Influence of Hot Compression Deformation on Microstructures and Mechanical Properties of Welded Joints for AZ31 Magnesium Alloy
CHU Ya-jie1,2, LI Xiao-quan1, WU Shen-qing2, XU Zhen-qin1, DU Shun-yao1
1. School of Material Engineering, Nanjing Institute of Technology, Nanjing 211167, China;
2. School of Material Science and Engineering, South East University, Nanjing 211189, China
Abstract:AZ31 magnesium alloy sheets were welded by manual TIG (tungsten insert gas) welding method with the same welding wire as filler material. The welded joints were compressed at 250,300,350,400℃ and strain rates of 0.001s-1 by a vacuum hot pressing furnace and a specially designed mold clamp. Microstructures and mechanical properties of welded joints with hot compression were analyzed by tensile test, optical metallographic microstructure (OM), scanning electronic microscopy (SEM). The results show that the tensile strength and elongation of the welded joint increase with the increasing temperature of hot compressing. The welded joint show the maximum tensile strength of 228MPa and elongation of 10.2% at 350℃, but lower at 400℃. The recrystallization phenomenon of joint is more and more obvious with the increasing deformation temperature in the process. Many dynamic recrystallization cores and small grains appear at 350℃ and the average grain size decreases from about 46μm to 16μm. As the temperature increases, the number of dynamic recrystallization grain is gradually increased. The grain size has grown up at 400℃, the average grain size is 26μm and evenly distributed.
初雅杰, 李晓泉, 吴申庆, 徐振钦, 杜舜尧. 热压形变参数对AZ31镁合金接头微观组织和力学性能的影响[J]. 材料工程, 2014, 0(6): 35-39.
CHU Ya-jie, LI Xiao-quan, WU Shen-qing, XU Zhen-qin, DU Shun-yao. Influence of Hot Compression Deformation on Microstructures and Mechanical Properties of Welded Joints for AZ31 Magnesium Alloy. Journal of Materials Engineering, 2014, 0(6): 35-39.
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