Effect of Cu Addition on Microstructure and Corrosion Resistance of GCr15 Steel

GCr15 steel was remelted by adding Cu with mass fraction of 0, 0.036%, 0.070% and 0.110% in a vacuum arc furnace. The effects of Cu addition on the microstructure, hardness and corrosion resistance were studied. The results show that adding Cu promoted the transformation from austenite to martensite. With the increase of Cu addition, the martensite structure was more and finer, the segregation degree of Cu increased, and the hardness of the steel increased. When the Cu addition was 0.036%, the self-corrosion potential was the highest, the corrosion tendency was the smallest, and the pitting pit was the smallest. When the Cu addition was 0.110%, the self-corrosion current density was the smallest, the corrosion rate was the slowest, and the pitting area was the smallest.