Predicting Fatigue Crack Retardation Following a Single Overload Using a Modified Wheeler Model

A modification to the Wheeler fatigue crack retardation model is proposed. The modification allows the model to be used without reliance on data fitting and, therefore, without the subsequent limiting to a specific material or to a specific set of loading parameters. The new model is used to predict existing data for the number of delay cycles following a single overload in 2024-T3 aluminum, 4340 steel, and Ti-6Al-4V titanium alloy. All predictions were within essentially a factor of two of the experimental data.