# US 11,993,546 B2 · Ceramic matrix composites, and methods and systems for making same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,993,546 B2 - Document ID: US11993546B2 - Status: Granted - Kind: B2 - Application number: 17/409,723 - Filed: 2021-08-23 - Published: 2021-12-09 - Granted: 2024-05-28 - Earliest claimed: 2017-05-24 - Assignees: Lancer Systems L.P. - Applicants: Lancer System L.P. - Inventors: Kenneth Church; Timothy J. Edwards; Terry A. Herb; Christopher Corrado - Web page: https://patentgrep.com/patent/US11993546B2 ## CPC - C04B 35/80: Fibres, filaments, whiskers, platelets, or the like - B28B 1/52: specially adapted for producing articles from mixtures containing fibres, {e.g. asbestos cement}(by wrapping on to mandrels B28B1/42) - B28B 11/24: for curing, setting or hardening (processes for influencing or modifying the setting or hardening ability of mortars, concrete or artificial stone compositions, in general C04B40/00) - B28B 11/243: {Setting, e.g. drying, dehydrating or firing ceramic articles (B28B11/242 takes precedence)} - B28B 19/00: Machines or methods for applying the material to surfaces to form a permanent layer thereon (making shaped articles on mandrels B28B1/30; applying liquids or other fluent materials to surfaces in general B05C; glazing or engobing C04B) - B28B 23/0006: {the reinforcement consisting of aligned, non-metal reinforcing elements} - B28B 23/022: {Means for inserting reinforcing members into the mould or for supporting them in the mould (inserting during extrusion B28B3/2645)} - C04B 35/5603: {with a well-defined oxygen content, e.g. oxycarbides} - C04B 35/571: obtained from {Si-containing} polymer precursors {or organosilicon monomers} - C04B 35/589: obtained from {Si-containing} polymer precursors {or organosilicon monomers} - C04B 35/6263: {characterised by their solids loadings, i.e. the percentage of solids} - C04B 35/6268: {characterised by the applied pressure or type of atmosphere, e.g. in vacuum, hydrogen or a specific oxygen pressure} - D04C 1/00: Braid or lace, e.g. pillow-lace; Processes for the manufacture thereof - C04B 2235/3826: Silicon carbides - C04B 2235/48: Organic compounds becoming part of a ceramic after heat treatment, e.g. carbonising phenol resins - C04B 2235/5244: Silicon carbide - C04B 2235/5248: Carbon, e.g. graphite - C04B 2235/602: Making the green bodies or pre-forms by moulding - C04B 2235/616: Liquid infiltration of green bodies or pre-forms - C04B 2235/6581: Total pressure below 1 atmosphere, e.g. vacuum - C04B 2235/96: Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - B28B: SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER (foundry moulding B22C; working stone or stone-like material B28D; shaping of substances in a plastic state, in general B29C; making layered products not composed wholly of these substances B32B) - D04C: BRAIDING OR MANUFACTURE OF LACE, INCLUDING BOBBIN-NET OR CARBONISED LACE; BRAIDING MACHINES; BRAID; LACE (machines for making soles from strips of material A43D29/00; cane working B27J1/00) ## Abstract Methods and ceramic matrix composite articles formed thereby, as well as systems for making such ceramic matrix composite articles and carrying out such methods are disclosed herein. The methods include preparing a ceramic matrix composite by steps including (a) providing reinforcing fiber, such as carbon fiber, for impregnation; (b) heat treating the reinforcing fiber; (c) impregnating the heat treated reinforcing fiber with a composition comprising a ceramic forming polymer to form a fiber reinforced, ceramic forming polymer pre-preg; and (d) heat molding the fiber reinforced, ceramic forming polymer pre-preg to form a molded ceramic matrix composite article. ## Claims ### Claim 1 A method for preparing a ceramic matrix composite, comprising (a) providing reinforcing fiber for impregnation; (b) heat treating the reinforcing fiber; (c) impregnating the heat treated reinforcing fiber with a composition comprising a ceramic matrix forming polymer to form a fiber reinforced, ceramic matrix forming polymer pre- preg, wherein impregnating comprises introducing the heat treated reinforcing fiber to an impregnation device having a first impregnation roller and a second impregnation roller, wherein the first and the second impregnation rollers are situated so that the heat treated reinforcing fiber passes through a nip between the first and the second impregnation rollers and so that the heat treated reinforcing fiber is contacted with the composition comprising the ceramic matrix forming polymer on a top and a bottom surface thereof, and wherein the composition comprising the ceramic matrix forming polymer has a high viscosity of at least about 60,000 centipoise; and (d) heat molding the reinforcing fiber, ceramic matrix forming polymer pre-preg to form a molded ceramic matrix composite article. ### Claim 2 (depends on 1) The method according to claim 1, wherein the reinforcing fiber is provided to the impregnation device on a feeder spool and the reinforcing fiber is unwound from the feeder spool, and passes through the first and the second impregnation rollers of the impregnation device and is rewound on a second spool. ### Claim 3 (depends on 2) The method according to claim 2, wherein the composition comprising the ceramic matrix forming polymer is contacted with the reinforcing fiber so as to work the composition comprising the ceramic matrix forming polymer into the reinforcing fiber as it passes through the nip between the first impregnation roller and the second impregnation roller. ### Claim 4 (depends on 3) The method according to claim 3, wherein after the reinforcing fiber passes through the first and the second impregnation rollers on the impregnation device, step (c) further comprises introducing the reinforcing fiber leaving the first and the second impregnation rollers to a vibratory liquefaction infiltration and then further passing the reinforcing fiber through a second set of impregnation rollers prior to rewinding the reinforcing fiber, ceramic matrix forming polymer pre-preg on the second spool. ### Claim 5 (depends on 1) The method according to claim 1, wherein the reinforcing fiber is provided as a braided fiber tow. ### Claim 6 (depends on 5) The method according to claim 5, wherein step (a) further comprises braiding the fiber tow. ### Claim 7 (depends on 1) The method according to claim 1, wherein the reinforcing fiber is provided as a braided tube. ### Claim 8 (depends on 7) The method according to claim 7 1, wherein the reinforcing fiber is in the form of a braided tube and step (c) further comprises contacting the composition comprising the ceramic matrix forming polymer with the braided tube so as to work the composition comprising the ceramic matrix forming polymer into the braided tube as the braided tube passes through the nip between the first and the second impregnation roller wherein the braided tube is compressed by the rollers. ### Claim 9 (depends on 8) The method according to claim 8, wherein the method further comprises introducing the composition comprising the ceramic matrix forming polymer into a center of the braided tube before or during impregnation of the braided tube by passing it through the first and the second impregnation rollers. ### Claim 10 (depends on 1) The method according to claim 1, wherein step (b) further comprises heating the reinforcing fiber to remove sizing and then heat treating the unsized reinforcing fiber in a vacuum oven. ### Claim 11 (depends on 10) The method according to claim 10, wherein the reinforcing fiber is heated to remove the sizing at a temperature of about 600° C. to about 1,000° C. and the unsized reinforcing fiber is heated in the vacuum oven at about 1,400° C. to about 1,500° C. ### Claim 12 (depends on 11) The method according to claim 11, wherein the vacuum oven has a vacuum pressure of about 2 Torr to about 6 Torr. ### Claim 13 (depends on 11) The method according to claim 11, wherein the reinforcing fiber is heated to remove sizing at about 700° C. to about 900° C. ### Claim 14 (depends on 10) The method according to claim 10, wherein heating the reinforcing fiber in the vacuum oven softens the reinforcing fiber. ### Claim 15 (depends on 1) The method according to claim 1, wherein the reinforcing fiber is carbon fiber or silicon carbide fiber. ### Claim 16 (depends on 1) The method according to claim 1, wherein the ceramic matrix forming polymer comprises a polymer having a ceramic formula selected from a group consisting of Si-O-C, Si-C-N-O, Si-N-Si-C, Si-C, and Si-N-C. ### Claim 17 (depends on 16) The method according to claim 16, wherein the ceramic matrix forming polymer comprises a polymer having a ceramic formula Si-O-C. ### Claim 18 (depends on 17) The method according to claim 17, wherein the ceramic matrix forming polymer composition further comprises at least one additive. ### Claim 19 (depends on 18) The method according to claim 18, wherein the at least one additive comprises a silicon carbide powder and the composition is in the form of a high viscosity slurry. ### Claim 20 (depends on 19) The method according to claim 19, wherein the slurry has a viscosity of equal to or less than about 400,000 centipoise. ### Claim 21 (depends on 1) The method according to claim 1, wherein prior to step (d) the carbon fiber reinforced, ceramic matrix forming polymer pre-preg is chopped. ### Claim 22 (depends on 21) The method according to claim 21, wherein prior to step (d) the fibers of the chopped pre-preg are at least partially pulled apart. ### Claim 23 (depends on 1) The method according to claim 1, wherein step (d) further comprises loading the pre-preg into a mold to form a shaped article. ### Claim 24 A method for preparing a ceramic matrix composite, comprising (a) providing reinforcing fiber in the form of a braid or braided tube for impregnation; (b) heat treating the reinforcing fiber to remove sizing; (c) further heat treating the reinforcing fiber in a vacuum oven after heating to soften the reinforcing fiber; (d) impregnating the heat treated reinforcing fiber with a composition comprising a ceramic matrix forming polymer in the form of a high viscosity slurry to form a fiber reinforced, ceramic matrix forming polymer pre-preg; and (e) heat molding the fiber reinforced, ceramic matrix forming polymer pre-preg to form a molded ceramic matrix composite article. ### Claim 25 (depends on 24) The method according to claim 24, wherein the reinforcing fiber is carbon fiber or silicon carbide fiber. ### Claim 26 (depends on 24) The method according to claim 24, wherein prior to step (e) the fiber reinforced, ceramic matrix forming polymer pre-preg is chopped. ### Claim 27 (depends on 26) The method according to claim 26, wherein prior to step (e) the fibers of the chopped pre-preg are at least partially pulled apart. ### Claim 28 (depends on 24) The method according to claim 24, wherein the reinforcing fiber is a braided tube and the method further comprises introducing the composition comprising the ceramic matrix forming polymer into a center of the tube before or during impregnating the braided tube.