Fatigue limit prediction with simulated cyclic resistance curves

A novel method to predict the fracture-mechanical fatigue limit based on simulated cyclic resistance curves is presented. Plasticity-induced crack closure development, whose role in the fatigue limit analysis is emphasized due to its fast saturation, is modeled for short cracks under near-threshold loading via finite element analysis. Combined with the intrinsic threshold, the cyclic R-curve can be derived from the simulated crack closure response. The fatigue limit from crack arrest is determined by the tangency condition between nominal crack driving force and the cyclic R-curve. The fatigue limits predicted as a demonstration of the method are consistent with literature knowledge. The method can be employed to any geometry, material, crack, or loading configuration.