液晶和碳纳米管协同增强微纳米间隙润滑性能的机理研究

Lubrication plays a important role in reducing friction and preventing wear. High-performance lubricantion design is the key to ensure the service life and running accuracy of the mobile components. The relationship between the molecular structure of lubricant confined in the micro-gap and its rheological behaviors, and lubrication behaviors is always the hot topic in the lubrication field. From boundary lubrication to elastohydrodynamic lubrication, the influence of molecular arrangment and rheological behaviors of lubricants on lubrication performance still need to be further studied. In this project, the liquid crystals and carbon nanotubes are used as the research objects. Based on the low friction coefficient of liquid crystal, the high load bearing ability of carbon nanotubes, and their synergetic enhancement orientation behaviors, to realize the high-performance lubricantion. Establish a theory model to describe the relationship between microscopic molecular arrangement of liquid crystal and carbon nanotubes, and its rheological behaviors. The lubrication performance of liquid crystals and carbon nanotubes confined in the micro/nanoscale gap and their lubrication mechnism are studied. Then, the influence rules of molecular arrangement and rheological behavior on their lubrication performance are revealed. The research can provide supports for the molecular structure design of high-performance lubricant, enrich the theory and practice of micro/nano-scale lubrication, and has important scientific research and engineering application value.

润滑是降低摩擦、减少和避免磨损的必要手段，高性能的润滑设计是保证装备活动构件服役寿命、运行精度的关键。微间隙润滑剂分子排列与其流变行为和润滑行为的关系一直是润滑领域重要研究课题。在从边界润滑到弹流润滑的状态改变过程中，润滑剂分子排列取向和流变行为对其润滑性能影响规律的研究以及定量描述仍然有待深入。本课题将采用具有优良摩擦学性能的液晶和碳纳米管作为润滑剂，基于液晶的低摩擦特性、碳纳米管的高承载和减磨性能以及液晶分子和碳纳米管的协同取向行为实现微纳米间隙高性能润滑的设计。建立液晶分子和碳纳米管微观取向排列结构与流变行为的理论模型；揭示微纳米间隙液晶和碳纳米管协同增强微纳米间隙润滑性能的机理，构建润滑剂分子排列取向和流变行为影响其微纳米间隙润滑性能的机制。本课题的研究可为高性能润滑剂分子的结构设计提供支持，丰富微纳受限尺度润滑理论与实践，具有重要的科学研究和工程应用价值。

润滑是降低摩擦、减少和避免磨损的必要手段，高性能的润滑设计是保证装备活动构件服役寿命、运行精度的关键。而微间隙润滑剂分子排列与其润滑行为密切相关。项目围绕液晶和碳纳米管协同增强微间隙润滑性能，采用试验和分子动力学模拟相结合的方法开展相关研究。探索了碳纳米管、摩擦剪切、表面微沟槽诱导分子取向行为，有效改善润滑性能的规律和机制，研究了液晶和碳纳米管单独或协同作为润滑油添加剂对基础油润滑性能的影响规律和机理。项目研究结果表明，摩擦剪切作用可以有效地促进液晶分子沿着剪切方向取向，且摩擦改善液晶取向有序度的作用强于CNTs；表面微织构可以有效诱导液晶分子沿着沟槽方向取向，在剪切运动、碳纳米管和表面微沟槽三者的协同作用下可有效促进液晶有序排列，进而提高了其减摩性能；阐明了液晶和碳纳米管单独或协同增强润滑性能机理，获得了相应工况条件下最优化液晶和碳纳米管添加剂的配比。项目研究为高性能润滑剂的设计提供了理论支撑和实验指导。