Electrochemical Corrosion Behavior and Mechanism of X80 Steel in the Aqueous Solution of Carbon Dioxide

The corrosion environment in oil produced water was simulated in the solution saturated with CO2, and the electrochemical corrosion behavior of X80 steel and the reaction mechanisms in anode and cathode at 60 ℃ were studied by means of electrochemical impendence spectroscopy(EIS) and potentialydynamic polarization curve. The effects of corrosion product film on the corrosion behavior and the corrosion reaction mechanism were monitored. The results showed that the anodic reactions obey Bockris mechanism, the predominant cathodic reaction is the reduction of carbonic acid, the competition between the deposition of corrosion product and the adsorption of reaction intermediate product influences the corrosion behavior of X80 steel and leads to the variation of EIS with corrosion time. The corrosion product film prevents X80 steel from further corrosion.