Design of optimised multi-scale structures for multifunctional composites

The multi-scale structures are commonly found in nature, such as plants and bones. Such multi-scale structures can be divided into macro-scale, micro-scale and further sub-scale structures. In this study, we aim to design optimised two-scale structures for multifunctional composites, specifically by enhancing the structural stiffness and the ionic conductivity simultaneously. To tackle this problem, a novel strategy for achieving optimised multiscale structures is presented. A database of optimised micro-scale structures and simple placement criterion for the micro-scale structure were applied. We demonstrate the efficiency of our strategy by designing, optimising and evaluating two-scale structures composed of macro-and micro-scales. The advantage of our strategy for optimised multi-scale structures is presented and discussed by comparing the structural stiffness and the ionic conductivity of several two-scale structures composed of different microstructures such as the solid-void, uniform and varied microstructures