Song-Chun Ri, Kyong-Sik Ju
In this study, a nitriding salt bath containing 1 wt% V2O5 was employed for treatment of carbon steel samples for several hours (20, 40, 60, 80, 100, 120 min) at a temperature of 500 ± 10 °C and the possibility for accelerating the nitriding process was examined. The microstructure, phase composition, micro-hardness and wear resistance for the non-nitrided and nitrided samples were evaluated through general characterization. The surface corrosion properties of nitrided samples were evaluated through neutral salt water spray test, electrochemical polarization test, and electrochemical impedance spectroscopy. Fe3C was not observed in the nitride layers composed of Fe3N and Fe4N in the range of 10-25 µm. The values of micro-hardness for the nitride layers were not linearly related to nitriding time, reaching a maximum of 627 HV0.1. The corrosion resistance of the nitrided samples with V2O5 was improved significantly compared to the untreated sample.