Designing a bioinspired scaly textured surface for improving the tribological behaviors of starved lubrication

Scale/scaly structures are commonly seen in living nature, such as loach and pangolin, and they generally play an important role in reducing friction between biosurfaces and their contacted solid/water. Hence, inspired by scale structures in biology, we propose a design of surface texturing with 3D delicate scaly structures to improve the tribological behaviors of mechanical friction interfaces under starved lubrication. Micro 3D metal printing technology was employed to fabricate the scaly textured surface. Experimental tests were performed and the results demonstrated the favorable effect of such bionic texturing on reducing friction coefficient and wear. Furthermore, corresponding FEM simulations and high-speed camera observation confirmed the amplification effect of secondary lubrication and the pre-lubrication effect as the dominating mechanisms. • A bioinspired 3D scaly surface texturing was designed and fabricated. • Friction coefficient reduction effect of the 3D textures was demonstrated. • Amplification of secondary lubrication and the pre-wetting effect were deduced as the main mechanism.