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Nano SiC particles dispersion strengthened WC-10Ni cemented carbide composites were fabricated by high energy ball milling(HEBM) and vacuum sintering(VS). The effects of the SiC content and vacuum sintering temperature on the microstructure and the room temperature mechanical properties of the SiC doped WC-10Ni cemented carbide composites were investigated in this paper. The results showed that the well-combined and highly-densified (nearly 99.2%) WC-10Ni-SiC composites can be obtained by the VS technology at 1 450 ℃ and 1 500 ℃, respectively. The addition of the SiC can not only restrain the growth of WC grains, but also play a role in refining grains, but also accelerate densification of the WC grains sintering. Also the vickers hardness of the prepared composite materials is improved with the increase of SiC content, up to 1 649 HV. Their fracture toughness and flexural strength increased with the increase of the SiC addition and then decreased. The fracture toughness and flexural strength of the WC-10Ni-SiC cemented carbide composites are 12.7 MPa?m_1/2 and 1 126.1 MPa, respectively when the content of the SiC is 0.5wt %.