Study on microstructure of rare earth Mg-9%Gd-2%Y-3%Nd -0.7%Zr alloy and properties of micro-arc oxidation films

Abstract The micro-arc oxidation protective film has been prepared on the surface of Mg-9%Gd -2%Y-3%Nd-0.7%Zr alloy by using microarc technique “step step depressurization”. microstructure magnesium substrate and were measured OM, SEM XRD, properties evaluated electrochemical test thickness morphology. results show that discontinuous network multiple eutectic phases are distributed in grain boundary there dispersed-granular precipitates matrix. After treatment, corrosion resistance increased with increase time, micropore size first then decreased, morphology changed from no micro-crack to micro-crack, finally disappeared.