Influence of characteristic parameters on the tribological properties of vein-bionic textured cylindrical roller thrust bearings

In this research, three types of vein-bionic texture patterns inspired by five kinds of leaves (Forsythia, Clausena lansium, Ash, Pipal, and Apricot) were designed and fabricated on the raceways of the shaft washers of cylindrical roller thrust bearings (CRTBs) through a fiber laser marking system. A vertical universal wear test rig was used to obtain the coefficient of friction (COF) of bearings under starved lubrication, with a customized tribo-pair. The wear losses of the shaft washers and the worn surfaces were characterized. The influence of different veins (chief, primary, secondary) and vein-structure characteristics (pattern symmetry, number of veins) on the tribological behavior of vein-bionic textured CRTBs is investigated and discussed. The results show that the original vein-bionic (V) pattern inspired by the Ash has the best friction-reducing performance, while the texture with the no-chief vein (NC) obtained by Clausena lansium has the best wear resistance. The chief vein mainly contributes to the low friction by enhancing the secondary lubrication effect and facilitating the formation of a protective nylon film. A reasonable mechanism for improving the tribological properties of resulting textures is proposed.