Universal composition–structure–property maps for natural and biomimetic platelet–matrix composites and stacked heterostructures

Many natural and biomimetic platelet–matrix composites—such as nacre, silk, and clay-polymer—exhibit a remarkable balance of strength, toughness and/or stiffness, which call for a universal measure to quantify this outstanding feature given the structure and material characteristics of the constituents. Analogously, there is an urgent need to quantify the mechanics of emerging electronic and photonic systems such as stacked heterostructures. Here we report the development of a unified framework to construct universal composition–structure–property diagrams that decode the interplay between various geometries and inherent material features in both platelet–matrix composites and stacked heterostructures. We study the effects of elastic and elastic-perfectly plastic matrices, overlap offset ratio and the competing mechanisms of platelet versus matrix failures. Validated by several 3D-printed specimens and a wide range of natural and synthetic materials across scales, the proposed universally valid diagrams have important implications for science-based engineering of numerous platelet–matrix composites and stacked heterostructures. Many layered composites exhibit a remarkable balance of strength, toughness and stiffness. Here, the authors construct a model to explain the synergy of key mechanical properties of layered composites by considering the elastic/plastic properties of the matrix and use 3D-printed samples to validate their predictions.