Most metals are extracted from their ores using a chemical reaction. Metals are rarely used in their pure form, and are usually mixed with other metals to improve their properties. This is called an alloy. Most metals are good conductors and can be recycled.
Ferrous metals
Ferrous metals contain iron. Examples are cast iron, mild steel, medium carbon steel, high carbon steel, stainless steel and high speed steel.
The ferrous metals listed below are all alloys.
Composition, properties and uses of ferrous metals
| Name and melting point | Properties and characteristics | Principal uses |
|---|---|---|
| Cast iron 1200°C | Hard skin, softer underneath, but brittle,corrodes by rusting | Parts with complex shapes which can be made by casting |
| Mild steel 1600°C | Tough, ductile, malleable, good tensile strength, poor resistance to corrosion | General purpose engineering material |
| High carbon steel 1800°C | Even harder than medium carbon steel and more brittle, can be heat-treated to make it harder and tougher | Cutting tools, ball bearings |
| Stainless steel 1400°C | Hard and tough, resistant to wear and corrosion | Cutlery, kitchen equipment |
Non-ferrous metals
Non-ferrous metals do not contain iron. Some common non-ferrous metals are aluminium, Duralumin, copper, zinc, brass, gilding metal and tin.
Composition, properties and uses of non-ferrous metals:
| Name and melting point | Composition | Properties and characteristics | Principal uses |
|---|---|---|---|
| Aluminium 660°C | Pure aluminium | Good strength-to-weight ratio, light, soft, ductile, good conductor of heat and electricity | Kitchen equipment, window frames, general cast components |
| Copper 1080°C | Pure copper | Malleable and ductile, good conductor of heat and electricity, resistant to corrosion | Water pipes, electrical wire, decorative goods |
| Brass 900-1000°C | Alloy | Resistant to corrosion, fairly hard, good conductor of heat and electricity | Ornaments, cast items such as water taps |
| Tin 230°C | Pure tin | Soft, weak, malleable, ductile and resistant to corrosion | Usually used for coating steel to form tin-plate, soft solder |
