A Fatigue Performance Analysis Framework for Evaluating Fatigue Behavior in Metallic Materials: From Notch Fatigue to Crack Propagation

Critical engineering components inevitably develop various types of notches during the design and production process. A comprehensive assessment of notch fatigue using an appropriate fatigue analysis framework is crucial for the structural integrity, operational reliability, and antifatigue design of critical components. In this study, by combining plasticity reformulated of critical distance, Atzori–Lazzarin diagram, and the cyclic R-curve, a new fatigue analysis framework including notch fatigue to crack propagation is elaborated. In the first part of the framework, an explicit notch fatigue model is proposed to describe notch geometry and microstructure effects. In the second part, a new cyclic R-curve equation without data-fitting parameters is established and extends it to fatigue crack growth (FCG) prediction. Experimental data from eight metallic materials are used to validate the proposed models, and the results demonstrate the framework's generality and accuracy.