Effect of Heat Treatment on Intergranular Corrosion Susceptibility of 430 Stainless Steel Evaluated by Electrochemical Potentiodynamic Reactivation

The effects of heat treatment temperature, cooling method and holding time on the intergranular corrosion susceptibility of 430 stainless steel were studied by electrochemical potentiodynamic reactivation (EPR) combined with metallographic analysis. The results show that the sensitization of 430 stainless steel began to occur in the temperature range of 700-750℃. With the increase of heat treatment temperature, the grain gradually grew, the degree of sensitization and carbonitride precipitation position were affected by subsequent cooling method. When heat treatment temperature was 900℃, 430 stainless steel was sensitized in a short time, and the degree of sensitization of 430 stainless steel was not significantly reduced with the extension of holding time. Heat treatment for a short time at 700℃ and air cooling could effectively reduce the intergranular corrosion susceptibility of the sensitized 430 stainless steel.