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Laser has many attractive specifications which made it adaptable for material processing. Laser was taken as a modern heat treatment source to prevent the formation of non-protective oxide layer with intensity equal to 1.31ž105w/cm2 ,lasing time equal to 300mis wave length equal to 1.063mim ,and spot radius equal to 125mim. Lithium is depleted during the conventional heat treatment processes . The conventional heat treatment results and laser calculations have been investigated in this work . The comparison between laser calculations and the conventional heat treatment results were studied . The two main factors affected lithium depletion are; temperature and time , if these increase the Li-depletion will increase to the maximum values, while by using laser radiation the Li-depletion and diffusion will reach the minimum values and kept it as a solid solution at casting. The microrhardness of the affected zone will reach to acceptable values for various ageing times and hardening depths ,this improvement will allow the materials specifications to reach the optimal values. The main three conventional heat treatment processes are: homogenization, solution heat treatment, and ageing.

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