The wetting behavior of Al/Sn under ultrasonic action

In order to create a reliable soldering joint, the wetting behavior of the Al/Sn system subjected to ultrasonic action was quantitatively investigated utilizing a wetting equilibrium experiment. After the wetting experiment, the samples' interfacial microstructure was observed, and it was also described how ultrasonic vibration affects the wettability of the non-reactive Al/Sn system. The wetting angle dropped from 134.76° to 75.9° after the sample had been subjected to ultrasonic action for 10 s, and the liquid solder rose along the unwetted Al base metal. The oxide deposit on the base metal surface was then gradually removed by ultrasonic cavitation at the contact interface between the liquid solder and the base metal, improving the wettability of the Al/Sn system. Once the oxide films on the surface of the Al base metal has been completely removed, the wetting force no longer increases when the ultrasonic vibration period is extended. Additionally, ultrasonic cavitation can significantly speed up the dissolving of Al into liquid Sn solder. But the effect of dissolution of base metal on the enhancement of wettability is constrained. wetting force won't rise significantly as dissolution increases.