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.

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.

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 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. To control such pollutants within acceptance limits requires add-on equipment to remove them or even changes in the technology of the extraction processes themselves. Thus, in order to assist in minimizing the release of such pollutants, there is a need to improve the methods of recovery of “associated” metals (e.g. bismuth antimony, rhenium, cadmium, indium, and others) that occur with copper, lead, and zinc ores. Ordinarily, these associated metals are present in such small amounts that they are disregarded in commercial smelting operations.

In addition to problems in processing, the actual utilization of some metals is being reduced because of environmental concern. Examples are the curtailed demand for mercury and the decrease in the demand for lead as automobile fuel is switched away from leaded gasoline. Conversely, demand for other metals is likely to increase due to construction requirements for pollution-control equipment. One specific example is the expected increase in demand for platinum in automobile catalytic mufflers to meet the requirements of the Clean Air Act of 1970. Correspondingly, petroleum refineries may need more platinum for catalysts as demand for lead-free gasoline is increased.

The following summarizes the capital expenditures expected in the various metal industries to comply with environmental regulations over the next several years. To control air and water pollution associated with the smelting and refining of aluminum, an investment of $935 million will be required for the period 1972 through 1976. Annual costs are estimated to range from $22 million in 1972 to approximately $290 million in 1976. Cost increases per pound of aluminum in 1976 may average $0.020 to $0.032. ² For copper, control of smelter stack-gas emissions is the most pressing problem facing the U.S. industry. Estimated capital investment for air- and water-pollution controls required of the copper industry between 1972 and 1976 is expected to total $300 million to $690 million, with a most likely estimate of $340 million. Annual costs are estimated to increase from $6 million in 1972 to $95 million in 1976. Per pound of refined copper, these costs would average $0.001 in 1972 and $0.025 in 1976, with a possible high estimate of $0.05 in 1976. ²

For lead, the total capital expenditure required to control the pollution associated with smelting and refining, might be about $70 million for the 1972 to 1976 period, with annual costs increasing from $1.1 million in 1972 to $20 million in 1976. Costs per pound of lead in 1976 have been estimated at $0.012 to $0.017. ² However, these studies did not consider the substantial changes in the lead markets that might be caused by other pollution abatement regulations such as those to reduce the lead content of gasoline. For zinc smelting and refining, $62 million of capital expenditures are estimated for the period 1972 to 1976. Annual pollution-control costs may increase from $1.5 million in 1972 to $27 million in 1976, averaging $0.0123 to $0.0267 per pound of zinc, with an expected cost of $0.0135 per pound. ²

Demand for inorganic nonmetallic materials accounted for 8% of total mineral tonnage in 1950, an estimated 8% in 1971, and is projected to be 11% in 2000. These materials include a wide range of substances, from large-bulk items such as sand, gravel, stone, and clay, through intermediate processed materials such as ceramics, electronic crystals, and synthetic high-hardness abrasives. In general, they are produced in response to near-term demand, and domestic reserves for most major nometallics are large. Domestic mineral production of nonmetallics in 1971 was valued at $5.9 billion. The corresponding variety of materials is shown in Table 7.6. Many are large tonnage items, of initial low value in the unprocessed stage, but acquiring substantial added value in the form of glass, ceramics, chemicals, etc.

Nonmetal mining or industrial-minerals operations tend to be diverse in size and degree of integration. In general, the abundance of these items is such that there is no reclaimed material production. For the most part, the secondary or reclamation segment of the nonmetallic minerals industry is limited to some reclaimed fluorine, diamonds, and abrasives. Pollution-control regulations may force an increase in recycling but high transportation costs are likely to limit the size and market for such operations.

In the following, attention is given to some of the major categories of materials involved in order to illustrate the principal features of the industry. The categories are ceramics, construction materials, fertilizer minerals, and a selection of the other major nonmetallic materials.

Ceramic Materials: The technology of ceramic materials may be divided into two major categories. One branch produces large quantities of relatively simple products which in total play a significant role in the U.S. economy: cement, brick, tile, glass, whiteware, refractories, clay products, etc. The technology of these materials has, in general, kept pace with needs. In recent years, however, the float process for flat glass came from abroad, and glass imports have been sufficiently large to cause some problems for the domestic industry. Another branch of ceramics is more closely allied to the frontiers of materials science, solid-state physics, and solid-state chemistry. This branch has developed the transistor, synthetic diamonds, luminescent phosphors, and high-temperature oxides, carbides, nitrides, borides, etc. Nuclear fuels are an important development of this activity. These specialized materials require the application of scientific thinking and practices, and have resulted in the establishment of whole new industries. However, continued progress in the science of such materials is dependent upon further extensive research of the most fundamental nature and the interchange of information among widely differing scientific disciplines.

Shipments of products from the ceramic industry which totalled some $15 million in 1972 are important inputs into the construction, container, auto, lamp, and electronics industries discussed in other sections of this chapter. In addition, nuclear fuels, refractories, carbon, and graphite are important components of energy supplies, containment, and use. Materials listed in Table 7.7 illustrate the wide variety of essential ceramic products and the industries to which they contribute. Figures 7.3 through 7.6 show the different growth characteristics of some of the principal ceramic materials and products since the early 1960’s.

Construction Materials: Figure 7.7 shows that the use of nonmetallics in construction has more than tripled over the past two decades. These materials are produced almost wholly within the U.S. and imports are negligible. Further, except for the reuse of some old brick, and of building rubble as construction fill, recycling is not a factor. It is apparent that there have been steady and roughly proportionate increases in the use of cement, stone, and sand and gravel; these substances are commonly mixed together in specific proportions to make the heavy construction material for foundations, bridges, buildings, airports, roads, dams, etc. The consumption of clay and gypsum has increased slightly in recent years; clay is used to make a variety of products such as tile, pipe, and ceramics for construction, and gypsum is used to make plaster board which is in wide demand for its insulating and fire-retardant properties.

Fertilizer Materials: Figure 7.8 shows the rise in the U.S. use of the three major fertilizer ingredients—nitrogen, phosphorus, and potassium (N-P-K). The major increase in domestic agricultural productivity since World War II has resulted, in significant degree, from the intensive application of N-P-K, and other trace elements. Figure 7.8 also shows that exports of phosphate rock have provided a substantial market for the domestic phosphate mines, and indicates the increasing role of potash imports in the past several years.

Other Nonmetallic Minerals: Other nonmetallic minerals of importance to the U.S. economy include asbestos, barium, boron, bromine, calcium, corundum, diamonds, diatomite, emery, feldspar, fluorine, garnet, graphite, gypsum, kyanite, lithium, mica, perlite, pumice, quartz, sodium, strontium, sulfur, talc, soapstone, pyrophyllite, and vermiculite.

Asbestos demand is expected to increase domestically at an annual rate of 2.7 to 3.5% over the next few years. The worldwide shortage once predicted for the mid-70’s may be alleviated by the regulation of its use because of toxicity. Substitutes for asbestos are being sought for many applications. Currently, about 70% of asbestos consumption is in the cement products and construction field where the fibers are reinforcing agents. Other uses are: floor tile (10%), paper products (7%), transportation products (3%), textiles (2%), paints and caulking (2%), and plastics industries (1%). Nine companies produced all of the asbestos in the U.S. in 1970. Fully integrated companies, which are producer, consumer and end-product retailer, are common in this industry.

Barite demand is forecast to increase domestically at an annual rate of 1%. The U.S. is the world’s largest consumer, and while it produces about 20% of the world output, it is still a large importer. The major use for barite is as a weighting agent in oil- and gas-well drilling muds; this accounted for 79% of the 1970 consumption. The manufacture of barium chemicals takes up 10% of barite consumption. Most of the remaining 11% is used as a flux, oxidizer, and decolorizer in producing glass, and as a filler in paint and rubber. Four companies accounted for 69%, and 10 companies for 93% of the 1970 mine output, which was valued at $854,000.

Boron demand is expected to increase at an annual rate of 3 to 4%. For the next twenty years or more, these increased needs are expected to be met largely by expanded domestic production. Important uses of boron compounds are in the manufacture of starch adhesives, ceramics, paints, soaps and detergents, fiberglass, flameproofing, gasoline additives, electrolytic condensers, glass, leather tanning, nonferrous-metal refining, nuclear-reactor control rods, photographic chemicals, and porcelain enamels. Boron compounds are also used in fungus control, herbicides, and agriculture. Glass and glass-ware accounted for about 42% of total U.S. consumption of boron; vitreous enamel and paints, 10%; soaps, cleansers, and detergents, 16%; fertilizers, 5%; and other uses, 27%.

Clay demand is forecast to increase at an annual rate of 3.5% and will be met by expanded domestic production. Reserves are plentiful and few problems of supply are expected. Imports declined nearly 25% to an all-time low of 64,000 short tons in recent years. Clay uses are many and varied, and sources are widely distributed throughout the country. Principal applications in 1970 were: structural clay products, 40%; hydraulic cement, 21%; and expanded clay, 18%. Other important markets were iron-ore processing, paper mills, and nonferrous metals.

Clay was produced at 1,457 mines in 1970, in all States except Alaska and Rhode Island. Brick plants and cement mills are scattered all over the country. Specialty clays such as ball clay, bentonite, fuller’s earth, and kaolin, are produced in localized areas and are shipped throughout the country.

Corundum demand is forecast to decrease domestically at an annual rate of 2%. U.S. requirements, which were met by imports from Southern Rhodesia until trade was stopped because of U.N. sanctions, have been supplied since 1969 from industry and government inventories. A single U.S. company acquired the entire surplus of corundum after the stockpile objective was reduced to zero and this supply was authorized for disposal.

Emery demand is forecast to increase domestically at an annual rate of 3%. However, the number of producers in New York, where the only commercial deposits of emery are found, has decreased to one; and zoning restrictions may close the remaining one. Corundum in its grain or powder form is used as an abrasive for lens grinding, (45%); pressure blasting of fabricated metals (40%); and other uses (15%). Emery is used primarily in the U.S. for nonskid concrete floors (45%), on highways (30%), and other miscellaneous abrasive applications (25%) which include coated abrasives, bonded products, polishing grain, and pressure blasting. One company in Massachusetts is the sole importer, processor, and distributor of corundum abrasives in the U.S. A New York company is the sole emery producer in the U.S.

Industrial diamond demand is forecast to increase domestically at an annual rate of 4 to 5.5%. Much of the increased need can be met by domestic manufactured synthetic diamond (25 mesh or finer). The U.S. has no domestic resources of natural diamond. The principal uses are in dies, grinding wheels, bits, tools, and in lapping and polishing compounds. The principal markets are in the manufacture of transportation equipment, 21%; electrical, 16%; concrete construction, 11%; exploration, 9%; dimension stone, 7%; stone, clay and glass, 4%; and all other uses, 15%.

Diatomite demand is expected to increase domestically at an annual growth rate of about 5%, and can be met by increasing production from existing open-pit operations in the Western States. In 1970, industrial and and municipal water, food, beverage, and pharmaceutical processing required 58% of the diatomite production; industrial chemicals, 19%; thermal insulation, 4%; and other, 19%. During 1970, nine companies operating 11 plants principally produced and prepared all the domestic diatomite valued at $32.6 million.

Feldspar demand is forecast to increase domestically at an annual rate of 3.4 to 5.8%. These needs can be met by increasing production capacity through more than adequate reserves. (Note: Since a high percentage of feldspar supply is consumed in the manufacture of disposable bottles, legislation regulating their use may significantly alter the market for feldspar.) Feldspar is used in glassmaking to increase workability and chemical stability. Applications are for container glass, 44%; flat glass, 11%; ceramics (principally as a flux), and pottery making, 36%; enameling, 2%; and other uses such as abrasives, scouring soap, fillers, welding-rod coatings, 7%. Three firms accounted for 62%, and 7 firms accounted for 90% of 1970 mine production of the domestic feldspar (650,000 tons total).

Fluorspar demand is forecast to increase domestically at an annual rate of 3.6 to 4.6%, a rate which is faster than the probable domestic supply. In the near future, the importation of fluorspar is expected to continue at current or increasing rates. About 36% of the fluorspar consumed in the U.S. is used in the fluorocarbon industry; 40% in the steel industry; 21% in the aluminum industry; and the remaining 3% in miscellaneous electrometallurgical, chemical, ceramic, and other industries. In 1971, 2 large companies and 13 small companies operated 27 mines in 9 states. Fluorspar ores are concentrated in heavy-media and/or flotation plants. In 1971, U.S. companies produced finished fluorspar having a total value of $17 million.

Garnet demand is forecast to increase domestically at an annual rate of 2.1% for abrasive quality and 4.7% for sandblast quality. The increased needs are expected to be met by expanded domestic production. Uses for garnet are: grinding and polishing flat glass and optical glass, 32%; aircraft, 28%; other transportation, 10%; wood furniture, 10%; plastic products, 6%; semiconductors, 6%; fabricated leather products, 5%; and miscellaneous, 3%. In these applications, garnet competes with other natural and artificial abrasives. One company produces all the abrasive-quality garnet in the U.S. and accounts for all U.S. exports. Three other companies produce sandblast quality.

Graphite demand is forecast to increase domestically at an annual rate of 1 to 2% based on 1969 consumption of 61,000 tons. The increased needs are expected to be largely met, for the short term, by expanded imports. Nationalization of the Ceylonese mines has created uncertainty about future U.S. supplies from there. In 1970, natural graphite was used for foundry facing, 33%; crucibles, 9%; other refractories, 15%; a carbon raiser in steelmaking, 10%; dry lubricants, 10%; pencil leads, 4%; batteries, 3%; truck and bus brake linings, 3%; and other uses, 13%. Two hundred and thirty-five manufacturing plants account for an estimated 65% of graphite. Many small firms consume the rest. Primary metals use 43%; stone, clay, and glass products, 26%; nonpetroleum lubricants, 10%; pencils, 4%; and other uses, 17%.

Kyanite demand is predicted to increase domestically at an average rate of 3.8 to 6.7% annually. This rate could decline substantially if the direct reduction process for steel production becomes commercially feasible. More complete recovery and use of byproducts such as pyrite, silica, and flake mica should be feasible with future advances in technology. The U.S., already the world’s largest producer of kyanite and synthetic mullite, could become the largest exporter of these commodities. Nearly 90% of the 1970 consumption of kyanite and mullite was for refractories employed in the production of iron, steel, glass, ceramics, and nonferrous metals. Three firms, each with combined mining and processing facilities, supplied 100% of marketable production in 1971. Synthetic mullite was produced in 1970 by 7 firms.

Mica scrap and flake demand is forecast to increase domestically at an annual rate of about 4.5%. Increasing demand can be met from several domestic resources which are amenable to economic benefication techniques. Although foreign producers will endeavor to increase their future scrap exports to the U.S., domestic production should remain competitive. Good quality scrap mica is delaminated and fabricated into mica paper for the electronic and electrical industries. The remaining scrap and flake is processed into ground mica for various industrial end uses, with a significant quantity of good quality scrap being delaminated for fabrication into reconstituted mica products. In 1970, scrap and flake mica were processed by 20 companies operating 22 grinding plants in 14 states. End uses for ground mica were: mica paper, 4%; gypsum plasterboard cement, 30%; roofing, 25%; paint pigment extender, 22%; molded rubber products, 6%; and other miscellaneous items, 13%. There are approximately 20 flake mica producers in the U.S. The 1970 flake mica production was valued at $2.5 million.

Mica sheet, consisting of block, film, and splittings is expected to decline in demand domestically at an average rate of 8% annually, because of the substitution impact of solid-state electronics and the availability of suitable alternate materials, both mica and nonmica based. Sheet mica is used in the manufacture of vacuum tubes, capacitors, and other electrical and nonelectrical items. Muscovite block and film was consumed by 17 companies in 8 states during 1970. Splittings were fabricated into built-up mica products by 13 companies in 9 states. Six companies accounted for almost four-fifths of total consumption.

Perlite demand is forecast to increase domestically at an annual rate of 3 to 4%. No immediate raw-material source problem is seen. Further growth in consumption is likely to be proportional to the rate of building construction. Expanded perlite is consumed as follows: aggregates (plaster, concrete, and insulating board), 59%; industrial water, food, beverage, and pharmaceutical processing, 23%; thermal insulation, 3%; agriculture, 4%; and other uses, 11%. Crude perlite was produced by 12 companies at 14 mines in 7 states. The value of crude perlite sold and used to make expanded material in 1970 was $4.9 million; the value of expanded perlite sold and used by 89 plants in 33 states was nearly $25 million.

Natural quartz crystal demand is predicted to increase domestically at a maximum annual growth rate of 0.25%. Substitution of synthetic manufactured quartz for natural quartz has lowered U.S. dependence on Brazilian imports. Practically all electronic-grade natural quartz is processed into finished crystals for electronic frequency-control or selection equipment. A very small quantity is used for prisms, wedges, lenses, and other optical purposes. Raw quartz crystal in 1970 was consumed by 26 cutters in 12 states. Quartz crystal is used in the manufacture of oscillator plates, 73%; filter plates, 18%; telephone resonator plates, 8%; and other miscellaneous items, 1%.

Sodium carbonate or soda ash demand is expected to grow at an annual rate of about 4%. In the past, most soda ash has been produced from salt by the solvay process, but an increasing quantity (41% in 1971) is being produced from natural sources of sodium carbonate. New soda ash production facilities are dependent entirely on natural sodium carbonate minerals rather than salt. Some solvay plants have been ordered to close because their effluent could not meet new standards set by environmental protection authorities. Of the total sodium carbonate produced in the U.S., about 50% was consumed in the manufacture of glass, and 40% in the production of other chemicals. The processing of wood pulp into paper required 8%, and the remainder was consumed in soap, detergents, and other uses. Sodium carbonate is derived from natural sources by four companies. Five companies produce sodium carbonate from salt.

Sodium sulfate demand is expected to increase at an annual rate of 4%. In 1971, 46% of domestic output came from natural sources and the remainder was produced by byproducts from salt and sulfur compounds in manufacturing rayon, cellophane, and other commodities. Sodium sulfate is used in the production of kraft paper (74%) and in other miscellaneous products such as glass, ceramic glazes, detergents, stock feeds, dyes, textiles, medicines, and other chemicals. In 1971 natural sodium sulfate was produced by six companies, valued at $12.6 million.

Talc-group minerals demand is forecast to grow at between 2.5 and 4.6% annually. Domestic resources will be more than adequate to meet domestic needs. Talc and soapstone uses in 1970, in order of importance, were: ceramics, 27%; paint, 18%; paper, 6%; roofing, 5%; insecticides, 4%; rubber, 3%; toilet preparations, 2%; textiles, 1%, and other products, 34%. Talc, soapstone, and pyrophyllite are consumed by many firms in all parts of the country. Uses by industry in 1970 were: stone, clay and glass products, 34%; chemicals, 29%; paper, 6%; asphalt, 4%; rubber, 3%; and other uses, 24%. Mine output came from 40 operations and was valued at $7.8 million in 1970. Crude output was processed by about 40 grinders, mostly in the same locations.

Vermiculite demand is predicted to increase domestically at an annual rate of 3.5%. In an expanded form, vermiculite is important commercially as a concrete aggregate and as a thermal insulating material, but faces competition from other low-cost products with similar properties such as perlite and pumice. Improvements to minimize the treatment losses in fine fractions or to provide a market for fine-size vermiculite could enhance the competitive position of vermiculite. Uses for vermiculite are many; it is a loose-fill insulating medium with or without the addition of a binder. Mixed with gypsum plaster, vermiculite forms an acoustical medium for sound absorption; with portland cement, a lightweight concrete results. Gypsum, clay, asbestos, and suitable cements are added to vermiculite to produce a fireproofing medium that can be applied to building structures. Agricultural uses are as soil conditioner, a plant growing medium, and a packing material for nursery stock. Construction utilizes 80% of production; agriculture, 14%; and other uses, 6%. One company accounted for nearly all of 1970 mine output, valued at $6.5 million, from three mining operations. One company predominates in exfoliating and operates 23 large plants in 20 states. In all, 25 companies operate 52 exfoliating plants in 33 states.

For the past twenty years, plastics production has been growing at an annual rate of between 10% and 15%. The 1969 production total was about 10 million tons, which is comparable with the nonferrous metals. Moreover, as first pointed out by Houwink ³ , the volume of plastics being produced is rapidly approaching that of all metals. Table 7.8 shows cubic feet of plastics, elastomers (rubbers), and fibers for 1968 and 1973 compared with ferrous and nonferrous metals ⁴ .

The production of key plastics by type, based on data by Jenest ⁵ is shown in Table 7.9 for 1969 and estimated 1974. The “big three” (known commonly as the polyethylene-polystyrene family and PVC) draw heavily on petroleum as a raw material, as shown in Table 7.10. Many additives are employed to modify plastic materials; the scale of their use is shown by the fact that such additives had a 1969 value of $0.8 billion compared to $3.8 billion for the plastic materials themselves ⁶ .

The financial characteristics of the plastics industry have been well summarized by Jenest ⁵ . Two aspects having a materials orientation are worth noting here. The first is the price-volume relationship. Figure 7.9 is a double logarithmic plot of pounds of different plastic materials sold in 1969 as a function of selling price. The line, as drawn, has a slope of −3, indicating the extreme sensitivity of sales volume to selling price. Certain plastics, notably Nylon 6 and fluorocarbons are sold in greater quantities than would be indicated by their price alone. Secondly, in comparing cost of plastics with metals, the large difference in density often requires that costs be expressed in price per unit volume. For example, a polycarbonate resin selling at about 75c/lb. costs 3.3c/cu. in. Zinc selling for about 18c/lb. costs 4.5c/cu. in. Thus, the polycarbonate is more than competitive with zinc in applications where its properties are adequate, particularly since the polycarbonate is easier to fabricate.

The major types of plastics-fabrication processes in use today ⁵ are shown in Table 7.11. One significant recent trend in plastics fabrication is that major end-users of plastics parts, such as the appliance and automotive industries, are undertaking the fabrication themselves with large and sophisticated facilities. Another trend is the increasing attention being given to the disposal of post-consumer plastic wastes. Reuse and recycling possibilities are currently receiving greater attention, as well as disposal via energy generation as fuel. Table 7.12 diagrams schematically the waste and recycle aspects of plastics.

Plastics as used for engineering purposes are usefully considered in terms of two major classes—engineering plastics and composition. Engineering plastic materials are specific polymers that have a combination of properties—strength, temperature resistance, solvent resistance, creep resistance, etc.—which permits them to be employed for structural purposes in engineered end-applications. Such materials are nylon, polyacetals, teflon, polycarbonates, polyphenylene oxide, etc. Composites—as the name implies—are mixtures of polymers or of polymers and inorganic materials in physical forms and ratios designed to develop specific properties: