Bioinspired Feather Shaft Sinusoidal Chiral Structure for Enhanced Energy Absorption Under Quasistatic and Impact Loading

Modern engineering applications impose stringent demands on structural energy absorption (EA) efficiency and stability. Nevertheless, achieving integrated structural designs that synergize high load‐bearing capacity, impact resistance, and lightweight attributes remains a considerable challenge. To address this issue, a bioinspired sinusoidal chiral (BSC) structure, derived from the cortical layer of a feather rachis cross‐section, is proposed. The unique configuration of BSC promotes enhanced intercell interactions, which collectively induce global shear deformation under compression. This coordinated deformation mode strengthens the structural negative Poisson's ratio effect, contributing to more stable and efficient energy dissipation. Finite element simulations and quasistatic compression experiments are conducted to evaluate its mechanical performance and EA behavior. Compared with traditional chiral (TC) structures, the BSC exhibits remarkable enhancements, achieving increases of 115.10% in EA, 96.74% in plateau stress, and 10.94% in densification strain under equivalent filling ratios. Additionally, the effects of key geometric parameters—the unit angle, sinusoidal amplitude, and wall thickness—on the EA characteristics were systematically examined. The results demonstrate that increases in both amplitude and wall thickness lead to significant enhancements in load‐bearing capacity. Furthermore, the dynamic mechanical response of the BSC structure was evaluated under various impact loading conditions through finite element simulations. This study provides valuable insights for the design of metamaterial structures with superior mechanical and energy‐absorbing properties, demonstrating promising potential for engineering applications.