Metals are found naturally and are mined from the earth. Metals used in products are extracted from the natural ore using large heat furnaces. They are sold as sheets, bars, rods, tubes and angles. Most metals can be recycled, saving natural resources.
Ferrous metals contain iron and are magnetic. They are prone to rust and therefore require a protective finish, which is sometimes used to improve the aesthetics of the product it is used for as well.
|Cast iron||Brittle if thin, can be cast in a mould, strong compression strength, good electrical and thermal conductivity but poor resistance to corrosion||Manhole covers, pans and gates, vices|
|High-carbon steel (tool steel)||Hard but brittle, less malleable than mild steel, good electrical and thermal conductivity||Taps and tools, eg screwdrivers and chisels|
|Low-carbon steel (mild steel)||Ductile and tough, easy to form, braze and weld, good electrical and thermal conductivity but poor resistance to corrosion||Nuts, bolts, screws, bike frames and car bodies|
Non-ferrous metals do not contain iron and are not magnetic. They do not rust.
|Aluminium||Light in weight and malleable but strong, a good conductor of heat and corrosion resistant||Drink cans, saucepans, bike frames|
|Copper||An excellent electrical conductor of heat and electricity, extremely malleable and can be polished, oxidises to a green colour||Plumbing fittings and electrical wires, professional chef's saucepans|
|Silver||A precious metal that is soft and malleable when heated, highly resistant to corrosion and an excellent electrical conductor of heat||Jewellery|
Alloys are mixtures of metal with an element to improve its properties or aesthetic. For example brass is a mixture of copper and zinc. Alloys can also be classified as ferrous or non-ferrous. Non-ferrous metal may require a protective finish. This finish is sometimes used to improve the aesthetics of the product it is used for.
|Brass (alloy of copper and zinc)||Non-ferrous metal that is strong and ductile, casts well and is gold coloured but darkens when oxidised with age, a good conductor of heat||Taps, screws, castings, locks and doorknobs|
|Bronze (alloy of copper, aluminium and/or nickel)||Non-ferrous alloy, harder than brass and corrosion resistant, reddish/yellow in colour||Castings, bearings|
|Stainless steel (alloy of steel also with chromium, nickel and magnesium)||Ferrous metal that is silver when polished, hard and tough with excellent resistance to corrosion||Cutlery, sinks, saucepans, surgical equipment|