Effect of Zn on Microstructure and Mechanical Properties of As-cast Mg-3%Al Alloys

The effects of Zn contents (1%-8%) on microstructure,mechanical properties of Mg-3%Al alloys were investigated by OM,universal testing machine,XRD and EPMA.The results show that the Zn addition affected the microstructure and properties obrionsly of the Mg-3%Al alloy.The microstucture of the alloys with Zn addition of 6% contained α-Mg,β-Mg17Al12 and τ-Mg32(Al,Zn)49 phases.The microstructure was refined significantly,and the phases distribution were improved.The mechanical properties reached the best values of σb=215 MPa,δ=11.3% and ψ=11.2%.