Corrosion behavior of carbon steel in chloride and bicarbonate ion‐enriched and CO2‐saturated solutions

Abstract This article addresses the knowledge gap in the area of the synergistic effect between Cl − and by comprehensively evaluating the corrosion behavior of AISI 1020 carbon steel exposed to the CO 2 ‐saturated solutions containing Cl − and/or over the time period of 6–72 hrs at 60°C. The results show a synergistic mechanism between Cl − and in the pitting corrosion of carbon steel. accelerates the localized precipitation of FeCO 3 crystals by means of increasing pH and adsorption, which is a prerequisite for pitting initiation. Cl − contributes to the catalytic dissolution of the Fe matrix along with film breakdown via the local accumulation of oxygen vacancies, and the pitting corrosion of carbon steel is, thus, further exacerbated.