Low friction properties of graphene films

Graphene has excellent mechanical characteristics and chemical stability, and its use as an ultrathin solid lubrication material is especially promising. In recent years, encouraging results have been reported on the friction characteristics of graphene, not only on the microscale or nanoscale but also on the macroscale. As the macroscale friction properties of graphene vary greatly depending on the friction conditions, it is important to find the optimum conditions to obtain better friction properties and elucidate the friction mechanism. In this study, we succeeded in the onset of ultralow friction phenomenon of the graphene on the macro-load scale under air and controlled environmental conditions, and clarified the friction mechanism. Furthermore, for application to the industry, we developed a direct synthesis method of graphene onto a target substrate, and examined the uniformity of ion implantation for the application to the three-dimensional machine elements.