A mesoscopic model for inelastic deformation and damage

The micro-mechanical behavior and damage of materials containing multiple m icrocracks is investigated using a mesoscopic approach. We develop an analy tical and computational framework for the nucleation and interaction of mic rocracks near a macrocrack tip based on both the theory of elasticity and t he theory of dislocations. Grain boundaries are considered as critical mate rial points for crack initiation. The discrete model is used to investigate the relationship between the macroscopic applied stress and evolution of m icrocracks, yielding a micro-structurally based model for the evolution of damage consistent with some theoretical models. It is suggested that with t his approach macroscopic models can be developed whose phenomenological par ameters can be rigorously investigated and obtained using discrete simulati on of microcracks. (C) 2001 Elsevier Science Ltd. All rights reserved.