High-performance binderless WC-ZrO2 cemented carbides were prepared via spark plasma sintering. Subsequently, the microstructure and properties of carbides with varying ZrO2 contents were investigated, focusing on their friction wear performance and wear mechanisms under different loads (40, 60, and 80 N) with Si3N4 as the counterbody material. The results indicated that the WC-10 wt% ZrO2 alloy exhibited optimal overall properties at a sintering temperature of 1650 °C, sintering pressure of 40 MPa, and holding time of 5 min. The relative density, Vickers hardness, and fracture toughness were 99.9%, 2054 HV, and 11.3 MPa·m1/2, respectively. Under an 80 N load, the steady-state friction coefficient decreased from 0.625 for pure WC to 0.326 for WC-10 wt% ZrO2. Further, the wear mechanisms in pure WC included abrasion, adhesion, and oxidation. The steady-state friction coefficients of the WC-10 wt% ZrO2 alloy under different loads ranged from 0.27 to 0.33, and the wear mark width and wear amount increased with an increase in load. Additionally, the wear mechanism changed with increasing load: abrasive wear was observed at 40 N, and a combination of abrasive and adhesive wear was observed at 80 N.
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