Sr对Mg-Gd-Y-Zr合金凝固组织和力学性能的影响

Effects of Sr on Solidified Structure and Mechanical Properties of Mg-Gd-Y-Zr Alloy

利用OM、SEM、EDS、XRD、ICP-AES及万能拉伸试验机等测试手段,分析了0~0.18%的Sr(质量分数)对Mg-6Gd-3Y-0.6Zr合金凝固组织和力学性能的影响。结果表明,随着Sr添加量提高,合金的晶粒尺寸逐渐减小,由42.5μm细化至21.8μm,第二相数量逐渐增多、尺寸逐渐减小、分布情况逐渐改善,其抗拉强度和伸长率提高,分别由170MPa、7.2%提高至192MPa、12.9%。试验中合金的力学性能主要受其凝固组织的影响,其凝固组织越细小,力学性能越高。

The effects of 0~0.18%Sr on the solidification structure and mechanical properties of Mg-6Gd-3Y-0.6Zr alloy were investigated by OM,SEM,EDS,XRD,ICP-AES,universal tensile testing machine and other testing methods.The results show that with the increase of Sr addition,grain size in the alloy is decreased gradually from 42.5μm to 21.8μm.The second phase is increased gradually with the decrease of size gradually,and its distribution is improved gradually.Tensile strength and elongation of the alloy are increased gradually from 170 MPa and 7.2%to 192 MPa and 12.9%,respectively.Under the condition of the given experiment,mechanical properties of the alloy is mainly controlled by solidification structure of the alloy.With decreasing in the solidification structure,the mechanical properties are improved obviously.