滚动轴承内圈不同曲率初始次表面裂纹的扩展仿真研究

Simulation on propagation of initial subsurface cracks with different curvatures in inner ring of rolling bearing

滚动轴承内圈次表面裂纹的动态扩展将影响轴承工作的稳定性,继而影响轴承的剩余使用寿命。针对这一问题,研究了滚动轴承内圈上不同曲率的初始次表面裂纹对应力分布和裂纹扩展的影响规律。首先,基于扩展有限元方法,构建了承受径向载荷的圆柱滚子轴承有限元模型;然后,基于滚动轴承次表面裂纹的形态特征,模拟了滚道次表面不同曲率的初始裂纹在径向载荷下的动态扩展过程;最后,基于模拟结果,在相同工况下,分析并讨论了次表面裂纹尖端应力随裂纹曲率的变化规律,以及裂纹尖端应力对裂纹扩展的影响。研究结果表明:在径向载荷作用下,次表面裂纹尖端出现应力集中现象;裂纹的扩展主要受水平方向应力(S_(11))的影响;相同工况下,0.25 mm^(-1)~1.67 mm^(-1)曲率范围内的次表面裂纹,曲率较大的裂纹两端的应力较小;次表面裂纹的曲率越大,裂纹的扩展长度和角度均越小;通过比较相同径向载荷下不同曲率次表面裂纹的扩展长度、扩展角度等,发现曲率较大的次表面裂纹对轴承的损伤程度以及寿命的影响较小。这些研究结果可以为更好地理解和预防轴承损伤提供理论依据和参考。

The dynamic propagation of subsurface cracks on the inner ring of rolling bearings can affect the stability of bearing operation,thereby affect the remaining service life.To address this issue,the influence laws of initial subsurface cracks with different curvatures on the stress distribution and crack propagation were investigated for the inner ring of rolling bearings.Firstly,based on the extended finite element method,a model of a cylindrical roller bearing subjected to radial load was constructed.Then,based on the morphological characteristics of the subsurface cracks of the rolling bearing,the dynamic propagation process of the initial cracks with different curvatures on the subsurface of the inner raceway was simulated.Finally,based on the simulation results,the variation of the subsurface crack tip stress with the crack curvature and the influence of the crack tip stress on the crack propagation were analyzed and discussed under the same working conditions.The research results show that stress concentration occurs at the tip of subsurface crack under radial load.The crack propagation is mainly affected by the horizontal stress(S_(11)).Under the same working conditions,the subsurface cracks in the curvature range of 0.25 mm~(-1)~1.67 mm~(-1),the crack ends stress of larger curvature is smaller.The larger the curvature of the subsurface crack is,the smaller the crack propagation length and angle are.By comparing the propagation length and propagation angle of subsurface cracks,it is found that the subsurface cracks with larger curvature have less influence on the damage degree and life of the bearing.These results provide a theoretical basis and reference for better understanding and preventing bearing damage.