Two-stage nonequilibrium eutectic transformation in a Sn–3.5Ag–3In solder

The nonequilibrium solidification of Sn–3.5Ag–3In and the microstructure thus produced were examined in this study. Results show that In was dissolved into Sn and Ag3Sn and reduced the melting temperature. In segregation during solidification led to an expanded melting range and a mixed normal–coarse structure with Sn and Ag3(Sn, In). This also resulted in a specific two-stage nonequilibrium eutectic solidification feature.