Interface energy effect on effective elastic moduli of spheroidal particle-reinforced nanocomposites

Abstract

By incorporating the interface energy effect into a classical micromechanics framework, effective elastic moduli of a composite material containing randomly distributed nanosized prolate spheroidal inhomogeneities are investigated in this paper. The effect of interface energy, which is usually neglected in classical micromechanics theories, becomes important when the size of the reinforcement phase in the composite enters the nanometer range. The interface energy effect is simulated by inducing interface stress on the zero-thickness membrane interface between the matrix and the inhomogeneities. The interfacial stress discontinuity equations are formulated in accordance with the equilibrium conditions on the idealized interface, from which the interfacial strain discontinuity is solved. Subsequently, the effective elastic moduli are derived based on the classical micromechanics homogenization approaches. Comparisons are made of the effective moduli under the current nanomechanical framework and under classical micromechanical theory. The effective moduli are shown to be dependent upon the size of the inhomogeneities and the interface properties when the interface energy effect is considered.