Alloys

Alloys

What are they used for?

• 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.

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How do they make metal stronger

Alloys contain atoms of different sizes, which distort the regular arrangements of atoms. This makes it more difficult for the layers to slide over each other, so alloys are harder than the pure metal.

What are alloys?

Alloys are a mixture of metals, or metals mixed with small amounts of other materials. This to strengthen and to stop corrosion.

Brass is an alloy because its a mixture of copper and iron.