Fracture onset in sheet metal forming : a comparison between a finite element damage model and a post-processing plastic instability code

Abstract

Necking prediction in sheet metal forming is an important demand from industry, since such assessment defines the success of a stamping process. This paper presents two numerical approaches for failure prediction in sheet metal forming operations: the implementation of the Lemaitres ductile damage model in the Abaqus/Explicit code in accordance with the theory of continuum damage mechanics and the traditional use of FLDs, usually employed as an analysis of the finite element solution in which the necking phenomenon is carried out in the framework of Marciniak-Kuczinsky (M-K) analysis coupled with the conventional theory of plasticity. The previous strategies and corresponding results are compared with two experimental failure cases, in order to test and validate each of these strategies