Enhancement mechanical properties of in-situ preparated B4C-based composites with small amount of (Ti3SiC2+Si)

B4C-based composites were synthesized by spark plasma sintering using B4C?Ti3SiC2?Si as starting materials. The effects of sintering temperature and second phase content on mechanical performance and microstructure of composites were studied. Full dense B4C-based composites were obtained at a low sintering temperature of 1800 C. The B4C-based composite with 10 wt% (TiB2+SiC) shows excellent mechanical properties: the Vickers hardness, fracture toughness, and flexural strength are 33 GPa, 8 MPa m(1/2), 569 MPa, respectively. High hardness and flexural strength were attributed to the high relative density and grain refinement, the high fracture toughness was owing to the crack deflection and uniform distribution of the second phase.