Effect of line energy on properties of aluminum alloy joints in double pulsed MIG welding

1060-T6 aluminum alloy butt joints were obtained by double pulsed MIG welding technique. Effcet of line energy on welding process, the microstructures and mechanical properties of the joints were investigated. The results showed that the welding process of double pulsed MIG welding was stable with little spatter, and the weld appeared as beautiful fish scale, within a certain range of line energy. For lower line energy, the tensile strength of joint was lower because of incomplete fusion and gas pores. With an increase in line energy, the width of the heat-aected zone increased and grains in the fusion zone coarsened. Moreover, incomplete fusion and gas pores were gradually decreased, which was obviously improved the tensile strength of joint.