Corrosion and repassivation of Super 13Cr stainless steel in artificial 1D pit electrodes at elevated temperature

Repassivation behavior of Super 13Cr martensitic stainless steel was investigated using a one-dimensional artificial pit electrode in deaerated NaCl solutions at 85 degrees C. Critical potentials for pit repassivation (E-crit) were measured by downward potential scans. E-crit and the final current density (i(f)) at the end of the scan can be correlated to the pit repassivation, showing that repassivation is more probable with smaller i(f) and higher E-crit. Pit repassivation at a constant potential was correlated with if and average current density (i(avg)). A combination of lower i(f) and i(avg) suggests a higher probability for pit repassivation.