SUN Jiashuai, ZHANG Yan, LING Diying, et al. Influence of wire feed speed on properties of 5083 aluminum alloy welded joint by plasma-MIG hybrid welding[J]. 2021,51(10):143-147. DOI： 10.7512/j.issn.1001-2303.2021.10.24.
Plasma-MIG hybrid welding was carried out on 5 mm thick 5083 aluminum alloy. The influence of wire feed speed on the weld appearance and properties of welded joints were studied. The microstructure of the joint was analyzed and the mechanical properties of the joint were tested. The results show that both wire feed speeds can obtain welded joints without obvious defects, and the reinforcement increases slightly when the wire feed speed improves. The dendrites in the weld zone of welded joints with wire feed speed of 9 m/min are smaller than those with wire feed speed of 7 m/min. The microhardness distribution of the welded joint is "W" shaped. The average hardness of weld zone and bond are lower than that of the base metal. The minimum hardness occurs in the bond that is 3 ～4 mm distant from the weld center. When the wire feed speed is 7 m/min, the joint softening is more obvious. Both tensile fractures of the joints at these two wire feed speeds occur near the bond. The tensile strength and elongation of welded joints at wire feed speed of 9 m/min are higher than those at 7 m/min.The fracture form is a typical toughness fracture.