The objective was to generate knowledge about the effects of the corrosion induced changes of the surface on the corrosion and electrochemical kinetics of carbon steels and pure iron exposed to aqueous C02 solutions. Besides its fundamental interest, the knowledge is needed for the development of better steels and for working out better models for the prediction of C02 corrosion of carbon steel exposed to the corrosive water phase from oil wells. The exposures were carried out at
25 to 10O°C with CO2 partial pressure of 0.65 to 3.2 bar. The paper
discusses the fundamentals of the anodic and cathodic reactions and the consequences of the formation of corrosion films of Fe3C and FeCO. Effects of microstructure and chromium additions to the steel are taken up. The influence of very small concentrations of sulfide ions...
Keywords: Corrosion, carbon dioxide, carbon steel electrochemistry, surface.