High-Cycle Fatigue Performance Assessment of Mg Alloy Welded Joints Using Machine-Learning-Assisted Modeling
摘要
Fatigue failure is a critical concern for Mg alloy welded joints used in lightweight structural applications. Accurate assessment of fatigue life is essential for ensuring structural reliability and service safety. In this study, machine-learning-assisted models are developed to predict the high-cycle fatigue life of Mg alloy welded joints by incorporating stress state, welding method, and material type as input features. Additional physically motivated features derived from empirical fatigue relations are introduced to enhance model robustness. The predictive performance of five representative machine learning models is systematically compared, and the results show that XGBoost achieves the best overall predictive performance on the present dataset. Furthermore, Shapley Additive exPlanations are employed to quantify the influence of key stress parameters, welding methods, and material characteristics on fatigue life. The results indicate that mean stress and stress range dominate fatigue behavior, while welding process and material type also play important roles. This study provides an effective data-driven framework for fatigue performance assessment of Mg alloy welded joints with practical engineering relevance.