Ablation-Immune Thermal Armor Via Microstructural-Compatibility Design for Extreme Thermal Conditions.

To overcome the brittleness and microstructural degradation of ultrahigh temperature ceramics (UHTCs) in hypersonic thermal protection systems, this work develops a C/C-ZrC-SiC/ZrC-SiC composite via a microstructural-compatibility design that integrates reactive melt infiltration with supersonic atmospheric plasma spraying. Critically, this work strategically incorporated SiC as a dispersed phase in the ZrC coating to actively regulate the deposition thermodynamics and oxidation kinetics, which suppresses the formation of continuous, lamellar ZrO2 interlayers and mitigates residual stress. Consequently, the designed composite demonstrates exceptional ablation resistance, withstanding oxyacetylene ablation (2200°C) for 3080 s and Ar-H2 plasma ablation (2600°C) for 1500 s, while achieving an ultralow linear ablation rate on the order of 10-5 mm s-1. This work validates a microstructural-compatibility-led design principle, providing a foundational blueprint for developing thermal protection systems.