Optimization on the Flexural Performance of Bio‐Inspired Helicoidal Hybrid Composite Laminates

ABSTRACT Hybrid composites have been widely known for their significant advantages in improving carrying characteristics and balancing cost and performance, and bio‐inspired designs (e.g., helical structures) can also enhance mechanical properties. However, the combined effects of hybrid and bio‐inspired helical ply on mechanical properties remain insufficiently studied. Herein, the hybrid structures and bio‐inspired helical ply angles were employed as design variables. The effects of varying hybrid structures and bio‐inspired designs on flexural properties were systematically investigated via three‐point bending tests, combined with digital image correlation (DIC) and scanning electron microscopy (SEM) to characterize strain distribution and failure modes. The results demonstrate that a specific hybrid layup increased flexural strength and energy absorption by 15.9% and 194% compared with the pure carbon fiber laminate. The double‐helical structure significantly enhanced energy absorption maintaining high modulus/strength in contrast with the benchmark hybrid structure. Based on a progressive damage finite element model, which accurately simulated the flexural responses of laminates, Hybrid structure and helical ply angle were synchronously optimized using the Taguchi‐gray relational analysis method. The optimized architecture exhibited a 33.5% improvement in flexural performance and a 20.1% reduction in material cost compared with the benchmark design.