Failure of disordered solids

Disordered solids are everywhere in our daily life, from ordinary windowpanes to granular materials. They play such a significant role that the United Nations declared 2022 to be the International Year of the Glass (IYOG2022).  Understanding how disordered solids break is also a major focus in our group. The complexity here stems from the multi-scale (in both space and time) interplay between microstructural disorder and the overall elastic (or elastodynamic) stress redistribution following micro-fracturing events, eventually mediated by environmentally dependent thermally activated processes.

Over the past five years, work performed at SPHYNX has focused on both slow and fast fracture regimes:

• First, we sought to understand better the role played by the oxide glass structure, and other properties[1], on the stress corrosion cracking properties of homogeneous and phase-separated oxide glasses[2].
• Second, we examined how the drying rate selects mesostructured disorder, and subsequently mechanical and failure properties of solid layers obtained from the drying of nanocolloidal suspensions[3].  Third, we studied how stress waves emerge from the interaction between a fast growing crack and a defect[4].
• Finally, a new endeavor was undertaken to create novel ultralight metamaterials resistant to both fracture and deformation.  These new materials have the specificity to exhibit isotropic disordered architectures[5]  contrary to many standard mechanical metamaterials, and AI techniques is currently used to optimize their architectures.

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[1] M. Mama Toulou et al., Systematic approach to thermophysical and mechanical properties of SiO2–B2O3–Na2O glasses using molecular dynamics simulations, Journal of Non-Crystalline Solids 603, 122099 (2023).
[2] W. Feng  et al., Stress Corrosion Cracking in Amorphous Phase Separated Oxide Glasses: A Holistic Review of Their Structures, Physical, Mechanical and Fracture Properties 2, 412-446 (2021)
[3] A. Lesaine et al., Role of particle aggregation in the structure of dried colloidal silica layers, Soft Matter 7, 1589-1600 (2021)
[4] A. Dubois & D. Bonamy, Dynamic crack growth along heterogeneous planar interfaces: Interaction with unidimensional strips, Physical Review E 103, 013004 (2021) 
[5] A. Montiel et al. Procédé de fabrication d’un micro-treillis formé de micro-poutres reliées entre elles par des nœuds, patent deposited on 13 March 2022

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