Effect of Chromium Content Change on Corrosion Resistance of Chromium-Manganese Steel

By means of weight-loss method, electrochemical polarization curve method, scanning electron microscopy (SEM) and X-ray diffraction (XRD), the effects of chromium content on the corrosion resistance of chromium-manganese steel and its mechanism in an acidic environment were studied, and the optimal chromium content was determined. The results show that when the mass fraction of chromium was in the range of 10%-15%, the Cr₂O₃ protective film forming on and adhering to the surface of chromium-manganese steel became denser and denser with the increase of chromium content, which played a protective role. However, increasing the chromium content continuously, the corrosion rate of chromium-manganese steel was almost unchanged, so the optimal chromium content in chromium-manganese steel was determined to be 14% (mass fraction).