9.6 - Uses of Metals

Why a metal suits its job

• A metal is picked for a job because of its properties.
• While all metals conduct heat and electricity and have relatively high strength, they differ in density, conductivity, hardness, and reactivity.

Aluminium - Low density

Aluminium has a low density (light for its size):

• Aircraft - Low density keeps the aircraft's mass down.
• Overhead electrical cables - Low density combined with good electrical conductivity allows cables to hang between pylons without breaking under their own weight.
• Food containers - Resists corrosion, so it doesn't react with food.

Copper - Conductor and ductile

Copper is a very good conductor of heat and electricity, and it's ductile (can be drawn into a wire without snapping):

Electrical wiring - good conductivity carries the current efficiently, and ductility allows it to be drawn into thin wires.