固溶时效处理对AZ91镁合金焊接接头组织性能的影响  

Effect of solid solution and aging treatment on microstructure and mechanical properties of AZ91 magnesium alloy welded joint

作　　者：刘政军[1] 屈佳兴 苏允海[1] 

机构地区：[1]沈阳工业大学材料科学与工程学院,沈阳110870

出　　处：《沈阳工业大学学报》2014年第3期263-268,共6页Journal of Shenyang University of Technology

基　　金：辽宁省教育厅基金资助项目(201124125);辽宁省博士启动基金资助项目(20131079)

摘　　要：为了明确热处理工艺对AZ91镁合金焊接接头组织性能的影响规律,进行了固溶时效处理工艺(T6)优化设计,确定了焊接接头的最佳热处理工艺.热处理后分别采用光学显微镜、扫描电子显微镜和拉伸试验机等对焊接接头的显微组织和力学性能进行了分析.结果表明,固溶处理可以提高焊接接头的抗拉强度与塑性;T6处理使其显微硬度提高,塑性下降,但焊接接头的综合力学性能得到提高.AZ91镁合金固溶处理的最佳工艺条件为420℃×15 h,其抗拉强度为283.22 MPa;最佳时效工艺条件为200℃×10 h,其抗拉强度为300.92 MPa.In order to clarify the influence of heat treatment technology on the microstructure and properties of AZ91 magnesium alloy welded joint,the optimization design of solid solution plus aging treatment（ T6） technology was performed,and the optimal heat treatment technology for the welded joint was determined. After the heat treatment,the microstructure and mechanical properties of welded joint was characterized with the optical microscope（ OM）,scanning electron microscope（ SEM） and tensile testing machine. The results showthat the solid solution treatment can improve the tensile strength and plasticity. The T6 treatment can enhance the microhardness, decrease the plasticity, and improve the comprehensive mechanical properties of welded joint. The optimum technological condition of solid solution treatment is 420 ℃ × 15 h, and the tensile strength is 283. 22 MPa. Moreover,the optimal technological condition of aging treatment is 200 ℃ × 10 h,and the tensile strength is 300. 92 MPa.

关 键 词：镁合金 焊接接头 固溶时效 抗拉强度 硬度 显微组织 断面收缩率 XRD图谱 

分 类 号：TG113.25[金属学及工艺—物理冶金]