ATMOSPHERIC CORROSION OF COBALT

Cobalt atmospheric corrosion is discussed, ranging from nucleation of water to observed indoor corrosion rates. The air-exposed surfaces of cobalt are shown to be complex oxyhydroxides. Significant quantities of water are adsorbed on this surface. The initial stage of corrosion in a polluted environment is shown to be very heterogeneous. Corrosion kinetics for cobalt are linear and are exponentially dependent on relative humidity. The partial pressures of SO2, CI2, and NH3 significantly influence cobalt corrosion while H2S, NO2, and O3 show little effect. Cobalt corrodes in indoor environments at rates similar to nickel and follows log normal statistics over the field site population studied. © 1979, The Electrochemical Society, Inc. All rights reserved.