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In order to solve the problem of slow reaction rate and particle growth in hydrogen-free carbonization, a amount of Pt (0.01 wt%) was added as catalyst in the carbonization process to improve the reaction rate and prepare nano WC powder.The binderless tungsten carbide was produced by hot press sintering (HPS) at 1400-1800 ℃ with an applied pressure of 40 MPa.The effects of Pt addition on the sintering performance and microstructure WC powder and the effects of Pt addition and the sintering temperature on the densification, microstructure and mechanical properties of the sintered sample were investigated.The results show that a amount of Pt (0.01 wt%) can significantly reduce the temperature of hydrogen-free carbonization, and the prepared WC powder has a fine and uniform particle size.As the sintering temperature increases, the density of binderless tungsten carbide increases, the grain size increases, and the hardness and fracture toughness increase. However, when the sintering temperature is too high, resulting in abnormal growth grains and W₂C phase, which leads to a serious decline in the fracture toughness of binderless tungsten carbide. When the sintering tempertuare was 1700 ℃, the hardness and fracture toughness reached the maximum walues of 2887 kg.mm^_-2 and 7.1 MPa.mm^_1/2, respectively.