Microstructure and Wear Behavior of High-Cr WCI Matrix Surface Composite Reinforced with Cemented Carbide Rods

The present article reports a new superior wear resistance surface composite prepared by a vacuum evaporative pattern casting-in process. This surface composite was constructed with reinforcing cemented carbide rod (CCR) array within high-Cr white cast iron (WCI) matrix. Three reaction zones that formed around the CCRs were characterized and established the good metallurgical bonding between CCRs and matrix. In addition, some compound carbide containing Fe, Cr, W, and Co elements were formed in the reaction zones, owing to the partial dissolution of the CCRs and the resulting interdiffusion of elements such as W, Co, C, Fe, and Cr. The wear behavior of the composite was evaluated and compared with unreinforced high-Cr WCI by means of a three-body abrasive wear tester. The results showed that the wear resistance of the composite was significantly higher than that of the unreinforced high-Cr WCI. The exciting wear resistance can be ascribed to protective effect introduced by the CCRs during wear process and the good metallurgical bonding between CCRs and matrix.