Gao Ruipeng, Liu Mengmeng, Wang Bing, Wang Yiran, Shao Wei
School of Mechanical and Precision Instrument Engineering, Xi'an University of Technology, Xi'an 710048, China.
State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Materials (Basel). 2021 Sep 30;14(19):5720. doi: 10.3390/ma14195720.
Wheel rail rolling contact fatigue is a very common form of damage, which can lead to uneven rail treads, railhead nuclear damage, etc. Therefore, ANSYS software was used to establish a three-dimensional wheel-rail contact model and analyze the effects of several main characteristics, such as the rail crack length and crack propagation angle, on the fatigue crack intensity factor during crack propagation. The main findings were as follows: (1) With the rail crack length increasing, the position where the crack propagated by mode I moved from the inner edge of the wheel-rail contact spot to the outer edge. When the crack propagated to 0.3-0.5 mm, it propagated to the rail surface, causing the rail material to peel or fall off and other damage. (2) When the crack propagation angle was less than 30°, the cracks were mainly mode II cracks. When the angle was between 30 and 70°, the cracks were mode I-II cracks. When the angle was more than 70°, the cracks were mainly mode I cracks. When the crack propagation angle was 60°, the equivalent stress intensity factor reached the maximum, and the rail cracks propagated the fastest.
轮轨滚动接触疲劳是一种非常常见的损伤形式，它会导致钢轨踏面不均匀、轨头核伤等。因此，利用ANSYS软件建立了三维轮轨接触模型，并分析了钢轨裂纹长度和裂纹扩展角度等几个主要特征对裂纹扩展过程中疲劳裂纹强度因子的影响。主要研究结果如下：(1)随着钢轨裂纹长度的增加，Ⅰ型裂纹扩展的位置从轮轨接触斑内边缘移至外边缘。当裂纹扩展到0.3-0.5mm时，扩展至钢轨表面，导致钢轨材料剥落或脱落等损伤。(2)当裂纹扩展角度小于30°时，裂纹主要为Ⅱ型裂纹。当角度在30°至70°之间时，裂纹为Ⅰ-Ⅱ型裂纹。当角度大于70°时，裂纹主要为Ⅰ型裂纹。当裂纹扩展角度为60°时，等效应力强度因子达到最大值，钢轨裂纹扩展最快。
