挤压变形对Mg-5.5Zn-1.7Nd-0.7Cd-0.5Zr合金组织和性能的影响

Effects of Extrusion Process on Microstructure and Mechanical Properties of Mg-Nd-Zn-Zr-Cd Magnesium Alloy

采用光学显微镜及透射电镜研究了Mg-5.5Zn-1.7Nd-0.7Cd-0.5Zr镁合金在不同挤压变形条件下的组织和性能。结果表明,在一定的挤压条件下,当挤压温度降低或挤压比增大,晶粒变细小,合金的抗拉强度和屈服强度提高;在温度为340℃,挤压比为16时,合金抗拉强度为334MPa,屈服强度为300MPa,伸长率为13%,力学性能优良,平均晶粒直径为7μm。

Microstructure and mechanical properties of Mg-5.5Zn-1.7Nd-0.7Cd-0.5Zr magnesium alloy were investigated under different extrusion rates by optical microscope(OM)and TEM(transmission electron microscope).It is revealed that at a defined extrusion condition,with decreasing in extrusion temperature or increasing in extrusion ratio,tensile strength and yield strength of the alloy are increasingly improved as a result of the refinement of grain size.Desirable mechanical properties of the alloy can be observed with extruding at 340℃and extrusion ratio of 16,where tensile strength,yield strength and elongation as well as average grain size reach 334MPa,300MPa and 13%,7 μm,respectively.