Experimental and FE Analysis of Quasi-Static Bending of Foam-Filled Structures

Three-point bending under quasi-static loading was carried out on empty and partially foam-filled tubes. ALPORAS® aluminum foam was used as an insert with aluminum alloy tube in the experiment. The experiment was modeled using the finite element (FE) code software package LS-DYNA®. The Deshpande-Fleck constitutive model was implemented in the simulation to model the foam. Its material parameters were calibrated against experimental data. The material parameters for the tube were also derived experimentally. Experimental data showed increase in specific energy absorption of approximately 17% whilst the lowest generator of the tube was found to increase by approximately 14% with inclusion of partially filling foam. The FE simulations compared well with the experiments, with the load-displacement and LG-indenter displacement agreeing within approximately 15%. Visual inspection of the foam showed local densification around the point of indentation. Similar features were seen in the FE simulation with high strains and large deformation present near the point of indentation. The results thus indicated a localized effect in energy absorption of the foam in the scenario being studied.