Finite element analysis of elastic property bounds of a composite with randomly distributed particles

The bounds of the elastic properties of an E-glass particle reinforced BISGMA/TEGDMA composite were predicted by a random unit cell model. Two means of tensile loading were used: iso-displacement loading and iso-stress loading. The iso-displacement loading predicts the upper bound of Young's modulus, while iso-stress loading predicts the practical lower bound of Young's modulus. The results showed that Young's modulus increases, while Poisson's ratio decreases with increasing filler content for both loading conditions. For comparative purposes, the upper and practical lower bounds were also calculated by Hashin's method, a periodic three-dimensional single-particle, and two-particle unit cells. Analytical solutions using the Mori-Tanaka model and experiments were also conducted for verification purpose. The results showed that the random unit cell predicts better overall bounds for elastic properties.