楔形亲油轨道-超疏水复合图案化表面液滴引导及润滑增效研究

目的 实现液滴及润滑油在超疏水表面定向引导，并将其运用于机械摩擦副，改善摩擦润滑性能。方法 提出一种简单的超疏水高疏油涂层制备方法，即在硅烷耦合剂作用下利用1H,1H,2H,2H-全氟癸基三乙氧基硅烷（FAS-17）改性气相纳米二氧化硅，经交联固化处理后制得具有超疏水高疏油特性的涂层。通过FT-IR分析涂层成分、SEM观测涂层形貌，验证了涂层制备方案的有效性。通过纳秒激光在疏油涂层上加工亲油楔形图案化表面，进行表面流体引导实验。通过开展球-盘标准摩擦实验和滚动轴承温升实验来验证楔形亲油图案化表面流体引导，用于实现机械摩擦润滑增效的有效性。结果 通过对涂层表面进行成分分析，验证了C-F键长链在二氧化硅粒子表面上的成功枝接。通过对涂层表面进行形貌观测，验证了表面微纳米粗糙结构的成功构建。所制备得到涂层表面去离子水、PAO4、石蜡油、白油、PAO6、齿轮油接触角分别为157°、142°、143°、144°、136°、145°。相比之下，普通铝板表面去离子水、PAO4、石蜡油、白油、PAO6、齿轮油接触角分别为46°、16°、17°、20°、15°、24°，涂层具有优异的超疏水高疏油特性。通过...

Wedge-shaped Oleophilic Track-superhydrophobic Composite Patterned Surface for Droplet Guidance and Lubrication Synergy

To realize the directional guidance of droplets and lubricating oil on the superhydrophobic surface and apply it to mechanical friction pairs to improve the friction and lubrication performance, a simple and efficient method was used to prepare the superhydrophobic and highly oleophobic coating and wedge-shaped oleophilic patterns to realize the directional guidance of droplets on patterned surfaces. Gas-phase nano-silica, silane coupling agent and 1H,1H,2H,2H-perfluorodecyltriethoxysilane were added to absolute ethanol respectively. Under the action of silane coupling agent, 1H,1H,2H,2H-perfluorodecyltriethoxysilane was used to modify fumed nano-silica. Then epoxy resin and curing agent were added to prepare coating solution with superhydrophobic and high oleophobic characteristics. The composition of the prepared coating was analyzed by FT-IR. It was verified that the oleophobic C-F bond long chain was successfully grafted on the surface of silica particles. A scanning electron microscope (SEM) was used to observe the morphology of the coating, which proved the successful construction of micro-nano rough structure on the surface. The contact angles of 8 mL different droplets on the coating surface were measured by a contact angle measuring instrument. The contact angles of deionized water, PAO4, paraffin oil, white oil, PAO6 and gear oil on the coating surface were 157°, 142°, 143°, 144°, 136° and 145°. In contrast, the contact angles of deionized water, PAO4, paraffin oil, white oil, PAO6 and gear oil on the surface of the ordinary aluminum plate were 46°, 16°, 17°, 20°, 15° and 24° respectively, which proved that the coating had excellent superhydrophobic and high oleophobic properties. Aiming at the abrasion resistance of superhydrophobic coating, the abrasive paper abrasion experiment was carried out. After 50 cycles of experiments, the contact angle of deionized water decreased from 157° to 152°, and the contact angle of gear oil decreased from 145° to 134.6°, which proved that the coating had certain abrasion resistance. Finally, a nanosecond laser system was used to remove part of the superhydrophobic coating to form a wedge-shaped oleophilic pattern for directional guidance of droplets. Through the unidirectional guidance of liquid droplets experiment, the directional guidance of water droplets and paraffin oil on the wedge-shaped oleophilic patterned surface of the oleophobic coating was realized. The wedge-shaped optimal parameters for droplet guidance were determined. Furthermore, the curve trajectory guidance and anti-gravity guidance of droplets on the wedge-shaped patterned surface were realized. A ball disk friction experiment and a bearing temperature rise experiment were carried out. A wedge-shaped oleophilic pattern was prepared after spraying the coating on the non-contact area of friction pair, and the lubricating oil was directionally guided from the non-contact area of friction pair to the friction contact area. The results showed that the wedge-shaped oleophilic patterned surface could effectively reduce the friction coefficient under different working conditions. Under the condition of low speed and heavy load, the friction coefficient was reduced by 16%, and the temperature rise of bearings with wedge-shaped oleophilic patterned surfaces was obviously lower than that of ordinary bearings. The wedge-shaped oleophilic patterned surface of oleophobic coating surface proposed in this paper realizes directional guidance of lubricating oil and other liquids, and proves its effect of moistening and reducing friction of rolling bearings. It has broad application potential in mechanical friction, lubrication and other fields.