The potential of graphene as a solid lubricant in sliding Ag-based electrical contacts has been investigated. Graphene was easily and quickly deposited by evaporating a few droplets of a commercial graphene solution in air. The addition of graphene reduced the friction coefficient in an Ag/Ag contact with a factor of *10. The lubricating effect was maintained for more than 150,000 cycles in a p...

This study deals with experimental and numerical analysis of the thermal effects slender elastohydrodynamically lubricated (EHL) contacts under high sliding. Thereby, entrainment direction is along major axis contact ellipse. Film thickness measurements were carried out on an optical EHL tribometer a glass disk steel roller. Numerical solutions obtained consideration for non-Newtonian rheology ...

Abstract We investigate the persistence of micro-contacts between two elastic random rough surfaces by means a simple model for quasi-static sliding. Contact clusters are calculated with Boundary Element Method, then repeatedly displaced to study evolution original contact area. While real area remains constant due rejuvenation micro-contacts, progressively erased and replaced new ones. find an...

Different lubrication methods such as oil dip or injection are used in gearboxes to lubricate tribological contacts and dissipate frictional heat. To improve resource energy efficiency, novel needs-based like the drop-on-demand being developed. It includes an ink-jet nozzle driven by a piezo element generate picoliter droplets injected contacts. This study evaluates feasibility of gears. Fricti...

Surface topography can affect the tribological performance in many applications. The influence of surface roughness and topographic orientation on friction wear dry oil lubricated steel vs diamond-like carbon (DLC) coated DLC sliding contacts was investigated. surfaces had a centerline average (Ra) between 0.004 0.11 μm groove 0°, 45° 90° with respect to direction. Tests conducted showed that s...