Micromechanical analysis of aligned and randomly oriented whisker-/short fiber-reinforced composites

Abstract

This paper presents a micromechanical approach for predicting the elastic and multi-level damage response of aligned and randomly oriented whisker-/ short fiber-reinforced composites. Based on a combination of Eshelby's micromechanics and the evolutionary imperfect interface approach, the effective elastic moduli of the composites are derived explicitly. The modified Eshelby's tensor for spheroidal inclusions with slightly weakened interface [Qu (1993b)] is extended in the present study to model whiskers or short fibers having mild or severe imperfect interfaces. Aligned and random orientations of spheroidal reinforcements are considered. A multi-level damage model in accordance with the Weibull's probabilistic function is then incorporated into the micromechanical framework to describe the sequential, progressive imperfect interfaces in the composites. Numerical examples corresponding to uniaxial tensile loadings are solved to illustrate the potential of the proposed micromechanical framework for predicting the elastic and multi-level damage response of the composites. Furthermore, comparisons between the present predictions and experimental data in the literature are made to further highlight the capability of the proposed micromechanical framework.