Damage-based low-cycle fatigue lifetime prediction of nickel-based single-crystal superalloy considering anisotropy and dwell types

摘要

Based on the physical phenomenon that the fatigue cracks initiate along specific slip plane, a slip plane damage-based low-cycle fatigue (LCF) lifetime model for the nickel-based single-crystal superalloy is established. The predicted results indicate that the lifetime model can reflect the orientation effect. In addition, in order to characterize the dwell-time dependence of the LCF lifetime, creep damage and compression-creep damage are introduced to the lifetime model. Finally, the lifetime predictions under LCF loading with tensile dwell time, compressive dwell time and tensile-compressive dwell time are conducted by employing the lifetime model, respectively. The predicted lifetimes show a good agreement with the experimental data, which verifies the accuracy of the developed lifetime model in this paper.