# US 12,759,945 B2 · Fabrication of near net-shaped silicon carbide structures > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,759,945 B2 - Document ID: US12759945B2 - Status: Granted - Kind: B2 - Application number: 18/365,115 - Filed: 2023-08-03 - Published: 2025-02-06 - Granted: 2026-10-13 - Earliest claimed: 2023-08-03 - Assignees: General Atomics - Applicants: General Atomics - Inventors: Jiping Zhang; Jonas Opperman; George Jacobsen; Bunsen Wong - Web page: https://patentgrep.com/patent/US12759945B2 ## CPC - C04B 35/573: obtained by reaction sintering {or recrystallisation} - C04B 35/63464: {Polycarbonates} - C04B 35/638: Removal thereof - C04B 35/65: Reaction sintering of free metal- or free silicon-containing compositions {(C04B35/573, C04B35/591 take precedence)} - C04B 38/0032: {one of the precursor materials being a monolithic element having approximately the same dimensions as the final article, e.g. a paper sheet which after carbonisation will react with silicon to form a porous silicon carbide porous body} - C04B 2235/3418: Silicon oxide, silicic acids or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint - C04B 2235/3826: Silicon carbides - C04B 2235/422: Carbon - C04B 2235/428: Silicon - 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 ## Abstract A method of manufacturing a target structure is provided. The method includes: obtaining a model structure of an initial material composition having a predetermined geometry and dimensions; applying a slurry mixture into the model structure; and processing the model structure with the slurry mixture inside the model structure to convert the initial material composition of the model structure into a final material composition to obtain the target structure with the final material composition and having a geometry and dimensions that are substantially similar to the predetermined geometry and dimensions of the model structure. ## Claims ### Claim 1 A method of manufacturing a target structure, comprising: obtaining a model structure of an initial material composition having a predetermined geometry and dimensions; applying a slurry mixture into the model structure, wherein the slurry mixture comprises silicon particles coated with silicon dioxide exterior layers; and processing the model structure with the slurry mixture inside the model structure to convert the initial material composition of the model structure into a final material composition to obtain the target structure with the final material composition and having a geometry and dimensions that are substantially similar to the predetermined geometry and dimensions of the model structure, wherein the processing comprises: generating a product including a silicon monoxide gas in-situ within the model structure from a first reaction between silicon and silicon dioxide of the slurry mixture; and converting the initial material composition to the final material composition by reacting the silicon monoxide gas with the model structure in a second reaction. ### Claim 2 (depends on 1) The method of claim 1, wherein the model structure comprises a plurality of pores, and wherein the applying the slurry mixture into the model structure comprises applying the slurry mixture into the plurality of pores of the model structure. ### Claim 3 (depends on 2) The method of claim 2, wherein the initial material composition of the model structure comprises a model material composition, and the final material composition of the target structure comprises a target material composition. ### Claim 4 (depends on 3) The method of claim 3, wherein in the slurry mixture, one or more of the silicon (Si) particles coated with the silicon dioxide (SiO2) exterior layers are half oxide silicon particles (HOSP) having a molar ratio of Si to SiO2 to be around one. ### Claim 5 (depends on 4) The method of claim 4, wherein generating the product of the first reaction comprises generating the silicon monoxide (SiO) gas in-situ inside the model structure by increasing a temperature around the model structure with the slurry mixture inside the model structure to over 1200° C. under 10 mTorr to allow occurrence of the first reaction between SiO2 and Si of the slurry mixture inside the model structure, and wherein the first reaction is SiO2+Si=2SiO(g). ### Claim 6 (depends on 5) The method of claim 5, wherein the model structure is converted to the target structure through the second reaction between the SiO gas and C inside the model structure, wherein the second reaction is SiO(g)+2C=CO(g)+SiC. ### Claim 7 (depends on 4) The method of claim 4, wherein the step of applying the slurry mixture into the model structure comprises: providing the model structure in a container in a chamber; submerging the model structure in at least a portion of the slurry mixture by vacuuming air out of the chamber to 10-100 mTorr at 25° C. to suck the at least the portion of the slurry mixture from outside the chamber to the container in the chamber; applying the at least the portion of the slurry mixture into the plurality of pores of the model structure by applying a pressure in the chamber at 50-250 Psi and at 25° C.; releasing a pressure in the chamber after the at least the portion of the slurry mixture is inside the plurality of pores of the model structure; and drying the model structure with the at least the portion of the slurry mixture inside the plurality of pores of the model structure. ### Claim 8 (depends on 3) The method of claim 3, wherein the slurry mixture further comprises a fugitive binder that decomposes at 300° C., and the model material composition is compositionally different from the target material composition. ### Claim 9 (depends on 8) The method of claim 8, wherein the fugitive binder comprises poly (propylene carbonate). ### Claim 10 (depends on 3) The method of claim 3, wherein: the model material composition is compositionally different from the target material composition, and the second reaction is between the product of the first reaction and the model structure. ### Claim 11 (depends on 10) The method of claim 10, wherein the model material composition is carbon (C), and the target material composition is silicon carbide (SiC). ### Claim 12 (depends on 3) The method of claim 3, wherein: the model material composition is compositionally the same as the target material composition, and the second reaction is between the product of the first reaction and a third material contained within the slurry mixture inside the model structure. ### Claim 13 (depends on 12) The method of claim 12, wherein the slurry mixture further comprises a carbon-producing resin that is converted to carbon as the third material at 900° C., and the density of the model structure is lower than the density of the target structure. ### Claim 14 (depends on 12) The method of claim 12, wherein: the model material composition and the target material composition include silicon carbide materials, and the third material is carbon. ### Claim 15 (depends on 1) The method of claim 1, further comprising: making a volume difference between the target structure and the model structure be within five percent of a volume of the model structure. ### Claim 16 (depends on 1) The method of claim 1, wherein the target structure has a phase purity greater than 95%. ### Claim 17 A method of manufacturing a target structure, comprising: obtaining a model structure of an initial material composition having a predetermined geometry and dimensions; applying a slurry mixture into the model structure; and processing the model structure with the slurry mixture inside the model structure to convert the initial material composition of the model structure into a final material composition to obtain the target structure with the final material composition and having a geometry and dimensions that are substantially similar to the predetermined geometry and dimensions of the model structure, wherein: the processing the model structure with the slurry mixture inside the model structure comprises: generating a product of a first reaction between two or more components of the slurry mixture inside the model structure; and converting the model structure to the target structure through a second reaction based on the product of the first reaction; the model structure comprises a plurality of pores, and wherein the applying the slurry mixture into the model structure comprises applying the slurry mixture into the plurality of pores of the model structure; the slurry mixture comprises one or more silicon (Si) particles coated with silicon dioxide (SiO2) exterior layers that are half oxide silicon particles (HOSP) having a molar ratio of Si to SiO2 to be around one; and the Si particles coated with SiO2 is are prepared by a process including: providing a plurality of Si particles in a fluidized bed chamber; flowing oxygen (O2) over the plurality of Si particles at a temperature between 900° C. and 1100° C. in the fluidized bed chamber to cause surface oxidation of the plurality of Si particles to form SiO2; and stopping flowing O2 when the molar ratio of Si to SiO2 is around one. ### Claim 18 (depends on 17) The method of claim 17, further comprising: making a volume difference between the target structure and the model structure be within five percent of a volume of the model structure. ### Claim 19 (depends on 17) The method of claim 17, wherein the target structure has a phase purity greater than 95%. ### Claim 20 (depends on 17) The method of claim 17, wherein the generating the product of the first reaction comprises generating a silicon monoxide (SiO) gas in-situ inside the model structure.