Probabilistic fatigue modeling of notched components under size effect using modified energy field intensity approach

Abstract

Fatigue assessment in the presence of intricate geometries is critical for ensuring structural integrity and reliability of engineering components. Based on the energy field intensity (EFI) approach, this study establishes a probabilistic framework to predict fatigue life of notch components considering size effect. Specially, a new concept of effective damage zone (EDZ) is introduced based on characteristic total strain energy density (TSED), and the relation between EDZ and fatigue life under size effect was explored and quantified. Through combining the Weibull distribution, an EFI-based probabilistic assessment is conducted for fatigue failure probability analysis of notch components. Experimental data of Ni-based superalloy GH4169 and Al 2024-T351 alloy with different scales were utilized for model validation and comparison. Results indicate that the proposed framework yields good consistency with experimental lives.