Corrosion of Decorative Plating Systems Containing Cobalt

SummaryDecoratively plated panels, with intermediate duplex metal layers of nickel, cobalt, or alloys of nickel and cobalt, were corroded in mobile exposure or in the EC Test. Measurements of corrosion pits and values of pit densities (number per unit area) were obtained by microscopic techniques. The measurements of corrosion from panels having about equal values of pit densities were compared. Results showed that deposits of cobalt or alloys of nickel and cobalt were more corrodible than deposits of nickel without cobalt.