Bioinspired Multifunctional Composites—Processing, Mechanics and Functionalities

Progress in lightweight composites design and manufacturing is paramount for the growth of an energy-efficient aircraft and transportation sector. However, designing composites with high strength and high fracture toughness remains an open challenge due to the trade-off between these properties in most synthetic materials. Replicating the hierarchical internal architecture of mollusk shells, I developed a novel class of strong and tough composites, reinforced across multiple length scales, from the nm- to the mm- scale. This new material platform allows to unveil the mechanisms responsible for high crack growth resistance in hierarchical architectures, and to address the timescale at which each mechanism activates during damage. Using <i>in situ</i> controlled mechanics and fracture testing, in combination with optical and electron microscopy, I visualize and study the mechanisms of fracture propagation. Furthermore, introducing stress-sensing functionalities in the organic phase of the composites, I use simple optical readouts, like color changes, to quantify the role of the matrix during composite fracture, and to preemptively detect the fracture trajectory during loading. In my presentation, I will highlight how multifunctional bioinspired composites can combine high mechanical performance and novel functionalities, and how these provide new insights into the interplay of multiscale toughening mechanisms, offering guidelines for the design and manufacturing of superior hierarchical composites.<br/><br/>T Magrini, A Senol, R Style, F Bouville, AR Studart, <i>Journal of the Mechanics and Physics of Solids</i> (2022) 159, 104750<br/>T Magrini, D Kiebala, D Grimm, A Nelson, S Schrettl, F Bouville, C Weder, AR Studart, <i>ACS Applied Materials & Interfaces </i>(2021) 13 (23), 27481-27490