ZrC Based Ceramics by High Pressure High Temperature SPS Technique

Abstract

Zirconium carbide based materials were consolidated via spark plasma sintering and high-pressure high-temperature (HPHT) sintering methods. Fully dense ZrC-TiC compacts were produced by HTHP SPS technique at 1600-1700°C and were characterized by 370 GPa and 23.7 GPa values of Young’s modulus and Vickers microhardness, respectively. By the addition of 2 wt.% silicon nitride, the compacts of a full density were obtained at 1600°C; however, the further addition of Si3N4 resulted in a decrease in both density and hardness. Oxidation behavior in air of the ZrC-TiC and ZrC-TiC-Si3N4 compacts was explored by high temperature XRD method showing intensive oxidation at ~1000°C. Microstructural analysis certified that the addition of certain amount of Si3N4 increases the phase distribution homogeneity and contributes to the microstructure refinement.