Metal foams are a family of cellular materials with unique physical and mechanical properties. The high strength-to-weight ratio in these materials has made them an excellent candidate for many industrial applications. In addition, metal foams have a high energy absorption capacity. When these materials are subjected to pressure loading, they can absorb the input energy by the plastic deformation of the internal foam cells almost uniformly. Therefore, they are used for industrial applications where energy absorption and impact protection are required. In this thesis, the structure and mechanical properties of metal foams were investigated, and then, the behavior of these materials under different loads was studied using two dimensional finite element modeling in Abaqus software. In this modeling, to obtain the behavioral sensitivity of metal foams to density changes and loading rates, several aluminum foam samples of different densities were subjected to static and dynamic compressive loading with different strain rates. The modeling results show that the low density aluminum foam has little sensitivity to the loading rate. As the relative density of the foam increases, the sensitivity to the loading rate also increases and the energy absorbed by the aluminum foam increases. Furthermore, by examining the mechanism of foam cell collapse under different loading rates, a large difference was observed in the static and dynamic behavior of foam cell collapse. On the other hand, The equations governing the foam cell collapse were obtained using a simplified model of the foam cell. Finally, the effect of changes in the thickness of the foam cell wall and the strength of the foam constituent on its energy absorption behavior was investigated. Comparing the numerical results with available experimental results, a good agreement was observed. Keywords: Metal foam, Aluminum foam, Energy absorption
