Effect of Overload on the Near-Threshold Fatigue Crack Growth Rate in a 2024-T3 Aluminum Alloy: I. Effect of the Character, the Magnitude, and the Sequence of Overload on the Fatigue Crack Growth Rate

Resumo

The results of overload and underload tests on aluminum specimens in the near-threshold crack growth rate region are discussed. These tests are performed to choose a model for predicting the fatigue life. The influence of the character and the magnitude of overload and underload on the fatigue crack growth time is analyzed. The obtained crack growth curves and the fatigue lives cannot be explained in terms of classical models, which makes it necessary to develop a new model.