Aluminium and its alloys can be subjected to a variety of thermal treatments, such as:- Solution treatment, natural ageing, artificial ageing, annealing and stabilising or stress relieving.

The purpose of heat treating aluminium is to increase the strength and hardness of the alloy. Solution heat treatment on its own, initially increases the ductility of alloys, and enables a certain amount of cold working to take place, i.e bending, forming, stretching, before natural ageing starts to harden the metal.

Natural ageing increases the strength of the alloy, but artificial ageing is far better. Annealing, softens the alloy, to allow extreme bending and forming to take place, and stress relieving or stabilising is the relief of residual internal stresses, which is carried out at a predetermined temperature, which takes into consideration the mechanical properties of the alloy, taking care not to alter these properties.

Pictured below are types of components solution treated and artificially aged at G.H.T.L.