Effect of process parameters on weld quality during double-pulsed gas metal arc welding of dissimilar stainless steel

To solve the problem of welding process parameters are difficult to control on dissimilar stainless steel(2205 and 316L), the double-pulsed melting inert-gas welding (DP-MIG) was conducted on the 2205 duplex stainless steel and 316L stainless steel. The effects of the number of strong pulses, the number of weak pulses and the welding speed were studied. The electrical parameters in the welding process were collected through the wavelet analyzer. In addition, the mechanical tensile and metallographic tests were executed. The results demonstrated that the welding speed had the highest impact on the welding quality among all three factors, which was followed by the number of weak pulses and the number of strong pulses had the least impact. The welded seam obtained by various numbers of strong and weak pulses was relatively uniform, indicating that the effect of the number of strong and weak pulses on the welded seam was relatively low. The tensile fracture mainly occurred in the joint and the base material part of the 316L stainless steel. When the welding speed was increased, the heat input reduced during the welding of the welded seam, the cooling rate of the welded seam accelerated, whereas the ferrite transition duration reduced, which led to a relatively fine structure.