Superlubricating Graphene Films
A system and method for forming graphene on a substrate and an opposed wear member having a DLC coating. The system includes graphene formed by an exfoliation process to dispose solution processed graphene onto a substrate. The system further includes an opposing wear member of DLC disposed on another substrate and a gas atmosphere of an inert gas like N 2 .
1 . A method of forming graphene on a substrate, comprising the steps of:
providing a solution processed graphene; and
disposing the solution processed graphene on the substrate, thereby establishing a low friction wear surface.
2 . The method as defined in claim 1 wherein the graphene of the solution processed graphene is formed by at least one of (a) a chemical exfoliation step, (b) mechanical exfoliation, (c) CVD and disposing the graphene into a liquid.
3 . The method as defined in claim 2 wherein the step of disposing the solution processed graphene comprises spraying the liquid containing the graphene onto the substrate.
4 . The method as defined in claim 1 wherein the substrate is selected from the group of a metal, a transition metal and an insulator.
5 . The method as defined in claim 1 further including the step of providing an opposing wear member against which the graphene on the substrate slides.
6 . The method as defined in claim 5 wherein the opposing wear member comprises DLC.
7 . The method as defined in claim 6 wherein the DLC is a hydrogenated form of DLC.
8 . The method as defined in claim 5 further including the step of providing an inert gas atmosphere disposed around the graphene on the substrate and the opposing wear member.
9 . The method as defined in claim 8 wherein the inert gas consists essentially of at least one of N 2 and Ar.
10 . The method as defined in claim 8 wherein the inert gas environment is a high vacuum.
11 . The method as defined in claim 3 wherein the step of disposing is done in ambient conditions.
12 . The method as defined in claim 5 wherein the opposing wear member is pre-processed to control surface roughness.
13 . A graphene wear member article of manufacture, comprising:
a first substrate;
a solution of graphene and a liquid, thereby forming a solution processed graphene disposed on the first substrate; and
a second substrate forming an opposing wear member of the solution processed graphene on the first substrate.
14 . The graphene wear member as defined in claim 12 wherein the first substrate is selected from the group of a steel, a transition metal and an insulator.
15 . The graphene wear member as defined in claim 13 wherein the transition metal is selected from the group of Cu and Ni.
16 . The graphene wear member as defined in claim 13 wherein the insulator comprises SiO 2 .
17 . The graphene wear member as defined in claim 13 wherein the liquid comprises at least one of water, alcohol or hydrocarbon based solvent.
18 . The graphene wear member as defined in claim 13 wherein the second substrate comprises a metal.
19 . The graphene wear member as defined in claim 13 wherein the second substrate comprises DLC on an underlying substrate.
20 . The graphene wear member as defined in claim 13 further including an atmosphere surrounding the graphene wear member consisting of at least one of N 2 , Ar and a high vacuum.