Fabrication of diamond–SiC–TiC composite by a spark plasma sintering-reactive synthesis method

Diamond–SiC–TiC composites were fabricated by a spark plasma sintering method which reduced the chance of graphitization of diamond due to its short sintering time. Ti and Si powder were used to consume the graphite occurred in the sintering process which reacted with C generating SiC and TiC chemically bonded diamond composites. The results suggested that no graphite phase presented in the composites sintered at 1200–1650 °C. Both bending strengths and relative densities of the composites increased along with the sintering temperature, and achieved up to 829 MPa and 99%, respectively, when the composites were sintered at 1650 °C for 10 min. Graphite emerged as a separate phase in the composites which were sintered at 1700 °C for 10 min, leading to the rapid decrease of the bending strengths and the relative densities.