This study investigates multiaxial fatigue behavior of ductile construction steel S355 and cast iron EN-GJS-500-14. Fatigue lives and crack initiation orientations are measured. Three critical plane models are evaluated for predicting fatigue life and crack initiation angles. While all models achieve decent accuracy in predicting fatigue life, crack initiation angle predictions are less satisfactory. Weak correlation is observed between the quality of fatigue life and crack orientation prediction, particularly for the Smith–Watson–Topper (SWT) and Fatemi-Socie (FS) models. The SWT model performs better in predicting fatigue life and crack angles for cast iron, while the FS model shows higher accuracy for S355. The short-crack model (SC) provides the best overall fatigue life prediction but crack orientation estimation is not superior.

中文翻译：

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钢和铸铁的多轴疲劳行为和裂纹方向预测

本研究研究了延性结构钢 S355 和铸铁 EN-GJS-500-14 的多轴疲劳行为。测量疲劳寿命和裂纹萌生方向。评估三个临界平面模型以预测疲劳寿命和裂纹萌生角度。虽然所有模型在预测疲劳寿命方面都达到了不错的精度，但裂纹萌生角度预测却不太令人满意。疲劳寿命质量和裂纹方向预测之间的相关性较弱，特别是对于 Smith-Watson-Topper (SWT) 和 Fatemi-Socie (FS) 模型。 SWT 模型在预测铸铁的疲劳寿命和裂纹角度方面表现更好，而 FS 模型对 S355 的预测精度更高。短裂纹模型 (SC) 提供了最佳的整体疲劳寿命预测，但裂纹方向估计并不优越。