THE EFFECTS OF Bi ADDITION AND HEAT TREATMENT ON THE MICROSTRUCTURE AND TENSILE PROPERTIES OF AL-15%Mg2Si COMPOSITE

In current research, the influence of different concentration of Bi (0.01-0.3 wt.%) on the microstructure and tensile properties of Al-15%Mg2Si in situ metal matrix composite before and after heat treatment has been investigated. Optical microscopy (OM) and scanning electron microscopy (SEM) showed that 0.03 wt.% Bi addition not only changes the morphology of primary Mg2Si irregular to polyhedral shape and its average particle size decrease from ~65 μm to 20 μm but also showed that 0.03 wt.% Bi, morphology of the eutectic Mg2Si phase alters from flak like to fine fibers or rod like. The results of tensile testing demonstrated that the ultimate tensile strength (UTS) and elongation values of the composite increase with the addition of Bi (0.03 wt. %). The results also showed that applying solution heat treatment improves the toughness of the composite significantly

کلیدواژه ها:

Al-Mg2Si Composite ، Intermetallic ، Microstructure ، Tensile properties