Characteristics of YAG-MIG hybrid welding 6061 Aluminum alloy with different states

摘要

With the diversification of manufacture methods, joining the same materials with different states becomes indispensable in practical application. The hybrid welding has broad application prospects. It not only reduces the strict assembled gap before welding, but also improves the joint properties by filling wire during the welding process. 6061 aluminum alloys with different states were welded by YAG-MIG hybrid welding. The characteristics of welded joint, including microstructures, the tensile properties, microhardness and fracture, were investigated. The results show that the microstructures are different significantly in different states. Besides, the grain boundaries of the joint microstructures become unclear after heat treating. The strength and the elongations of welded joints could reach to that of the base metal. The tensile fracture occurs in the fusion zone and near 6061-O alloy. And the fracture presents ductile rupture. Meanwhile, the effect of the small pores in the weld on the joint's tensile properties is slight.