Life modeling of anisotropic fatigue behavior for a single crystal nickel-base superalloy

• Conduct the fatigue tests of the SC superalloy at 760 and 980 °C, respectively.
• Propose the modified Mücke’s model to predict the LCF life for SC superalloy.
• Improve the life prediction level offered by the modified Mücke’s model.
• The modified model is based on the failure mode and has a clear physical meaning.

Strain-controlled low cycle fatigue (LCF) experiments of a second generation single crystal (SC) nickel-base superalloy are carried out to investigate the effect of crystallographic orientations on its LCF life. Further, the life modeling of the SC superalloy is considered by employing the modified Mücke’s anisotropic model. The results show that the LCF life of the SC superalloy has a strong crystallographic orientation dependence; the local strain approach fails to predict the fatigue life but the modified Mücke’s anisotropic model is able to predict the fatigue life for the SC superalloy at the three characteristic orientations simultaneously.