Effects Of Ca, Nd, Er On Microstructures And Properties Of AZ91Magnesium Alloy

In this paper, the effects of Ca, Nd, Er addition on microstructures,mechanical properties and corrosion resistance of AZ91magnesium alloys werestudied by XRD, OM, SEM, EDS and immersion test.The Ca, Nd, Er all can refine the grain of AZ91magnesium alloy and therespectively minimum grain sizes are17μm,20μm,17μm. The phases as Al2Caare found by adding Ca. The tensile strength of AZ91-1.25%Ca alloy is151MPa, which is13.6%higher than AZ91magnesium alloy.The β phases are discontinuous strips or particle-like shapes and there areAl2Nd, Al11Nd3in the matrix by adding Nd. The tensile strength of AZ91-0.87%Nd alloy is221.4MPa. The tensile strength of AZ91-0.87%Nd alloy is67.7%higher than that of AZ91magnesium alloy.The β phases that are particle-like shapes are uniformly distributed in thematrix and phases as Al2Er are found by adding Er. The tensile strength of AZ91-1.81%Er is150MPa. The tensile strength of AZ91-1.81%Er is21.1%higherthan that of AZ91magnesium alloy. It is show that the corrosion rate ofAZ91-1.81%alloy is the lowest among the same group. So Er can improve thecorrosion resistance of AZ91magnesium alloy.