Classes of Materials and their Properties

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
We can classify materials according to their . However, within each of material the properties can vary widely. The properties can also change with as the weather changes.

Metals, such as Iron and steel, are strong in and compression. they are hard, and tough. They are good of electricity and heat. They are shiny and reflect .


Metal tubes are often used in the construction of . The use of tubes has a number of advantages. They are because they use less steel. They are than using solid rods of steel. This gives a lower overall for the bridge. The tubes are also stiffer and than using flat sheets of steel. The bridge needs protection against from the salt in the air, and this is provided by covering the bridge with a special .

such as bricks, tiles and crockery, are strong in by weak in tension. There are very materials. Ceramics are very good of electricity and heat.

such as polythene, PVC and perspex are often flexible and they are strong for their . They are usually soft and are easily . They are excellent thermal and electrical . They are usually transparent or .


Polymers are used widely in cars. They are lightweight, and flexible. The plastic bumpers at the front to the car allow to be absorbed during collisions. The plastic parts on the outside also prevent from entering the vehicle. Plastic does not when wet, unlike iron and .


Plastics are used widely in the clothes industry and fashion world. This is a plastic model kept outside in all weathers. It is durable and tough. Plastic with low points would be unsuitable for the high in the Summer. Many fashion clothes are made in plastic. They are not suitable for hot weather, unless provision is made for water to escape from the body. Plastics are suitable for protection in wet weather because they are .

materials consist of two or more different materials. Modern composite materials are usually made with fibres embedded in a . This material protects the fibres from and helps to share the between all the fibres. The fibres provide to the composite material. Carbon Fibre Reinforced Plastic (CFRP) is used widely in sports and the aircraft industry. They provide very high strength to ratio. This allows structures to be light in weight but be very and stiff.


Saving weight is important in aircraft. It allows the aircraft to carry more or payload, and can increase the overall and range of the aircraft.


This building, in Northern Arizona, is made from a composite material. It provides a streamline shape to withstand high . It does not rot unlike , and it does not unlike iron and steel. It is resistant to attack by termites, unlike wood. The fibreglass construction also provides good heat . This allows the building to be in cold weather, and in hot weather.