Review: Recent advances in SiC ceramics for ballistic armor—sintering optimization, toughening strategies and bioinspired structural design

Silicon carbide (SiC) ceramics are critical for advanced ballistic protection owing to their exceptional hardness (> 25 GPa), low density (~ 3.21 g/cm³), and high chemical stability. This review provides a comprehensive analysis of recent advances in SiC armor systems, structured around three interdependent themes: (1) sintering optimization (spanning pressureless sintering, hot pressing, reaction sintering, spark plasma sintering, and hot isostatic pressing) to achieve precise densification and grain boundary control; (2) multimechanism toughening strategies—including self-toughening, fiber/whisker reinforcement, particulate toughening, and phase-transformation toughening—to mitigate intrinsic brittleness and suppress catastrophic failure under impact; and (3) bioinspired and functionally graded architectures engineered for staged stress wave attenuation and enhanced multihit resistance. We identify microstructural homogeneity, grain boundary engineering, and the use of high-purity, low-oxygen-content precursor powders as the dominant factors governing ballistic efficiency. By elucidating the process–structure–property relationships in SiC armor, this work establishes a strategic roadmap for next-generation lightweight protective ceramics. Future directions are proposed in the areas of high-purity powder synthesis, multiscale toughening synergy, and data-driven structural design to address evolving demands in both military and civilian protection.