An improved critical plane-energy multiaxial fatigue life prediction model considering shear mean stress

In the present research, the effects of normal mean stress acting on fatigue evolution are considered well in critical plane multiaxial models, whereas shear mean stress effects have rarely attracted attention. These models may result in nonconservative predictions under asymmetric loadings with substantial shear mean stress. Therefore, an improved critical energy model is introduced to solve multiaxial fatigue issues on the basis of the Fatemi-Socie model and the Walker model, which consider normal mean effect, shear mean stress effect, and additional hardening effect. Moreover, experimental data from GH4169, wrought Ti-6Al-4V, and TC4 are employed to validate the proposed model. Results show that the proposed model can reasonably predict fatigue life under various loadings, particularly for asymmetric loadings.