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Materials, heretofore unknown for use in bearing assemblies, which produce equal or better wear resistance at reduced materials cost have been identified. These alternatives fall into three general categories: (1) solid materials from which bushings and washers can be fabricated, (2) coatings bonded

Materials, heretofore unknown for use in bearing assemblies, which produce equal or better wear resistance at reduced materials cost have been identified. These alternatives fall into three general categories: (1) solid materials from which bushings and washers can be fabricated, (2) coatings bonded to metallic bushings and/or vanes to minimize total system wear, and (3) solid lubricant coatings placed on any bushing or vane stem to reduce friction.

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What is claimed is: 1. A variable stator vane assembly for use in a compressor section of a turbine engine, comprising: a plurality of movable stator vanes, the vanes including a wear resistant coating selected from the group consisting of tungsten carbide and modified tungsten carbide; a steel st

What is claimed is: 1. A variable stator vane assembly for use in a compressor section of a turbine engine, comprising: a plurality of movable stator vanes, the vanes including a wear resistant coating selected from the group consisting of tungsten carbide and modified tungsten carbide; a steel stator casing supporting the vanes; bushing systems positioned between the stator vanes and the stator casings, each bushing systems comprising a ceramic bushing, the ceramic bushing selected from the group of ceramic materials consisting of silicon nitride, tungsten carbide and zirconium oxide; and a topical friction modifier applied between the wear resistant coated vanes and the bushing systems, the topical friction modifier comprising a friction modifying agent and a binder selected from the group consisting of aluminum phosphate, sodium silicate and combinations thereof. 2. The stator vane assembly of claim 1 wherein the modified tungsten carbide coating applied to the stator vanes includes tungsten carbide having about 12 w/o Cobalt. 3. A variable stator vane assembly for use in a compressor section of an aircraft turbine engine, comprising: a plurality of movable vanes; a lever arm attached to the vanes for positioning the vanes; a casing having a plurality of first recessed portions, a plurality of second recessed portions and inner portions having an opening between the plurality of first and second recessed portions; a plurality of bushing assemblies positioned between the casing and the movable vanes, a bushing assembly corresponding to each vane, with the vane extending through the bushing assembly, each bushing assembly comprised of a first end, a second end and a seal tube portion intermediate between the first end and the second end; and wherein the first end, the second end and the seal tube portion are comprised of an identical wear resistant ceramic material, wherein the ceramic material is characterized by high strength and stiffness, and wherein the seal tube portion is characterized by a lower stiffness and an improved flexibility than the first end and the second end of the bushing assembly so that interface forces resulting from contact between the seal tube portion and the vane are transmitted to the ends of the bushing assembly. 4. The stator vane assembly of claim 3 wherein the wear resistant ceramic material comprising the bearing assembly is selected from the group consisting of silicon nitride, tungsten carbide and zirconia. 5. The stator vane assembly of claim 3 wherein the first end of the bushing assembly is a flanged section attached to a straight section, wherein the straight section extends into the casing opening and between the vane and the casing, and the flanged section is positioned in the first recessed portion of the casing. 6. The stator assembly of claim 3 wherein the first end of the bushing assembly further comprises of a straight section and a washer, wherein the straight section extends into casing opening and between the vane and the casing and the washer is positioned in the first recessed portion of the casing. 7. The stator vane assembly of claim 3 wherein the second end of the bushing assembly is a flanged section. 8. The stator assembly of claim 3 wherein the second end of the bushing comprises a straight section and a washer. 9. The stator vane assembly of claim 3 wherein the seal tube portion is comprised of the same wear resistant ceramic material as the first end and the second end, and wherein the seal tube portion further includes from about 10% by volume to about 35% by volume closed porosity. 10. The stator vane assembly of claim 9 wherein the seal tube portion further includes about 20% by volume closed porosity. 11. The stator vane assembly of claim 9 wherein the wear resistant ceramic material is selected from the group consisting of silicon nitride, tungsten carbide and zirconia, and wherein the elastic modulus of the seal tube portion is about 50% less than the elastic modulus of the first end and the second end so that interface forces in the seal tube area are reduced thereby reducing wear in the seal tube area. 12. The stator vane assembly of claim 3 wherein the seal tube portion includes at least two circumferentially extending apertures separated by a connecting segment. 13. The stator vane assembly of claim 12 wherein the seal tube portion has a cross-sectional profile in the form of an H. 14. The stator vane assembly of claim 12 wherein the wear resistant ceramic material comprising the bearing assembly is selected from the group consisting of silicon nitride, tungsten carbide and zirconia. 15. The stator vane assembly of claim 14 wherein the wear resistant ceramic material comprising the seal tube portion further includes up to about 20% by volume closed-pore porosity. 16. The stator vane assembly of claim 3 wherein each vane further includes a wear-resistant coating applied to at least an interface between the vane and the bushing assembly. 17. The stator assembly of claim 16 wherein the wear resistant coating is selected from the group consisting of tungsten carbide, modified tungsten carbide and titanium nitride. 18. The stator assembly of claim 17 further including a friction modifier coating applied along the interface between the coated vane and the bushing assembly. 19. The stator assembly of claim 18 wherein the friction modifier coating is an aluminum phosphate binder that further includes a friction modifying agent uniformly dispersed through the coating. 20. The stator assembly of claim 19 wherein the friction modifying agent is a carbon-based material. 21. The stator assembly of claim 18 wherein the friction modifier coating is a sodium silicate binder that further includes a friction modifying agent uniformly dispersed through the coating. 22. The stator assembly of claim 21 wherein the friction modifying agent is a carbon-based material. 23. The stator assembly of claim 16 wherein the coating is applied to a thickness of from about 0.0002 to about 0.010 inches. 24. A variable stator vane assembly for use in a compressor section of an aircraft turbine engine, comprising: a plurality of movable vanes, each vane having a vane stem, the vane stem including an applied wear-resistant coating; a lever arm attached to the vanes for positioning the vanes; a casing having a plurality of first recessed portions, a plurality of second recessed portions and inner portions having an opening between the plurality of first and second recessed portions; a plurality of bushing assemblies positioned between the casing and the movable vanes, a bushing assembly corresponding to each vane, with the vane extending through the bushing assembly, each bushing assembly comprised of a first end, a second end and a seal tube portion intermediate between the first end and the second end, wherein the first end, the second end and the seal tube portion are comprised of an identical wear resistant ceramic material, and wherein opposed surfaces of the vane stem and seal tube form an interface, wherein the ceramic material is characterized by high strength and stiffness and the seal tube portion is characterized by a lower stiffness and an improved flexibility than the first end and the second end of the bushing assembly so that interface forces resulting from contact between the seal tube portion and the vane are transmitted to the ends of the bushing assembly; and a friction modifier coating applied along the interface between the coated vane stem and the seal tube. 25. The stator assembly of claim 24 wherein the friction modifier coating is an aluminum phosphate binder that further includes a friction modifying agent uniformly dispersed through the coating. 26. The stator assembly of claim 25 wherein the friction modifying agent is a carbon-based material. 27. The stator assembly of claim 24 wherein the friction modifier coating is a sodium silicate binder that further includes a friction modifying agent uniformly dispersed through the coating. 28. The stator assembly of claim 27 wherein the friction modifying agent is a carbon-based material. 29. The stator assembly of claim 24 wherein the wear resistant coating applied to the vane stem is selected from the group consisting of tungsten carbide, modified tungsten carbide and titanium nitride. 30. The stator assembly of claim 29 wherein the coating is applied to a thickness of from about 0.0002 inches to about 0.010 inches. 31. The stator vane assembly of claim 24 wherein the wear resistant ceramic material comprising each bearing assembly is selected from the group consisting of silicon nitride, tungsten carbide and zirconia. 32. The stator vane assembly of claim 31 wherein the seal tube portion is further characterized by from about 10% to about 35% closed pore porosity. 33. The stator vane assembly of claim 32 wherein the seal tube portion is further characterized by about 20% closed pore porosity. 34. The stator vane assembly of claim 31 wherein the seal tube portion is further includes at least two circumferentially extending apertures separated by a connecting segment.