# US 2019/0316632 A1 · Air bearing shaft assembly with surface layer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0316632 A1 - Document ID: US20190316632A1 - Status: Published application - Kind: A1 - Application number: 15/952,748 - Filed: 2018-04-13 - Published: 2019-10-17 - Earliest claimed: 2018-04-13 - Assignees: Hamilton Sundstrand Corporation - Applicants: Hamilton Sundstrand Corporation - Inventors: Steven Poteet; Blair A. Smith; Kevin M. Rankin; William R. Fiske - Web page: https://patentgrep.com/patent/US20190316632A1 ## CPC - F16C 33/1095: {with solids as lubricant, e.g. dry coatings, powder} - F16C 17/024: {with flexible leaves to create hydrodynamic wedge, e.g. radial foil bearings} - F16C 17/042: {with flexible leaves to create hydrodynamic wedge, e.g. axial foil bearings} - F16C 32/0607: {the gas being retained in a gap, e.g. squeeze film bearings} - F16C 33/043: {Sliding surface consisting mainly of ceramics, cermets or hard carbon, e.g. diamond like carbon [DLC]} - F01D 25/16: Arrangement of bearings; Supporting or mounting bearings in casings (bearings per se F16C) - F01D 25/166: {Sliding contact bearing (gas bearings F01D25/22)} - F05D 2240/50: Bearings - F16C 33/1005: {with gas, e.g. air, as lubricant} - F16C 2202/04: Hardness - F16C 2206/04: Diamond like carbon [DLC] - F16C 2206/82: based on tungsten carbide [WC] - F16C 2223/30: Coating surfaces - F16C 2223/60: by vapour deposition, e.g. PVD, CVD - F16C 2240/60: Thickness, e.g. thickness of coatings - F16C 2360/23: Gas turbine engines - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract An example embodiment of an air bearing assembly includes a first member and a shaft with a flange configured to rotate with respect to the first member. The first member has a first coating on at least one first surface facing at least one second surface on the flange or the shaft. The first coating includes tungsten carbide, a nonpolymeric self-lubricating coating, or a combination thereof. At least one of the second surfaces has a second coating on a surface facing the first coating. ## Claims ### Claim 1 An air bearing assembly, comprising: a journal; and a shaft configured to rotate with respect to the journal; a flange connected to and extending from an end of the shaft; wherein the journal has a first coating disposed on a first surface facing a second surface on the shaft, the first coating comprising tungsten carbide, a nonpolymeric self-lubricating coating, or a combination thereof; and wherein the second surface has a second coating disposed on a surface that faces the first coating, the second coating comprising tungsten carbide, a nonpolymeric self-lubricating coating, or a combination thereof. ### Claim 2 (canceled) ### Claim 3 (depends on 1) The air bearing assembly of claim 1, wherein the first coating can withstand an operating temperature above 550° F. (about 288° C.). ### Claim 4 (depends on 1) The air bearing assembly of claim 1, wherein the first coating can withstand an operating temperature above 750° F. (about 400° C.). ### Claim 5 (depends on 1) The air bearing assembly of claim 1, wherein the first coating has a thickness greater than about 0.00004 inches (1 micron) and less than about 0.002 inches (50 microns). ### Claim 6 (canceled) ### Claim 7 (depends on 1) The air bearing assembly of claim 1, wherein the second coating has a hardness of 600 Vickers or greater according to a Vickers microindentation hardness test per ASTM E384. ### Claim 8 (depends on 1) The air bearing assembly of claim 1, wherein the second coating has a thickness less than about 0.002 inches (50 microns). ### Claim 9 (canceled) ### Claim 10 (depends on 1) The air bearing assembly of claim 1, wherein the self-lubricating coating is selected from a group consisting of: diamond-like carbon (DLC), WS2, WSi2, AgO, Ag, BN, MoS2, and combinations thereof. ### Claim 11 (depends on 1) The air bearing assembly of claim 1, further comprising: a second member disposed on a side of the flange opposite the journal, wherein the second member has a third coating on a third surface facing the flange, the third coating comprising tungsten carbide, a nonpolymeric self-lubricating coating, or a combination thereof. ### Claim 12 A method of making an air bearing assembly, the method comprising: providing a journal and a shaft with a flange configured to rotate with respect to the journal; applying a first coating to a first surface of the journal, wherein the first surface of the journal faces the shaft, wherein the first coating comprises tungsten carbide, a nonpolymeric self-lubricating coating, or a combination thereof; applying a second coating to a second surface of the shaft, wherein the second surface faces the first surface; and assembling the journal to the shaft to form the air bearing assembly. ### Claim 13 (canceled) ### Claim 14 (canceled) ### Claim 15 (depends on 12) The method of claim 12, wherein the first coating is applied to the journal by one of chemical vapor deposition and physical vapor deposition. ### Claim 16 (depends on 12) The method of claim 12, wherein the first coating comprises tungsten carbide, a nonpolymeric self-lubricating coating, or a combination thereof. ### Claim 17 (depends on 16) The method of claim 16, wherein the self-lubricating coating is selected from a group consisting of: diamond-like carbon (DLC), WS2, WSi2, AgO, Ag, BN, MoS2, and combinations thereof. ### Claim 18 (depends on 12) The method of claim 12, wherein the first coating is greater than about 0.00004 inches (1 micron) thick. ### Claim 19 (depends on 12) The method of claim 12, wherein the second coating comprises tungsten carbide, a nonpolymeric self-lubricating coating, or a combination thereof. ### Claim 20 (depends on 12) The method of claim 12, wherein the first coating can withstand an operating temperature above 550° F. (about 288° C.).