A New Model for Predicting the Creep-Fatigue Life under Stepped-Isothermal Fatigue Loading

This paper proposes an isothermal fatigue life prediction model to predict the fatigue life of the creep-fatigue damage interaction. The fatigue life is caused by high-frequency mechanical loads and low-frequency temperature loads, i.e. stepped-isothermal fatigue loads. The model is based on continuum damage mechanics (CDM), in which the interaction between creep and fatigue damage is considered nonlinear. To verify the proposed model, the cast aluminum alloy is subjected to fatigue tests at 200-350 degrees C. The results show that the predicted life of the model can reach a good consistency with the experimental data.