沙尘环境下轴承橡胶密封颗粒诱导磨损失效机理与防护研究

Rubber seals are indispensable components for high-speed rail bearing, because of it’s an important barrier to prevent lubricant leakage and resist pollutant invasion. However, as high-speed rail often served in harsh environments, such as the sandstorm, road dust or even haze, it is difficult to avoid all kinds of fine particles into the high-speed rail bearings that exposed to the car body. Which becomes a prominent obstacle problem that restricts the long service life and high reliability of high-speed rail bearings, due to abrasive wear failure of rubber seals under sand-dust environment. But until now, there are still no common understanding of the effect of different shapes and properties particles on the wear failure of rubber seals and related mechanisms, currently available guidance is very far from the requirement in the design and application of bearing seal. Therefore, this project proposes a systematic study on failure mechanism and protection of particle induced wear in bearing rubber seal under sand and dust condition. The purpose of this project is to study the effect of sandstorm, road dust, especially haze on the wear failure of rubber seal, and to clarify the accelerated erosion mechanism induced by different shapes and properties particles, the protection countermeasure will be proposed to reduce the wear of the rubber seal and improve the service life of the bearing, and the optimizing design method of rubber seals in the high-speed rail bearing base on tribology will be established to prevent leakage and anti-dust. This research will not only have significant theoretical value for enriching the theoretical system of rubber tribology, but also contribute to improvement the service life of high-speed rail bearings and then have great social benefits and application value.

橡胶密封作为高铁轴承的重要组成部分，是防止润滑剂外泄、抵御污染物入侵的重要屏障。然而，高铁常服役于风沙、路面扬尘或雾霾等恶劣环境，很难避免各类微细颗粒物侵入暴露于车体外的高铁轴承内。沙尘环境下橡胶密封的磨粒磨损失效已成为制约高铁轴承长寿命、高可靠运行的突出问题，亟待解决。目前，国内外针对不同形性颗粒物对橡胶密封磨损失效的影响机制及作用机理尚无统一认识，仍难以为轴承密封设计与应用提供良好指导。为此，本项目提出系统开展沙尘环境下轴承橡胶密封颗粒诱导磨损失效机理与防护对策研究，旨在探明风沙、扬尘尤其是雾霾对橡胶密封磨损失效的影响，阐释不同形性颗粒的磨损加速破坏机制，提出减缓密封件磨损、提高轴承服役寿命的防护对策，从摩擦学角度建立高铁轴承防尘御漏的密封设计方法。相关研究不仅对丰富发展橡胶摩擦学理论体系具有重要的理论价值，而且有助于提高高铁轴承的服役寿命，具有重大的社会效益和应用价值。

橡胶密封作为高铁轴承的重要组成部分，是防止润滑剂外泄、抵御污染物入侵的重要屏障。然而，高铁常服役于风沙、路面扬尘或雾霾等恶劣环境，很难避免各类微细颗粒物侵入暴露于车体外的高铁轴承内。沙尘环境下橡胶密封的磨粒磨损失效已成为制约高铁轴承长寿命、高可靠运行的突出问题，亟待解决。目前，国内外针对不同形性颗粒物对橡胶密封磨损失效的影响机制及作用机理尚无统一认识，仍难以为轴承密封设计与应用提供良好指导。本项目完成了干态和水介质环境下颗粒浓度和颗粒尺寸对密封副摩擦学行为的影响，分析了颗粒浓度对密封副磨损失效的作用机制，揭示了颗粒“尺寸效应”下密封副受磨粒磨损作用下破坏机制，发现了“突脊-犁沟-突脊”交替的典型损伤特征且揭示了该损伤形貌的微流道效应。基于上述系统研究，从接触应力、颗粒尺寸角度考虑提出了预防密封副失效的防护措施；探讨了橡胶表面接枝聚合物刷和金属配副表面设计减摩涂层对橡胶摩擦学性能的改善作用，从摩擦学角度建立高铁轴承防尘御漏的密封设计方法。包括：从配副表面减摩抗磨角度出发提出了提高轴承密封服役寿命的防护对策；提出了“防尘罩主动过滤”、“高耐磨涂层主动抗磨”和“微织构主动润滑与捕获颗粒”的多道防护与协同优化措施。以上防护对策可以有效减缓密封件磨损、提高轴承服役寿命。此外，在本项目的资助下，发表学术论文20余篇，其中SCI检索论文11篇、EI检索论文8篇。相关研究成果不仅对丰富发展橡胶摩擦学理论体系具有重要的理论价值，而且有助于提高高铁轴承的服役寿命，具有较为显著的社会效益和应用价值。