Tribological synthesis method for producing low-friction surface film coating
An article of method of manufacture of a low friction tribological film on a substrate. The article includes a substrate of a steel or ceramic which has been tribologically processed with a lubricant containing selected additives and the additives, temperature, load and time of processing can be selectively controlled to bias formation of a film on the substrate where the film is an amorphous structure exhibiting highly advantageous low friction properties.
1. A method of forming a low friction tribological surface film comprising:
providing a substrate having a crystalline structure and an opposing wear member;
providing a lubricant; and
controlling operating conditions during tribological rubbing processing, to form a film on the substrate wherein the film comprises an amorphous structure formed by the tribological rubbing processing.
2. The method as defined in claim 1 wherein the substrate is selected from the group of steel and a ceramic.
3. The method as defined in claim 1 wherein the amorphous structure comprises at least about 40% of the film structure.
4. The method as defined in claim 1 wherein the lubricant comprises a fluid and an additive.
5. The method as defined in claim 4 wherein the additive is selected from the group of an additive material comprising Zn, Mo, Ca, S, P, O, N, C, B, Si, Al and Ti.
6. The method as defined in claim 5 wherein the additive material is selected from the group of a compound which releases in the lubricant an elemental form of the additive material able to interact with the substrate to form the amorphous structure.
7. The method as defined in claim 4 wherein the additive is selected from the group of a gas, a solid and a liquid.
8. The method as defined in claim 4 wherein the fluid comprises a synthetic hydrocarbon.
9. The method as defined in claim 8 wherein the fluid comprises a poly-alpha-olefin including a Mo-organic-metallic compound and a Zn-organo-metallic compound.
10. The method as defined in claim 8 wherein the fluid comprises a synthetic gear oil containing an FM additive.
11. The method as defined in claim 1 wherein the temperature of the substrate is maintained between about 40-110° C.
12. The method as defined in claim 1 wherein the substrate comprises a steel and the load level is between about 200-800N.
13. The method as defined in claim 1 wherein the substrate comprises a steel and the time of tribological processing is at least about 2000 seconds.
14. The method of claim 1 , wherein the lubricant is provided such that the λ ratio is less than 0.2.
15. The method of claim 1 , wherein the film has an average thickness of 50 nm to 120 nm.
16. A method of forming a low friction tribological surface film comprising:
providing a substrate having a crystalline structure and an opposing wear member;
providing a lubricant; and
controlling operating conditions during tribological rubbing processing, such that λ ratio is less than 0.2, to form a film on the substrate wherein the film comprises an amorphous structure formed by the tribological rubbing processing, the film having at least 30% amorphous phase.