steel wool, abrasive material composed of long steel fibers of varying degrees of fineness that are matted together. The coarser grades are used to remove paint and other finishes, the finer grades for polishing or smoothing a finished surface. Steel wool is much used in kitchens for cleaning and polishing metals, especially aluminum utensils.

steel industry, the business of processing iron ore into steel, which in its simplest form is an iron-carbon alloy, and in some cases, turning that metal into partially finished products or recycling scrap metal into steel. The steel industry grew out of the need for stronger and more easily produced metals. Technological advances in steelmaking during the last half of the 19th cent. played a key role in creating modern economies dependent on rails, automobiles, girders, bridges, and a variety of other steel products.

Iron working can be traced as far back as 3,500 B.C. in Armenia. The Bessemer process, created independently by Henry Bessemer in England and William Kelly in the United States during the 1850s, allowed the mass production of low-cost steel; the open-hearth process, first introduced in the United States in 1888, made it easier to use domestic iron ores. By the 1880s, the growing demand for steel rails made the United States the world's largest producer. The open-hearth process dominated the steel industry between 1910 and 1960, when it converted to the basic-oxygen process, which produces steel faster, and the electric-arc furnace process, which makes it easier to produce alloys such as stainless steel and to recycle scrap steel.

After World War II, the U.S. steel industry faced increased competition from Japanese and European producers, who rebuilt and modernized their industries. Later, many Third World countries, such as Brazil, built their own steel industries, and large U.S. steelmakers faced increased competition from smaller, nonunion mills ("mini-mills") that recycle scrap steel. The U.S. produced about half of the world's steel in 1945; in 1999 it was the second largest producer, with 12% of the world market, behind China and ahead of Japan and Russia.

Since the 1970s, growing competition and the increasing availability of alternative materials, such as plastic, slowed steel industry growth; employment in the U.S. steel industry dropped from 2.5 million in 1974 to to less than a million in 1998. Global production stood at 773 million tons in 1997, down from 786 million tons in 1988. U.S. steel production has remained constant since the 1970s at about 100 million tons, but 50% of that total is now produced by mini-mill companies. An increase in U.S. demand during the 1990s was largely met by imports, which now account for from about a fifth to a quarter of all steel used annually in the United States. The old-line U.S. steelmakers, losing market share and with higher wage, health, and retirement costs, experienced a string of bankruptcies beginning in the late 1990s, leading to industry and union pressure for protective tariffs, which were imposed by President George W. Bush in 2002 on most steel from non-NAFTA industrialized nations. Later reduced, the tariffs were found in 2003 to be illegal under World Trade Organization rules, and President Bush reversed the tariffs.

steel engraving: see engraving.

steel, alloy of iron, carbon, and small proportions of other elements. Iron contains impurities in the form of silicon, phosphorus, sulfur, and manganese; steelmaking involves the removal of these impurities, known as slag, and the addition of desirable alloying elements.

Production

Steel was first made by cementation, a process of heating bars of iron with charcoal in a closed furnace so that the surface of the iron acquired a high carbon content. The crucible method, originally developed to remove the slag from cementation steel, melts iron and other substances together in a fire-clay and graphite crucible. The famous blades of Damascus and of Toledo, Spain, were made by the cementation and crucible techniques.

The Bessemer process, the open-hearth process, and the basic oxygen process are more widely used in modern steelmaking. The open-hearth uses a type of furnace called a regenerative furnace; instead of a firebox at one end and a flue at the other, it has devices at each end for the intake and outflow of both fuel and air. The air is preheated by a system of current reversals that causes very high temperatures. This process, developed c.1866 by Sir William Siemens, uses iron ore and pig iron. In the basic oxygen process, or Linz-Donawitz process, developed in the 1950s, the design of the furnace is changed, and oxygen added to the air intake permits more rapid refining of the charge (material in the furnace). The electric-arc furnace is another modern development; it provides a means of making large quantities of high-grade steel, with the advantages of positive temperature control, freedom from contamination of the product by the fuel, and simultaneous deoxidation and desulfurization actions.

Steel is shaped for commercial use in rolling mills, where successive passages of the red-hot ingot between variously shaped rollers give it the desired form. Pittsburgh, one of the world's great steel centers, built its first rolling mill in 1811; Bessemer steel rails were rolled in Chicago as early as 1865.

Types and Uses

Steel is often classified by its carbon content: a high-carbon steel is serviceable for dies and cutting tools because of its great hardness and brittleness; low- or medium-carbon steel is used for sheeting and structural forms because of its amenability to welding and tooling. Alloy steels, now most widely used, contain one or more other elements to give them specific qualities. Aluminum steel is smooth and has a high tensile strength. Chromium steel finds wide use in automobile and airplane parts on account of its hardness, strength, and elasticity, as does the chromium-vanadium variety. Nickel steel is the most widely used of the alloys; it is nonmagnetic and has the tensile properties of high-carbon steel without the brittleness. Nickel-chromium steel possesses a shock resistant quality that makes it suitable for armor plate. Wolfram (tungsten), molybdenum, and high-manganese steel are other alloys. Stainless steel, which was developed in England, has a high tensile strength and resists abrasion and corrosion because of its high chromium content.

stainless steel: see steel.

Olcott, Henry Steel, 1832-1907, American religious leader and author, cofounder of Theosophist movement, b. Orange, N.J. After working as an agricultural scientist and a lawyer, he and Helena Blavatsky founded the Theosophical Society (1875) in New York City. In 1878, they moved the society to Adyar near Madras (now Chennai), India. Theosophy, a mixture of Eastern religion and Western occultism, has been influential in popularizing Asian philosophy in the West.

European Coal and Steel Community (ECSC), 1st treaty organization of what has become the European Union; established by the Treaty of Paris (1952). It is also known as the Schuman Plan, after the French foreign minister, Robert Schuman, who proposed it in 1950. Member nations of ECSC pledged to pool their coal and steel resources by providing a unified market for their coal and steel products, lifting restrictions on imports and exports, and creating a unified labor market. Economically, the Coal and Steel Community achieved early success; between 1952 and 1960 iron and steel production rose by 75% in the ECSC nations, and industrial production rose 58%. When overproduction of coal became a problem after 1959, especially in Belgium, the ECSC demonstrated its flexibility by reducing Belgium's coal-producing capacity by 30% and by making available large sums of money to aid in retraining miners and developing new industries. The ECSC had, by 1970, granted about $150 million in aid to retrain over 400,000 coal miners. The executive machinery of the ECSC provided an important precedent for the future growth of a united Europe: the nine-member High Authority, which became a part of the European Commission in 1967, was chosen by the member governments and made independent of those governments. Its independence was guaranteed by providing the authority with its own source of income.

Tuned gong made from the end, and part of the wall, of an oil barrel. The barrel's end surface is hammered into a concave shape, and several areas are outlined by chiseled grooves. It is heated and tempered, and bosses or domes are hammered into the outlined areas; the depth, curvature, and size of each boss determines its pitch. Melodies, complex accompaniments, and counterpoint can be played with rubber-tipped mallets on a single drum. The steel drum originated in Trinidad in the 1940s. It is usually played in ensembles, called steel bands, of widely varying sizes.

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Alloy of iron and about 2percnt or less carbon. Pure iron is soft, but carbon greatly hardens it. Several iron-carbon constituents with different compositions and/or crystal structures exist: austenite, ferrite, pearlite, cementite, and martensite can coexist in complex mixtures and combinations, depending on temperature and carbon content. Each microstructure differs in hardness, strength, toughness, corrosion resistance, and electrical resistivity, so adjusting the carbon content changes the properties. Heat treating, mechanical working at cold or hot temperatures, or addition of alloying elements may also give superior properties. The three major classes are carbon steels, low-alloy steels, and high-alloy steels. Low-alloy steels (with up to 8percnt alloying elements) are exceptionally strong and are used for machine parts, aircraft landing gear, shafts, hand tools, and gears, and in buildings and bridges. High-alloy steels, with more than 8percnt alloying elements (e.g., stainless steels) offer unusual properties. Making steel involves melting, purifying (refining), and alloying, carried out at about 2,900°F (1,600°C). Steel is obtained by refining iron (from a blast furnace) or scrap steel by the basic oxygen process, the open-hearth process, or in an electric furnace, then by removing excess carbon and impurities and adding alloying elements. Molten steel can be poured into molds and solidified into ingots; these are reheated and rolled into semifinished shapes which are worked into finished products. Some steps in ingot pouring can be saved by continuous casting. Forming semifinished steel into finished shapes may be done by two major methods: hot-working consists primarily of hammering and pressing (together called forging), extrusion, and rolling the steel under high heat; cold-working, which includes rolling, extrusion, and drawing (see wire drawing), is generally used to make bars, wire, tubes, sheets, and strips. Molten steel can also be cast directly into products. Certain products, particularly of sheet steel, are protected from corrosion by electroplating, galvanizing, or tinplating.

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Any of a family of alloy steels usually containing 10–30percnt chromium. The presence of chromium, together with low carbon content, gives remarkable resistance to corrosion and heat. Other elements, such as nickel, molybdenum, titanium, aluminum, niobium, copper, nitrogen, sulfur, phosphorus, and selenium, may be added to increase corrosion resistance to specific environments, enhance resistance to oxidation (see oxidation-reduction), and impart special characteristics.

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Alloy of iron and carbon in which the carbon content may range from less than 0.015percnt to slightly more than 2percnt. Adding this tiny amount of carbon produces a material that exhibits great strength, hardness, and other valuable mechanical properties. Carbon steels account for about 90percnt of the world's steel production. They are used extensively for automobile bodies, appliances, machinery, ships, containers, and the structures of buildings. Carbon steel, formerly made by the Bessemer, crucible, or open-hearth process, is now made by the basic oxygen process, or by an arc furnace.

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Administrative agency designed to integrate the coal and steel industries of France, West Germany, Italy, Belgium, the Netherlands, and Luxembourg. It originated in the plan of Robert Schuman (1950) to establish a common market for coal and steel by those countries willing to submit to an independent authority. Created in 1952, the ECSC came to include all members of the European Union. It initially removed barriers to trade in coal, coke, steel, pig iron, and scrap iron; it later supervised the reduction of its members' excess production. In 1967 its governing bodies were merged into the European Community. When the treaty expired in 2002, the ECSC was dissolved.

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