Dissimilar Joining of Aluminum to Copper Using Ultrasonic Welding

Abstract

Joint of aluminum to copper sheets with an Al2219 particle interlayer was successfully achieved by ultrasonic spot welding (USW). Effects of clamping pressure and surface activation on the microstructure and mechanical performances of the joints were systematically studied. It turned out that the optimal clamping pressure is 60 psi, and surface activation is beneficial to obtain a sound joint. On combining the actions of optimal clamping pressure and surface activation, the interfacial combination was highly intimate, and more plastic deformation occurred in the weld interface. Appropriate clamping pressure (30–60 psi) was beneficial to the weld interface bonding, whereas beyond the critical value (60 psi) aluminum beneath the sonotrode tip would be squeezed out of the weld interface.

Keywords:

• Interface
• Microstructure
• Ultrasonic
• Welding