Significance of temperature change on the behavior of crevice corrosion

The role of temperature change on the stability of crevice corrosion in a commercially pure nickel was investigated in 1 N sulfuric acid (H2SO4). The crevice current and the potential gradient within the crevice were measured at 24, 45, and 70degreesC, for a crevice with both ends open and its mouth facing the electrolyte in a downward position. Experimentation demonstrated that the active/passive boundary, x(pass) moved closer to the crevice mouth while the crevice current rose sharply for increasing temperature. A large, steep potential drop of 589 mV on the crevice wall was measured at 70degreesC, when the potential at the surface, E-surf, was held ut 400 mV vs saturated calomel electrode (SCE). These findings were in close agreement with the IR voltage theory predictions.