Thermomechanical response of a lead-free solder reinforced with a shape memory alloy

In order to improve solder joint life, we have experimented with a lead-free solder reinforced with a NiTi shape memory alloy (SMA). Concept viability was evaluated by conducting thermomechanical double-shear tests on bare SMA wire and single-fiber composites of Sn–3.5Ag matrix reinforced with a single SMA wire. A copper wire reinforced composite served as the control sample. The results indicate that a significant reduction in inelastic strain range can be realized by the SMA composite approach, suggesting a possible payoff in the life of solder joints.