Initial steps of corrosion in the steel/Ca(OH)2 + Cl− system: The role of heterogeneities on the steel surface and oxygen supply

The studies about localized corrosion usually involve determining the critical breakdown potential (E[sub b]). However, this procedure does not provide an accurate indication of the risk of pit corrosion occurring naturally, because in free corrosion conditions the necessary polarization to reach the breakdown potential is not applied externally, but it depends exclusively on the generation of some type of galvanic cell. The goal of this work was to determine under free corrosion conditions the factors that foster localized corrosion in the steel/Ca(OH)[sub 2] + Cl[sup [minus]] system. More specifically, the paper deals with the influence of the heterogeneities on the steel/solution interface, the dissolved oxygen and the presence of chloride ions.