Insights into friction behavior of textured amorphous carbon and lubricant composite system: Dependence on the lubricant viscosity and textured shape

Abstract

Combining textured amorphous carbon (a-C) film with lubricant achieves ultra-low friction to improve the mechanical component's service life. However, the coupling influence of lubricant viscosity and textured shape on friction behavior and interfacial transformation are still unclear. In this work, the evolution of friction performance with Poly-alpha-olefin viscosities and its dependence on textured shapes were investigated by reactive molecular dynamics simulation. Results reveal that as the textured shape is fixed, increasing the lubricant viscosity causes friction coefficient to decline first and then increase, due to the hydrodynamic lubrication and regional aggregation of lubricant. While under same lubricant condition, rectangular textured systems exhibit lower friction coefficient than circular textured ones, attributing to the formation of stable lubricant film without serious aggregation.