Irregular Networks Reinforced Composites—From Bioinspired Design to Mechanical Performance

Composites with high strength and high fracture resistance are desirable for structural and protective applications. Most composites, however, suffer from poor damage tolerance and are prone to unpredictable fractures. In my talk, I will report an approach to design architected polymer composites reinforced by a continuous irregular network generated through a virtual growth algorithm. [1] The algorithm stochastically assembles a selection of simple tiles relying on predefined adjacency rules that control independently the topology and the local geometry of the microstructure, achieving mechanical reinforcement across multiple length scales. [1] Using quasi-static and dynamic mechanical testing, I will highlight how the reinforcing architecture of the composites influences the strength, the stiffness, and the energy dissipated during fracture. Using 2D-Digital Image Correlation, I will showcase the local mechanisms that influence the initiation and the propagation of fractures in the composites. With these findings, I will finally demonstrate how the temporal and spatial propagation of fractures in architected composites can be designed and controlled <i>a priori</i>, combining different reinforcing networks into a spatially determined meso-scale assemblies. [1]<br/><br/>[1] T. Magrini, C. Fox, A. Wihardja, A. Kolli, C. Daraio. "Control of Mechanical and Fracture Properties in Two-phase Materials Reinforced by Continuous, Irregular Networks." <i>Advanced Materials</i>, 2023