Fatigue crack growth behavior of AA2024T3 under mixed mode loading within the framework of EPFM

In this paper, a fatigue crack growth (FCG) behavior under variable amplitude loadings and for mixed modes is analyzed in terms of residual compressive stress zone. For that, the Chaboche non-linear kinematic hardening model is used to evaluate the crack behavior on AA2024-T3. At first, a series of FCG simulation is performed for a single edge notched tension specimen to highlight the influences of the crack length, the overload ratio, the stress ratio, the mean stress, the mixed mode, and the load sequence on the crack tip residual -stress zone under variable amplitude loadings. Besides, the size and shape of crack tip residual-stress zone are simulated for low/high, high/low block loadings and with/without overloads. Moreover, and according to the findings, a FCG code using the Python script and the extended finite element method (XFEM) Is improved. The developed code processes FCG behavior under variable amplitude loadings using the shape of residual stress distribution near the crack tip. The predicted results show a good agreement in simulating fatigue crack path under variable amplitude loadings with those published in the literature. The originality of this study is to simulate the fatigue crack path of cracked structures under variable amplitude loadings with the compressive residual stress model coupled with the XFEM for mode I and different mixed mode.