Tribological performance and molten zinc corrosion behavior of WC-CoCrFeNi cemented carbides

In zinc smelting, the die casting, and hot-dip galvanizing industries, roll materials are frequently subjected to prolonged exposure to molten zinc, which significantly deteriorates their service life. Consequently, the development of novel molten zinc-corrosion-resistant materials has become an urgent requirement for the hot-dip galvanizing industry. In this work, WC-based cemented carbides were fabricated via rapid hot-pressing sintering using CoCrFeNi high-entropy alloy (HEA) as the binder phase and WC as the hard phase. The microstructure was examined and described utilizing scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Additionally, a comprehensive investigation was conducted to determine the impact of CoCrFeNi high-entropy alloy (HEA) binder content on the mechanical properties, wear resistance, and corrosion resistance of WC-CoCrFeNi cemented carbides. The results demonstrated that the WC-HEA cemented carbide achieved the optimal comprehensive performance when the HEA binder content reached 10 wt%: At this content, the densification effect reduced the porosity and enhanced the interfacial bonding strength, resulting in the highest hardness (1965.2 HV) and fracture toughness (10.58 MPa·m^1/2). The appropriate HEA content provided a lubricating effect, leading to the lowest friction coefficient (0.267), and the improved thermal stability contributed to the best corrosion resistance to molten zinc (corrosion rate: 1.827 × 10⁻³ mm/h).