In situ X-ray tomography measurements of deformation in cellular solids

The use of microtomography to study the structure and especially the deformation modes of cellular solids is reviewed in this article. First, the technique is described in detail. Examples illustrating the power of the coupling of in situ deformation with three-dimensional (3D) imaging, drawn from the recent literature and the authors' own work, are then given. The most detailed example is the study of the deformation modes of several samples made of different aluminum foams. Four kinds of closed-cell foams were investigated, corresponding to different routes available today for their manufacture. The initial macrostructure was quantified using the 3D images combined with 3D granulometry, allowing retrieval of pertinent information about the cells size and the walk and strut thicknesses. The global behavior exhibited by the foams during the in situ compression experiments was shown to vary from one band of material to another. Some of these variations can be explained by differences in the known microstructure and the measured macrostructure of the samples.