The Cu/Sn63-Pb37 galvanic couple appeared in most electronic devices. the corrosion characteristics and mechanisms of this couple, which was exposed This paper was in the typically to investigate simulated air condition at 40 ℃ with 95% RH. The in-situ electrochemical information of the couple have been performed with related zero resistance ampere techniques under thin moisture film. According to the time dependent features of galvanic potential and anodic galvanic current density results, the Cu acted as anode and the Sn63-Pb37 acted as cathode during exposure. The gradually formed corrosion products, which were detected by FY-IR and XRD, restrained the anodic polarization behavior occurring on Cu surface. The hydrolyzed C02 on the Sn63-Pb37 sur- face induced the breakdown of Pb oxides formed in air naturally, which was confirmed from the SEM surface morphologies. Despite of the exact corrosion rates not obtained from the galvanic current density data, the chang- ing trend was valuable for estimating the atmospheric corrosion behavior of the Cu/Sn63-Pb37 couple.
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