Microstructure and Properties of NiFeCrBSi/WC Composite Coatings Fabricated by Vacuum Cladding

Resumo

Abstract—In this study, WC-reinforced Ni-based alloy composite coatings were fabricated on the surface of ASTM 1045 steel by vacuum cladding. The microstructure, hardness, and wear resistance of coatings with different tungsten carbide (WC) content and dissolution mechanisms for WC at different cladding temperatures were studied. The bonding phase was mainly composed of austenite (Ni_2.9Cr_0.7Fe_0.36, FeNi), and the reinforced phases consisted of WC, carbides (Cr₇C₃, (Cr,Fe)₇C₃), borides, and silicides. The dissolution of WC became severe with increasing cladding temperature, and the reaction products mainly included rounded block-shaped WC particles, lath-shaped rich tungsten carbide, and fine granular carbides. The Ni-based coating with 30% WC sintering at 1225°C performed better wear resistance, six times greater than that of matrix steel.