In situ reaction synthesis of Ti–TiB composites containing high volume fraction of TiB by spark plasma sintering process

The in situ toughened Ti–TiB ceramic–matrix composites containing high volume fraction of TiB were synthesized by spark plasma sintering technique under a pressure of 50 MPa, with sintering temperature ranging from 1100 °C to 1400 °C and heating rate of 150 °C/min, using Ti and TiB2 powders. Results indicated that Ti–TiB composites sintered at 1400 °C provided the optimal combination of dense microstructure, well developed lath-shaped TiB grains, and excellent mechanical properties, including the relative density of 99.6%, bending strength of 608 MPa, and a rather high fracture toughness of 9.35 MPa m1/2. Moreover, the micro-hardness of the composites reaches a relatively high level (18.3 GPa).