The crevice corrosion behavior of N80 carbon steel in acidic NaCl solution: The effect of O2

The effect of O2 on crevice corrosion of N80 carbon steel in acidic NaCl solution is investigated. Crevice corrosion of N80 carbon steel could be initiated with or without O2 in acidic NaCl solution. A deep corrosion groove could be formed near the crevice mouth after crevice corrosion. The crevice corrosion of N80 carbon steel is ascribed to the increased pH inside the crevice in acidic NaCl solution. The presence of O2 in the solution could enhance the cathodic reaction processes outside the crevice, but it is not significant for the cathodic reaction processes inside the crevice. The galvanic corrosion effect between inner and outer steels could be enhanced by O2 and then promote crevice corrosion.