A MICROMECHANICAL MODEL OF INFLUENCE OF PARTICLE FRACTURE AND PARTICLE CLUSTER ON MECHANICAL-PROPERTIES OF METAL-MATRIX COMPOSITES

A general analytical model for a composite with an isotropic matrix an d two populations of spherical inclusions is proposed. The method is b ased on the second order moment of stress for evaluating the homogenis ed effective stress in the matrix and on the secant moduli concept for the plastic deformation. With Webull's statistical law for the streng th of SiCp particles, the model can quantitatively predict the influen ce of particle fracture on the mechanical properties of PMMCs. Applica tion of the proposed model to the particle cluster shows that the part icle cluster has neglected influence on the strain and stress curves o f the composite. (C) 1998 Elsevier Science B.V.