Investigation of the Stiffness and Strength of Particulate Composites by Means of a Variant Cubic Model and SEM Fractography Microscopic Approach

In this article the stiffness of particulate composites is determined by the use of a multivariant three-phase model. This model consists of the transformation of spatial cubic models; it simulates a particulate composite into a three-sphere model, designating the two main phases of the composite material, the filler and the matrix, and applying the classical theory of elasticity to it. Theoretical results derived from this model are compared with experimental results derived from tensile tests carried out with iron particle reinforced epoxy resin composites and also with other theoretical results given by other researchers. In this context, an attempt is made to give, in a somewhat tentative way, a semiquantitative explanation of certain discrepancies observed between experimental data and the theory concerning the elastic modulus as well as experimental data concerning some fracture parameters on the basis of a macroscopic and a fractography-aided microscopic approach.