Computational Approach of Dielectric Permitivities in BaTiO3--Epoxy Composites

A numerical approach using a finite element method (FEM) was performed in order to determine the dielectric constant (epsilon') of BaTiO3-epoxy composites. In order to diminish computational resources and analyse simple models, composite topology was represented by periodic structures based on FCC configurations, but introducing novel packaging protocols, defining the way composites are filled as particle concentration is increased. The dielectric response of these anisotropic and periodic structures was mathematically represented through a quasi-static approximation using the Laplace equation. The amount of inclusions was varied in order to represent diluted and concentrated systems and structures were assessed for the whole feasible range of volume fractions. The numerical results were compared with experimental data concluding that only packaging protocols that consider higher particle-particle interaction are suitable to represent the dielectric behavior of concentrated-composite materials.