润湿性梯度表面微液滴群迁移回填与滚动轴承定量润滑状态调控

定量润滑已成为高速轴承主要润滑方式。高速下润滑剂的飞散和低附着性导致其在固体表面离散化分布，不利于润滑剂迁移回填，使得轴承等关键零部件的服役性能不佳。本课题针对润滑剂在固体壁面上的离散滴状分布，拟构筑润湿性梯度表面诱导微液滴群迁移回填，以达到润滑剂高效利用与润滑状态调控的目的。内容包括：1) 设计制备可诱导微液滴群自发迁移合并与回填的润滑性梯度表面；2) 荧光测量滚道远端离散液滴群定向迁移合并行为、近滚道区润滑油回填行为及主油池分布形态；3) 定量供油条件下液滴群迁移回填效应的实验研究；4) 定量供油条件下润滑剂回填及润滑油膜建立的理论分析；5) 建立润滑状态与液滴分布特征、表面特性和主油池形态的关联性。本项目将润滑研究重点转向接触区外围液滴群回填利用与调控，并建立润湿性梯度表面设计准则。该项研究可探索出定量润滑条件下控制轴承润滑状态的新策略，为提升高速滚动轴承润滑技术提供可行性方案。

The technique with fixed oil amount feeding has primarily used in high speed bearings lubrication. However, at high speeds, the lubricant will discretely distribute on bearing surfaces due to splash and poor adhesion. This distribution pattern is negative for lubricant replenishment, resulting in low performance of bearings and mechanical parts. Therefore, considering the distributions of droplet-shape lubricant, it is attempted to build a wettability gradient surface to induce the lubricant motion and replenishment. The purposes of this proposal are to enhance the utilization of lubricant and to regulate the lubrication of rolling bearings. This proposal includes: 1) design and preparation wettability gradient surfaces that can be used to induce the droplet group motion, coalescence and replenishment; and 2) measurement of droplet motion and coalescence, lubricant replenishment close to the contacts and the pattern of main oil reservoir with fluorescence technique; and 3) experimental studies on the effects of the replenishments of droplet groups; and 4) theoretical analysis of lubricant replenishment and lubricating film formation; and 5) establishment of the relationship between lubrication state and lubricant distributions and patterns of main oil reservoir. This study focuses on the utilization of droplet groups that locate at two sides rolling track. And the design criterion for different wettability gradient surfaces will be formed. This study may provide a new strategy to control bearing lubrication and a reasonable plan to enhance lubrication technique for high speed rolling bearings.