Resumo (PT):
Abstract (EN):
Reliable metal forming predictions require that fracture indication be available both in processes where it should be avoided and in processes in which fracture is a part of the process itself as in sheet blanking or metal cutting. The present proposal circumvents the necessity of the so-called "fracture indicators" or fracture criteria by representing fracture through the material model exclusively. The frequent objections to this otherwise attractive are mainly related to the observed defect of mesh dependency. To attenuate this dependency an implicit gradient damage model is used. Therefore a non-local damage field is introduced, which can be related to a local damage field, by means of a Helmholtz type differential equation. The damage evolution law is based on the improved Lemaitre damage model that treats differently the compressive and tensile response, which is particularly adequate for situations involving complex strain paths.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
6