Mechanical Property and Stress Corrosion Property of 5083 Aluminum Alloy Friction Stir Welding Joint

The butt welding of 4 mm thick 5083 aluminum alloy plate was carried out by using friction stir welding(FSW), and the microstructure, mechanical properties, residual stress and stress corrosion property of the 5083 aluminum alloy FSW joint were studied. The results show that the microstructure of the nugget zone of the welded joint is equiaxed grains, and the structure of the heat mechanical affected zone is deformed in a large extent, with obvious directionality. The tensile strength of the welded joint is 286.2 MPa, reaching 90.7% of the base metal. The hardness of the weld nugget zone is 83.2 HV, which is slightly lower than that of the base metal, and the hardness of the heat affected zone is the lowest. The longitudinal residual stress perpendicular to the direction of the weld seam in cross section shows the characteristics of bimodality. The stress corrosion sensitivity index I_SSRT value of the welded joint is 0.108, and the stress corrosion sensitivity is low.