固溶处理对Mg-xGd-0.3Zr合金微观组织及力学性能的影响

摘要

为了探究不同含量稀土元素Gd对镁合金微观组织及力学性能的影响,采用光学显微镜、X射线衍射、扫描电子显微镜、透射电子显微镜及电子万能试验机,研究了镁合金固溶处理过程中的显微组织和力学性能.研究结果表明:合金铸态组织主要由α-Mg、共晶组织和第二相组成,固溶处理过程共晶相完全溶解,但是在晶界上仍然存在未溶解第二相;随着Gd含量的增加,第二相逐渐增多,晶粒显著细化,合金的抗压强度和屈服强度呈线性增大.%The influence of the Gd content on microstructure evolution and mechanical behavior of the Mg-x Gd-0.3Zr magnesium alloy is investigated by optical microscope (OM),X-ray diffraction (XRD),scanning electron microscope (SEM),transmission electron microscope (TEM) and compression test after solution treatment.The results show that the as-cast alloy is mainly composed of α-Mg,eutectic tissue and second phase.After the solution treatment the eutectic phase is completely dissolved,but there is still no undissolved second phase in the grain boundary.With the increase of Gd content,the second phase gradually increases,grain refines,the compression strength and yield strength of the alloys increase linearly.