2 - A mechanisms-based framework for describing failure in composite materials

Abstract

Failure in composite materials is a local phenomenon, whose mechanisms are governed by the local (microscopic) fields. This chapter reviews first the composite failure theories that are formulated on the macroscopic scale, that is, where composite materials are regarded as homogeneous, anisotropic solids. By examining the fundamental assumptions of such theories, exemplified by a few selected and commonly used ones, the inherent limitations of the theories are clarified. A mechanisms-based framework for describing failure in composite materials is then treated. The basic elements of this framework, multiscale failure analysis, account of constraints by the local environment on the failure behavior, and incorporating manufacturing defects as an integral part of the material state, are described.