LAUSR

Abstract Corrosion behavior of Sn-3.0Ag-0.5Cu lead-free solder alloy under chlorine-containing thin electrolyte layers is studied. The emphasis is laid on discussion about influences of addition of alloying elements, concentration of chloride ion and thickness of electrolyte layer on its corrosion behavior. Results indicate that: mainly local corrosion occurs to the alloy; Existence of intermetallic compounds and β-Sn crystal boundary facilitates the process of Cl− infiltration into the base and galvanic corrosion. Metal ions are accumulated in pitting corrosion region, and hydrolysis of metallic ions promotes the solution acidification and transverse development of pitting corrosion.