brass (redirected from Arsenical brass)

brass, alloy having copper (55%–90%) and zinc (10%–45%) as its essential components. The properties of brass vary with the proportion of copper and zinc and with the addition of small amounts of other elements, such as aluminum, lead, tin, or nickel. In general brass can be forged or hammered into various shapes, rolled into thin sheets, drawn into wires, and machined and cast. Its ductility reaches a maximum with about 30% zinc and its tensile strength with 45%—although this property varies greatly with the mechanical and heat treatment of the alloy. Cartridge brass (70% copper, 30% zinc) is used for cartridge cases, plumbing and lighting fixtures, rivets, screws, and springs. Aluminum brass (not exceeding 3% aluminum) has greater resistance to corrosion than ordinary brass. Brass containing tin (not exceeding 2%) is less liable to corrosion in seawater; it is sometimes called naval brass and is used in naval construction. Dutch metal (80%–85% copper, 15%–20% zinc) is used as a substitute for gold leaf. When iron is added to brass it produces hard, tough alloys. One of these is delta metal (55% copper, 41% zinc, 1%–3% iron, and fractional percentages of tin and manganese), which can be forged, rolled, or cast and is used for bearings, valves, and ship propellers.

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brass

Alloy of copper and zinc, important for its hardness and workability. Brass was first used c. 1200 BC in the Near East, then extensively in China after 220 BC, and soon thereafter by the Romans. In ancient documents, including the Bible, the term brass is often used to denote bronze (copper/tin alloy). The malleability of brass depends on its zinc content; brasses with more than 45% zinc are not workable. Alpha brasses contain less than 40% zinc; beta brasses (40–45% zinc) are less ductile than alpha brasses but stronger. A third group includes brasses with additional elements. Among these are lead brasses, which are more easily machined; naval and admiralty brasses, in which a small amount of tin improves resistance to corrosion by seawater; and aluminum brasses, which provide strength and corrosion resistance where the naval brasses may fail.

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brass

1. an alloy of copper and zinc containing more than 50 per cent of copper. Alpha brass (containing less than 35 per cent of zinc) is used for most engineering materials requiring forging, pressing, etc. Alpha-beta brass (35--45 per cent zinc) is used for hot working and extrusion. Beta brass (45--50 per cent zinc) is used for castings. Small amounts of other metals, such as lead or tin, may be added

2. 

a. the large family of wind instruments including the trumpet, trombone, French horn, etc., each consisting of a brass tube blown directly by means of a cup- or funnel-shaped mouthpiece

b. instruments of this family forming a section in an orchestra

3. a renewable sleeve or bored semicylindrical shell made of brass or bronze, used as a liner for a bearing

4. Brit an engraved brass memorial tablet or plaque, set in the wall or floor of a church

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brass [bras]

(geology)

A British term for sulfides of iron (pyrites) in coal. Also known as brasses.

(metallurgy)

A copper-zinc alloy of varying proportions but typically containing 67% copper and 33% zinc.