FINITE ELEMENT ANALYSIS OF QUASI-STATIC CRUSH ENERGY IN CLOSED CELL ALUMINUM FOAM USING VORONOI TESSELLATION

A novel Voronoi closed-cell foam model was developed to perform finite element analysis (FEA) to accurately capture the stress-strain behaviors exhibited by real foam blocks under uniaxial crush. The cellular structure of aluminum foam was imaged, and then two software packages, LAMMPS and Voro++, were used to construct a detailed Voronoi tessellation of the microstructure and porosity of the foam. This tessellation was then refined in MATLAB, where density adjustments created a representative base matrix of Voronoi cells. Using a further software package, NX12, the final Voronoi foam model was refined to efficiently apply FEA. In ABAQUS, multi-step FEM techniques were used to simulate the load-stroke profile under quasi-static crush. The stress-strain curve predicted from this FEA closely mirrored the data from our quasi-static crush tests, so that the Voronoi tessellation-based closed-cell foam model was effective at predicting energy absorption under crush. The Voronoi tessellation enables perturbations in cell size distributions, foam density, and material composition within the FEA framework, so that aluminum foams can be designed for specific load vs. stroke requirements.