Chapetti Mirco Daniel
Laboratory of Experimental Mechanics, INTEMA, National University of Mar del Plata-CONICET, Av. Colón 10.850, Mar del Plata B7600, Argentina.
Materials (Basel). 2024 Sep 21;17(18):4632. doi: 10.3390/ma17184632.
The issues of the high-cycle fatigue resistance of notches and the role of non-propagating short cracks in defining the fatigue notch sensitivity and fatigue limit of the configuration are addressed. A fracture mechanics approach is employed to determine the threshold configuration that defines the associated fatigue limit. The influence of notch sharpness, notch size, intrinsic fatigue limit, microstructural dimensions, and the threshold for crack propagation is examined. A simple expression is proposed to estimate the maximum fatigue notch factor, , which incorporates the influence of these non-propagating cracks. The fatigue limits for both blunt and sharp elliptical notches are analyzed and predicted based on experimental results reported in the literature. Additionally, shallow notches or small defects are analyzed, where it is found that the same hypothesis may not be applicable.
本文探讨了缺口的高周疲劳抗力问题，以及非扩展短裂纹在确定该结构的疲劳缺口敏感性和疲劳极限方面的作用。采用断裂力学方法来确定定义相关疲劳极限的临界结构。研究了缺口锐度、缺口尺寸、固有疲劳极限、微观结构尺寸以及裂纹扩展阈值的影响。提出了一个简单的表达式来估算最大疲劳缺口系数，该系数考虑了这些非扩展裂纹的影响。基于文献报道的实验结果，分析并预测了钝椭圆缺口和尖锐椭圆缺口的疲劳极限。此外，还分析了浅缺口或小缺陷，发现相同的假设可能不适用。
