Study on Multidirectional Hybrid Effect and Failure Mechanisms of Carbon/Basalt Fiber Bionic Double‐Helicoidal Composite Laminates

ABSTRACT Fiber hybrid can obtain adjustable and more balanced mechanical properties (stiffness, strength, elongation, etc.), but due to the complexity of hybrid effects, there is a lack of research on multidirectional fiber hybrid design. In this study, carbon/basalt fiber double‐helicoidal (DH) composite specimens were designed, drawing inspiration from the collagen fiber structure of coelacanth scales and the soft‐hard hybrid system of sea sponge. The effects of helicoidal angles and hybrid effects on the tensile properties of CF/BF hybrid fiber‐reinforced polymer (HFRP) composite laminates were studied by tensile test and numerical simulation. The results indicate that the helicoidal angle significantly influences the tensile properties of laminates, and the tensile modulus of sine rotation angle (SRA) laminate is higher than that of linear rotation angle (LRA) laminate and exponential rotation angle (ERA) laminate. The laminates with a small rotation angle have excellent ductility and damage tolerance. Through microscopic characterization, it is found that delamination and interface failure are the main failure modes of DH‐HFRP. Using a validated numerical model, the mechanical behavior of DH‐HFRP laminates is qualitatively investigated. It is discovered that the direction factor and dispersion have coupling impacts on its mechanical behaviors. This work aims to serve as a reference for designing biomimetic hybrid fiber composites.