Wedge-shaped lyophilic pattern on superlyophobic surface for unidirectional liquid guidance and lubrication enhancement

Effective maintenance of lubricants within the frictional interface is of great importance for the long-life operation of mechanical components. This paper proposes a wedge-shaped lyophilic groove with secondary structures on superlyophobic surfaces to achieve unidirectional guidance of liquid droplets. The experimental studies demonstrate its rapid and long-distance unidirectional self-driven spreading on water and oil droplets. Then, wedge-shaped lyophilic grooves were designed on non-contact area of friction pair to guide lubricant. Relatively lower and more stable friction coefficients were achieved. Further analysis reveals that wedge-shaped grooves restrict the drainage of liquid lubricants. The results of bearing experiments show that designing lyophilic wedge-shaped grooves in the non-contact area of the rolling bearing can effectively reduce the temperature rise of the outer ring.