Abstract:

Physics-based models for fatigue damage.

Fatigue failure prognosis requires understanding the mechanical response of materials under myriads of service conditions. Most approaches that predict the response of metals rely on correlations between phenomenological formulations and macroscopic measurements, which demands time-consuming experimental programs. Furthermore, model fidelity rapidly decreases when the applied loading conditions depart from those use to calibrate the correlations.

Here we will present a physics-base crystal plasticity framework in which virtually all parameters can be quantified independently at micro- and mesoscales. The key value added relies on the low dependence on loading conditions of small scale damage mechanisms.  We will employ this approach to predictive fatigue damage in FCC metals by computing fatigue indicator parameters (FIPs) associated to crack nucleation.