Diffuse-interface modeling of composition evolution in the presence of structural defects

A diffuse-interface phase field model is described for modeling the interactions between compositional inhomogeneities and structural defects, The spatial distribution of these Structural defects is described by the space-dependent eigenstrains. It takes into account the effect of the coherency elastic energy of a compositional inhomogeneity, and the elastic coupling between the coherency strains and defect strains. The temporal evolution of composition is described by the Cahn-Hilliard equation. Particularly. the solute segregation. and nucleation and growth around dislocation slip hands and crack-like condensed interstitial dislocation loops are discussed. The effect Of nucleated coherent precipitates on the stress field around these defects is analyzed. (C) 2002 Elsevier Science B.V. All rights reserved.