This paper proposes a notch fatigue life prediction model to account for the effect of geometry and applied stress. A double-slope method was proposed to calculate the critical distance, which was utilized to determine the damage zone of geometrically complex structures. An elastic geometrical feature factor was defined to characterize the stress concentration. Considering the effect of applied stress on low cycle fatigue (LCF) life, a stress factor was proposed. A fatigue life estimation approach was established by introducing the elastic geometrical feature factor, the stress factor and an improved critical distance method. This model was validated by the experimental results of notched specimens with various geometries and loadings. Compared with the existing models, the proposed model provides a better accuracy.

本文提出了一个缺口疲劳寿命预测模型，以考虑几何形状和施加应力的影响。提出了一种双斜率方法来计算临界距离，该方法用于确定几何复杂结构的损伤区域。定义了弹性几何特征因子来表征应力集中。考虑到外加应力对低周疲劳（LCF）寿命的影响，提出了应力因子。通过引入弹性几何特征因子，应力因子和改进的临界距离方法，建立了疲劳寿命估算方法。带有各种几何形状和载荷的缺口试样的实验结果验证了该模型。与现有模型相比，提出的模型具有更好的准确性。