Abstract：The dynamic compression test was carried out for rolled AZ31 magnesium alloy welding joint of argon tungsten-arc welding (TIG) and friction stir welding (FSW) with the split Hopkinson pressure bar at the strain rates of 900-2500s-1. The microstructure and fracture mechanism of the specimens were analyzed by scanning electron microscope (SEM) and optical microscope. The results show that with the increasing of the strain rate, the true stress-strain curves of AZ31 magnesium alloy welding joint have little change, implying the stress of AZ31 welding joints is not sensitive to the strain rate. The strength and plasticity of FSW joint are better than those of TIG joint under high strain rate. The fracture mode of AZ31 welding joints is cleavage under high strain rate, but compared to TIG joint, the FSW joint fracture is more smooth. The deformation microstructure analysis demonstrates that the microstructure is not sensitive to the strain rate, and the deformation mechanism of AZ31 welding joints is slipping under high stain rate compression.
毛萍莉, 席通, 刘正, 董阳, 刘遵鑫, 邸金南. 高应变率下AZ31镁合金焊接接头动态力学性能[J]. 材料工程, 2014, 0(5): 53-58.
MAO Ping-li, XI Tong, LIU Zheng, DONG Yang, LIU Zun-xin, DI Jin-nan. Dynamic Mechanical Property of AZ31 Magnesium Alloy Welding Joint Under High Strain Rate. Journal of Materials Engineering, 2014, 0(5): 53-58.
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