Evaluation of the effect of bismuth on Mg2Si particulate reinforced in Al-20%Mg2Si in-situ composite

Abstract

Al-Mg2Si in-situ composite as a class of advanced engineering materials has possessed better properties which enhanced them to be potential candidate to manufacture most of automotive and aerospace components. Melt treatment of the in-situ composite by addition of bismuth, Bi has resulted in a change of primary Mg2Si reinforcement to a refined morphology which would expect to improve mechanical properties of the composite. Characteristics parameters of Mg2Si particles have been investigated via thermal and microstructural analysis. It has revealed that 0.4wt.% Bi addition produced optimum refinement effect on the morphology since coarse structure has been change to polygon one and reduced most in size. The result also showed depression in nucleation temperature, TN and growth temperature, TG which also correspond to the refinement effect.