Effect of Overload on the Near-Threshold Fatigue Crack Growth Rate in a 2024-T3 Aluminum Alloy: II. Fatigue Crack Growth Simulation for Calculating the Fatigue Life under Alternating Loading

The results of overloading and underloading tests of aluminum specimens in near-threshold crack growth rate range are considered. A combined model is proposed to take into account crack closure and the influence of the local stresses at the crack mouth. The model is based on the Neuber and Ramberg–Osgood equations and can be used to estimate the fatigue life of crack growth in the near-threshold range. This model is grounded from a physical standpoint.