3-D image-based mechanical simulation of aluminium foams: Effects of internal microstructure

SR (Synchrotron radiation) X-ray microtomography has been utilized for the 3D characterization of microstructures in an aluminum foam. Volume tomographic data sets are converted into stereolithography tessellation language (STL) models to create 3-D finite-element simulation models. Both quasi-static and dynamic deformation and damage behaviours are investigated numerically, especially focussing on the effects of relatively small micro-pores inside cell wall materials. It has been fairly obvious that the existence of micro-pores and their spatial distribution pattern in cell materials would be a key issue to control the deformation and fracture behaviours. It has been also clarified that the stress wave propagation during the dynamic loading is prone to relatively uniform local stress elevation compared to the case of the static compression, thereby more extensive damage is predicted in the case of the dynamic loading due to the increase in volume sampled by an external loading. These results are in qualitative agreement with experimental observations. Overall, the approach taken in this study has provided highly effective ways to characterize microstructure/properties relationships in such highly heterogeneous materials.