Oxidation studies on TaC based ultra-high temperature ceramic composites under plasma arc jet exposure

An ultra-high temperature ceramic, TaC, is reinforced with SiC and carbon nanotubes (CNTs) to provide protection under extreme thermal and chemical environments. High temperature performance of spark plasma sintered TaC-based composites was evaluated through plasma arc-jet exposure under heat-flux of 2.5 MW/m(2) for 30 s. The composite shows a significant improvement in the oxidation resistance compared to that of TaC. Complimentarily, thermogravimetric analyses (up to 1500 degrees C) elicits shift in the onset temperature of oxide formation from 735 degrees C in TaC to 901 degrees C (with synergistic addition of both SiC and CNT) insinuating the enhanced thermal stability of TaC-SiC-CNT composites. (C) 2016 Elsevier Ltd. All rights reserved.