The oxidation resistance and plasma ablation performance at 3000 K of HfC-TiC ultra-high temperature ceramics

Abstract

Ultra-high-temperature ceramics (UHTCs), owing to their exceptional performance under extreme heat and harsh conditions, have become the preferred choice for critical thermal protection materials in high-speed aerospace vehicles. Here, the HfC-TiC ceramics were fabricated through pressureless sintering, and its oxidation behaivor was investigated using non-isothermal method. The oxidation activation energy of HfC-TiC sample reaches 385.39 kJ/mol. Then the ablation behavior of HfC-TiC ceramics was tested under plasma ablation conditions (3000 K, 5.0 MW/m²). The mass ablation rate and linear ablation rate of HfC-TiC can reach −1.11 × 10⁻³ g·s⁻¹ and −1.40 × 10⁻³ mm·s⁻¹ after being ablated for 300 seconds, respectively. The oxide layers in the center consisted of a porous oxide upper layer, a dense Ti-enriched intermediate layer, and an oxide inner layer. This complex multi-layered oxidative configuration synergistically protected the underlying carbide matrix, significantly enhancing the ablation resistance of HfC-TiC ceramics.