This paper was produced for the 2019 NAFEMS World Congress in Quebec Canada

Resource Abstract

A finite element representative volume element (FE-RVE) model is developed for the microstructure of an auxetic resilient foam using 3D tomography data. Simulations are performed on these FE-RVE models in which they are subjected to various large, multiaxial far-field strains. Self-contact, large deformation, and material nonlinearity is accounted for, and the volume average stress response under each loading history is obtained. These volume-average stress-strain responses are then used in an optimization process to calibrate a phenomenological hyperfoam material model which closely reproduces the effective homogenized behavior of the foam microstructure, and which can be used to model the foam as a homogenized continuum in larger scale FE simulations. The optimization process includes a novel stability constraint which ensures the resulting hyperfoam model exhibits stability over a broad range of deformations.