圆柱滚子轴承打滑损伤机理研究

Rotating machinery is developing towards the directions of high speed and high power ratio. Unfortunately, the cylindrical roller bearing, as the key part of the rotating machinery, its reliability has been severely undermined by skidding damage. Under the guidance of the modern tribological theory, the project declaration aims at processing systematically experimental studies on the skidding damage of cylindrical roller bearing, which is the common problem in the field of rotating machinery. With the help of new experimental device for testing the skidding process of cylindrical roller bearing, the skidding process is monitored in real time and the skidding damage scene is recalled accurately. Moreover, under the premise of controlling vibration frequency, the influences of many parameters on skidding damage of bearings with different materials will be studied carefully in this project, and the parameters include shaft speed, radical load, bearing temperature, the lubricating oil temperature and so on. Based on the establishment of the skidding running behavior curve, and combined with the microscopic analysis of the skidding damage, the influences of the test parameters and materials on the rules of cylindrical roller bearing skidding damage and coupling mechanism will be studied in detail. Eventually, the mechanism of the skidding damage of cylindrical roller bearing will be revealed in this project. Besides the prominent scientific value in exploring the unknown domain and improving the existing rolling bearing tribological theory, the project also has significant engineering application background. It has great reference value for the domains where skidding damage protection is necessary, such as aeroengine, wind turbine, NC machine tool and other large rotating machinery.

随着旋转机械朝着高转速、高功重比方向发展，圆柱滚子轴承作为旋转机械的关键部件因打滑损伤已严重制约其可靠性。本项目针对旋转机械的关键共性问题——圆柱滚子轴承打滑损伤，提出运用现代摩擦学理论，系统地对圆柱滚子轴承打滑损伤进行试验研究。通过建立新型圆柱滚子轴承打滑试验装置，实现打滑的实时监控和再现打滑损伤。针对不同材质的轴承，在控制振动频率的前提下，进行轴转速、径向载荷、轴承温度和润滑油温度等不同参数的轴承打滑损伤研究。在建立打滑运行行为曲线的基础上，结合打滑损伤微观分析，研究不同试验参数和材料性质对圆柱滚子轴承打滑损伤的影响规律及耦合机制，最终揭示圆柱滚子轴承打滑损伤机理。本研究不仅具有探索未知领域的科学价值，深化滚动轴承摩擦学基础理论，而且有重要工程应用背景，对航空发动机、风力发电机、数控机床等大型旋转机械广泛存在的圆柱滚子轴承打滑损伤防护具有重要参考价值。

随着旋转机械朝着高转速、高功重（推重）比方向发展，圆柱滚子轴承DN值越来越大，高DN值使得圆柱滚子轴承失效除了正常的疲劳破坏外，更多情况是因打滑引起的摩擦磨损。打滑会造成轴承磨损、擦伤、裂纹、剥落、塑性变形等损伤，最终导致轴承早期失效，严重影响轴承的寿命和可靠性。本项目针对旋转机械的关键共性问题——圆柱滚子轴承打滑损伤，在滚动轴承试验机上，在不同径向载荷、轴转速、进油量等参数下开展圆柱滚子轴承打滑损伤试验。采用光学显微镜、扫描电子显微镜、电子能谱仪、拉曼光谱、X射线光电能谱和表面形貌仪等微观分析手段，结合打滑动力学特性分析，系统研究圆柱滚子轴承打滑运行行为和损伤机理。主要研究成果包括：1. 圆柱滚子轴承发生打滑损伤瞬间摩擦扭矩、振动加速度及其温度的同步突增；2. 摩擦扭矩随转速的增加呈现先增加后略有减小并逐渐趋于稳定的趋势，摩擦扭矩随径向载荷的增加呈先快速增加后增幅减缓的趋势；振动加速度随转速的增加呈逐步递增趋势，且转速较高时，增加较快；轴承温度随转速的增加及进油量的减小呈逐步递增趋势；转速加速度越大，摩擦扭矩、振动加速度增加越快，且摩擦扭矩极限值越大，转速稳定后，摩擦扭矩和振动加速度在不同加速度下相差不大。3. 打滑损伤瞬间所形成的巨大切应力使得轴承在次表面缺陷处萌生裂纹，随后在循环应力及热的作用下，裂纹沿纵、横向扩展，直至裂纹与表面闭合而形成剥落。圆柱滚子轴承打滑损伤机制涉及氧化磨损、磨粒磨损及剥层。此外，揭示了打滑烧伤的动力学行为和损伤机制。本研究不仅有助于丰富滚动轴承摩擦学基础理论，而且对航空发动机、风力发电机、数控机床等大型旋转机械广泛存在的圆柱滚子轴承打滑损伤防护具有重要的工程指导意义。