Nonlocal plasticity effects on the tensile properties of a metal matrix composite

For a metal reinforced by aligned short fibres the effect of a material len gth scale characterising the inelastic deformations of the metal is studied . The elastic-plastic constitutive relations used here to represent the non local effects are formulated so that the instantaneous hardening moduli dep end on the gradient of the effective plastic strain. Numerical cell-model a nalyses are used to obtain a parametric understanding of the influence of d ifferent combinations of the main material parameters. The analyses show a strong dependence on the fibre diameter for given values of all other mater ial parameters, and it is shown that this dependence differs somewhat for d ifferent values of the fibre aspect ratio. (C) 2001 Editions scientifiques et medicales Elsevier SAS.