weight and corrosion-resistant material widely used in marine and structural applications. Fatigue failure in such components often initiates at stress concentrators such as holes and preexisting cracks, especially under cyclic multiaxial loading. To quantify the combined influence of geometric and loading parameters, experimental tests and numerical simulations were performed on rectangular sheets containing holes, subjected to mixed-mode I/II cyclic loading. The effects of hole size, hole–crack distance, loading angle, and load ratio on crack trajectories, stress intensity factors (SIFs), and fatigue life were analysed. The numerical model was implemented using the Extended Finite Element Method (XFEM) in ABAQUS, with mixed-mode SIFs evaluated via Tanaka’s model, and a Taguchi design was used to assess the relative importance of the parameters. The results show that the load ratio has the most significant influence on SIF levels and crack path deviation, while the loading angle and hole position are the most effective parameters for promoting crack arrest at the hole. Increasing the loading angle, hole–crack distance, and load ratio leads to longer fatigue lives, whereas increasing the hole diameter reduces fatigue life. Overall, the study demonstrates that strategically tailoring hole geometry and loading conditions can either enhance or degrade fatigue performance, and provides valuable guidance for the design and optimisation of structural components containing holes under mixed-mode cyclic loading.

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