Study on influence of micro convex textures on tribological performances of UHMWPE material under the water-lubricated conditions

Abstract

As one important supporting component of the ship propulsion system, the water-lubricated stern tube bearing has profound effects on navigation safety. One the other hand, it is difficult to ensure the adequate lubrication for water-lubricated stern tube bearing under low speed working conditions. In order to mitigate this problem, contemporary bearing systems have been built of Ultra-High Molecular Weight Polyethylene (UHMWPE). However, it is observed that material surface texture features have a significant impact on the lubrication effectiveness. In this research, three types of micro convex textures such as cuboid structure were designed and surfaces of UHMWPE samples were moulded. A series of experimental tests were then carried out in a specially designed tester to investigate the tribological characteristics of different convex texture designs. Comparative analyses were conducted on friction coefficients, wear mass losses and worn surfaces for different convex textures and running conditions. Analysis results showed that there are significant differences in tribological properties of rubbing pairs with different convex textures. The variations of the friction coefficient of convex textured samples are less than the original sample. The wear performance of the convex textured design is superior to that of other convex textures. The convex textured is the most effective design in improving wear properties at a low sliding velocity of 0.063 m/s. This work has established a practical basis for optimal texture design, of water-lubricated material, for reduced wear and improved lubrication performance.