Artificial ageing affects the mechanical properties in terms of making the materials to form in a finer structure due to the fast cooling from 540 oC and ageing. This process will require the ageing to hold constant temperature at 170 oC in order to produce fine structure because the precipitates are small and closely located; therefore, the precipitates will diffuse into the grain which interfere the dislocation movement, and will result in a high strength and hardness of the specimen.