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Zinc based alloys of the Binary system of Zn-AI have wide industrial applications, such as Bearing and Bushing. Various physical metallurgical principles of Zinc-rich alloys have been fully investigated especially, their phase transformations near the room temperature. Less attention has been paid to the AI-rich alloy (with more than 20 wt% of Zn) of the
same Binary system. especially quench ¬ageing processes, near the room temperature. In the present article, the phase transformations of the AI based alloy (with 30 Wt% of Zn) after the quench ageing processes, natural and artificially aged at 1O0.C have been investigated. by mans of Electron Microscopy (T.E.M. S.T.E.M). Techniques. It has been shown
that the high temperature supersaturated Ii
phase is transferred to the stable 11- phase
by the formation of G.P Zones and two transitional phases called Ii m and a" m both with the F.C.C structures.