What is an Alloy?
An alloy is a mixture of two or more elements, where at least one element is a metal. Many alloys are mixtures of two or more metals.
Copper, gold and aluminium are too soft for many uses. They are mixed with other metals to make them harder for everyday use. For example:
- Brass - used in electrical fittings - is 70 per cent copper and 30 per cent zinc
- 18-carat gold - used in jewellery - is 75 per cent gold and 25 per cent copper and other metals
How do they work?
Shape memory alloys can return to their original shape after being bent or twisted. Nitinol is a shape memory alloy made from nickel and titanium. It is used in dental braces and spectacle frames.