Determination of Mechanical Properties of Materials with Complex Inner Structure Using Microstructural Models

Among materials with complex inner structure are ranked cellular materials, typically represented by trabecular bone and polymer or metal foams. Geometrical similarity of their internal structure allows determination of material characteristics of trabecular bone using models originally developed for analysis of polymer and metal foams. In this paper, mechanical behavior of cellular materials is studied by modeling their internal structure and analysis using Finite Element Method (FEM). Alporas aluminium foam was selected as a reference material and the material characteristics were derived from tensile loading using numerical FEM analysis. Internal structure of the foam was modeled by two different methods using voxel model created on the basis of a series of CT scans and by discretization using Gibson-Ashby's cellular model. Mechanical behavior analysis was performed in both elastic and plastic fields. The beam-only discretization is considered intentionally to investigate its suitability for modeling of closed cell foams and trabecular bone.