Effective elastoplastic behavior of metal matrix composites containing randomly located aligned spheroidal Inhomogeneities. Part II: applications

Based on the proposed formulation in Part I of this sequel (Ju, J.W., Sun, L.Z., Int. J. Solids Struct. 38, 183±201), e€ective elastoplastic constitutive relations are implemented in this article for metal matrix composites (MMCs) with randomly located and unidirectionally aligned spheroidal particles. First, we investigate the uniaxial elastoplastic stress±strain behavior of MMCs. In particular, we perform comparisons among the theoretical uniaxial stress±strain predictions, existing ®nite element results and experimental data for MMCs to illustrate the capability of the proposed method. Furthermore, the e€ect of stress triaxiality is discussed under either the purely hydrostatic or axisymmetric loading on the overall elastoplastic behavior of composites. The proposed initial e€ective yield surfaces for composites are demonstrated and compared with those of the experimental data. As a special case of the incompressible ductile material containing aligned spheroidal voids, the initial e€ective yield criterion is studied and compared with that of mathematical upper bound. Finally, viscoplastic extension is brie¯y presented. Ó 2000 Elsevier Science Ltd. All rights reserved. Keywords: Micromechanics; Elastoplasticity; Metal-matrix composites; Random microstructure