Effect of Minor Sb Additions on Thermal Properties, Microstructure and Microhardness of Sn–Ag–Cu High-Temperature Solder Alloys

In the present study, changes in thermal properties, microstructure and microhardness were investigated when 0.5, 1, 1.5 wt % Sb were added to Sn–1 wt % Ag–0.5 wt % Cu (SAC105) solder alloy system. The addition of Sb caused a significant improvement in microhardness while decreasing the melting temperature range, thermal conductivity and electrical conductivity. Addition of 0.5, 1, 1.5 wt % Sb to SAC105 alloy system decreased the thermal conductivity by 48% and electrical conductivity by 27%. The addition of Sb at the same rate increased the microhardness by 27%.