Metals, Alloys and Smart Alloys Learning Objectives: To understand that the uses for certain metals relate to their specific properties. To understand that the properties of metals can be improved by producing alloys. To recall that some of the latest alloys, called ‘Smart Alloys’ can alter their properties on demand.

Copy the table below. Working with a partner, complete as much of the table as you can. MetalPropertiesUses Aluminium Copper Gold Steel Low density, strong, resistant to corrosion, good conductor of electricity Good conductor of electricity, resistant to corrosion, easily shaped, flexible Shiny, very resistant to corrosion, very unreactive, soft, easily shaped Very strong, very dense. Lightweight structures, aircraft, drinks cans, high voltage cables. Electrical wiring, water pipes. Jewellery. Large structures and heavy duty engineering such as bridges, trains, cars etc.

In pure metals the atoms arrange themselves closely together into regular patterns. This makes them dense and also gives them many of their other useful properties.

The layer arrangement of the atoms allows the metals to change shape if a force is applied. The layers can slip over each other. This can be useful if you want to shape the metal but not so useful if you want it to resist the force and be strong.

By mixing two or more metals together the regular arrangement of the atoms is disrupted. This prevents the atoms forming layers and makes it harder for the atoms to slide over each other. The alloy is stronger than the pure metals. Metal B Metal A

Steel is an alloy. Pure iron is not strong enough to be used in structures. Steel contains a small amount of carbon. This disrupts the layers of atoms in the metal and increases the strength of the metal considerably. Although it is very strong steel will corrode (rust) easily and it has to be constantly protected from the effects of water and air.

Stainless steel is an alloy that contains other metals such as Nickel and Chromium. Stainless steel has the strength of steel combined with the corrosion resistance of nickel and the shininess of chromium. This makes it a useful material in applications where you need strength combined with beauty and corrosion resistance..

Smart Alloys These are alloys that can ‘remember’ their original shape. If they are deformed they can return to their original shape. Shape memory glasses Shape memory Stent to keep a blocked blood vessel open

Metals, Alloys and Smart Alloys Learning Objectives: To understand that the uses for certain metals relate to their specific properties. To understand that the properties of metals can be improved by producing alloys. To recall that some of the latest alloys, called ‘Smart Alloys’ can alter their properties on demand.