A creep-fatigue crack growth model containing temperature and interactive effects

A trinomial superposition model containing a temperature parameter and accounting for creep-fatigue interactive effect for predicting creep-fatigue crack growth rates is proposed in this paper. Items and parameters in the model are investigated via fatigue crack growth experiments with 0 s and 90 s dwell time at different elevated temperatures on a nickel-based powder metallurgy superalloy FGH97. The results indicate a good capability of the proposed model in correlating the crack growth rate with creep-fatigue interactive effect. The model is also validated by available test results of Alloy 718 at 550 °C and 650 °C with various dwell times.