Corrosion Behaviour of 2Cr13 Stainless Steel in CO₂-saturated NaCl Solution in Presence of Acetic Acid

The effect of acetic acid on corrosion behaviour of 2Cr13 stainless steel in CO2-saturated 3% NaCl solution at 60 ℃ was investigated by using polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). Corrosion mechanism was discussed. With the addition of acetic acid in the solution, both cathodic and anodic reaction rates increase remarkably. It is attributed to the fact that acetic acid adsorbed on electrode surface can be reduced directly by electrochemical reaction, and facilitate the formation and dissolution of ferrous carbonate due to the decrease of solution pH. Acetic acid enhances both localized corrosion and general corrosion attack on 2Cr13 stainless steel.