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The nonferrous metals are copper and its alloys (such as brass and bronze), aluminum, magnesium, lead, zinc, and tin.

Alloy. An alloy is a substance that has metallic properties and is composed of two or more chemical elements of which at least one is a metal. The number of possible alloys is infinite. They are made by the fusion of metals. The most common groups of alloys are bronze, brass, babbitt, alloy steels, and the aluminum alloys.

Copper. In commercial importance, copper ranks next to iron and steel, because of its electrical conductivity and its capacity to form useful alloys. Copper is soft enough to be rolled, or hammered into thin sheets, or drawn into fine wire. It is used for ignition and instrument wires on engines, tubing for conducting fuel from tank to carburetor, and in generator and starting motors.

Brass. Ordinary brass is an alloy of copper and zinc. Some commercial brasses contain small percentages of lead, tin and iron. The percentage of copper in brass may range from 60 to 90 per cent, and the percentage of zinc from 10 to 40 per cent. Brass is used for making radiators, pipe, welding rods, screens for fuel lines, instrument parts, and fittings.

Bronze. Bronze is an alloy of copper and tin. However, zinc is sometimes added to cheapen the alloy or change its color and increase its malleability. The amount of tin in bronze may vary from 5 to 20 per cent. Phosphor bronze, manganese bronze, and aluminum bronze are special copper alloys containing small percentages of tin, zinc, and other metals such as phosphorus, manganese, or aluminum. These are used for bearing bushings, springs, pipe fittings, valves, pump pistons, and bearings.

Babbitt. Babbitt is a tin-base alloy containing small amounts of copper and antimony. Good babbitt for automobile bearings should contain 7 per cent copper, 9 per cent antimony, and 84 per cent tin. It is used mostly as a bearing metal.

Solder. Common solder contains about one part tin and one part lead. Hard plumbers’ solder contains two parts tin and one part lead. Solder is used extensively in joining brass, copper, tin, steel, and cast iron.

Bearing Metals. White metals and bronze alloys are most frequently used for machine bearings, but wood, glass, plastics, rubber, and other materials are also used.

Aluminum. This is a white metal with a bluish tinge. It has a specific gravity of 2.7, a melting point of 658.7°C., and is resistant to corrosion and to many chemicals. It, however, can be dissolved by alkalies and hydrochloric acid. It is frequently alloyed with iron and copper. Aluminum is extensively used to make light castings for certain types of farm equipment.

Zinc. Zinc is a bluish-white, crystalline, metallic element, brittle when cold, malleable at 110 to 210°C. It is used mostly as a coating on sheet iron and die castings, as a protection against corrosion.