轴承滚道疲劳损伤机理研究

发布时间：2018-03-03 07:09

本文选题：轴承滚道　切入点：疲劳损伤　出处：《武汉理工大学》2014年博士论文　论文类型：学位论文

【摘要】：轴承是重大装备的基础零部件，，直接影响到装备的服役性能和寿命。随着科学技术的高速发展，轴承的使用条件和运行环境越来越复杂，这对轴承的材料、结构和性能提出了更高的要求。一些重大装备如飞机、高速列车、机床和风力发电机等需在高速、重载、高温等苛刻的服役条件下工作，对轴承的服役性能特别是抗疲劳性能提出了更高的要求。为了提高轴承的抗疲劳性能，迫切需要开展轴承滚道疲劳损伤机理方面的研究。为此，本文采用理论分析、有限元数值模拟和实验研究方法，对轴承滚道疲劳裂纹萌生和扩展机理以及轴承套圈疲劳寿命预测进行了系统的研究，主要内容和研究成果如下：通过理论分析和有限元数值模拟，确定了一种准确预测服役条件下轴承套圈疲劳寿命的方法，研究了轴承载荷、套圈壁厚和滚道沟曲率半径等参数对轴承套圈疲劳寿命的影响，为合理的选取轴承的设计参数提供了理论依据。运用线弹性断裂理论、疲劳裂纹扩展判定准则和最大主应力准则，结合有限元数值模拟和实验分析，研究了材料缺陷对轴承滚道接触疲劳失效机理的影响规律，分析了疲劳裂纹的主要扩展模式、生长速率和生长方向，揭示了材料缺陷对轴承滚道疲劳损伤的影响机制，为预测轴承套圈的疲劳失效行为提供了理论依据。运用几何学、力学和疲劳损伤理论建立了存在表面裂纹的圆锥滚子轴承模型，研究了周向和母线方向的表面牵引对滚道表面裂纹生长的影响，揭示了裂纹深度、生长方向和裂纹二次生长角度对疲劳剥离形成的影响规律，为预测轴承滚道的疲劳剥离程度和剥离路径提供了理论依据。运用材料学和力学理论，结合轴承疲劳实验和有限元数值模拟，分析了轴承滚道疲劳剥离区域的微观形貌，研究了滚道轴向和周向截面的裂纹萌生和扩展机理，分析了滚道截面显微硬度的变化规律，揭示了夹杂物、碳化物、空位等材料缺陷对裂纹形核和萌生的作用机制，比较分析了轴承滚道次表面和心部位置的微观组织演化规律，揭示了微观组织状态与轴承套圈疲劳寿命之间的相互作用关系。
[Abstract]:Bearing is the basic part of heavy equipment, which directly affects the service performance and service life of the equipment. With the rapid development of science and technology, the operating conditions and operating environment of the bearing are becoming more and more complicated. Higher requirements for structure and performance. Some major equipment, such as aircraft, high-speed trains, machine tools and wind turbines, are required to operate under harsh service conditions such as high speed, heavy load, high temperature, etc. In order to improve the fatigue resistance of bearing, it is urgent to study the fatigue damage mechanism of bearing raceway. In order to improve the fatigue performance of bearing, the research on fatigue damage mechanism of bearing raceway is urgently needed. The fatigue crack initiation and propagation mechanism of bearing raceway and the fatigue life prediction of bearing ring are systematically studied by finite element numerical simulation and experimental method. The main contents and results are as follows:. Through theoretical analysis and finite element numerical simulation, a method of accurately predicting the fatigue life of bearing ring under service condition is established, and the bearing load is studied. The influence of ring wall thickness and raceway curvature radius on the fatigue life of bearing ring provides a theoretical basis for the reasonable selection of bearing design parameters. Based on linear elastic fracture theory, fatigue crack growth criterion and maximum principal stress criterion, combined with finite element numerical simulation and experimental analysis, the influence of material defects on the failure mechanism of bearing raceway contact fatigue is studied. The main propagation mode, growth rate and growth direction of fatigue crack are analyzed. The influence mechanism of material defects on fatigue damage of bearing raceway is revealed, which provides a theoretical basis for predicting the fatigue failure behavior of bearing ring. Based on geometry, mechanics and fatigue damage theory, the model of tapered roller bearing with surface crack is established. The influence of surface traction in circumferential and busbar direction on the growth of surface crack in raceway is studied, and the crack depth is revealed. The influence of growth direction and secondary growth angle of crack on the formation of fatigue peeling provides a theoretical basis for predicting the degree and path of fatigue peeling of bearing raceway. Based on the theory of materials and mechanics, combined with bearing fatigue experiment and finite element numerical simulation, the micro-morphology of fatigue peeling region of bearing raceway was analyzed, and the crack initiation and propagation mechanism of raceway axial and circumferential section was studied. The variation of microhardness of raceway cross section is analyzed, and the mechanism of inclusions, carbides and vacancies on crack nucleation and initiation is revealed. The microstructure evolution law of the subsurface and center of the bearing raceway is compared and analyzed. The interaction between the microstructure state and the fatigue life of bearing ring is revealed.
【学位授予单位】：武汉理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TH133.3

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