Effect of Temperature and Dissolved Oxygen on Corrosion Properties of 304 Stainless Steel in Seawater

Cyclic polarization technique and electrochemical impedance spectroscopy(EIS) were used to study the effect of temperature and dissolved oxygen(DO) on the corrosion properties of 304 stainless steel in seawater. The cyclic polarization results showed that the corrosion potential of stainless steel shifted in the positive direction slightly at different temperatures with the increase of dissovled oxygen concentration. The pitting potential became positive at 4 ℃ and negative with the increase of dissolved oxygen at 15 ℃. The pitting corrosion repair performance of 304 sinless steel decreased under the condition of 4 ℃, 7.5 mg/L DO and 15 ℃, 3.0 mg/L, 7.5 mg/L DO. Electrochemical impedance spectroscopy showed that EIS had a single capacitive loop during the experiment. With the increase of dissolved oxygen the stability of passive film decreased.