A general energy-based model for fatigue life prediction of high-temperature structural materials

Abstract

Improved fatigue life prediction methods will assist in reducing life cycle costs and increasing the availability of mechanical components. These methods include Stromeyer function, Basquin law, Manson-Coffin law, frequency modified damage function (FMDF) model, strain range partition (SRP) and so on. However, different models are applied to assess the life under high cycle fatigue (HCF) and low cycle fatigue (LCF). This is a domain of concern in the development of fatigue life prediction models which contain combinations of HCF and LCF. In this paper, based on the Manson-Coffin law and an energy-based damage parameter, a general energy-based model is presented to predict fatigue life under both HCF and LCF conditions. By correlated with the energy-based damage parameter to the test data of superalloys GH901 and K403 in existing literatures, the lives predicted by the proposed model are compared with experimental results resulting in a good agreement.