Enhanced mechanical properties and mechanisms of ceramic layer toughened by a surface‐modified SiC whisker

Abstract To enhance the service longevity and operational stability of thermal barrier coatings (TBCs), surface‐modified silicon carbide whiskers (SiC _w ) have been strategically integrated into yttria‐stabilized zirconia (YSZ) matrices. This study systematically evaluates the influence of SiC _w surface modification on the mechanical integrity of composite coatings. Quantitative analysis reveals that the surface‐functionalized SiC _w effectively reduces coating porosity while concurrently enhancing mechanical performance. Notably, the YSZ‐W _L composite coating exhibited superior fracture toughness, demonstrating a 25–35% improvement relative to the baseline YSZ system. Post‐sintering evaluation further substantiated that the YSZ‐W _L ceramic layer retains exceptional tensile resistance and flexural load‐bearing capacity. Accelerated erosion testing revealed an 18.5% reduction in mass loss rate for YSZ‐W _L (1.072 mg/g) compared to conventional YSZ (1.316 mg/g). The toughening mechanisms governing the modified SiC _w ‐reinforced system are attributed to three synergistic effects: (I) Optimized interfacial bonding, (II) Crack deflection, and (III) Enhanced whisker pull‐out resistance.