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.

Comparing properties of alloys and pure metals

Many pure metals are too soft for many uses. They can be made harder by adding another element to the pure metal, so forming an alloy. This explains why an alloy often has more uses than the pure elements it is made from.

Pure iron, for example, is very soft. Adding a small amount of tungsten to iron makes tool steel, which is harder than pure iron. Steels are examples of alloys. There are many types of steel.

Mild steelCarbon and ironEasy to bend and pull into wires
Tool steelTungsten and ironHard, can be heated to high temperatures
Stainless steelChromium and ironHard, does not rust easily