Effect Of Strain Rate On The Tensile Properties Of Mg-Zn-Nd Alloy

Our country is rich of magnesium and rare-earth, and we have the advantage of producing high-class magnesium-rare earth. Because the mechanical properties of as-extrude magnesium alloys are better than the as-cast magnesium alloys, the developing of as-extrude magnesium alloy will make it be widely used as the structure. There are still many problems as processing of as-extrude magnesium alloy's plastic deformation need to be settled.In this paper, as-extrude Mg-Zn-Nd alloys are used as the test materials. Through tensile tests performed under both different temperatures and strain rates, the influence of temperature and strain rate on the tensile properties of as-extrude Mg-Zn-Nd alloys are studied. By means of SEM, observations on fracture surfaces were carried out and features of fractures of as-extrude Mg-Zn-Nd alloys were studied.The results shows: as-extrude Mg-Zn-Nd alloys are sensitive of strain rate. At the same temperature, with increasing of strain rate, the tensile strength and the yield strength are increased, but the elongation is decreased. With increasing of temperature, the tensile strength and the yield strength are decreased, but the elongation is increased. The influence of strain rate on as-extrude Mg-Zn-Nd alloys's tensile properties at higher temperature is bigger than at lower temperature.Fracture surface analysis revealed that as-extrude Mg-Zn-Nd alloys are subjected to ductile fracture. With the increasing of strain rate, the number of dimples is decreased, and on the fracture surfaces the larger and shallower dimples could be observed. By increasing temperature, the more and deeper dimples could be observed.