Synthesis and properties of hot pressed B4C–TiB2 ceramic composite

In order to improve the fracture toughness of B4C ceramics, B4C–TiB2 composite was prepared by hot pressing using B4C, C and TiCl4 as starting materials. The precursor powders of Ti(OH)4 and B4C were obtained using co-precipitation method. The phases, mechanical properties and microstructures of the B4C–TiB2 composite were investigated. The results showed that Ti(OH)4 almost converted into rutile TiO2 phase at 573 K for 1 h. The B4C–TiB2 composite with 43 mass% TiB2 showed the optimized mechanical properties. The optimum relative density, hardness, flexural strength and fracture toughness were 99.8%, 23.6 GPa, 506 MPa and 9.4 MPa m1/2, respectively. A number of twins and nanosecond-phase particles were observed in the B4C–TiB2 composite.