Influence of Heat Treatment on the Microstructure and Property of Mg-Nd-Gd-Zn-Zr Alloy

The influence of heat treatment process on the microstructure and property of Mg-Nd-Gd-Zn-Zr magnesium alloy was studied. The results show that, with the increase of the solid solution temperature, the grains of the alloy grow obviously and its elongation rate is decreased, but the residual second phase in grain boundary reduces, and the fracture mode of the alloy changes from a combination of second-phase fracture and trans-grain fracture to the trans-grain cleavage fracture; with the increase of solution time, the change of the tensile strength is not evident and the elongation rate is increased, but oxidation extent tends to increasing; the double-stage ageing process can improve the elongation rate, but the tensile strength is lowered to some extent.