Theoretical Calculations and Experimental Study of the Nitrided Layer of 1Cr17Ni2 Steel

Due to the harsh operating conditions experienced by 1Cr17Ni2 steel, efforts were made to optimize its performance by subjecting 1Cr17Ni2 stainless steel to nitriding treatments at temperatures of 460 °C, 500 °C, and 550 °C, each for durations of 8 and 16 h. The formation state of its cross section was observed through a metallurgical microscope and scanning electron microscope, and it was characterized by hardness measurement. Through a ball-on-disk wear experiment, the adhesive wear and friction coefficient of its non-lubricated sliding were measured. The phase composition of its surface was measured by XRD. The results revealed that nitriding led to the formation of a modified layer on the surface of the samples, with a depth of 130 μm after nitriding at 550 °C for 16 h. The hardness of the modified layer exceeded that of the matrix, reaching up to 1400 Hv0.1. X-ray diffraction (XRD) analysis of the sample surfaces indicated the presence of high-hardness phases such as CrN, γ′-Fe4N, and ε-Fe2-3N. This article predicts the mechanical properties of nitrided phases in high-alloy martensitic stainless steel through first-principles computational methods. We provide a reference for improving the performance of high-alloy steel after nitriding through a combination of theoretical calculations and experiments.