Structure-Property Relationships, and Biomimetic Designs from the Compression-Resistant Cuticle of the Ironclad Beetle

Biological composites provide valuable design guidelines to produce the next generation of engineering materials. Incorporating readily available resources in environmentally friendly method, these biological organisms produce lightweight, strong, and tough materials with superior mechanical properties to engineering counterparts. The key to this success results from their hierarchical organization as well as structural and compositional gradients imparted by an ordered self-assembly of organic material. In this work we study the structure-mechanical property relationship and multifunctional nature of a compression resistant beetle elytra able to withstand crushing and piercing attacks from predators while thriving in an arid desert environment. We uncover the macro and microstructural architectural features responsible for transferring stress and imparting localized stiffness and compliance to toughen the bulk biological composite. These insights are then subsequently applied to the fabrication of bioinspired fiber reinforced composites using conventional engineering materials and additive manufacturing. Validating their performance, mechanical testing was used to highlight the enhanced performance of these biological materials compared to industry standard designs. This work may further provide insights into the fabrication of lightweight, strong, and tough structural materials for use in engineering applications.