Corrosion behavior of Sn-based lead-free solder alloys: a review

Sn-based lead-free solder alloys have been investigated widely to replace the traditional Sn–Pb solder alloys. Since the miniaturization of electronic products and the expansion of application field, the corrosion resistance of solder alloys play a key factor in the reliability of electronic products in long-term service. In this article, we review the recent progress on the corrosion behavior of Sn-based lead-free solder alloys by summarizing the results in representative ones of Sn–Bi, Sn–Cu, Sn–Zn, Sn–Ag, Sn–Ag–Cu and other multi-elements lead-free solder alloys. Specifically, the relationship between microstructure morphology and corrosion behavior, the corrosion mechanism of Sn-based lead-free solder alloys after incorporation of alloy elements or particles are summarized. It is hoped that this overview will provide some useful information in clarifying the corrosion mechanism and development of lead-free solder alloys. Furthermore, remaining difficulties and future trends in this research field are proposed.