UC Riverside

Biologically mineralized composites offer inspiration for the design of next generation structural materials due to their environmentally friendly synthesis, low density, and combination of high stiffness and toughness, currently unmatched by engineering technologies. Such properties are the result of hierarchical structuring and well-defined compositional and mechanical gradients afforded by the organism’s ability to control the self-assembly and nucleation and growth of organic and inorganic materials, respectively. Here, we investigate structure-mechanical property relationships of two incredibly damage-tolerant and impact-resistant bio-composite materials: the mantis shrimp dactyl club and telson, which resist catastrophic failure from repeated high-energy impacts and cavitation from one of the fastest striking events observed in nature. We identify numerous multi-length scale architectural designs that play key roles in imparting stiffness, compliance as well as delocalizing stress and enhancing toughness. These design cues are then translated and implemented into biomimetic composite materials that are fabricated using traditional fiber-reinforced composites processing as well as advanced direct ink write additive manufacturing. The ability for these biomimetic composites to demonstrate enhanced damage-tolerance over traditional designs is then assess through mechanical testing. Such findings may prove useful for the on-going design and fabrication of lightweight structural materials possessing improved damage-tolerance.