Studies of Corrosion Kinetics on Electrical Contact Materials by Means of Quartz Crystal Microbalance and XPS

Abstract

Quartz crystal microbalance combined with x‐ray photoelectron spectroscopy has been used to study thin corrosion films of electroplated Ni and electroplated Sn or Au on Ni, with Sn‐ and Au‐thicknesses within the range used for electrical contact materials. Results are presented which show that mass changes can be measured in situ during corrosion at atmospheric pressure conditions. Based on quartz crystal microbalance measurements, the influence of and on the kinetics of atmospheric corrosion has been investigated. Introduction of sub‐ppm concentrations of or alone results in a minor increase in corrosion rates on Ni‐coated surfaces and in no significant increase in corrosion rates on Sn‐coated surfaces. Introduction of the same concentration of and simultaneously, however, results in significant increases in corrosion rates on all Ni‐, Sn‐, as well as Au‐coated surfaces.