Effect of Temperature on Electrochemical Corrosion Behavior of 316L Stainless Steel in Borate Buffer Solution

The effects of temperture on the electrochemical corrosion behaviors of 316L stainless steel in borate buffer solution were investigated by dynamic polarization and electrochemical impedance spectroscopy (EIS). Mott-Schottky curves were used to study the semiconductor characters of the passive film .The results showed that a stable passive film formed on 316L stainless steel surface in the range from 35 ℃ to 85 ℃. It was found that corrosion mechanism was not changed with the increase of solution temperature, but the anodic process was promoted and the corrosion rate increased. The polarization resistance decreased with the solution temperature increase. The result of Mott-Schottky curves showed that there was little effect of temperature on the semiconductor characters of passive film. The passive film was a n-type semiconductor in the range of -0.3 V to 0.3 V (SCE) and it was p-type semiconductor in the 0.3 V to 1.5 V (SCE). The donor density (NS) and acceptor density (ND) increased with increasing the temperature.