Parameter estimation of a high-cycle fatigue model combining the Ottosen-Stenström-Ristinmaa approach and Lemaitre-Chaboche damage rule

This paper deals with the continuum approach to the high-cycle fatigue model introduced by Ottosen et al. equipped with the damage rule of Lemaitre and Chaboche. The main result is that model parameters K and γ are not identifiable based on lifetime data. However, with observations from a fatigue development profile, it is possible to estimate also the γ-parameter. Moreover, the model gives the same lifetime for all γ⩾0. These results are elucidated with examples.