It is important to perform the precipitation ageing at an appropriate temperature of 165-175 oC to gain the peak hardness of the material. On the other hand, if the precipitation ageing is performed at lower or higher temperature, it will cause an unsatisfactory hardness to that particular material, which will result in a deformation. There are mainly 5 sequences of precipitation that will occur accordingly during ageing, which are β’’/ β’ GPI θ’’ θ’ θ.