元素Sr对铸态Mg-2Zn-1Mn合金力学性能的影响

Effect of Element Sr on Mechanical Properties of as Cast Mg-2Zn-1Mn Alloy

采用光学显微镜、扫描电镜、X射线衍射仪等分析研究Sr对Mg-2Zn-1Mn铸造镁合金组织和性能的影响,并测试其室温拉伸性能。研究结果表明:随着Sr元素的加入,合金平均晶粒尺寸明显变小,并且晶间析出Mg17Sr2相。随着Sr含量的增加,第二相的存在形式逐渐从孤立粒子演变为条状,然后演变为半连续或连续网格状,且第二相的体积呈线性增长。添加0.2wt.%Sr后,晶粒尺寸从101.12μm减小到76.92μm,合金抗拉强度和屈服强度都分别达到了最大值201.6MPa和50.2MPa,伸长率也达到最大值13.8%。

The effects of Sr on the microstructure and properties of Mg-2Zn-1Mn cast magnesium alloy were analyzed and studied by light microscopy,scanning electron microscopy,and X-ray diffraction,and its tensile properties at room temperature were tested.The results show that with the addition of Sr,the average grain size of the alloy decreases significantly,and Mg17Sr2 phase precipitates between grains.With the increase of Sr content,the existing form of the second phase gradually evolves from isolated particles to strip shaped particles,and then to semi continuous or continuous grid shaped particles,and the volume of the second phase increases linearly.After adding 0.2 wt.%Sr,the grain size changes from 101.12μM reduced to 76.92μm.The tensile strength and yield strength of the alloy reached the maximum values of 201.6Mpa and 50.2Mpa,respectively,and the elongation also reached the maximum value of 13.8%.