Nacre Inspired Silicon Carbide Whiskers Embedded Bilayer Hydrothermal Carbon Interphase for Strengthening Carbon Fiber-Reinforced Zirconium Boride - Silicon Carbide Composites
Abstract
Inspired by the mineral bridge mechanism in nacreous architectures, this study proposes a novel interface design aimed at enhancing the comprehensive mechanical properties of carbon fiber-reinforced ZrB2-SiC composites. Silicon carbide whiskers (SiCw) were incorporated as structural bridges between bilayer hydrothermal carbon coatings (HTCC), leading to the successful construction of a hierarchical HTCC-SiCw-HTCC (HSwH) interphase via stepwise hydrothermal synthesis. The SiCw bridges not only strengthened the interlayer bonding but also maintained controlled interfacial slippage, achieving a synergistic balance between efficient load transfer and energy dissipation. Mechanical characterization demonstrated that the HSwH-modified composites exhibited significantly enhanced flexural strength (318 ± 37 MPa) while retaining high fracture toughness (7.36 ± 0.91 MPa·m1/2), surpassing the performance of conventional bilayer HTCC systems. Additionally, thermal shock resistance was markedly improved, with critical failure temperatures reaching 908 ℃ for the optimized composite. This work presents a biomimetic strategy for designing high-performance interfaces in carbon fiber toughened ceramic matrix composites.