The intrinsic brittleness and strong chemical bonds in ceramics are persistently challenging, which hinders dislocation nucleation and atomic slip to accommodate strains. This characteristic impedes plastic deformation for ceramic matrix composites in withstanding dynamic mechanical loading and intense scouring in severe thermal environments. To address these challenges, a nano-dispersion strengthening strategy is involved for the C/C-ZrC-SiC composites through a meltable organic-inorganic hybrid infiltration strategy. The introduction of organic-derived ZrC nanoparticles increased dislocation nucleation via pinning effects and enhanced atomic slip by inducing phase transformation, thereby improving the plasticity of both matrix and the oxide layer. The optimal composite, with a volume ratio of organic zirconium acetylacetonate to inorganic Si-Zr melt (2:1), P2S1, exhibited the best comprehensive performance, achieving a flexural strength of 207.5 ± 2.3 MPa and a linear ablation rate of 0.15 μm·s-1 under plasma ablation. This enhancement is achieved through tailored ZrC nanoparticle-induced 3C→6H-SiC phase transformation in the matrix, and further generates ZrO2 nanoparticle-induced martensitic transformation in the dense oxide film. This study presents an effective way to enhance plasticity in ceramics and develop advanced nano-dispersion-strengthened ceramic matrix composites with excellent mechanical and ablation resistance in extreme thermal environments.
Zhang et al. (2026) studied this question.