A path-dependent multiaxial fatigue life estimation criterion for metals under various loading conditions

Abstract In this research, a new life reduction index is proposed for life prediction with the consideration of material’s non-proportional fatigue life reduction process. The new index has been deduced based on the Fatemi-Socie damage parameter. For the centro-symmetric loading, the proposed index can be applied to assess the fatigue life of material without requiring the complicated multiaxial constitutive algorithm, no matter whether the material is sensitive to the non-proportional hardening or not. The prediction accuracy and robustness of the proposed index has been extensively validated using about 1059 experimental data by testing 25 materials under 18 different loading paths