This research explores the hypothesis that localized planar compaction band formation in high porosity materials is a common, perhaps inevitable, deformation mode, analogous to the buckling of long, slender columns. Surface strain mapping examines the transition in deformation behavior of uniaxially compressed aluminum foams, from diffuse compaction to band formation. Scanning electron microscopy and X-ray computed tomography are used to characterize the microstructural deformation processes. Compaction bands are modeled as a bifurcation from uniform deformation, due to a constitutive instability. Therefore, theoretical work models the pre-localization inelastic response, using continuum and micromechanics approaches. Combining results from this project with the PI's sandstone research will enable development of a model to predict compaction localization in various natural and manufactured porous solids, with diverse microstructures and a broad range of applications. Strain localization is a fundamental solid mechanics problem, and porous solids are an economically and socially important class of materials.
