Research on the TIG welding process of wrought magnesium alloy

TIG welding process parameters of wrought magnesium alloy are discussed.The microstructure,mechanical property and pattern of fracture of welding joints are investigated by the metallographic microscope,microhardness instrument,cupping machine and scanning electronic microscope(SEM).The experimental results show that when the welding electric current is 80 A,the welding joint has a better shape.There are fine equiaxed grains in the welding seam and coarse grains in the heat-affected zone(HAZ).The hardness of the welding seam increases for the fine grain,while decreases in the HAZ.Tensile test results show that the mechanical property of the welding seam is inferior to that of the base metal,whose tensile strength is about 75% of the base mental.Analysis of the pattern of tensile fracture indicates that the fracture is tough-crisp.