Effects of creep and oxidation to thermomechanical fatigue life assessment for nickel-based superalloy

The present work focuses on the quantification of creep and oxidation effects in the prediction of both isothermal and thermomechanical fatigue life for a nickel-based superalloy. The creep damage was evaluated using the time-fraction method and the ductility-exhaustion method. A diffusion-dominated environmental damage parameter was proposed based on the mechanism of oxygen-assisted intergranular cracking and applied to thermomechanical fatigue life assessment. The results revealed that creep damage appears to be negligible and environmental damage seems more dominant in the current study. The proposed model provides a unified description for both isothermal and thermomechanical fatigue.

Automated summary

This study focuses on quantifying creep and oxidation effects to predict isothermal and thermomechanical fatigue life in a nickel-based superalloy. Creep damage was evaluated using the time-fraction method and the ductility-exhaustion method. A diffusion-dominated environmental damage parameter based on oxygen-assisted intergranular cracking mechanism was proposed and applied to thermomechanical fatigue life assessment. The results suggest that creep damage is negligible while environmental damage appears to be more dominant in this study. The proposed model provides a unified description for both isothermal and thermomechanical fatigue.