Effective Moduli of Coated Particulate Composites with BCC Structure at High Concentration

Abstract

A micromechanical approach for an accurate estimation of the effective moduli of composites reinforced with nondilute distribution of coated particles is developed. The theory is based on the extension of the equivalent inclusion method to interacting multiinhomogeneities. In this treatment the short and long range interactions of the reinforcing particles are appropriately incorporated through the homogenizing eigenstrain field. The periodicity of the microstructure of the medium suggests representing the eigenstrain field in terms of the Fourier series, accounting for the matrix–particle, interparticle, and intraparticle interactions with high precision. The proposed theory is valid for estimating the overall properties of solids containing thickly and/or functionally graded coated reinforcements. For demonstration, the problems of composites with body centered cubic (BCC) distribution of coated spherical particles as well as coated ellipsoidal particles are solved. The effect of volume fraction, coating thickness, coating stiffness, and shape and orientation of the coated ellipsoidal reinforcements on overall behavior of composites are thoroughly examined.