Enhancing puncture resistance in composite protective structures via bio-inspired carp fish scale-tissue architectures

This paper reports the superior low-velocity impact performance of a composite scale-tissue-inspired protective system over a conventional bi-layer structure. The bio-inspired structure was modelled after the geometry and architecture of carp fish scales, while the bi-layer structure was designed with the same scale volume fraction atop a tissue layer. Both designs were subjected to low-velocity puncture tests with three different impactor geometries and three energy levels, 10 J resulting in rebound, 15 J for a transition between rebound and perforation, and 20 J resulting in perforation, to evaluate the full range of specimen responses under varying impact energies. The puncture test results confirmed the superior protective performance of the bio-inspired scale-tissue structure, as it withstood higher impact loads without perforation. In fully perforated cases, the bio-inspired design absorbed more energy than the bi-layer design. Additionally, the bio-inspired configuration exhibited a more consistent impact response, with energy absorption standard deviation lower than 4%. Computed tomography imaging of the post-impacted samples showed smaller damage areas in the bio-inspired samples. These results highlighted the unique design features of composite scale-tissue-inspired protective structures and their potential to enhance the performance of future impact-resistant designs.