Penetration resistance characteristics of bioinspired helical laminated composite structures against projectile impact

Achieving both high strength and toughness in lightweight structural materials under extreme loading conditions remains a core challenge in composite structural design. Inspired by the helicoidal laminated architecture of the mantis shrimp's dactyl club, bioinspired helicoidal carbon fiber/epoxy composite laminates with different interlaminar helix angles were designed and fabricated in this study. The penetration resistance characteristics, dynamic response, and energy absorption performance of these laminates under projectile impact were investigated through a combined experimental and numerical approach. The results indicated that the interlaminar helix angle significantly affects the impact resistance of the structure, the 15° configuration achieved a 45% higher energy absorption than the cross-ply configuration, demonstrating superior comprehensive performance. Further analysis revealed that variation in helix angle significantly alters the internal stress distribution, intralaminar axial and transverse stresses induce fiber fracture and matrix cracking, while interlaminar shear stresses drive delamination along helical shear paths, giving rise to a unique multi-mode progressive damage mechanism. These findings elucidate the mechanisms underlying strength and toughness enhancement in helicoidal architectures under projectile impact, highlighting the critical role in enhancing impact resistance and energy dissipation. The results provide valuable guidance for the structural design and performance optimization of high-performance composite materials with promising application potential.