Identification of deformation and failure mechanisms of the hierarchical structure of hard biological materials through different length scale, with emphasis on biomineralized marine organisms such as mollusk shells, radular teeth and crustaceans exoskeletons. Biomimetics applied to the intelligent design of materials: Design and modeling of synthetic nano/micro-composites mimicking hard biological materials using bioinspired damage mitigation strategies. Development of multiscale models for bio-inspired materials. Strong collaboration with material scientists, chemists and biologists.
Nacre, the iridescent material found in Abalone shells, exhibits remarkable strength and toughness despite its composition of over 95% brittle ceramic. Its hierarchical structure over multiple length scales gives rise to its increase in toughness despite its material composition. In this work we develop a computational model of composites incorporating key morphological features of nacre’s microstructure. By conducting a parametric analysis we are able to determine an optimal geometry that increases energy dissipation over 70 times. We discuss the contribution of varying ceramic strengths and size effect to see how this affects the overall performance of the composite. We then compare our simulations to experiments performed on a material possessing the same microstructure investigated computationally. For both simulations and experiments we show that our optimal geometry corresponds to that of natural nacre indicating the importance of specifically incorporating nacre’s key morphological and constituent features. This combination of simulations and experiments gives great insight to the delicate interplay between material parameters and microstructure showing that if we optimally combine all aspects, we can develop novel synthetic materials with superior performance.
Researchers should cite this work as follows: