On the joint strength and the structure of bonding interface in friction welding of aluminum alloy pipe to S25C carbon steel pipe

摘要

Friction welding of various aluminum alloy pipes to S25C carbon steel pipe were carried out to make clear weldability of dissimilar material pipes. Joints of A1050, A6061, and A6063 to S25C, and of A5052 and A5056 to S25C showed good weldabilityand medium weldability respectively, and the maximum joint efficiencies of these joints in tensile test were about 85%, 83%. 91%, 68% and 44%. In these joints, a intermetallic compound of All3Fe4 was formed at the weld interface of these joints. On theother hand, the joints of A2011, A2017, A2024, and A7075 to S25C showed poor weldability, and the maximum joint efficiencies of these joints were about 17%, 27% 17% and 39%. In these joints, CuAl{sub}2 and Al-Cu-Fe intermatallic compounds were observed at the weld interface because of these aluminum base alloy contained much copper. Therefore, it was supposed that the formation of intermetallic compounds based on Cu deteriorated the weldability of A2000 group and A7075 to S25C.