Interface Microstructure and Mechanical Properties of Aluminum/Copper Stud Welds

Abstract

It is known that it is difficult to bond dissmilar metals such as the aluminum and copper using diffusion bonding, because an intermetallic compound is easily produced in the bond interface. CD stud welding is suitable for welding of the bolt to the sheet without weld-marks on the back side of the weld. In this study, we performed stud-welding of bolts made of copper to an aluminum plate and investigated its weldability. The mixed layers were formed by melting of aluminum and copper at welded zone between the aluminum plate and the copper stud bolt. Tensile fractures of the stud welds were occurred in the intermetallic compound and/or the interface between the intermetallic compound and the mixed layer. High weld strength of 2.51 kN was obtained in case of capacitor capacity of 18.8 mF and charging voltage of 140 V.