Multi-Scale Modeling and Simulation of Metallic Foams
Metallic foams show mechanical properties such as high energy absorption capacity as well as high specific strength and stiffness. In the present work simulations of the mechanical responses of cellular metals are carried out at different length scales. At the length scale of individual cells, cell walls, struts, and vertices, models of the cellular microstructure are examined with the Finite Element method in combination with unit cell approaches, providing information on the local deformation behavior, for example in the form of overall yield surfaces or the effective behavior under multiaxial loading conditions. Advantageous and detrimental topologies and values of microgeometrical parameters are identified for supporting materials design and development. At the level of samples and components constitutive models for metallic foams are evaluated with regard to their performance in simulating impact tests related to passenger protection in motor vehicles. Additionally, an efficient algorithm for the optimization of foam density distributions is presented.