Influence of Heat Treatment Process on the Intergranular Corrosion Susceptibility of 304 Stainless Steel Evaluated by Electrochemical Potentiodynamic Reactivation Method

Electrochemical potentiodynamic reactivation (EPR) method was used to study the intergranular corrosion susceptibility of the 304 stainless steel under different heating temperature, holding time and cooling mode. The results show that:the EPR method could quantitatively evaluate the intergranular corrosion susceptibility of the 304 stainless steel; the sensitization would happen to the 304 stainless steel when the heat treatment temperature was 500-800℃, and the sensitization degree was highest at approximately 650℃; when the 304 stainless steel was heat treated at the temperature of above 650℃, rapid cooling could effectively reduce the sensitization degree of intergranular corrosion, but furnace cooling would increase its sensitization degree.