The lap welding of 304 stainless steel sheet by YAG pulsed laser welding and different heat treatment after welding were carried out, the effect of heat treatment process on microstructure, hardness and tensile strength of welded joint was analyzed.The experimental results show that the microstructure of weld center is equiaxed crystal, which is fine and uniform after solid solution treatment of 1000℃holding 60 min and water cooling. The edge of the weld is columnar crystal which is perpendicular to the fus...