Effects of transitional functions on multiscale fatigue crack growth

Transitional functions are the reflection of combined effects of material, loading and geometry through the process of fatigue crack growth. They are incorporated in the segmented multiscale model. Based on the formulated multiscale fatigue crack growth model, effects of transitional functions on the crack growth behaviors of superalloys are discussed. Considering the inevitable assumption on the three transitional functions, the uncertainties of coefficient variation remains to be clarified. Material, loading and geometry effects are separately studied on the basis of collected test data of 2024-T3 Al sheet. Consequently, three transitional functions are optimally determined. These findings offer a new perspective of combined material, loading and geometry effects on crack growth behaviors of superalloys.