Corrosion resistance improvement in 6Cr13 martensitic stainless steel via quenching-tempering and partitioning

In this work, the effect of the temperature of quenching-tempering and partitioning on the corrosion resistance of 6Cr13 martensitic stainless steel was investigated by immersion test and electrochemical test. The results show that tempering and partitioning can improve the stability of the retained austenite at room temperature. The volume fraction of austenite increases with the increase of the temperature of tempering and partitioning. From the results of the corrosion experiment, the corrosion resistance of 6Cr13 martensitic stainless steel first increases with the increase of heat treatment temperature. The best corrosion resistance is obtained at 400 degrees C. Subsequently, the corrosion resistance decreased with the further increase in heat treatment temperature. The reason for the increase in corrosion resistance is that with the increase of heat treatment temperature, retained austenite's content gradually increases, enhancing the corrosion resistance. The decrease in corrosion resistance is related to the growth of retained austenite and carbide at high temperatures.