A plain bearing having a sliding layer of a bearing material thereon is described, the bearing material comprising a polymer-based matrix selected from the group comprising modified epoxy resin and polyamide/amide resin, the matrix having contained therein at least one addition selected from the group comprising: metal powder in the range from 15 to 30 vol %; a fluoropolymer in the range from 1 to 15 vol %; ceramic powder in the range from 0.5 to 20 vol %; and, silica in the range from 2 to 15 vol %.
1. A plain bearing comprising: a strong backing material substrate, the substrate having one of (i) a sliding layer of a polymer-based bearing material thereon, the polymer-based bearing material comprising a polymer-based matrix and being adhered directly to the substrate by adhesive properties of the polymer-based matrix material; and (ii) a layer of a metallic bearing material thereon, with a sliding layer of a polymer-based bearing material on the metallic bearing material, the polymer-based bearing material comprising a polymer-based matrix and being adhered directly to the metallic bearing material by adhesive properties of the polymer-based matrix material; the polymer-based matrix material selected from the group consisting of a modified epoxy resin and a polyimide/amide resin, the matrix resin having contained therein particles of a metal powder in the range from 15 to 30 vol % and particles of a fluoropolymer content lying in the range from approximately 2 to 8 vol %, and selectively including an addition selected from the group consisting of a ceramic powder in the range from 0.5 to 20 vol %, and, silica in the range from 2 to 15 vol %, wherein a total solids content of the polymer-based bearing material in the form of the particles of the metal powder, the particles of the fluoropolymer content, any ceramic powder, and any silica does not exceed 35 vol %.
2. A plain bearing according to claim 1 , wherein the modified epoxy resin consists of from 30 to 60 w/w epoxy resin and 70 to 40 w/w phenolic resin based on solid to solids content.
3. A plain bearing according to claim 1 , wherein the modified epoxy resin also contains an amino resin.
4. A plain bearing according to claim 1 , wherein the modified epoxy resin also contains vinyl resin.
5. A plain bearing according to claim 1 , wherein the modified epoxy resin is prepared from an uncured epoxy resin matrix mixture, and the uncured epoxy resin matrix mixture contains two or more distinct epoxy resin constituents.
6. A plain bearing according to claim 1 , wherein polyimide is a majority constituent in the polyimide/amide matrix resin.
7. A plain bearing according to claim 6 , wherein the polyimide/amide resin also contains a vinyl resin constituent.
8. A plain bearing according to claim 1 , wherein the metal powder is selected from the group consisting of tungsten, aluminum, copper, silver, tin, brass, bronze, stainless steel, and nickel.
9. A plain bearing according to claim 8 , wherein the metal powder comprises a mixture of different metal powders.
10. A plain bearing according to claim 9 , wherein the metal powder consists of a mixture of aluminum and tungsten metals, and the proportion of aluminum to tungsten is in the range between 30/70 and 70/30 Al/W volume %.
11. A plain bearing according to claim 10 , wherein the proportion of Al to W is approximately 40/60% Al/W by volume.
12. A plain bearing according to claim 10 , wherein the morphology of the W particles is nodular or rounded.
13. A plain bearing according to claim 10 , wherein the Al powder is of flake or platelet morphology.
14. A plain bearing according to claim 1 , wherein the metal powder comprises metal powder particles having a particle size in the range from 0.5 to 10 μm.
15. A plain bearing according to claim 1 , wherein the metal powder is selected from the group consisting of a mixture of aluminum and tin, a mixture of silver and copper, a mixture of copper and tungsten, and a mixture of silver and tungsten.
16. A plain bearing as claimed in claim 1 , wherein the metal powder comprises metal alloy particles.
17. A plain bearing according to claim 16 , wherein the metal alloy is selected from the group consisting of stainless steel, aluminum alloys, brass, and bronze.
18. A plain bearing according to claim 1 , wherein the fluoropolymer is polytetrafluoroethylene.
19. A plain bearing according to claim 1 , wherein the ceramic powder is selected from the group consisting of oxides, nitrides, carbides, silicates and sulfides.
20. A plain bearing according to claim 1 , wherein the ceramic powder content lies in the range from approximately 2 to 20 vol %.
21. A plain bearing according to claim 1 , wherein the silica content lies in the range from approximately 4 to 10 vol %.
22. A plain bearing according to claim 1 , wherein the silica comprises particles having a particle size from 20 to 50 nanometers.
23. A plain bearing according to claim 1 , wherein the silica comprises reactive silica particles, each reactive silica particle having a surface with which at least one “—OH” group is associated.
24. A plain bearing according to claim 1 , wherein the solids content added to the polymer-based matrix is from approximately 10 to 30 vol %.
25. A plain bearing according to claim 1 , further including a silane material in the range of approximately 0.2 to 3 vol %.
26. A plain bearing according to claim 25 , wherein the silane material is selected from the group consisting of: bis-(gamma-trimethoxysilylpropyl)amine and gamma-glycidoxypropyltrimethoxysilane.
27. A plain bearing according to claim 1 , wherein the layer of-metallic bearing material is selected from a group consisting of an aluminum alloy and a copper alloy.
28. A plain bearing according to claim 1 , wherein the polymer-based bearing material layer has a thickness of approximately 5 to 40 μm.
29. A plain bearing according to claim 1 , wherein the bearing material is deposited directly upon a strong backing material.
30. A plain bearing according to claim 29 , wherein the bearing material has a thickness of from approximately 40 to 100 μm.
31. A plain bearing according to claim 1 , wherein the polymer-based bearing material is applied as a liquid to the substrate.
32. A plain bearing according to claim 31 , wherein the liquid is sprayed.
33. A plain bearing comprising: a strong backing material substrate, the substrate having one of (i) a sliding layer of a polymer-based bearing material thereon, the polymer-based bearing material comprising a polymer-based matrix and being adhered directly to the substrate by adhesive properties of the polymer-based matrix material, the polymer-based matrix; and (ii) a layer of a metallic bearing material thereon with a sliding layer of a polymer-based bearing material on the metallic bearing material, the polymer-based bearing material comprising a polymer-based matrix and being adhered directly to the metallic bearing material by adhesive properties of the polymer-based matrix material; the polymer-based matrix material selected from the group consisting of a modified epoxy resin and a polyimide/amide resin, the matrix resin having contained therein particles of a metal powder in the range from 15 to 30 vol % and particles of a fluoropolymer content lying in the range from approximately 2 to 8 vol %, and selectively including an addition selected from the group consisting of a ceramic powder in the range from 0.5 to 20 vol %, and, silica in the range from 2 to 15 vol %.
34. The plain bearing according to claim 33 , wherein the layer of the metallic bearing material is positioned between the strong backing material substrate and the sliding layer of the polymer-based bearing material.
35. A plain bearing comprising: a strong backing material substrate, the substrate having a sliding layer of a polymer-based bearing material thereon and being adhered to the substrate by adhesive properties of the polymer-based matrix material, the polymer-based bearing material comprising a polymer-based matrix selected from the group consisting of a modified epoxy resin and a polyimide/amide resin, the matrix resin having contained therein particles of a metal powder in the range from 15 to 30 vol % and particles of a fluoropolymer content lying in the range from approximately 1 to 15 vol %, and selectively including an addition selected from the group consisting of a ceramic powder in the range from 0.5 to 20 vol %, and, silica in the range from 2 to 15 vol %, wherein the polymer-based bearing material includes a total content of solids addition not to exceed 35 vol % in the form of the particles of the metal powder, the particles of the fluoropolymer content, any ceramic powder, and any silica.