Speaker
Description
Phase-field modelling of fatigue fracture has been approached by many different models in recent years. Yet due to the high number of load cycles involved, computational time remains one of the main challenges, especially for fracture in ductile materials such as metals.
In this contribution, we revisit our efficient phase-field model for fatigue fracture [1] with a simplified consideration of cyclic plasticity. We combined the phase-field method for brittle fracture with the Local Strain Approach [2], a traditional fatigue concept from structural durability. It involves assumptions for the stress-strain behaviour including local plasticity and the damaging effect of load cycles, based on experimental material data.
Now, we improve the model by refining both the approximation of the stress-strain behaviour and the evaluation of the damaging effect of the load cycles with a new damage parameter. In a second step, we introduce a comprehensive phase-field model with elastic-plastic material law [3]. This we use to evaluate the two efficient models with the simplified integration of plasticity. The range of application of the three models is discussed, compromising between accuracy and computational time. The results of the comparison are published in [4].
[1] Kalina, M., Schöne, V., Spak, B., Paysan, F., Breitbarth, E., Kästner, M. (2023). Fatigue crack growth in anisotropic aluminium sheets -- Phase-field modelling and experimental validation. International Journal of Fatigue, 176, 107874.
https://doi.org/10.1016/j.ijfatigue.2023.107874
[2] T. Seeger, Grundlagen für Betriebsfestigkeitsnachweise, Stahlbau-Handbuch. Vol. 1 Teil B (1996) 5-123.
[3] Ulloa, J., Wambacq, J., Alessi, R., Degrande, G., François, S. (2021). Phase-field modeling of fatigue coupled to cyclic plasticity in an energetic formulation. Computer Methods in Applied Mechanics and Engineering, 373, 113473.
https://doi.org/10.1016/j.cma.2020.113473.
[4] Kalina, M., Schneider, T., Waisman, H., Kästner, M. (2024). Phase-field models for ductile fatigue fracture (arXiv:2411.05015). arXiv. http://arxiv.org/abs/2411.05015
