Creep Damage Assessment and Lifetime Predictions for Metallic Materials under Variable Loading Conditions in Elevated Temperature Applications

摘要

In this paper the problem of creep damage assessing as well as of creep life prediction of metallic materials under variable loading conditions is considered. A non-linear model for creep damage accumulation which is based on a more general physical-phenomenological model describing the mechanical behaviour of metallic materials under creep conditions, is presented. The model is suitable for the prediction of the creep damage accumulation under variable load and/or temperature. The proposed model takes into account the previous damage history and, definitely, the loading order. In any case the creep strain accumulation is taken into account as this is directly associated with the creep damage accumulation. Theoretical results agree well with the experiments.