Breaking the Temperature Barrier With a SiC‐Enhanced High‐Entropy Ceramic With Unprecedented Stability up to 3000°C

ABSTRACT Advancing ultra‐high‐temperature materials requires superior oxidation resistance for hypersonic flight, atmospheric reentry, and propulsion systems, yet their service temperatures remain limited to below 3000°C. Herein, we put forward a component modulation strategy for the fabrication of SiC‐enhanced high‐entropy ceramics, with SHC‐3 demonstrating the lowest mass ablation rate (1.58 mg·s −1 ) and linear ablation rate (0.67 µm·s −1 ) while exhibiting outstanding ablation resistance under various extreme high‐temperature conditions. The incorporation of SiC particles significantly enhances the densification of SHC‐3, increasing its hardness to 33.1 GPa, while the observed crack deflection induced by the SiC particles is considered a key mechanism for strengthening and toughening the material. The superior ablation resistance of SHC‐3 is attributed to the synergistic effects of SiC‐assisted densification and crack deflection, the formation of a SiO 2 ‐rich protective phase under ultra‐high‐temperature ablation conditions, and the lattice‐distortion‐related diffusion retardation of the high‐entropy carbide matrix, which collectively suppress oxygen penetration and slow material degradation. This study demonstrates significant progress in the application of high‐entropy ceramics at extreme temperatures up to 3000°C and lays the foundation for designing advanced materials capable of operating at even higher temperatures.