부산대학교 도서관

In the past research, there was a gap in the field of Al/Cu dissimilar metal welding with Ag intermediate layer, and attention to the joint resistivity is insufficient. This paper has used laser welding to study this problem. The mechanical and electrical properties of the joints were tested, and the microstructure and fracture surface of the weld were observed, along with the analysis of their phase composition and formation mechanism. The results show that the Ag–Al–Cu ternary system forms on the weld, and Ag inhibits the formation of IMC in the Al/Cu system, with the main IMCs being Al2Cu and Ag3Al. Part of the Ag-rich and Al-rich phases are dispersed in small particle shape, providing a strengthening effect in various areas. After adjusting the welding parameters, excellent joints can be obtained, with a tensile strength of 98.05 MPa, which is 78.5% of the base metal, and a resistivity of 2.47 μΩ cm. The fracture occurs in the softened zone of the Al-side base metal, indicating a ductile fracture. These findings have demonstrated that good mechanical and electrical properties can be obtained by adding Ag as an intermediate layer of the joint.