Coupling of micro- and macro-damage models for the simulation of damage evolution in ductile materials

Abstract This research presents a new simulation concept of damage evolution for metallic materials under large deformations. The complete damage range is subdivided into both the micro- and macro-damage range. The micro-damage phase is described by the Cocks-Ashby void-growth model for isotropic, ductile materials under isothermal conditions. After having reached a critical void-volume fraction, a macro crack is introduced into the model. Applying the finite element method for the numerical formulation, at every incremental macro-crack step the finite element mesh is adapted such that the crack path remains independent of the initial mesh. With this concept the damage evolution from nucleation and growth of micro-voids to initiation of macro cracks and complete failure of the material can be described.

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