AN ESHELBY INCLUSION BASED MODEL FOR THE STUDY OF STRESSES AND PLASTIC STRAIN LOCALIZATION IN METAL-MATRIX COMPOSITES .1. GENERAL FORMULATION AND ROUND PARTICLES

The macroscopic behavior of metal matrix composites is certainly influ enced by he localization of stresses and strains in the vicinities of inclusions. The Eshelby model has been extended to handle incipient pl astic deformation in the vicinities of inclusions following a Prandlt- Reuss plastic law. It allows, by using a novel convergence criterion, to find the solution for the elastoplastic field in the general case o f ellipsoidal particles under thermal and mechanical loading. The form ulation is applied to a model case of Al matrix reinforced with SiC ro und particles. Both matrix and particles are considered elastic and th ermally isotropic and the matrix flows when it reaches an isotropic yi eld stress. it is found that the results agree with previous FEM calcu lations and the method allows to study local plastic relaxation when m echanical loading is below the matrix macroscopic yield stress.