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Modelling stress‐state dependent nonlocal damage and failure of ductile metals
Author(s) -
Nahrmann Marvin,
Matzenmiller Anton
Publication year - 2021
Publication title -
pamm
Language(s) - English
Resource type - Journals
ISSN - 1617-7061
DOI - 10.1002/pamm.202000054
Subject(s) - void (composites) , coalescence (physics) , materials science , hydrostatic stress , ultimate tensile strength , mechanics , nonlinear system , hydrostatic equilibrium , structural engineering , composite material , finite element method , physics , engineering , quantum mechanics , astrobiology
Abstract Damage and failure of ductile metals is highly influenced by the stress state. In fact, void growth takes place under hydrostatic tensile loading and void coalescence leads eventually to ductile failure. A completely different damage mechanism occurs for shear dominated loading that results in void elongation within a narrow shear band. In order to account for both failure mechanisms, a stress state dependent damage model is proposed. The model is based on a continuum damage mechanics approach, whereby nonlinear damage evolution is taken into account. The influence of the stress triaxiality and the LODE parameter on damage initiation and failure is considered by the Hosford‐Coulomb model. Pathological mesh sensitivity is prevented by an integral type nonlocal formulation. Finally, the proposed stress‐state dependent nonlocal damage model is verified by test data for the microalloyed high strength steel HX340LAD for a wide range of stress states.