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_{:According to different sintering conditions and TiC/WC composition ratio, three-layer biomimetic composite ceramic tool materials were prepared by hot pressing sintering process. The mechanical properties of the biomi-metic composite ceramic materials were tested, and the fracture surface morphology and crack propagation were analyzed. The flexural strength, Vickers hardness and fracture toughness are 870 MPa, 21.83 GPa, and 7.56 MPa?m1/2, which is higher than that of SG4 homogeneous ceramic cutting tool material. Section morpholo-gies show that the bioimimetic composite ceramic material has finer microstructure than that of SG4 ceramic cuttin tool material, and the grain size shows multi-scale characteristic. Fracture surfaces demonstrate a trans-granular/intergranular mode. The crack propagation path of the surface layer shows crack deflection and bifur-cation of the crack tip.The crack is also deflected as crack passing through the bi-material interface.}