Mechanical Behavior of Bio-Inspired Composites with Sutural Tessellation

Abstract

In nature, architectured composites with sutural tessellations are found in the armor systems of many fauna and flora species across all length scales. These composites are typically composed of relatively stiff building blocks articulated via compliant wavy suture interfaces, showing a remarkable jigsaw-puzzle-like sutural tessellation. Inspired by these interesting natural composites, bio-inspired designs of architectured composite plates with diamond-shaped building blocks and sinusoidal suture tessellations were developed. Finite element simulations were performed to study the influences of the waviness and the stiffness ratio of the suture tessellation on the overall stress-strain behavior of the designs. Suture tessellation was shown to be essential in determining the mechanical properties and behavior of the composite plates. The waviness and the stiffness ratio of the suture tessellation were found to be the most important geometric and material parameters to govern the mechanical behavior of the composite plates. The effective stiffness and Poisson’s ratio of the architectured biomimetic composite plate can be tuned in a very large range by tailoring the geometry and material combination of the suture tessellation. Generally, for a certain stiffness ratio and volume fraction, when the waviness of suture tessellation increases, the effective stiffness increases. Interestingly, for cases with wavy suture tessellation and large stiffness ratio, negative Poisson’s ratio can be achieved. These results provide a guideline for designing new composite materials for protection and energy dissipation.