ZHAO Yunfeng, HUO Qiaoying, TENG Dongping, et al. Microstructure and mechanical properties of CMT joints for AZ31B magnesium alloy[J]. Eletric Welding Machine2018, 48(7): 31-35.DOI:
AZ31B镁合金CMT焊接接头组织与力学性能
摘要
对厚度3 mm的挤压态AZ31B镁合金板材进行CMT对焊
焊接工艺参数为:直径1.6 mm WE-33M焊丝、送丝速度6 m/min、焊接电流76 A、焊接速度0.8 m/min、焊缝间隙1.5 mm
3 mm thick AZ31B magnesium plates are butt welded by CMT technology. The welding parameters:1.6 mm diameter WE-33M feed wire
welding current of 76 A
wire feed rate of 6 m/min
welding speed of 0.8 m/min
weld interval of 1.5 mm. The welding process is stable without spatters and appearance of the weld is fine. The microstructure
microhardness
mechanical properties and tensile fracture appearance of welded joints are observed. The results show that grains in the weld microstructure are refined
the microhardness of the weld zone is the highest
and the average is 86 HV
the microhardness of HAZ is about 62 HV
the base metal about 65 HV. The maximum tensile strength and elongation of welded joint is 248.8 MPa and 7.16% respectively
which are 96.7%and 98.6% of the base metal respectively. The fracture is located in the base metal zone and belongs to ductile fracture.