4.10.3.2

Alloys as useful materials

Contents

Most metals in everyday use are alloys.

Bronze is an alloy of copper and tin. Brass is an alloy of copper and zinc.

Gold used as jewellery is usually an alloy with silver, copper and zinc. The proportion of gold in the alloy is measured in carats. 24 carat being 100% (pure gold), and 18 carat being 75% gold.

Steels are alloys of iron that contain specific amounts of carbon and other metals. High carbon steel is strong but brittle. Low carbon steel is softer and more easily shaped. Steels containing chromium and nickel (stainless steels) are hard and resistant to corrosion.

Aluminium alloys are low density.

Students should be able to:

  • recall a use of each of the alloys specified
  • interpret and evaluate the composition and uses of alloys other than those specified given appropriate information.

MS 1a - Recognise and use expressions in decimal form

MS 1c Use ratios, fractions and percentages