2016 年 124 巻 4 号 p. 381-387
TaC–NbC with and without the addition of 5 vol.% B4C and 5 vol.% Si nano-powders as sintering aids were consolidated by spark plasma sintering at 1850°C. The effect of sintering aid addition on the densification and mechanical properties is evaluated along with secondary phase formations. Relative density >99% is achieved with a hold time of just 3 min for the addition of Si and 10 min for the addition of B4C as sintering additives. High load instrumented indentation was performed and projected area of residual damage is compared to estimate relative fracture toughness. The addition of 5 vol.% Si as a sintering additive resulted in a 46% reduction in projected residual damage area and 14.5% more energy dissipation during indentation than the sample with 5 vol.% B4C as the sintering additive resulting in a higher overall toughness.