Effect of chromium-induced (Fe, Cr)3C toughness improvement on the two-body abrasive wear behaviors of white cast iron

Abstract An as-cast chromium white cast iron alloy with chromium (Cr) content of 0 wt%, 1 wt%, 2 wt%, 3 wt%, and 4 wt% was prepared via metallurgical smelting and casting processes. The effects of Cr content on the toughness, hardness, and microstructure of (Fe, Cr)3C carbides was evaluated. The results revealed that the microstructure of the as-cast alloys is mainly composed of bulk carbide and the pearlite matrix. The carbide in the alloy without added Cr, i.e., eutectic Fe3C, was characterized by a continuous network structure. With the addition of Cr atoms, the Fe3C-type carbide was transformed into (Fe, Cr)3C, leading to a gradual increase in the fracture toughness of the carbide. This may have resulted from the incorporation of Cr into Fe3C and the consequent crystal-structure transformation of the carbide. When the Cr content of the carbide was lower than the saturation level (