Events
Mechanisms and modelling of fatigue crack growth under combined low and high cycle fatigue loading
Date: 15.12.2009Place: UHW 11/1102
Christoph Schweizer, Abteilung Lebensdauerkonzepte, Thermomechanik, Fraunhofer-Institut f. Werkstoffmechanik IWM, Freiburg, Germany
The evolution of microcracks in a 10%-chromium steel is followed with the replica technique for pure low cycle fatigue (LCF) and combined LCF and high cycle fatigue (HCF) loading conditions. The superimposed HCF-cycles lead to accelerated fatigue crack growth rates, as soon as a certain crack length is reached. A mechanism based model is presented, which accounts for this e ffect and only needs one single fitting parameter. The model is used to predict fatigue lives at high temperatures and under thermomechanical fatigue loading conditions.
