Analysis and Comparison of Microstructure and Properties of 2Cr13 Stainless Steel and Its Laser Hardened Layer

The stainless steel 2Cr13 for steam turbine blades was surface-hardened with a semiconductor laser. Characterization and analysis of the microstructure, phase transformation, microhardness and wear resistance of the quenched layer were carried out. The results showed that after laser quenching of 2Cr13 stainless steel, the corrosion resistance of the substrate to the quenched layer gradually increased, and the microhardness increased from the substrate to the quenched layer in a longitudinal direction. The maximum microhardness was 713.1 HV_0.2, which was 3.24 times that of 2Cr13 stainless steel. The depth of the impact pit of the quenching layer was about 62 μm and the diameter was about 4.9 mm, while the depth of the impact pit of the base 2Cr13 was about 85 μm and the diameter was about 5.6 mm. Under the same impact work condition, the impact toughness of the quenching layer was higher than that of the substrate. The wear resistance of the quenched layer was 54.3 times that of the base 2Cr13 stainless steel. The wear mechanism of the quenched layer is mainly micro-ploughing and adhesive wear. The stainless steel 2Cr13for laser quenching hydraulic turbine could significantly improve the wear resistance of the substrate, and had a wide application prospect.