Simulating effects of microstructure on the mechanical response of flexible foams

Abstract

Flexible foams with stochastic microstructures are widely employed in impact mitigation, yet the connection between microstructure and mechanical performance remains incompletely understood. This study combines computational foam generation with high-throughput finite element simulations to quantify the effects of microstructural features on compressive response. Synthetic microstructures created using a regularized Voronoi tessellation and a bubble growth algorithm closely replicate experimentally observed distributions of cell area, interior angle, and wall count. In contrast, conventional random Voronoi foams exhibit nonphysical features. Simulations reveal that increasing microstructural regularity enhances stiffness and strength under uniaxial compression. Geometrical and mechanical representative volume elements (RVEs) are identified, requiring 10 × 10 and 30 × 30 cell arrays, respectively. Energy dissipation analysis shows that extreme or irregular cells reduce mechanical efficiency. These findings underscore the critical role of microstructural control in foam design and suggest that tuning size distribution and regularity can enable application-specific optimization of mechanical properties.