Corrosion Through Porous Gold Plate

The corrosion of base metals through porous gold plate adversely effects the reliability of electronic connectors. Little is known, however, of these corrosion mechanisms, especially with gold-plated nickel. Previous work had been concerned almost exclusively with sulfide tarnishing of gold-plated silver or copper. This paper considers the corrosion of gold-plated nickel in environments containing sulfur dioxide, and relates the morphology of the corrosion deposits to electrical contact behavior. In contrast to the spreading of thin sulfide films over gold-plated silver, the nickel salts are present mainly as discrete mounds, localized at the pore sites. The importance of humidity was determined and explained on the basis of the galvanic mechanism of S0
2
-induced corrosion.