Influence of particle arrangement on the stiffness and thermal expansion coefficient of aluminium-epoxy composites

The stiffness and thermal expansion coefficient of periodic polymer composites containing identical spherical particles are studied using micromechanics principles. A cubic unit cell has been considered to predict thermomechanical properties of particulate polymeric composites. This model takes into account the influence of the distribution (arrangement) of spherical inclusions on the thermomechanical constants of the composite material consisting of matrix and filler. A composite model derived from the cubic and face-centred cubic model representing the basic cell of the composite at a microscopic scale was transformed into a five-phase spherical representative volume element (which will be referred henceforth as R.V.E.), in order to apply the classical theory of elasticity to it. Theoretical values arising from this proposed model were compared with experimental results carried out with epoxy resin composites filled with aluminium particles and also with those obtained from other theoretical formulas derived by other scientists.