Yan, Sikang (2024)
A phase field model for cyclic fatigue.
Technische Universität Darmstadt
doi: 10.26083/tuprints-00028817
Dissertation, Erstveröffentlichung, Verlagsversion

Kurzbeschreibung (Abstract)

Fatigue failure is one of the most crucial issues in manufacturing processes and engineering applications. Stress or displacement cycles can cause cracks to form and grow over time, eventually leading to structural failure. To avoid these failures, predicting fatigue crack evolution behavior in advance is important. In the past decade, the phase field method for fatigue analysis has drawn much attention. The biggest advantage of the phase field model is its uniform description of all crack evolution scenarios by one evolution equation. It has been shown that the phase field fatigue model can reproduce the most important fatigue properties and predict the crack growth path; however, it still comes up short of some complex problems in the industry. The first drawback of the phase field fatigue model is its intense computational cost since fatigue fracture usually happens after thousands of repeated cycles. In order to keep the simulation time within a reasonable limit, the cycle number increment is therefore adaptively chosen in the phase field simulation. Following that, we show that the phase field fatigue model can simulate complex loading situations including different loading temperatures and frequencies. We also extended the phase field model for thermomechanical fatigue, in which an additional fatigue driving force is considered. It is known that the phase field model is based on an energetic formulation, which can not be easily understood straightforwardly. Thus, we take the idea of configurational forces and provide a simple way to explain the energetic driving forces in the phase field fatigue simulation.

Frage zum Eintrag

Redaktionelle Details anzeigen