- Titel
- Phase-field modeling of fatigue fracture
- Zitierfähige Url:
- https://nbn-resolving.org/urn:nbn:de:bsz:14-qucosa2-944738
- Schriftenreihe
- Veröffentlichungen des Instituts für Festkörpermechanik
- Bandnummer
- 11
- Erstveröffentlichung
- 2024
- Datum der Einreichung
- 21.05.2024
- Datum der Verteidigung
- 08.10.2024
- ISSN
- 2702-6787
- Abstract (EN)
- Fatigue fracture is one of the main causes of failure in engineering structures. However, its simulation still remains a challenge. To this end, an efficient phase-field model for fatigue fracture is introduced. The phase-field method regularizes the crack description and allows for a straight-forward simulation of crack initiation and arbitrary crack patterns. The effects of fatigue are included in the model via the Local Strain Approach. This concept introduces assumptions on the cyclic stress-strain behavior and the fatigue resistance of the material, making use of experimental cyclic material data. In this way, the phase-field model can remain elastic, while the introduced fatigue damage still includes cyclic plasticity in a simplified way. Therefore, the model reduces computational time significantly compared to other phase-field fatigue models, also, because it can cover several load cycles in just one computation increment. The model is parametrized and validated for aluminum sheet material and proves to be able to reproduce the typical fatigue crack growth behavior of this material. Details on the implementation are provided. The model is presented in a general framework for phase-field models for fatigue fracture, which is also used for a comprehensive overview and classification of existing models in the literature. The model is extended to deal with residual stresses in the material, which exert great influence on the fatigue crack growth behavior, as experiments and simulations show consistently. Also, anisotropic material properties are included through yet another model extension. Particularly, the direction-dependent fracture toughness of rolled aluminum sheets is considered. Simulations reproduce characteristic crack paths caused by this anisotropy. Finally, the model's assumptions regarding cyclic plastic material behavior are put to a test. To this end, a phase-field fatigue ansatz with elastic-plastic material model of Armstrong-Frederick type is implemented. It serves as a reference to define the range of application of the efficient, yet simplified fatigue model presented in this thesis.
- Freie Schlagwörter (EN)
- FEM, Phase-field, Fracture, Fatigue, Ductile
- Klassifikation (DDC)
- 620
- Klassifikation (RVK)
- ZL 3255
- GutachterIn
- Prof. Dr. Markus Kästner
- Prof. Dr. Stefan Löhnert
- Herausgeber (Institution)
- Institut für Festkörpermechanik, Dresden
- Den akademischen Grad verleihende / prüfende Institution
- Technische Universität Dresden, Dresden
- Förder- / Projektangaben
- Deutsche Forschungsgemeinschaft Experimental analysis and phase-field modelling of the interaction between plastic zone and fatigue crack growth in ductile materials under complex loading
ID: KA 3309/12 - Version / Begutachtungsstatus
- publizierte Version / Verlagsversion
- URN Qucosa
- urn:nbn:de:bsz:14-qucosa2-944738
- Veröffentlichungsdatum Qucosa
- 11.12.2024
- Dokumenttyp
- Dissertation
- Sprache des Dokumentes
- Englisch
- Lizenz / Rechtehinweis
CC BY 4.0