Influence of TiC content on microstructure and mechanical properties of (Ta, Ti)C ceramics

(Ta, Ti)C ceramics with different TiC contents have been fabricated by hot pressing using as-synthesized carbide powders via carbothermal reaction. The effect of TiC content on densification, microstructure and mechanical properties was investigated. All samples with adding TiC exhibit high relative density of >98%, and even the relative density can reach 99.6% when TiC content is 33 mol%. Besides enhancing sinterability, the average grain sizes of samples significantly become large in the range of 19.9–39.4 μm. (Ta0.83Ti0.17)C ceramic possesses an optimized combination of mechanical properties with a Vickers' hardness, flexural strength, Young's modulus and fracture toughness of 17.5 GPa, 306 MPa, 544 GPa and 3.7 MPa·m1/2, respectively.