1991 Volume 31 Issue 2 Pages 210-215
The effects of chlorination on the localized corrosion of stainless steel in saline environments have been studied by probing the detailed electrochemical environments with growing pits formed on UNS S30100, using micro-electrodes to determine the local pH, chloride ion concentration and potential.
In chlorinated systems, the reduction of free chlorine is the major cathodic electrode process. The strong reduction tendency of the free chlorine species increases the free corrosion potential of a steel. A model of chlorination-enhanced localized corrosion of stainless steels is proposed, wherein the growth of pits and crevices is influenced by the reduction of chlorine oxidant stimulated by the low local pH associated with sites of localized attack.