Interface energy effect on effective elastoplastic behavior of spheroidal particle reinforced metal matrix nanocomposites

Abstract

A nanomechanical framework is proposed to predict the effective elastoplastic behavior of the metal matrix nanocomposites (MMNCs) containing randomly distributed and randomly oriented spheroidal particles. The interface energy effect is investigated by considering both of the interface elastic stress and the interface residual stress on the idealized zero-thickness membrane interphase between the matrix and the inhomogeneities. The orientational average is performed to obtain the effective constitutive relations of the MMNCs with randomly oriented spheroidal particles. By employing the micromechanical homogenization approaches, an effective yield criterion is formulated, and the effective secant moduli of the MMNCs are derived. Comparisons are made between the present framework and the classical micromechanics theory. The interface energy effect on the effective secant moduli are discussed, and the particle size dependence of the effective secant moduli is revealed. Furthermore, the effects of the interface elastic stress and the interface residual stress on the plastic yielding of the nanocomposites are discussed. Lastly, the theoretical predictions obtained by the present framework are compared with the relevant experiments and numerical simulations.