Effect of Heat Treatment on Microstructure and Property of Cr13 Super Martensitic Stainless Steel

The microstructures and mechanical properties of Cr13 super martensitic stainless steel after different heat treatments were studied. The results show that the structures of the steel after quenching are of lath martensite mixed with a small amount of retained austenite. With the raising quenching temperature, the original austenite grain size increases and the lath martensite gradually becomes thicker. The structures of the tempered steel are mixtures of tempered martensite and reversed austenite dispersed in the martensite matrix. The amount of reversed austenite is from 7.54% to 22.49%. After different heat treatments, the tensile strength, the elongation and the HRC hardness of the steel are in the range of 813–1070 MPa, 10.1%–21.2% and 21.33–32.37, respectively. The steel displays the best comprehensive mechanical properties after the sample is quenched at 1050 °C followed by tempering at 650 °C.