Enhancing the Corrosion Resistance of High Manganese Steel Through Controlled Chromium Additions
摘要
This study investigates the effect of controlled chromium (Cr) additions on the microstructure, corrosion resistance, hardness, and wear behavior of high manganese steel containing approximately 11 wt.% Mn and 1.1 wt.% C. Samples were prepared by induction melting and subjected to solution annealing at 1100 °C, followed by water quenching. The material was thoroughly characterized using a range of techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical corrosion analysis, hardness testing, and resistance evaluation. X-ray diffraction (XRD) analysis confirmed a fully austenitic single-phase structure in all samples, with no formation of martensite or cementite due to the stabilizing effect of high manganese and carbon content. Electrochemical testing in artificial saliva (AS) revealed that the sample containing 1 wt.% Cr exhibited the best corrosion resistance, attributed to the formation of a protective Cr2O3 passive film. However, higher Cr content (1.4 wt.%) resulted in slightly reduced corrosion performance due to microstructural defects observed via scanning electron microscopy (SEM). Hardness measurements showed the highest value in the Cr-free sample due to the presence of a needle-like cementite network, while Cr addition led to spheroidized carbides within the austenite grains. Wear resistance followed a similar trend, with the 1.4% Cr sample demonstrating performance comparable to the Cr-free sample, owing to finely dispersed chromium-rich carbides. The results suggest that an optimal Cr addition of ~1 wt.% enhances corrosion resistance without significantly compromising mechanical performance. These findings support the development of advanced high manganese steels for structural and biomedical applications where a balance between mechanical integrity and corrosion resistance is required.