Expert: Ray Wilkinson - 5/6/2007

Question
how metal used inthe aeroplane can suffer extreme heat?which metal is used? is metal used in war planes are different?

Answer
Hi Kunu

All metals have a melting point, and also a temperature at which they begin to lose their strength. The secret is to use a material that will be strong enough at the temperature it will be exposed to. So, most aircraft use aluminium alloy, which is strong up to about 130 Celsius. If the material gets any hotter, you need to use more material or a material suitable for the higher temperature like titanium or steel. An example would be in and around enngines. For the skin and main structure of most aircraft, aluminium alloy is fine. Even Concorde used alloy structue and skin, but took it right up to the limit.

However, many aircraft are now starting to use composite materials, like glassfibre, carbon fibre and Kevlar. These have similar temperature limits but are generally lighter. Military aircraft use more composites than civil aircraft, because they started using it earlier, but civil aircraft are using more and more.

I hope this answers your question.

Regards

Ray