Simulating Fatigue Crack Growth including Thermal Effects Using the Phase Field Method

Abstract

Putting a mechanical structure under repeated cyclic loading can lead to fatigue crack initiation and propagation in materials. In engineering processes, a fatigue crack evolution behavior can be very complicated when the structure is in a complex environment. It has been shown that internal friction is one of the most important factors for the fatigue behavior of materials. However, there is still a lack of studies on how to predict the influences of internal friction on fatigue crack evolution. In this work, we show that the phase field model provides an elegant solution for structures under different loading frequencies and temperatures. Although the phase field fatigue model has been studied for years for mechanical loading situations, the question of how to include thermal fatigue effect remains open. In this work, we add thermal stresses to the phase field model as the second fatigue driving force. It is shown that the model is able to predict thermal fatigue behavior.

Overview of phase-field models for fatigue fracture using a unified framework

“…See Section 4.7 for more details. This model was extended to incorporate thermal effects in Yan et al [50].…”

“…• Elastic: Carrara et al [27], Grossmann-Ponemon et al [37] • Bauschinger effect (kinematic hardening): Aygün et al [25], Seles et al [40], Ulloa et al [20], Khalil et al [44] • Ratchetting: Ulloa et al [20] • Temperature-dependent fatigue behaviour: Amendola et al [46], Haveroth et al [53], Yan et al [50] • Acceleration techniques for computational time: Seiler et al [35], Seles et al [40], Schreiber et al [48], Loew et al [22], Haveroth et al [53], Lo et al [26] • Concentration-dependent material behaviour: Ai et al [62] implemented a coupled chemo-mechanical fatigue fracture model to simulate cracking in lithium-ion batteries. The phase-field fatigue part is equivalent to Carrara et al [27].…”