Abstract
The interfacial friction performances of graphene covered and hydrogen-terminated diamond surfaces were investigated comparatively by first-principles calculations within density functional theory (DFT). Both systems exhibit similar excellent lubricating effects under small load, but the graphene covered interface presents small friction than that of hydrogenated system for the larger load. The calculated interfacial friction between two sheets of graphene covered diamond surface increases slowly than that of hydrogenated system in a wide range of pressure scale, and the friction difference between the two systems increases with increasing external pressure, indicating that graphene has flexible lubricating properties with high load-carrying capacity. This behavior can be attributed to the large interlayer space and a more uniform interlayer charge distribution of graphene covered diamond interface. Our investigations suggest that graphene is a promising candidate as solid lubricate used in diamond film, and are helpful for the understanding of interfacial friction properties of diamond film.
Highlights
Diamond coatings, from diamond single crystal (DSC) film to amorphous diamond-like carbon (DLC) film, have attracted great interest in both industrial application and scientific research fields due to its low friction, high wear resistance properties [1]
We found that graphene coating has flexible lubricating properties with high load-carrying capacity when used in the diamond film system
Our results show that diamond film substrate has little influence on the interfacial friction properties of bilayer graphene, which indicates that the graphene can provide an effective shielding to the diamond surface
Summary
From diamond single crystal (DSC) film to amorphous diamond-like carbon (DLC) film, have attracted great interest in both industrial application and scientific research fields due to its low friction, high wear resistance properties [1]. Sliding-induced graphitization [2,3,4,5] and passivation of dangling bond [6,7,8] are two widely accepted mechanisms for the excellent tribological behaviors of diamond films. Several researchers found that graphite-like carbon film formed by sliding-induced graphitization is the main reason for the low friction and wear of DLC films [3,4,5]. Other experimental and theoretical studies supported the view that passivation of unsaturated carbon at the sliding interface is the main mechanism for the excellent friction properties [6,7,8]. As the complexity of the interface and the sensitivity of friction to external factors, such as pressure, humidity and sliding velocity, it is difficult to evaluate which mechanism plays a determining role in applications
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
