Mechanical properties of unidirectional bio-inspired composites with two non-self-similar hierarchical structures

Abstract

There are many examples of hierarchical structures in nature such as teeth, antler, bone, and nacre which point to the possibility of creating new bio-inspired structures with superior mechanical properties. In this paper, the analysis of mechanical properties of uni-directional non-self-similar bio-inspired composites with two non-self-similar hierarchical structures is done using an existing popular model called Tension–Shear chain (TSC) model. We found that the so formed two hierarchical composites hold a good match with the Finite Element Analysis results in the case of Young’s modulus. These two hierarchical composites are seen to maintain a reasonable strength with very high toughness compared to that of the single hierarchical composites and may be used for applications where more toughness is required rather than strength. Moreover, the optimum aspect ratios at the first and second levels of hierarchies are evaluated in this study and a comparison of maximum toughness that can be achieved in a particular configuration is also made. These studies could be useful in the design and development of tough bio-inspired composites.