Effect of scale morphology on the mechanical response of bio-inspired fish-scale-based protective structures
Hari Bahadur Dura, Paul J. Hazell, Hongxu Wang, J. P. Escobedo
Abstract
A numerical and experimental approach has been used to study the bending stiffness properties of a biomimetic protective beam, inspired by curved elasmoid fish scales. Thermoplastic Polyurethane was used for the tissue material and Acrylonitrile Butadiene Styrene for the scales. Quasi-static and dynamic loading conditions were employed to study the effect of strain rate on the structures. Finite element analysis and digital image correlation were used to investigate the stiffening mechanism in bioinspired samples. The flexural stiffness of the bio-inspired design could be improved by 9 % compared to the baseline design (i.e., straight plate scales). The scales with smaller radii showed greater structural resilience. The experimental results at a 10-4 /s strain rate showed that the specific energy absorption by the scale model with a radius of 100 mm was ∼6% higher than that of the baseline model. The fish scale morphology can be mimicked to design better protective structures.