Ultrasonic-assisted soldering of fine-grained 7034 aluminum alloy using Sn-Zn solders below 300°C.

The fine-grained Al alloys prefer to be soldered at as low as temperature to keep their mechanical properties. Solders of Sn-4Zn, Sn-9Zn, and Sn-20Zn alloys were used to solder fine-grained 7034 Al alloy pieces by ultrasonic-assisted soldering below 300°C in air. The joint using Sn-4Zn solder had the highest tensile strength of 201MPa and the fractures occurred in both β-Sn and Sn-Zn eutectic phases.

Ultrasonic-promoted rapid TLP bonding of fine-grained 7034 high strength aluminum alloys.

High strength aluminum alloys are extremely sensitive to the thermal cycle of welding. An ultrasonic-promoted rapid TLP bonding with an interlayer of pure Zn was developed to join fine-grained 7034 aluminum alloys at the temperature of lower 400°C. The oxide film could be successfully removed with the ultrasonic vibration, and the Al-Zn eutectic liquid phase generated once Al and Zn contacted with each other.