Alloys

Slide 1

• Alloys

Sometimes Pure Metals are a problem

• The regular structure of pure metals makes them soft - often too soft for use one everyday life.
• Alloys are made by adding another element to the metal. This disrupts the structure of the metal, making alloys harder than pure metals
• For example: alloys of iron called steel are often used instead of pure iron. Steels are made by adding small amounts of carbon and sometimes other metals to iron.​​​​​​​
• Many alloys are used in everyday life

Slide 3

• Bronze = Copper + Tin
• Bronze is harder than copper. It's used to make medals, decorative ornaments and statues
• Gold alloys are used to make jewellery
• Pure gold is very soft. Metals such as zinc, copper, and silver are used to harden the gold. Pure gold is described at 24 carat, so 18 carats means that 18 out of 24 parts of the alloys are pure gold (75% gold)
• Brass = Copper + Zinc
• Brass is more malleable than bronze and is used in situations where lower friction is required, such as in water taps and door fittings
• Aluminium alloys are used to make aircraft
• aluminium has a low density which is an important in aircraft manufacture. But our aluminium is too soft for making aeroplanes so it is alloyed with small amounts of other metals to make is stronger