Прогнозування довговічності сплавів за непропорційного навантаження

This work addresses the problem of predicting material fatigue life under conditions of nonproportional loading. A modification of the Fatemi-Socie model is proposed, which includes a parameter that accounts for the influence of the rotation of principal stress axes and additional hardening effects. The model is based on experimental results for axial loading, torsion, and circular trajectories. A comparative analysis of prediction accuracy is conducted in comparison with classical critical plane models. As a result, it was established that directly accounting for the parameters of nonproportional loading sensitivity and the shape of the trajectory significantly improves the model's correlation with experimental data. The proposed criterion for non-proportional loading demonstrates better fatigue life prediction results for both low cycle and high cycle fatigue compared to the considered critical plane models.