Theoretical study on the effects of Si doping on the interface adhesion and failure behaviors of SiC/BN interface

Abstract Hexagonal boron nitride ( h ‐BN), owing to its extraordinary capability to deflect cracks, a property rooted in its lamellar architecture, emerges as an exemplary interphase material. With the introduction of silicon dopant, its high‐temperature resistance at temperatures exceeding 1000°C is significantly bolstered. To elucidate the impact of silicon doping on crack deflection behavior, first‐principles calculations are conducted to comparatively analyze interface bonding characteristics and failure behaviors of SiC/BN and SiC/(BN) 4 Si interfaces. The findings indicate that silicon doping fortifies interface adhesion and ideal debonding strength while diminishing the failure strength across the interface, thereby reducing the propensity for crack deflection. Nonetheless, there remains considerable potential for enhancing strengthening and toughening effects of silicon‐doped h ‐BN interphase by meticulously adjusting the interface strength. This study provides invaluable insights into the design of silicon‐doped h ‐BN interphases, underscoring the critical importance of balancing a robust interface with a relatively weaker interphase.