Influence of Zn content on properties of Cu/SAC0307+xZn/Al joint by ultrasonic-assisted at low-temperature

The ultrasonic assisted soldering joint of Cu/SAC0307+xZn powder /Al (x=0%, 10%, 20%, 30%, 40%) at low temperature was studied. In this study, SAC0307 particles of 25-38μm were used as the main solder, and zinc particles of 1μm was mixed as the final solder. The soldered was heated to 180 °C in environmental atmosphere under the ultrasonic-assisted, and bonding of Cu/Al was successfully achieved. The results show that a complete and continuous Cu 5 Zn 8 compound was formed at the Cu-side interface, and a solid solution was formed between the base metal and Zn at the aluminum side. In the absence of Zn, the shear strength of joints was only 2.44MPa. When the content of Zn was 30%, the Zn particles were bonded tightly with SAC particles under the action of ultrasound, and the shear strength of joints reached the maximum with 19.23MPa, which is 688.1% higher than that of the joint without Zn.