drum brakes. One British-made aluminum radiator, for instance, is put together with adhesives and uses no fluxes. While aluminum is replacing cast iron, steel, and copper for some parts, lighter magnesium may also replace aluminum. One German-made car, for example uses die-cast magnesium in gearbox casings and engine crank-cases. All-in-all, 1970 automobiles had a record average of 78 pounds of aluminum, about a 6% gain over 1969 models. This was the fifth straight year of growing use of aluminum in U.S. cars, and a 50% gain over a decade ago. Developments in other materials than plastics and the light metals continue to be important in the automobile industry. Steels of recent vintage which have had large influence in the field include galvanized steels, whose automotive uses quintupled in the last decade; steels with other improved coatings and finishes, and higher-strength steels. HSLA steels (meaning “high-strength, low-alloy”) used in 1972 bumpers, for example, have yield strengths of about 45,000 psi, compared to about 30,000 psi for carbon steel bumpers. HSLA steels for side-impact beams are said to have a yield strength of 75,000 psi. Pre-painted and pre-primed steels also are becoming more readily available, and for some hard-to-form parts, pre-painted steels may be a better choice than even galvanized steel. Ceramic ferrites, usually pressed and sintered metal-oxide powders, are often improved substitutes for more expensive magnets in radios, small motors, and other electronic devices. Ferrites are now finding application in the small motors which raise and lower car windows, lock doors, and operate windshield washers. They are also used extensively in radios, a product for which automobile sets comprised 49% of the 1969 U.S. production. The competition among materials has also resulted in new composite materials which use, sometimes synergistically, the best qualities of each material. Thus, the first production bumper to withstand 4-mph barrier impacts without damage (1972 Saab 99-E model) took advantage of the properties of three materials—rubber, steel, and plastics. Under a thick rubber exterior coating, a U-shaped steel compartment holds energy-absorbing cellular plastic blocks. The role of processing technology has proved critical to production efficiency in the automobile industry. Metal casting, cold forming, and powder metallurgy are of growing significance in the industry and illustrate the impact, real and potential, of advancing metal-processing technology. For example, a new die-casting process along with a new aluminum alloy have been combined to produce the first all-aluminum engine. Also, a more ductile form of cast iron—nodular iron—has spurred ferrous-casting technology; lower-cost castings with at least equivalent performance are now supplanting parts that were previously forged. Similarly, greater uses of cold-forming processes and powdered-metal parts are resulting from interest in more efficient utilization of materials and reducing scrap. A cold-extrusion application has resulted in an 84% savings in materials over the previous machining process. One automaker has begun production of pole shoes for cranking motors in 1972, employing a new process that converts recycled metal scrap into fine powder.

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering Powder-metal compacting operations lend themselves naturally to process automation; now automatic presses achieve production rates of 500 to 1500 parts per hour or more. Few processes offer such precise control over materials and properties as does powder metallurgy. Frequently, no secondary-finishing operations are needed and powder-metal parts may be shipped directly following sintering. In the case of thermoplastics a relatively new development is injection molding using a reciprocating screw. Comparing two machines of similar size, a particular ram-injection unit processes some 80 lbs. of polystyrene per hour, whereas the screw unit processes 200 lbs. per hour. Moreover, materials which are otherwise very difficult to process can now be formed into intricate shapes and heavier moldings. Extrusion is used for forming rods, tubes, films, and shapes in a wide variety of profiles. An example of the extrusion process is in the fabrication of vinyl insulation on automotive electrical cable. Vacuum forming is widely used to shape the thermoplastic skin of dash pads before they are filled with polyurethane foam. Building Industry The building and construction industry is among the largest in the nation in terms of contribution to the Gross National Product, amounting to about $109 billion in 1971. As shown in Table 7.26, the total industry has doubled in scale over the past decade. Among the various sectors, buildings, in contrast with heavy construction such as dams and highways, account for the largest share (about 85%) of this total. The building industry has characteristics which make it quite unique, and therefore difficult to examine for a specific concern, such as innovation in materials technology, without some understanding of its complexities. In particular, markets are too small and heterogeneous for any standardized construction approach even in large production facilities, institutional structures, commercial buildings, and any special class of dwelling. Further, the different types of buildings are variously financed, built, marketed, and used. The industry has been described as composed of more than 90,000 contractors and 1,500,000 subcontractors employing 3,500,000 people. They are supplied by a myriad of other industries employing large numbers, such as the 240,000 employees of sawmills and planing mills, the 160,000 in millwork and related products, and the 260,000 who manufacture equipment. To handle financial, insurance, and real-estate dealings requires another 1,100,000 persons of whom more than 600,000 are in real estate alone. The building-design professions include 30,000 registered architects, and 75,000 engineers plus a number of specialists. The character of this industrial structure and distribution process exercises major influence on technology decisions. Materials constitute a relatively small part of the total costs of building development; land development, labor, and long-term financing costs are as, or more, important. However, in many instances, the intimate relationship of materials with people and function in buildings has psychological significance as well as physical, economic, and social requirements. Thus, there is real concern for improving materials durability, maintainability, utility, and their aesthetic effects. This concern increases the

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering TABLE 7.26 New Construction ($ Billions)   Total Residential Utilities Etc. Commercial Highways Educational Industrial Hospital 1960 53.9 22.7 5.4 4.2 5.4 3.4 2.9 1.0 1961 55.4 22.7 5.1 4.7 5.9 3.7 2.8 1.1 1962 60.0 25.2 5.1 5.1 6.4 3.6 2.8 1.3 1963 64.6 27.9 5.4 5.0 7.1 4.2 2.9 1.5 1964 67.4 28.0 5.7 5.4 7.1 4.5 3.6 1.8 1965 73.4 27.9 6.5 6.7 7.6 5.0 5.1 1.9 1966 76.0 25.7 7.5 6.9 8.4 6.3 6.7 2.0 1967 77.5 25.6 8.4 7.0 8.6 7.0 6.1 2.0 1968 86.6 30.6 9.7 7.8 9.3 7.0 6.0 2.3 1969 93.3 33.2 10.2 9.4 9.3 6.9 6.8 3.0 1970 94.3 31.7 12.1 9.8 10.0 6.5 6.5 3.4 1971 109.0 42.4 13.5 11.6 10.8 6.5 5.4 3.8 1972E 122.5 49.5 15.3 14.0 12.0 6.6 5.3 4.5 1976E 155.0 56.0 22.5 18.0 15.0 8.0 7.5 7.0

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering importance of materials to the marketability of the building, which offsets to a degree the relative insensitivity of materials technology in influencing the total cost. There are a few materials that are produced exclusively for building purposes, and many of the materials industries already discussed are the producers of either raw or processed materials for use in buildings. In addition, buildings contain subsystems—electrical, mechanical, and structural— whose basic material and components may have numerous nonbuilding uses as well. Consequently, the products and problems of other industries are inextricably intertwined with those in the construction industry. Further, the buildings embrace furniture, tools, machines, and other goods, and require an array of community services from waste handling to streets, earth-moving equipment, and soil stabilizers. In a larger sense, all of these involve materials and products which are part of the industrial system. Due to the highly competitive nature of the building market, walls, floors, partitions, mechanical and electrical subsystems, appliances, stairs, and other elements in buildings have been constructed of a wide variety of materials and combinations thereof, depending upon local building-code requirements, marketability, availability, and the impact of the selected materials on the total cost of the building. As new or improved appliances, fixtures, elevators, air-conditioning systems, structural and nonstructural systems are introduced for the first time, materials usage is directly affected. With almost every type of change—design, functional, technological, economic, ecological, social, legal, or political—materials usage is again influenced. Factors Affecting Materials Science and Technology: One of the most significant factors in the building industry has been the relatively rapid increase in the ratio between the cost of job-site labor and material cost. The percentage of material in the total “brick and mortar” cost has been decreasing: in multifamily-housing construction, for example, it is now less than 50%—reversing the previous historical relationship. It is believed that this reversal is also the case in many types of nonresidential construction, although detailed studies to establish historical trends are lacking. For some years, labor for all categories of construction have been rising at a rate about twice that of materials prices. While material price increases were reduced during the recent period of price controls, wage rates continued to climb. It is difficult to determine what portion of increased onsite-labor costs is due to higher “wages” and what portion is assignable to observed lower productivity. The issue of productivity in the industry has been recognized nationally as a major problem; it has been argued that low productivity, even more than high wages, may be pushing the cost of construction beyond the reach of many potential markets. This trend of increasing onsite labor cost has been largely responsible for the growing emphasis on the production of more and more building components and subsystems in the factory, with its present and traditional lower wage rate and more efficient production processes. For example, several companies produce modules for single-family homes and town houses, and also some of the major subsystems for multifamily housing. Factory-fabricated

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering subsystems and precast-concrete structural subsystems have been adopted for many years in nonresidential construction. However, the full potential of materials is not yet being realized in that for most factory-produced house modules, prefabricated structural components, or factory-built major subsystems, the basic materials of construction are not significantly different from those employed onsite to produce the same basic end facilities. Likewise, since materials may also lower onsite-labor costs, the potential of materials technology for achieving onsite productivity gains must be as much as in-factory gains. The relationship between labor and material prices is especially relevant in the context of total construction and development costs. For instance, approximately one-third of the total development costs for typical multifamily housing is accounted for in the aggregate cost of land, construction financing interest, cost of selling or renting the created units, legal fees, and other nonbrick-and-mortar items. In this case, it turns out that the price of materials is only one-third the total development cost. However, the choice and use of materials may also affect the speed of construction or the appeal to consumers, and this in turn affects the total price. For example, a 25% saving in overall construction time (a not-uncommon occurrence with the advent of new building technology) could save $170,000 in construction interest at 9% on a 10 million dollar project with a conventional 1.5-year cycle time. When a purchaser buys a house, apartment, or pays rent, the price of occupancy becomes an additional factor. Each year, there are the maintenance and operating costs and the cost of interest for permanent financing, with the exact amount depending upon interest rates, type of construction, fiscal needs of a community, and management practices. While materials per se are a small component of the total occupancy cost, the effect of materials technology can be quite significant. Thus, a relatively small outlay for a better appliance or material can lower maintenance and operating costs appreciably and increase value. As long as this added outlay does not substantially restrict the market—i.e., price a significant number of families out of housing—the value-added may be marketable. As a corollary, modernization of buildings is also a substantial activity affecting personal, business, and national economies. Materials Research and Development Emphasis: Information from building-product manufacturers reveals that the majority of their research and development effort is directed, not towards developing or exploiting new materials, but toward adapting the materials in which they have an established interest (i.e., a mining and/or manufacturing position) in order to lower installed costs, to reduce operating and maintenance costs, to combine function, to find new applications, or to provide comfort and safety. To reduce installed costs, such development programs seek to produce simplified methods of fastening, decrease product complexity, increase compatibility with interdependent subsystems, reduce number of parts needed for field assembly, and decrease material-handling and transportation costs. In these developments, individual materials, regardless of the principal reason for their selection in a given instance, tend to be viewed in the context of total system performance. In the area of operating and maintenance costs, long-term owners are recognizing

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering that costs over the term of proprietorship can decrease significantly if initial design-and-build decisions take into account time-dependent costs. Technology is increasingly expected to help reduce operating, replacement, and maintenance costs as well as first costs—a concept that is coming to be known as “life cycle costing.” Energy shortages are a factor increasingly affecting materials selection. Opportunities for conserving energy exist by controlling a host of variables, including window size, lighting levels, amount of outside air recirculated, design and operational characteristics of electrical equipment, utilization of insulation, and building orientation and geometry. Definitive quantitative analyses of the significance of all of these variables under a variety of conditions are still at an early stage of applicability. Fire safety and resistance to natural hazards and noise are being recognized as important areas for materials development. Fire-safety design is predicted in large measure upon contents of buildings, more popularly referred to as building “fire load.” Until recently, fire load data (as reported by the National Bureau of Standards) were based upon studies during the 1920’s and 1930’s; updating of such data merits high priority. Fire-safety practices include compartmentation; providing places of refuge; smoke-removal devices; smoke and heat detectors; communication systems; sprinklers, safety-exit planning; and elevator-emergency service. The development of needed criteria for fire-resistant construction materials requires acceleration to complement these practices. The foregoing discussion of cost factors in housing suggests that materials R&D will have little influence on the construction industry from the standpoint of materials costs. Thus, in the case of private homes, it is estimated that, on an average, the cost of the building is 33% of the purchase cost; land, 25%; and financing, 42%. Less than 50% of the cost of the building goes into the cost of materials; as a result, a 10% savings in materials amounts to less than 2% of the total cost of a home. Even industrialized housing, if it were technically practicable, is likely to do no more than keep building costs steady with present practices. Nevertheless, despite the small impact of direct materials costs, significant cost reductions could arise from increased efficiency in the processes by which materials are incorporated in the buildings, e.g., savings in the 42% labor costs associated with this step. Another important factor that will influence materials R&D for the industry in the future is the performance approach, as developed in particular by the Building Research Advisory Board of the National Research Council. The performance concept—involving criteria and specifications to meet them— has spawned a growing use of value engineering or consideration of alternatives during the design and procurement stages. This development increases the effectiveness of the competitive process over the traditional bidding among contractors against a fixed design material, or product specification. Most critically for materials, the role of the building-product producer is increased significantly in optimizing the structure through flexibility in materials performance and adaption to desirable processing modes. Finally, the issue of constraints peculiar to the building industry has significance for the role to be played by materials. The Committee on Urban Technology of the National Research Council, in its report on “Long Range

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Materials and Man’s Needs Materials Science and Engineering: Volume III The Institutional Framework for Materials Science and Engineering Planning for Urban Research and Development,” has pointed out that “a rewarding field in which to seek cost reduction lies in the identification and reduction of constraints imposed by tradition and present practice.” A detailed analysis of such problems by the Building Research Advisory Board identified the availability of materials as one of the constraints needing attention. While, the present study has reached a different conclusion regarding availability per se, it is clear that major constraints do exist due to high materials cost, performance limitations, and the ways in which materials are processed into construction products, components, subsystems and total systems. A key factor affecting materials in this respect is the currently limited viewpoint and policies of building-product manufacturers, particularly those with already established commitments to specific materials. Likewise constraining is the time required to develop an innovation to practice—on the order of five years. Hence, the cyclical character of the building industry and its sensitivity to many external influences tends to retard the exploitation of innovations. In another area, the movement toward doing more assembly work in the factory rather than onsite has introduced new factors, namely those associated with fixed costs of manufacturing. Consequently, increased automation and factory fabrication seem to have been occurring only in cases of intensive repetitive building where there is confidence in a continuing market large enough to permit amortizing the plant investment involved. It is clear that the fragmented character of the building industry is a severe obstacle in the extent to which major advances from materials performance and processing efficiency can be expected to be utilized. Materials and Standards Before a new material can be efficiently used in manufacturing and commerce, the properties and performance of the material must be described and specified. Both the functional value and the characteristics must be standardized if the new material is to be obtained competitively, and priced appropriately. The description of the desired characteristics of the material takes the form of a “standard specification,” which expresses the material characteristics in terms of quality, uniformity, and performance, in order to measure its ability to fulfill specific application requirements. For example, when a ton of structural steel is purchased for a specific price, the latter is related directly to a particular specification which stipulates the chemical composition (allowable limits on the amount of carbon, manganese, phosphorus, sulfur, silicon, and copper), the minimum allowable strength and ductility, etc. Thus, this standard specification defines the quality and therefore the value of the steel. In turn, to measure whether the steel meets these stipulations requires standard methods of test. Standards defined in this way are useful in every step of the manufacturing cycle—design, materials, processes, and product. Accordingly: Standards define the performance properties required by the user.