Spark plasma sintering and characterization of ZrC-TiB2 composites

ZrC-based composites were consolidated from ZrC and TiB2 powders by the Spark Plasma Sintering (SPS) technique at 1685 °C and 1700 °C for 300 s under 40-50-60 MPa. Densification, crystalline phases, microstructure, mechanical properties and oxidation behavior of the composites were investigated. The sintered bodies were composed of a (Zr,Ti)C solid solution and a ZrB phase. The densification behaviors of the composites were improved by increasing the TiB2 content and applied pressure. The highest value of hardness, 21.64 GPa, was attained with the addition of 30 vol% TiB2. Oxidation tests were performed at 900 °C for 2 h and the formation of ZrO2, TiO2 and B2O3 phases were identified by using XRD.