Metal Alloys: Examples, Properties and Uses
An alloy is a metal that is obtained by mixing two or more metals together. Alloys that contain iron are called ferrous alloys, for example, steel. Alloys that do not contain iron are called non-ferrous alloys, examples include, brass, duralumin, bronze, etc.
1. Non-Ferrous Alloys:
a. Brass: Brass is an alloy. It is made up of a combination of 65% copper and 25% zinc. It can easily be worked on hand tools. If the copper content is up to 65%, brass can be ductile and can be bent when cold. It resists corrosion. It is therefore used for taps, valves, pipes, screws, etc. It is also used in producing musical instruments and ornaments.
b. Bronze: It is an alloy of copper and tin. It contains about 80% Copper and 20% Tin. It is reddish-brown in colour and has a beautiful appearance. It is used in making sculptures, producing medals, coins, springs, and architectural work.
c. Duralumin: is an alloy of aluminum. It contains 4.5% copper, 0.5% manganese, 0.5% magnesium, and 94.5% aluminium. It becomes hardened with age. It is used to make aircraft, automobile components, ships, and car machinery.
d. Gilding metal: is also an alloy of copper and zinc; It contains 90% copper and 10% zinc. It is used for making bowls, jugs, ashtrays, and jewellery.
e. Soft solder: It is an alloy of lead and tin. It contains about 68% lead and 32% tin. it is a strong material and is used in the production of plumbing tools, welding tools, and general metalwork.
f. Nichrome: This is the composition of nickel and chromium. It contains 80% Nickel and 20% Chromium. It can be used to manufacture electrical resistance wires for electric heating, for example, a Ring boiler.
2. Ferrous Alloys:
a. Wrought Iron: Wrought iron is an alloy of iron, carbon, sulphur, and phosphorous. It contains about 0.1% carbon. It is able to withstand sudden shock. It can resist corrosion. It is used for making couplings, chains, gates, railings, etc.
b. Cast Iron: It is an alloy of iron, carbon, silicon, manganese, sulphur and phosphorous. It contains 2 – 5% carbon. It is brittle and used to produce pipes, cookers, radiators, gates, etc.
c. Stainless steel: It is an alloy of iron, carbon, chromium, and nickel. It contains about 0.2% carbon. It is resistant to corrosion, takes a high finish, and will not rust. It is used to make cutlery, cutting tools, sink containers, bathroom taps, etc.
d. High-speed steel: It is an alloy of iron, carbon, tungsten, chromium, molybdenum, vanadium and cobalt. It contains about 0.6% carbon. It is hard and brittle and used to produce machine cutting tools, drilling tools, permanent magnets, etc.