Sn-In-Ag phase equilibria and Sn-In-(Ag)/Ag interfacial reactions

► Thermodynamic models of Sn-In and Sn-In-Ag are developed using the CALPHAD approach. ► Reaction layer in the Sn-In-(Ag)/Ag couples at 100 °C is thinner than those at 25 °C, 50 °C, and 75 °C. ► Reactions in the Sn-20 wt%In-2.8 wt%Ag/Ag couples are faster than those in the Sn-20 wt%In/Ag couples.