Analysis and simulation of laser swing welding process for stainless steel stacked joints

In this study, the 304 stainless-steel sheet test with 1 mm + 1 mm is carried out by laser swing welding technology, simulating the welding process and performing molten pool calibration. Three process parameters, swing form, laser power, and welding speed, are combined to study the effects of different process parameters on surface morphology, joint macrostructure, and cross-sectional porosity. The results show that welding power and welding speed directly affect the heat input, which, in turn, affects molten pool morphology. By comparing the different swinging methods, it is obtained that the square swinging has a larger relative area, uniform heat input, little spatter, low porosity, and the best depth-to-width ratio obtained by molten pool molding, which is the best scanning method. In addition, when the welding power is 840 W and the welding speed is 10 mm/s, the weld depth-to-width ratio of four swing forms is greater than 0.95, and the microhardness is approximate “n”-type distribution. Through finite element simulation, it is concluded that the use of a Gaussian rotating body heat source is consistent with the actual situation, and the cross-sectional morphology of the weld seam is in the shape of a bowl.