Effects of Sb addition on tensile strength of Sn–3.5Ag–0.7Cu solder alloy and joint

This work investigates the effects of Sb on the tensile property of the Sn–3.5Ag–0.7Cu lead-free solder alloy and joints. Results show that the Sb-containing solder alloys and joints have higher ultimate tensile strength (UTS) than Sb-free solder alloy and solder joints due to solid solution hardening and particle hardening. UTS of solder alloys have a logarithmic increase relation with strain rate and decreases with the increase of testing temperature. The tensile strength of Sn–3.5Ag–0.7Cu solder joint reaches the highest value when 1.0 wt.% Sb is added and drops with the ageing time due to intermetallic compounds (IMC) growth at solder/IMC interface.