Investigations of the wetting behaviors of Zn–25Sn, Zn–25Sn–XPr and Zn–25Sn–YAl high temperature lead free solders in air and Ar ambient

Abstract Zn–25Sn based alloys possess great potential as candidates for high temperature lead-free solders. But it exhibits poor oxidation resistance due to the high Zinc content. This study selected Pr (0.01–0.08 wt%) and Al (0.01–0.25 wt%) as alloying elements to improve the wetting performance of Zn–25Sn based solder alloy. It was found that the addition of 0.01 wt% Pr increased the wetting force. However, dewetting was observed under air atmosphere for the Zn–25Sn, Pr-containing solder, and solder containing 0.01% Al. It was also be found that the dewetting of Pr-containing solder could be avoided under argon atmosphere as well as with higher Al addition.