Evaluation of the influence of pore structural parameters on the mechanical properties of foam glasses via in-situ micro-CT mechanical testing

Open-cell foam glasses are ideal model systems for investigating the mechanical behavior of macroporous materials. However, a detailed mechanistic understanding linking specific pore-scale features to mechanical failure remains a key challenge. In this study, we investigated the relationships between pore structure and mechanical properties, specifically Young's modulus and compressive strength, in three open-cell monolithic foam glass samples, which serve as model systems for macroporous silica monoliths. With the results of micro-computed tomography (micro-CT) combined with ex-situ and in-situ uniaxial compression experiments and Digital Volume Correlation (DVC) analysis we demonstrate an inverse relationship between mechanical strength and factors including wall thickness and porosity, with compressive strength following a power-law correlation with the proportion of large pores. Multi-peak stress-strain behavior indicates micro-cracking within the porous lattice, while micro-CT imaging reveals damage localization at the specimen boundaries and strain-induced changes in porosity, mean pore diameter, and sphericity. DVC analysis further validated these findings. This work provides mechanistic insights essential for the rational design and optimization of macroporous materials.