Multi-parameter fatigue life prediction model considering fatigue limit and average stress effect

In the prediction of fatigue life, traditional single stress amplitude models frequently fail to sufficiently account for multiple influencing factors under complex loading conditions, especially the effects of fatigue limits and mean stress. To enhance the accuracy of fatigue life prediction, this study introduces an improved multi-parameter fatigue life prediction model. Building upon the classical stress-life (S-N) relationship, the proposed model integrates the effects of fatigue limits, stress amplitude, and mean stress. To validate the efficacy of the proposed model, experimental data from six types of alloys and steels were employed. The results demonstrate that the proposed model achieves high prediction accuracy under varying temperature and stress ratio conditions. Compared to traditional SWT and Lv models, the proposed model more effectively fits diverse types of fatigue experimental data, thereby significantly enhancing the accuracy of fatigue life prediction.