Creep-Fatigue Life Prediction and Reliability Analysis of P91 Steel Based on Applied Mechanical Work Density

摘要

A creep-fatigue (CF) life prediction model and its simplified expression were developed based on the applied mechanical work density (AMWD). The foundation of this model was an integration of N-S curve. Comparisons of the model predicted fatigue lifetimes with the experimental data of load-controlled CF tests on P91 base metal and welded metal at 848 K from the reference were made and apparently illustrated that the model predictions were in a good agreement with the experimental fatigue lifetimes. In addition, the curve of the numbers of cycles to failure versus AMWD at the associated probability was deduced. A reliability model was constructed by combining the curve and the simplified life prediction model.