NATIONAL CONCERNS AND TECHNICAL CHALLENGES

Today we are faced with growing competition for nonrenewable raw materials and fuels and with low standards of living in much of the world. The latter is an old problem, but it is reemerging in a new setting that features prominently the aspirations of the developing countries, concern for the environment, and the scale of international human activities. These difficulties, in consequence, are attracting more and more attention, both in the U.S. and abroad, shifting to a degree the emphasis on national defense and political prestige toward more civilian-oriented goals and concerns.

Materials science and engineering can help meet the technical challenges of these growing concerns. The relationship between materials research and development and one such concern, health services, is shown in a general way in the partial “relevance tree” of Figure 9. The existing and potential utility of materials research and development in solving a range of other real-life problems will be evident in our discussion of opportunities in materials research (page 97). In addition, we have examined the diverse technical challenges of the country’s current concerns from two vantage points: challenges in the materials cycle, and challenges in specific areas of national concern, including a priority analysis based on questionnaire replies.

Challenges in the Materials Cycle

Materials science and engineering, by providing options at the various stages in the total materials cycle, can exert direct, if not



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Materials and Man's Needs: Materials Science and Engineering NATIONAL CONCERNS AND TECHNICAL CHALLENGES Today we are faced with growing competition for nonrenewable raw materials and fuels and with low standards of living in much of the world. The latter is an old problem, but it is reemerging in a new setting that features prominently the aspirations of the developing countries, concern for the environment, and the scale of international human activities. These difficulties, in consequence, are attracting more and more attention, both in the U.S. and abroad, shifting to a degree the emphasis on national defense and political prestige toward more civilian-oriented goals and concerns. Materials science and engineering can help meet the technical challenges of these growing concerns. The relationship between materials research and development and one such concern, health services, is shown in a general way in the partial “relevance tree” of Figure 9. The existing and potential utility of materials research and development in solving a range of other real-life problems will be evident in our discussion of opportunities in materials research (page 97). In addition, we have examined the diverse technical challenges of the country’s current concerns from two vantage points: challenges in the materials cycle, and challenges in specific areas of national concern, including a priority analysis based on questionnaire replies. Challenges in the Materials Cycle Materials science and engineering, by providing options at the various stages in the total materials cycle, can exert direct, if not

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Materials and Man's Needs: Materials Science and Engineering FIGURE 9 PARTIAL RELEVANCE TREE FOR HEALTH SERVICES The relevance tree shown here for health services and materials is not comprehensive, but illustrates the use of the technique for relating national or other broad goals to pertinent needs in research. Additional pathways between basic research and broad goals have been omitted for the sake of simplicity. Also omitted is the time scale: research on materials, for example, might not begin feeding information upward for 10 years or more.

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Materials and Man's Needs: Materials Science and Engineering always immediately visible, effects in the problem areas reflected by national concerns. It can help to slow and sometimes to halt the growth in demand for certain raw materials and fuels. It can help to move hardware technologies in directions that raise living standards at home and abroad. It can help to reduce deleterious effects on the environment to acceptable levels. And it can help to achieve these goals in a manner consistent with a sound U.S. balance of trade. Exploration. The sensing, information-processing, and transmitting functions of orbiting earth-resources satellites and lunar rovers were made possible by progress in development of electronic and structural materials. Comparable technology could be developed for exploring the ocean floor. For more traditional types of prospecting, instrumental methods should progress rapidly as more is learned of the “signatures” of complex natural materials. Mining. Ores and minerals, in the future, probably will have to be mined in more hostile environments at less accessible sites. (Manganese and other metals, as well as phosphates, for example, are available on the ocean floor.) Working conditions often may be impossible for human operators. To tap the resources available from ultradeep mines or below the ocean floor will require a new technology, “robotics.” In essense, robotics will involve solid-state electronic sensing and information-processing equipment coupled to servomechanical mechanisms that can operate under extreme conditions. The advent of novel equipment of this kind likewise will benefit conventional mining operations. Plasma and rocket-nozzle technology, for instance, has proved useful in

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Materials and Man's Needs: Materials Science and Engineering drilling the hard, iron-bearing taconite—which has largely succeeded the heavily depleted high-grade domestic iron ore that was long the mainstay of the nation’s steel industry. Extraction. We need very much to find new means of extracting basic materials from ores of progressively lower grade and from low-grade wastes, processes that are more efficient, that cost less, consume less energy, and cause less pollution. Aluminum already is being extracted from the abundant anorthosite (in the Soviet Union) as opposed to the conventional source, the high-grade but less plentiful bauxite. Under development in the United States are two new aluminum processes: one reduces by about a third the energy required to produce aluminum from alumina by electrolysis; the other produces aluminum in several (nonelectrolytic) steps, starting with various sources of the metal—not only bauxite, but low-grade alumina-bearing minerals and even clay. The large piles of blast-furnace and open-hearth slag in the Mid-west are potential sources of manganese and phosphate. Longer-range possibilities include simultaneous extraction—perhaps at very high temperature—of several materials from “ores” like granite, which contains all the elements necessary to a modern industrial society. For higher-value materials, study seems warranted on electrostatic, electrophoretic, and other novel methods of separation. Renewable Resources. Considerable scope exists for expanding the range of materials obtained from renewable resources. Wood and vegetable fibers might become important sources of primary organic chemicals, although they are not economically competitive today. Means of

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Materials and Man's Needs: Materials Science and Engineering “cracking” the lignin molecule, the binding material in trees, could make organic chemicals available from about 25 million tons of lignin disposed of annually in this country in wood wastes with only minor recovery of values. The utility of renewable resources in general might be extended by a variety of methods: better chemical means of recovering basic materials; control of physical properties by chemical or radiation treatment; genetic modification during growth; new ways to make composite materials of natural products; and improved methods of protecting and preserving structural materials made of natural products. Resource Substitution. The substitution of plentiful for less-plentiful resources is likely to become an especially important task for materials science and engineering in the future. A material may be substituted for another of the same class, as when aluminum replaces copper in electrical conductors, or for one of a different class, as when polyethylene replaces galvanized steel in buckets. We will need substitutes for certain metals that have unique and important properties but threaten to become critically scarce in the not-so-distant future. These include gold, mercury, and palladium. The nation’s balance of trade would benefit from substituting manganese for nickel as a stabilizer in stainless steels and substituting domestic ilmenite for imported rutile as a source of titanium. Even metals and alloys used widely in structural applications may offer broad scope for substitution by other alloys or ceramics based on substances more abundant in nature. The most common substance

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Materials and Man's Needs: Materials Science and Engineering in the earth’s crust is silicon dioxide. It is a basic constituent of glasses, which are remarkably versatile materials used hardly at all in proportion to their potential abundance. The properties of glass include excellent corrosion resistance and very high intrinsic strength. Aluminum and magnesium—though the energy cost of obtaining them is relatively high—are plentiful and display useful properties. These include, especially, the high ratios of strength to weight so important in engineering applications. Processing, Manufacturing. Widespread opportunity exists for new processing and manufacturing techniques that waste less material and use less energy than do current methods. More processes are needed that lead directly from liquids and powders to finished shapes, thereby avoiding, for metals, the ingot and hot-working states. Such processes in general cost less and consume less energy than do the cold-forming and machining required to shape bulk solids. Industry already shapes liquid or powders in many cases: manufacture of float glass, slip casting or compacting of intricate shapes, die casting and plastic molding, and hot forging of sintered metals. Continuous on-line assembly with minimum human intervention, a continuing objective for production lines, is virtually achieved in the manufacture of integrated circuits, where relatively few of the 200 or more processing steps are controlled actively by operators. The approach should be extended to other areas of processing and manufacturing. Some of the greatest savings in production costs and resources probably will result in the long run from greater use of small, on-line computers and robots. This form of robotics mentioned

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Materials and Man's Needs: Materials Science and Engineering earlier for mining calls for the imaginative exploitation of a variety of sensing and monitoring devices coupled through minicomputers to control mechanisms. Environmental Effects. The need to preserve the environment requires continuing development of industrial processes that release fewer harmful effluents or whose effluents can be captured and converted to harmless and preferably useful forms. Some such processes are used widely now. One is the recovery of sulfur from petroleum refinery off-gases. Another is the recycling of the hydrochloric acid that has been displacing the nonrecyclable sulfuric acid in the pickling of steel for cold-forming. The heavy, hard-rubber cases on automobile storage batteries are not reused and often are disposed of by burning; a lighter-weight, reusable plastic case would seem feasible. The metallic salts in polyvinyl chloride film may become an air-pollution hazard when the discarded film is burned, as in an incinerator; alternatives to the salts should be considered. To improve health and safety inside the plant, it is likely that one of the most effective moves will be a wider use of robotics where working conditions are not suitable for humans. Improved Performance. The purpose of materials science and engineering historically has been to improve performance by modifying existing materials and developing new ones. This activity will remain important. Demand will continue for higher-performance alloys, tougher glass and ceramics, stronger and tougher composites, greater magnetic strengths. But the task grows more complex as performance criteria come to embrace

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Materials and Man's Needs: Materials Science and Engineering chemical and biological as well as mechanical and physical properties. Consumers and legislation, furthermore, are calling increasingly for materials and products that are more durable, more reliable, safer, and less toxic. To meet these requirements, a number of complex, materials-related phenomena must be elucidated. They include corrosion, flammability, thermal and photodegradation, creep and fatigue, electromigration and electrochemical action, and biological behavior. Functional Substitution. Functional substitution offers great opportunity in materials science and engineering. The aim is not simply to replace one material with a better one, but to find a whole new way to do a job. To join two metals, for example, one can develop not just stronger nuts and bolts, but adhesives. Jet engines replace piston engines and propellers in aircarft; telephones replace the mails for transmitting information. Functional substitution can lead to the revision of consumption patterns for materials and energy and, indeed, can inspire the creation of entirely new industries. Widespread use of nuclear of solar energy could yield enormous savings in the transportation of fossil fuels. The transistor started the solid-state electronics industry, which has led to technologies like computers, missile-control systems, and a broad range of industrial, medical, and leisure products. Challenging problems for functional substitution include: developing materials and techniques for new methods of generating and storing electrical energy; and finding functional substitutes and biological materials to replace human organs.

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Materials and Man's Needs: Materials Science and Engineering Product Design. The better we understand the properties of materials and how to control them, the more efficiently we can design them into products, providing materials and design specialists work closely together from the beginning of the design and development process. The resulting interplay may change apparent design restrictions radically and achieve more effective solutions to the design problem. Purposeful blending of materials and design expertise, moreover, can contribute significantly to conservation of materials. Appropriate knowledge sometimes allows safety margins to be narrowed without hazard, thus reducing the weight of material needed in the product. Where properties like strength and elastic modulus can be upgraded, the product can be made, sometimes, to contain significantly less material without corresponding loss in performance. An example is the use of textured steel sheet in automobile bodies. Design can also be improved as a result of clarifying the functional requirements of specific parts of a product. If only a surface must resist corrosion, for example, coating or cladding may cost less—and may require less material—than use of corrosion-resistant material throughout. Recovery, Recycling. Facilitating the recovery and recycling of materials—apart from new approaches to questions like collection and separation—presents broad new problems in product design and materials selection. Product designs should ease dismantling and separation of components, but the rising costs of repair services tend to favor materials and products designed for replacement as whole units rather than for dismantling and repair. These conflicting

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Materials and Man's Needs: Materials Science and Engineering pressures will have to be reconciled. Metals like those in a shredded automobile tend to be degraded with each recycle, although they may be quite suitable for applications less demanding than the original ones. The same is true of blended plastics, ceramics, composites, and glass. It is not clear that these problems can be solved without sacrificing performance. We must learn not only to recycle materials more efficiently; we must develop secondary and tertiary outlets for recycled materials whose properties no longer meet the requirements of primary functions. Extractive chemistry and metallurgy will be important in improving recycling processes, but better physical methods of separation are needed, too. Materials Challenges in Areas of National Impact Peoples and nations have many kinds of concerns and goals. Some aspirations, like “Life, liberty and the pursuit of happiness,” are not truly reducible to tasks for science and technology. Others, like the desire for a strong domestic economy, clearly call for positive technical contributions. In connection with national concerns of the latter type, we have surveyed a number of specific challenges and priorities for materials science and engineering. One of our approaches involved a novel questionnaire on Priorities in the Field of Materials Science and Engineering. The questionnaire was designed to obtain both qualitative and quantitative opinions concerning important problems and specialties in materials research. It was sent to nearly 3,000 professionals representing many disciplines and responsibilities. The 555 usable replies were analyzed

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Materials and Man's Needs: Materials Science and Engineering in detail to yield, for each of the nine Areas of Impact, a selection of high-priority topics and specialties in applied and basic research in materials. The methodology and illustrative results appear in Appendix A. Among other questions, the respondents were asked to rate, on a five-level scale, the overall importance of materials science and engineering to progress in each of the nine Areas of Impact; some of the results, calculated as explained in Appendix A, appear in Table 13. No attempt was made to rank-order the relative importance of the nine Areas of Impact to the nation. The scope and nature of materials problems we have discerned in seven of the nine Areas of Impact are highlighted in the following brief descriptions.* Exhaustive treatments are beyond the intent of this summary report, though considerable additional information was obtained from the priority analysis (see Opportunities in Materials Research, page 97). Needs in Communications Society continues to demand communications systems of greater capacity, versatility, and reliability for many purposes: telephone; radio and television program distribution; information processing, storage, and retrieval; automatic billing, credit-checking, and other operations of a cashless society; airline and hotel reservations; police and fire departments; aircraft navigation and traffic control. *   These descriptions do not match precisely the Areas of Impact listed in Table 13. Materials problems in Defense, for example, are documented extensively elsewhere and so are not covered in the section on Space (page 68).

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Materials and Man's Needs: Materials Science and Engineering fibers are being studied for orthopedic service. A variety of membrane-fabrication techniques are being used, mainly with common materials, to improve the performance of economical oxygenator systems. And a new, still highly experimental use of biomaterials is in biologically active surgical implants. Enzymes bound to the surface of such an implant, for example, may catalyze specific biochemical reactions in the body. Needs in Environmental Management Many of the nation’s environmental problems reflect the customary inattention to the materials cycle. Industry, including the materials community, has tended, understandably, to optimize only that segment of the cycle that deals with the incoming material through to the out-going product, especially the parts of that segment where optimization will reduce costs. This approach creates environmental impacts that by now are well recognized. Few would question the need to broaden the span of materials management to the full cycle, from primary resources through disposal and reclamation, including the side effects such as emissions to the environment. Materials science and engineering can do much to ease the transition. Manufacturing. Knowledge of properties of materials can contribute to the development of manufacturing properties that generate less waste but preserve the functional properties of the materials involved. A general approach mentioned earlier is to shape products directly from fluid (liquid or powder) materials instead of from solids. A more specific example is the printed circuit board, which the electronics

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Materials and Man's Needs: Materials Science and Engineering industry makes from a board covered completely by a copper film. The film is etched away chemically to leave copper only along the desired circuit pathways. The process produces, industrywide, more than 5 million pounds per year of dissolved copper in wastes. Most of the metal is recovered, both because it is costly and because otherwise the wastes would present a severe disposal problem. New processes have been devised, however, in which copper is deposited in the first place only along the desired circuit pathways. The circuit pattern is first printed on the board with a special ink or with a polymer coating that can be optically activated and chemically developed in the shape of the pattern. The copper, deposited from a chemical bath, adheres only to the pattern delineated on the board. Both the ink and polymer processes avoid the waste problem and also reduce the costs of starting materials. Recycling. Materials scientists and engineers can create materials, or combinations of materials, that function as required and, at the same time, are amenable to product designs that facilitate recycling. An everyday instance is the glue used in some types of cardboard boxes. This adhesive gums up the paper-processing step so that the paper in the boxes cannot be recycled economically. Careful study of precisely how glue effects a bond, in terms of its composition and structure, almost certainly would yield an adhesive more compatible with reprocessing. Metals provide a second example. Some alloying substances and coatings degrade the base metal to the point where it cannot be recovered economically from the alloy. Similar problems exist with polymer blends. Materials research should create alternative materials systems that fill the design function at competitive cost and still permit economic reclamation.

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Materials and Man's Needs: Materials Science and Engineering Waste Conversion. Wastes can often be converted to useful materials, but the requirements of environmental protection and the related skewing of the traditional economic framework call for more concentrated effort. Examples of potential uses of wastes include the manufacture of brick from fly-ash or coal-ash slag combined with suitable binders. One new method of making brick combines almost any solid inorganic material with a small amount of portland cement and a proprietary chemical accelerator. The mixture is molded at high pressure to give a brick whose properties adapt it to new construction techniques that reduce labor costs. A waste of unusual potential is lignin, the cellulose-bonding material in wood. Lignin and other soluble components amount to some 55 percent of the weight of the tree. The lignin, about 25 million tons of it annually, is discarded with waste pulping liquor by paper producers. A small amount of lignin is recovered as lignosulfonates, which are used by industry as surface-active agents. An attractive possibility, however, is to employ lignin as a bonding agent in wood products, where it would function as it does in nature. The ability to use lignin in this way would represent a marked gain, both in conservation of resources and in environmental improvement, but the problem is particularly difficult. It has not responded to concerted scientific attack for some years. New hope lies currently in the use of sophisticated methods, such as high-voltage electron microscopy, to probe the chemical structure of lignin as it exists in the tree. Scientists to date have had to study the compound largely after it emerged from the severe chemical attack of the pulping process.

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Materials and Man's Needs: Materials Science and Engineering Organic wastes might provide a raw-material base for biodegradable plastics, although the costs involved are quite unfavorable today contrasted with plastics made from petroleum and natural-gas liquids. Newsprint and waste cotton fabric might be recycled to become a raw-material base for cellulosic plastics. Ethylene, the leading monomer for plastics today, might be manufactured by fermenting sugars or hydrolyzed cellulose to ethyl alcohol, which could be cracked to ethylene. Packaging. Noteworthy among environmental concerns are packaging materials. Consider the simple beer can, a common element of litter. For economic reasons, producers have shifted from iron-based cans, which rust away eventually, to aluminum cans, which last almost indefinitely. A container material that degrades quickly and naturally could solve the litter problem. It might be costly, on the other hand, and be made from a relatively limited resource like petroleum. Iron or aluminum can be reclaimed without great difficulty, if at some cost, and reclamation is perhaps the pragmatic course at the moment. In any event, the packaging problem illustrates an environmental role of materials science and engineering applied to the materials cycle. Needs in Housing The materials-related problems in housing, even those of broad import, hamper progress much less than do legal, economic, and cultural constraints. Easing these constraints was one of the goals of Operation Breakthrough, sponsored by the Department of Housing and Urban Development (HUD). An official of HUD has said of Breakthrough,

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Materials and Man's Needs: Materials Science and Engineering “…very little of what we are doing involves basic research or totally new hardware technology.” HUD hoped to “…facilitate the…use of technology which currently exists but has not found extensive use by the housing industry.” Predicting Behavior. A major bar to the introduction of new materials in housing is the unreliability of short-term tests for predicting long-term behavior such as weathering. A related obstacle is the lack of data on the performance of materials and components in service. Information is scattered and uncorrelated; a sound compilation is not available to the housing industry. Such data are basic, not only to the use of current materials but for developing short-term tests and otherwise predicting the behavior of new materials. A second general need is a more fundamental basis for predicting the effects of fires in buildings. Laboratory tests have been devised to measure such parameters as speed of ignition, rate of flame spread, smoke evolution, and penetration of fire through walls and partitions, but the validity of these empirical tests is too uncertain. Their frequent appearance in building codes is due largely to the lack of anything better. The peculiar needs of flammability research could be well served by a center devoted to this subject. Performance Criteria. The estimated 4,000–6,000 building codes in this country impede progress partly because they are out of date and more importantly because they differ among themselves. The resulting effects are to limit both the range of usable materials and the size of their markets; both factors restrict the effort likely to be expended

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Materials and Man's Needs: Materials Science and Engineering on new materials. The probable solution is to replace building codes with performance criteria. Such criteria would specify degrees of safety, durability, livability, and the like, but would leave design and materials selection to the engineer. (The National Bureau of Standards developed “guide criteria” in the course of its evaluation of the 22 housing prototypes created by industry under Operation Breakthrough.) Replacement of building codes by performance criteria is expected eventually to permit the development of modular home-building systems. These could consist of standard components, assembled offsite into a variety of configurations. Offsite manufacture will reduce costs, but perhaps by no more than 20 percent of the cost of the home, including land, financing, and so forth. Performance criteria and testing, however, will help resolve other problems: protecting the public against poorly designed and unsafe structures; establishing standards of construction suitable for Federal Housing Administration mortgages; and developing more livable communities of homes. Thermal Insulation. The National Bureau of Standards has estimated that energy consumed in residential heating and air conditioning could be reduced, nationwide, by as much as 50 percent from current levels by better insulation and construction. The technology is available, and insulation is being upgraded. Offsite Assembly. Developments in housing materials will come most likely in response to demands of industrialized offsite assembly processes. A number of laboratories, for example, are seeking materials capable of

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Materials and Man's Needs: Materials Science and Engineering joining housing components satisfactorily for long-term service. Other problems include the fire-retardation properties of synthetics, which generally will have to be less expensive before the materials can enjoy widespread adoption in housing. Materials such as gypsum board, plywood, concrete, glass, and aluminum, on the other hand, are remarkably inexpensive and unlikely to be displaced soon in their traditional functions. The persistence of familiar housing materials is evident in the mobile home industry. Mobile homes are made in sufficient volume—the number sold in 1972 amounted to 20–25 percent of the housing starts that year—to be well adapted to industrialized assembly. They are not subject to building codes, moreover, and thus offer unusual flexibility in materials selection and assembly techniques. Even so, the industry has not seen the emergence of spectacular new families of materials. Aluminum sheet, hardboard, and the like are in common use. More advanced concepts are found perhaps in bathroom materials, where the traditional cast iron and porcelain have given way largely to reinforced plastics. These are mainly glass-fiber reinforced polyesters with gel coats. They are light and strong and withstand the handling involved in assembly and transportation. On the other hand, they scratch more readily than porcelain, and are subject to cigarette stains and charring although they meet fire safety requirements. New building materials have appeared in recent years, of course, for applications other than in mobile homes. Prominent among them are polymeric products such as vinyl tile, polymer-paper laminates for

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Materials and Man's Needs: Materials Science and Engineering working surfaces, and sealants and gaskets for installing large sheets of glass and prefabricated components. A product specifically of materials science and engineering, polymer latex-modified portland cement, has experienced modest but growing success in the decade it has been on the market, despite its relatively high cost. More recently, a high-strength concrete reinforced with steel or glass fibers has been developed. These newer materials have succeeded as a rule by producing economies, as in assembly or maintenance, that offset their higher initial costs. And since the greatest economies in housing probably will stem from offsite assembly, novel materials seem likely to be tied to that method of construction. Needs in Consumer Goods, Production Equipment, Automation In addition to the preceding illustrative studies of materials in seven areas of impact, we have analyzed the qualitative responses to the COSMAT priorities questionnaire in terms of specific research needs in all nine of the areas surveyed. In consumer goods and production equipment, the two areas not covered above, the responses mentioned certain requirements consistently. These include, for consumer goods, greater durability (both physical and chemical), less flammability, and greater safety, reliability, serviceability, and maintainability. A clear need exists also for better tests for these characteristics. Materials problems mentioned consistently for production equipment include longer-lasting, higher-speed machining devices, both metallic and ceramic (e.g., grinding wheels), better joining methods, and greater high-temperature strength.

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Materials and Man's Needs: Materials Science and Engineering We have noted earlier the attractive opportunities in a special area of production equipment: automation and robotics. These opportunities exist not only in production and manufacturing, but also throughout the service areas of the economy—mail sorting, billing, typesetting, weather forecasting, health checkups, traffic control. Automation techniques in all of these areas include a common approach: the generation and processing of information to provide or display data in useful forms or to control servomechanisms. Myriad opportunities can be discerned in primary information-generating devices or sensors, which will depend on the nature of the quantity or physical property to be measured, the object to be sensed, or the pattern to be diagnosed. Nearly always these sensing techniques must be nondestructive. They must rely, therefore, on the effects of the interaction of matter with various kinds of radiation—optical, electromagnetic, ultrasonic, and others. Progress in this field clearly will require the most sophisticated knowledge of materials and of spectroscopy in its broadest sense. The signals generated by the primary sensing device usually must be processed, analyzed, and correlated by a computer or, increasingly, a mini-computer, itself a product of sophisticated materials science and engineering in its integral circuits and memory devices. Once in useful form, the information can be printed out, visually displayed, or used to control a machine or servomechanism. Opportunities for improvement lie both in visual displays and in computer-controlled machines. The latter can range from simple mechanical transducers—to control a valve, for example—to complex robots that can simulate some of the routine actions of human beings.

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Materials and Man's Needs: Materials Science and Engineering The development of this type of automation will require new devices, particularly optoelectronic ones, and solid-state electronic circuits with associative memory and learning capability for parallel processing. Especially promising avenues for further research appear to be semiconductor lasers and light-emitting diodes, magnetic-bubble devices, charge-coupled devices, reversible photosensitive materials, liquid crystals, optical modulators and deflectors, and various functional components such as amplifiers, timing circuits, and shift registers. Advances in servomechanism design will call for the combined talents of electrical and mechanical engineers, but often these devices and machines will also place stringent demands on the materials of which they are made, especially when the equipment must work reliably for long periods in hostile environments. Automation is a very broad interdisciplinary area and is likely to become more so. It combines the knowledge and skills of materials scientists and engineers with those of the information community— mathematicians and statisticians, as well as computer hardware and software engineers. The economic and social implications of switching to automation in a given operation, moreover, can call also for the expertise of economists and social scientists. Goal-Oriented Materials Research Bearing on Areas of National Impact COSMAT analyzed several thousand write-in comments from materials professionals to derive a list of goal-oriented research topics that rate high priority in the nine national areas of impact. The topics selected included various properties of materials, classes of materials, processes, and applications (Table 14).

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Materials and Man's Needs: Materials Science and Engineering TABLE 14 Goal-Oriented Materials Research Bearing on Areas of National Impact Analysis of several thousand write-in comments from materials professionals indicates that the topics below rate high priority in research in the areas of impact shown. Where applications are listed, the meaning, generally, is that new materials and processes are needed to advance the application. Communications, Computers, and Control Memories; visual displays, semiconductors, thin films; integrated circuit processes, yields in large-scale integration, component reliability; optical communication systems; defect properties of crystals; chemical and surface properties of electronic materials; purification; crystal growth and epitaxy; joining techniques; contacts; high-temperature semiconductors. Consumer Goods Durability; visual displays; corrosion; mechanical properties; improved strength-to-weight packaging; recyclable containers; high-strength glass; plastics; plastic processing; composites. Defense and Space Mechanical properties; lasers and optical devices; energy sources; heat resistance; corrosion; radiation-damage-resistant electronics; composites; turbine blades; heat shields; thermal-control coatings; nondestructive testing; higher strength-to-weight-ratio materials; reliability; materials for deep-sea vehicles; joining. Energy Battery electrodes; solid-state electrolytes; seals; superconductors; electrical insulators; mechanical properties; radiation damage; high-temperature materials; corrosion; joining; nondestructive testing. Environmental Quality Less-polluting materials processes; pollution standards; recyclability; reduced safety and health hazards; extraction processes; catalysts; secondary uses for discarded materials; sorting processes; nondestructive testing; noise reduction. Health Services Implant materials; membranes; biocompatibility; medical sensors; material degradation. Housing and Other Construction Prefabrication techniques; corrosion; cement and concrete; weatherability; flammability. Production Equipment Friction and wear; corrosion; sensors; automation. Transportation Equipment Corrosion; pollution control; high strength-to-weight ratios; high-strength, high-temperature materials; impact resistance; catalysts; adhesives; superconductors; lubricants.