XXV. ALUMINUM IN THE SOUTH J. D. PORTER, A ~ m r N u mCOBIPANY oa AMERICA,P ~ B U R GPENNSYLVANIA H,
The importance of the South to the aluminum industry is two-fold: (1) abundant water power means cheap electricity, which, to the economical production of alumiuum, is a fundamental necessity; (2) the new growth of iudustry in the South furnishes new markets close to aluminum production centers. The validity of this second consideration is attested by the fact that whereas hydroelectric power accounts only for the production of virgin aluminum in pig and ingot form, within the past year the Aluminum Company of America has installed a complete and extensive aluminum bronze powder mill to produce alumiuum paint pigment a t its Alcoa Works in Tennessee. For ten years, it should be noted, this same plaut has produced alumiuum sheet in large quantities, although the equipment originally installed had to do only with the electro-chemical reduction of refined ore into metallic aluminum. The development of mills to fabricate aluminum, in response to a growing industrial demand for these products, is itself a part of the industrial growth that fathered such development. From its start, the aluminum industry in the South has been largely a "home industry" in a natural and unforced manner, consuming vast amounts of native material and home labor in huge water-power developments, in building two model industrial towns, and in maintaining steadily mounting payrolls that flow through local arteries of trade. In North Carolina the production of aluminum centers about Badiu, near Salisbury, and in Stanly County. At this works, six pot rooms have been built since the first was erected in 1916. A carbon plant supplies the necessary electrodes and pot-lining material, while three power houses feed the pots with their required current. All three stations are on the Yadkiu River; The Narrows power house is at Badin, Yadkin Falls is several miles down river,,and High Rock is about thirty miles upstream. The town of Badin is entirely company-built, with streets, water supply, school buildings, church facilities, club accommodatious, all built or furnished by the company that has changed wilderness to industry, housing its employees in model homes and healthful surroundings. The city of Alcoa, adjoining Maryville, in Blount County, Tenn., has been built around a reduction plaut which started in the spring of 1914. In 1919 a carbon plaut was built to supply electrodes for this re'ductiou unit; a year later a sheet mill was completed. In 1929 an aluminum bronze powder plant was built to manufacture the metallic pigment used 23s
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in aluminum paint. This addition was built in direct recognition of the importance of the South as a paint-consuming field both industrially and for the home. During these fifteen years the original single pot-room installation has been added to until today there are ten pot rooms, with other buildings required to maintain these production units. Power is transmitted to Alcoa from the Cheoah and Santeetlah power houses of the Tallassee Power Company located up river from Alcoa; a third source of power will shortly be utilized when the station a t Calderwood, further up the Little Tennessee River, is completed. From a handful of employees, the payroll has increased to a total of approximately 3000 men. The town of Alcoa occupies land which in 1913 was almost entirely made up of farms on the outskirts of Maryville. Model homes have been built for employees, streets have been paved, adequate schools, hospital, churches, and other community activities are well housed and maintained. Blount County has advanced during these years of aluminum development from among the ten poorest of the ninetyfive counties in Tennessee to a rating of the tenth county in taxable wealth. The ore of aluminum is bauxite, mined largely in Arkansas and in South America. It contains aluminum oxide with water of crystallization and impurities consisting mainly of iron oxide, silica, and titanic acid. The ore is pnrified a t East St. Louis, Ill., through the use of a hot sodium hydroxide solution, which takes up the aluminum as sodium aluminate. After a filtering process has separated the aluminum-bearing liquor from the gangue, aluminum oxide is precipitated and thoroughly dried under intense heat. This oxide, called alumina, is shipped to reduction plants for conversion into metallic aluminum. Hall's process of reduction involves a solution of alumina in molten cryolite, through which an.electrical current is passed to bring down metallic aluminum at the bottom of the electrolytic pot in which this continuous production of aluminum takes place. These pots are steel shells lined with a carbon mixture, forming the cathode, while carbon rods lowered into the molten mixhue of cryolite and alumina act as the anode. The reduction of alumina to metallic aluminum involves a heavy expenditure of direct current electricity and of carbon electrodes. Aluminum, taken from the reduction pots periodically, is poured into pig fom, and is later remelted under close supervision, by chemical analysis and pyrometric control, to produce exact grades of pure commercial aluminum ingot or of standard alloys containing small amounts of copper, manganese, magnesium, silicon, etc., singly or in combmation. From the central research laboratory at New Kensington, Pennsylvania, branches of Aluminum Research Laboratories are maintained at all plants to perform the necessary work in connection with the technical
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control of processes as well as to carry on specified projects involving experimentation with new products and new processes. From the purification of the ore to the control of aUoys, the aluminum industry leans heavily upon chemical analysis and research in controlling standard processes and in developing new products and methods. The continued growth of aluminum-producing units can be indicated roughly by considering the industries that now consume the major portion of each year's production of aluminum. The development of strong aluminum alloys has brought strength equaling that of mild steel to this metal so long chosen for its lightness alone, and as a result, aluminum has a wide circle of outlets. In aviation, aluminum is used for aU pistons and for the great majority of propellers. The representative airplane engine employs aluminum for 50 per cent of its net volume, while fuselage and wing structures show an ever-increasing trend toward an extensive application of "Alclad" sheet and other forms of fabricated aluminum. "Alclad sheet has an inner core of strong aluminum alloy; the two outer surfaces are composed of thin layers of pure aluminum. This recently developed variety of sheet thus combines the strength of the inner core with the exceptional resistance of pure aluminum to many forms of corrosion. Aluminum furniture, made of sheet, formed and welded together to avoid all joints that might fail, has met with approval for such uses as dining car equipment, and for library, hotel, restaurant, and office installationswhere metal furniture that is light is a distinct economy over wood. In the electrical field aluminum is extensively used in cable form for transmission lines. Usually this cable has an inner core of high-strength steel stranding. A total of approximately 600,000,000 pounds of aluminum cable, steel-reinforced, is in service today. In this connection the abundant water power of the South, that invited the location of aluminum reduction works, has aiTorded an attractive market for aluminum electrical conductor cable. In this field aluminum busbar is a companion product of aluminum cable. Aluminum in architecture has shown remarkable growth in use during the past several years, supplying the demand for a white metal appropriate to modern architectural treatments, with an entirely satisfactory resistance to atmospheric corrosion. Many of the important new buildings in New York, Chicago, Pittsburgh, and other cities throughout the United States have employed aluminum as a material for spandrels, ornamental castings, window sills, copings, andother features requiring an ornamental metal that is durable. For residences, aluminum shingles with aU accessories have been developed and are being sold; for industrial purposes -gated roo6ng and siding, as well as standing and batten seam
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roofing, supplies a growing need for long-service, maintenance-free installations. In transportation aluminum is being adopted for truck, railway coach and street car bodies. The field of household electrical appliances has long been a steady market for aluminum in many forms. Collapsible tubes for tooth paste, sealing caps for bottles, and foil for candies, cigars, tea, etc., comprise a steady outlet in the packaging of food and allied products. Recently, equipment has been completed to produce strong aluminum alloys in structural shapes, similar to those in which iron has been a familiar material. Channels, I-beams, and other shapes can now be produced in aluminum in sizes up to fourteen inches in depth by eighty-five feet in length. Where power is expended to move weight, these structural members made of aluminum are finding many fields in which they offer an bttractive economy. When aluminum was first introduced as a commercial metal, about forty years ago, many enthusiastic predictions were made concerning the future of the new and wonderfully light metal. Many of these predictions will forever remain unfulfilled, but the introduction of strong aluminum alloys has brought some of them, a t least, to a surprising degree of accomplishment. The industry which had its birth in the electrochemical experiments of Charles Martin Hall in 1884, and which struggled for years to learn how to use its product, so that others might in turn be taught, can now look forward to a constant increase in consumption, even in those fields hitherto reserved for heavier metals. Recently constructed aluminum production and fabrication units in the South have a double significance in relation to the quickening of the South's industrial tempo; a minor importance measured by the part these newer plants themselves play in this accelerated trend; a major value when one notes in the southern field the many outlets for the aluminum produced there. Textiles, gas, oil, water resource development, sulfur, iron, and steel-all mean a market for aluminum in large quantities in various forms: paint, apparatus, electric transmission cable, busbar, and metallurgical ingot. Other industries inaease the scope and total of the aluminum market, which is further benefited by the high average standard of living incident to a region adapted to agriculture and rich in natural resources.
