Data-driven analysis in co-designed experimental, theoretical, and numerical investigations of effective material properties in granular materials have been performed. Specifically, the Young's modulus for cold compacted powder materials has been targeted. Co-designed experimental, theoretical, and numerical investigations aiming at estimating the value of the Young's modulus for cold compacted powder materials have been undertaken. The concept of image-based modeling has been used to reconstruct the morphology of the powder structure with high fidelity. Analyses on aluminum powder pellets provide significant understanding of the microstructural mechanisms that preside the increase of the elastic properties with compaction. The role of the stress percolation path and its evolution during material densification has been highlighted and a scaling law for the surface contact area between powder particles has been proposed. At the same time high-performance computing analyses of Reverse Taylor impact tests on solid pellets, at strains in the order of 7000s-1 modeled with large strain crystal plasticity were successfully dealt with. Finally, a new visco-plastic model for granular materials is under development. This model accounts for the rate dependence, elasto-plastic coupling, pressure sensitivity, and transition to full solid state. The model has been implemented, verified, and validated against experimental analyses available in the literature for copper powder compounds.
Salvadori A., Lee S., Gillman A., Matous K., Shuck C., Mukasyan A., Beason M., Gunduz I.E., Son S.F., Numerical and experimental analysis of the Young's modulus of cold compacted powder materials, Mechanics of Materials, 112 (2017) 56-70
Krairi A., Matous K, Salvadori A., A poro-viscoplastic constitutive model for granular materials at finite strains, submitted to the International Journal of Solids and Structures, 2017