Discussion des critères macroscopiques de rupture recherche d’un critère macroscopique d’amorçage

Discussion of the macroscopic fracture criteria. In search of a macroscopic initiation criterion

Ecole des Mines. Centre de mise en forme des matériaux, Sophia-Antipolis GRECO « Grandes déformations et endommagement ».

Abstract

The criteria for ductile fracture proposed by Latham and Cockroft and by Oyane are applied to the following deformation paths: simple shear then uniaxial tension (C + T), or the opposite (T + C). The results of both criteria are very similar, the path C + T giving a smaller total equivalent strain. The shapes of the critical curves for decohesion obtained from a microscopic model suggest the formulation of a macroscopic criterion for the initiation of damage similar to the macroscopic criteria for fracture.