Finite-Element Simulation of Elastoplastic Properties of Two-Phase Composites Reinforced by Particles

Abstract

The determination of elastoplastic properties of composite materials is a rather complicated problem. Analytical approaches to the solution of the problem available in the literature [1–3] are based on a number of simplifying assumptions which allow the distribution of local fields of displacements, strains, stresses in a composite to be described in terms of a small number of parameters (degrees of freedom). For example, for the construction of a composite model under elastoplastic deformation, Dvorak and Bahei-El-Din [1] and Levitas [3] assumed a uniform distribution of local fields of strains and stresses in each phase of a composite (i.e. one parameter or degree of freedom was used to describe strains and stresses in each phase). Aboudi [2] obtained elastoplastic properties of a two-phase composite analytically using the method of cells with four subcells. For each subcell a linear variation of the displacements was accepted (i.e. three and twelve parameters or degrees of freedom were used to describe a field of each component of displacement vector for the subcell and the cell, respectively). These models can give overestimated values of macroscopic stresses. The question is open whether simplified models with a small number of degrees of freedom for description of local fields of displacements, strains and stresses in each phase can give results of high accuracy under elastic and elastoplastic straining.