bronze

bronze, in metallurgy

bronze, in metallurgy, alloy of copper, tin, zinc, phosphorus, and sometimes small amounts of other elements. Bronzes are harder than brasses. Most are produced by melting the copper and adding the desired amounts of tin, zinc, and other substances. The properties of the alloy depend on the proportions of its components. Aluminum bronze has high strength and resists corrosion; it is used for bearings, valve seats, and machine parts. Leaded bronze, containing from 10% to 29% lead, is cast into heavy–duty bushings and bearings. Silicon bronze is used for telegraph wires and chemical containers. Phosphor bronze is used for springs. Bronze is used for coins, medals, steam fittings, and gunmetal and was formerly employed for cannon. Because of its particularly sonorous quality, bell metal, containing from 20% to 24% tin, is used for casting bells. Bronze has long been used in art, e.g., for castings, engravings, and forgings.

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bronze, in art

bronze, in art: see bronze sculpture.

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bronze

Alloy traditionally composed of copper and tin. Bronze was first made before 3000 BC (see Bronze Age) and is still widely used, though iron often replaced bronze in tools and weapons after about 1000 BC because of iron's abundance compared to copper and tin. Bronze is harder than copper, more readily melted, and easier to cast. It is also harder than iron and far more resistant to corrosion. Bell metal (which produces pleasing sounds when struck) is bronze with 20–25% tin content. Statuary bronze, with less than 10% tin and an admixture of zinc and lead, is technically a brass. The addition of less than 1% phosphorus improves the hardness and strength of bronze; that formulation is used for pump plungers, valves, and bushings. Also useful in mechanical engineering are manganese bronzes, with little or no tin but considerable amounts of zinc and up to 4.5% manganese. Aluminum bronzes, containing up to 16% aluminum and small amounts of other metals such as iron or nickel, are especially strong and corrosion-resistant; they are cast or wrought into pipe fittings, pumps, gears, ship propellers, and turbine blades. Most “copper” coins are actually bronze, typically with about 4% tin and 1% zinc, or copper plating over base metal.

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bronze

1. 

a. any hard water-resistant alloy consisting of copper and smaller proportions of tin and sometimes zinc and lead

b. any similar copper alloy containing other elements in place of tin, such as aluminium bronze, beryllium bronze, etc

2. a yellowish-brown colour or pigment

3. short for bronze medal