A biomimetic composite structure is investigated to explore the effect of angled ductile layers. The composite structure is idealized as layers of ductile material mixed with layers of hard brittle material in a rectangular bar. The layers zig zag across length of the structure with the aim to promote crack diversion. The novelty of this study is the use of such angular layers based on biomimetic inspiration from a horse hoof keratin structure. Specimens were manufactured using 3D printing technique to study the effect of different layer angles, layer thickness and crack location by single-edge notch bending test. Results showed that traditional flat thick layers provide a strong material, but zig-zagged layers are better at dispersing stress to maintain structural integrity after an impact or fatigue crack. This work provides a creative and innovative approach to design core layers in composite sandwich structures with enhanced damage tolerance.
Rice, C., & Tan, K. T. (2019). Horse hoof inspired biomimetic structure for improved damage tolerance and crack diversion. Composite Structures, 220, 362–370. https://doi.org/10.1016/j.compstruct.2019.04.009