United States of America As Represented by the Secretary of the Air Force

Cleveland State University

Nelson H Forster

Lewis Rosado

Edgar E Graham

Christopher J Klenke

James P King

Rabi S Bhattacharya

Amarendra K Rai

Hitesh K Trivedi

Wei T Shih

Garry D Givan

The present invention provides a method for applying a tribological coating to a carbon composite substrate. The method includes providing the carbon composite substrate, depositing a layer of carbon on the substrate, applying a layer of aluminum on the layer of carbon, annealing the substrate at a temperature greater than a melting temperature of aluminum, and applying a layer of silver. A layer of mixed aluminum and silver may be substituted for the layer of silver.

Metal coatings for reduced friction in composites

A bi-directional, conical carbon-carbon clutch bearing engagement mechanism for the inner race of a conventional rolling element bearing comprising a plurality of wave springs for axially urging the clutch into a non-engaged position, and a guide consisting of contiguous pairs of non-parallel ball raceways and a ball positioned in both pairs of the ball raceways whereby relative rotation of the ball raceway pairs in opposite directions results in axial movement of the clutch ring housings in opposing axial directions to an engaged position. The mechanism includes a pair of conical carbon-carbon rings mounted in the movable clutch ring housings conformed to engage opposing conical shaft runners.

Carbon-carbon clutch bearing engagement mechanism

A novel rolling element bearing assembly comprises an inner race, an outer race, a plurality of rolling elements, and a carbon-carbon composite retainer. The carbon-carbon composite retainer is fabricated by providing a woven tube, cutting the woven tube into suitably sized rings, piercing the rings for rolling bearing elements, and densifying the resulting retainer. Alternatively, the tube can be densified, then cut into a plurality of retainer blanks which are then pierced. For use at operating temperatures above about 650.degree. C., ceramic coatings, such as silicon carbide (SiC), silicon nitride (Si.sub.3 N.sub.4) and boron nitride (BN) can be used to provide oxidation resistance for the carbon-carbon composite retainer at such elevated temperatures.

High temperature rolling element bearing

Substituted biphenyl sulfones of the formula: ##STR1## wherein R is ##STR2## wherein Z is --H, --CH.sub.3, --CF.sub.3, --F, --OCH.sub.3 or --OCF.sub.3 ; and R' is --R or --H, are useful as lubricants in the temperature range of up to about 750.degree. F.

Powdered sulfones as high temperature lubricants

A method for lubricating a ceramic bearing surface which comprises applying a cesium-containing compound selected from the group consisting of Cs.sub.2 MoO.sub.4, Cs.sub.2 SO.sub.4, Cs.sub.2 WO.sub.4, Cs.sub.2 WOS.sub.3, Cs.sub.2 MoOS.sub.3 and CsOH, to the bearing surface and heating the thus-coated bearing surface to a temperature of about 300.degree. C. or greater. Alternatively, the cesium-containing compound may be applied in admixture with a lower alkali metal silicate. This method is particularly useful for lubricating the bearings in expendable, high temperature turbine engines, such as those used in expendable missiles.

High temperature cesium-containing solid lubricant

Metal and/or ceramic bearing lubrication is provided over a utilization temperature range extending from about -50.degree. C. up to at least 500.degree. C. and higher with a blended mixture of a vaporizable and polymerizable aryl ester contained in a liquid alpha olefin oligomer. Vapor-phase polymerization of the aryl phosphate ester occurs during bearing operation to produce a polymer lubricating coating on at least one of the treated bearing surfaces.

Bearing lubrication means having wide temperature utilization

Metal and ceramic bearing means being operated at elevated temperatures of at least 300.degree. C. and higher under atmospheric conditions are effectively lubricated with a novel class of vapor-phase deposited polymer lubricants. The lubricants are formed in situ during bearing operation and can further be applied as a precoat upon at least one of the untreated bearing surfaces for subsequent operation in the same manner.

High temperature lubrication for metal and ceramic bearings

System and method for high temperature lubrication of a bearing surface of a movable machine part using lubricant sublimation is described which comprises a source of solid lubricant, a heater disposed in thermal contact with the lubricant for heating the lubricant to sublimation and a conduit for conducting sublimated lubricant vapors into contact with the bearing surface to be lubricated.

Growing community of inventors

Dayton, OH, United States of America

Nelson H Forster