Experimental study on laser welding lap joint of 321 stainless steel sheet

Abstract This paper conducts laser welding experiments on 1 mm thickness 321 stainless, designing an orthogonal experiment to analyze the relationship between parameters of welding power, welding speed, focal length adjustment, and property of joint. We determine the optimal parameters of the welding procedure: the welding power of 2, 150 W, the welding speed of 1, 200 mm/min, and the defocus of 8 mm. We conduct macroscopic, microscopic, ferrite, and shear force examinations on joints produced by optimal parameters of the welding procedure. The study findings indicate that the welds produced with optimized procedure parameters exhibit satisfactory shape, and the microstructure of the welded joint consists of Austenite+Ferrite. The shear strength of the joint complies with standard specifications and exhibits superior shear resistance compared to the parent material. The selected welding procedure is reasonable, and the joint performance meets the specified requirements.