Sub-stoichiometric metal nitrides
A non-stoichiometric nanocomposite coating and method of making and using the coating. The non-stoichiometric nanocomposite coating is disposed on a base material, such as a metal or ceramic; and the nanocomposite consists essentially of a matrix of an alloy selected from the group of Cu, Ni, Pd, Pt and Re which are catalytically active for cracking of carbon bonds in oils and greases and a grain structure selected from the group of borides, carbides and nitrides.
1. A super lubricious apparatus comprising:
a substrate;
a nanocomposite coating on the substrate, the nanocomposite consisting essentially of a matrix of a catalytically active element embedded in the matrix, the matrix selected from Cu, Ni, Pd, Pt and Re and mixtures thereof, and non-stoichiometric vanadium nitride grains;
a hydrocarbon lubricant; and
a carbon film disposed between the nanocomposite coating and the hydrocarbon lubricant.
2. The apparatus as defined in claim 1 , wherein the catalytically active element is about 1% to 10% by weight and the grains are from about 90% to 99% by weight.
3. The apparatus as defined in claim 1 , wherein the substrate is selected from the group of a metal and a ceramic.
4. The apparatus as defined in claim 1 , wherein the substrate comprises a steel based material.
5. The apparatus as defined in claim 1 , wherein the oil is essentially free of additives.
6. The apparatus as defined in claim 1 , wherein the carbon film consists essentially of diamond like carbon.
7. A method for lubricating materials in wear contact, comprising the steps of:
providing a base material;
disposing a non-stoichiometric nanocomposite coating on the base material, the nanocomposite consisting essentially of about 1% to 10% by weight a microstructural matrix of a catalytically active alloy with about 90% to 99% by weight grains embedded in therein, the microstructural matrix selected from the group of Cu, Ni, Pd, Pt and Re and mixtures thereof and vanadium nitride grains;
disposing an oil on the nanocomposite coating;
engaging the nanocomposite coating with a surface, the oil disposed therebetween;
cracking carbon bonds of the oil; and
forming a carbon film disposed between the coating and the layer, thereby lubricating the nanocomposite coating and underlying base material.
8. The method as defined in claim 7 , wherein the base material is selected from the group of a metal and a ceramic.
9. The method as defined in claim 7 , wherein the base material comprises a steel based material.
10. The method as defined in claim 7 , wherein the oil is essentially free of additives.
11. The method as defined in claim 7 , wherein the carbon film consists essentially of diamond like carbon.
12. The method as defined in claim 7 , wherein the grains are selected from the group of refractory metal carbides, carbo-nitrides, nitrides and borides.
13. The apparatus of claim 1 , wherein the vanadium nitride hard grains are non-stoichiometric.
14. The apparatus of claim 1 , wherein the catalytic soft grains are homogenously distributed on the nanocomposite coating.
15. The apparatus of claim 1 , wherein the nanocomposite coating is non-stoichiometric.