Effects of nanoscale Cu6Sn5 particles addition on microstructure and properties of SnBi solder alloys

In this work, Cu6Sn5 nanoparticles in dimension of 10 nm are synthesized and first applied to improve the SnBi solder alloys. The microstructure, tensile properties, creep behavior and corrosion resistance of the composite solder are all investigated. Furthermore, solder with 0.05 wt% Cu6Sn5 nanoparticles presents the best performance among all the samples. Addition of Cu6Sn5 nanoparticles refines the microstructure of SnBi solder. Comparing with the pure sample, tensile properties of the composite one perform a brittle to ductile change. The nanoindentation test reveals that the creep resistance of SnBi-Cu6Sn5 samples is enhanced through the creep mechanism transformation. In corrosion experiments, samples with nanoparticles exhibit a lower corrosion rate. This reinforcement from nanoparticles of intermetallic compounds will provide us a new cognition in solder micro-alloying.