An enhanced mean field material model incorporating dislocation strengthening for particle reinforced metal matrix composites

An analytic model of predicting the elastoplastic stress-strain curve of particle reinforced metal matrix composites is proposed. This model is enhanced so that Mori-Tanaka method can be applied to bimodal or particulate metal matrix composites that exhibit size effects due to the dislocation strengthening mechanisms. The thermal misfit and mechanical misfit strains between the inclusion and the matrix are accounted for by this model. Several aluminum-based metal matrix composite as well as a bimodal copper system are examined and their yield strengths and stress-strain curves are compared with published experimental data. The proposed model is simple, yet quite effective and reasonably accurate.