US4172107A
Expired / Lapsed
US
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Method of manufacturing composite ceramic articles
Assignee: Toshiba Corp
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Filing: 1977-05-26
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Granted: 1979-10-23
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Expires: 1997-05-26
Abstract
Abstract Composite ceramic articles formed by integrally assembling a plurality of previously molded constituent members without applying an adhesive to their joints and designed to have a density higher than 98% of the theoretical value, and a flexural strength greater than 50 kg/cm 2 at 1200° C., and a method of producing ceramic articles of particularly complex shape which comprises the steps of previously molding a plurality of constituent members of complex shape and later integrally assembling said constituent members without applying an adhesive to their joints.
Inventors
- 👤 Kiyoshi Nakamura
- 👤 Takashi Ishii
- 👤 Michiyasu Komatsu
- 👤 Tadashi Miyano
- 👤 Masae Nakanishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:15
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/581; C04B35/56; C04B35/565; C04B35/575; C04B35/584; C04B35/593; C04B35/622; C04B35/64; C04B35/645; C04B37/00; C04B37/001; F; F01; F01D; F01D5/00; F01D5/12; F01D5/28; F01D5/284; C04B2235/00; C04B2235/65; C04B2235/656; C04B2235/6562; C04B2235/6565; C04B2235/6567; C04B2235/658; C04B2235/6587; C04B2237/00; C04B2237/30; C04B2237/32; C04B2237/36; C04B2237/365; C04B2237/366; C04B2237/368; C04B2237/50; C04B2237/64; C04B2237/70; C04B2237/704; C04B2237/76; Y; Y10; Y10S; Y10S264/00; Y10S264/50
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
142 words
A method for manufacturing a strong, fully integrated composite ceramic article having a complex shape which comprises the steps of: (a) molding raw ceramic powder into a plurality of constituent members which fit together to form said shape; (b) preliminarily sintering each of the constituent members until separate moldings each have a density greater than 70% of the theoretical density but less than the density of the resulting composite article are produced; (c) assembling each of the preliminarily sintered moldings of step (b) into a block in the form of said shape; and (d) hot pressing the thus assembled block under uniform pressure in a powder packing pressure-transmitting medium, integrally bonding the preliminarily sintered constituent members directly to each other, the thus bonded block having density greater than 98% of the theoretical density through each of said constituent members forming said block.
Claim 2
Independent Claim
142 words
A method for manufacturing a strong, fully integrated composite ceramic article having a complex shape which comprises the steps of: (a) molding raw ceramic powder into a plurality of constituent members which fit together to form said shape; (b) preliminarily sintering each of the constituent members until separate moldings each have a density greater than 70% of the theoretical density but less than the density of the resulting composite article are produced; (c) assembling each of the preliminarily sintered moldings of step (b) into a block in the form of said shape; and (d) hot pressing the thus assembled block under uniform pressure in a powder packing pressure-transmitting medium, integrally bonding the preliminarily sintered constituent members directly to each other, the thus bonded block having density greater than 98% of the theoretical density through each of said constituent members forming said block.
Claim 3
Dependent Claim
34 words
A method of manufacturing a composite ceramic article according to claim 1, wherein the powder packing used as a pressure-transmitting medium is selected from the group consisting of boron nitride powder and carbon powder.
Claim 4
Dependent Claim
27 words
A method of manufacturing a composite ceramic article according to claim 1, wherein the preliminary sintering process is carried out by burying the molding in powder packing.
Claim 5
Dependent Claim
41 words
A method of manufacturing a composite ceramic article according to claim 3, wherein the powder used as packing is powder of at least one material selected from the group consisting of carbon, silicon carbide, silicon nitride, aluminium nitride, and boron nitride.
Claim 6
Dependent Claim
41 words
A method of manufacturing a composite ceramic article according to claim 1, wherein the composite ceramic article is a turbine rotor; and the blades and hub of said turbine rotor are separately molded in advance and, after preliminary sintering, integrally assembled.
Claim 7
Dependent Claim
40 words
A method of manufacturing a composite ceramic article according to claim 1, wherein the raw ceramic powder consists of more than 70% by weight of ceramic material selected from the group consisting of silicon nitride, aluminum nitride and silicon carbide.
Claim 8
Dependent Claim
43 words
A method of manufacturing a composite ceramic article according to claim 6, wherein the raw ceramic powder is formed of more than 65% by weight of silicon nitride, less than 30% by weight of yttria and less than 5% by weight of alumina.
Claim 9
Dependent Claim
31 words
A method of manufacturing a composite ceramic article according to claim 1 wherein the theoretical density of the preliminarily sintered constituent member is in the range of 70% to about 75%.
Claim 10
Independent Claim
175 words
A method of manufacturing a strong, fully integrated composite ceramic article having a complex shape, said process comprising the steps of: (a) molding a raw ceramic powder into a plurality of separate constituent members of a predetermined shape, and ceramic material selected from the group consisting of silicon nitride, aluminum nitride and silicon carbide; (b) preliminarily sintering each of the constituent members until separate moldings each having a density greater than 70% of the theoretical density but less than the density of the resulting composite article are produced; (c) assembling each of the preliminarily sintered moldings of step (b) into a block having a predetermined shape; and (d) hot pressing the thus assembled block in a powder packing pressure-transmitting medium under conditions of continuously increasing heat and pressure, integrally bonding each of the preliminarily sintered constituent members directly to each other at their points of attachment, and continuing said hot pressing until a density greater than 98% of the theoretical density is obtained and the variation of density within the resulting article is within ±5%.
Claim 11
Independent Claim
175 words
A method of manufacturing a strong, fully integrated composite ceramic article having a complex shape, said process comprising the steps of: (a) molding a raw ceramic powder into a plurality of separate constituent members of a predetermined shape, and ceramic material selected from the group consisting of silicon nitride, aluminum nitride and silicon carbide; (b) preliminarily sintering each of the constituent members until separate moldings each having a density greater than 70% of the theoretical density but less than the density of the resulting composite article are produced; (c) assembling each of the preliminarily sintered moldings of step (b) into a block having a predetermined shape; and (d) hot pressing the thus assembled block in a powder packing pressure-transmitting medium under conditions of continuously increasing heat and pressure, integrally bonding each of the preliminarily sintered constituent members directly to each other at their points of attachment, and continuing said hot pressing until a density greater than 98% of the theoretical density is obtained and the variation of density within the resulting article is within ±5%.
Claim 12
Independent Claim
170 words
A method of manufacturing a strong, fully integrated composite ceramic article having a complex shape, said process comprising the steps of: (a) molding a raw ceramic powder into a plurality of separate constituent members of a predetermined shape, and ceramic material selected from the group consisting of silicon nitride, aluminum nitride and silicon carbide; (b) preliminarily sintering each of the constituent members until separate moldings each having a density of at least 65% and up to 75% of the theoretical density are produced; (c) assembling each of the preliminarily sintered moldings of step (b) into a block having a predetermined shape; and (d) hot pressing the thus assembled block in a powder packing pressure-transmitting medium under conditions of continuously increasing heat and pressure, integrally bonding each of the preliminarily sintered constituent members directly to each other at their points of attachment, and continuing said hot pressing until a density greater than 98% of the theoretical density is obtained and the variation of density within the resulting article is within ±5%.
Claim 13
Independent Claim
170 words
A method of manufacturing a strong, fully integrated composite ceramic article having a complex shape, said process comprising the steps of: (a) molding a raw ceramic powder into a plurality of separate constituent members of a predetermined shape, and ceramic material selected from the group consisting of silicon nitride, aluminum nitride and silicon carbide; (b) preliminarily sintering each of the constituent members until separate moldings each having a density of at least 65% and up to 75% of the theoretical density are produced; (c) assembling each of the preliminarily sintered moldings of step (b) into a block having a predetermined shape; and (d) hot pressing the thus assembled block in a powder packing pressure-transmitting medium under conditions of continuously increasing heat and pressure, integrally bonding each of the preliminarily sintered constituent members directly to each other at their points of attachment, and continuing said hot pressing until a density greater than 98% of the theoretical density is obtained and the variation of density within the resulting article is within ±5%.
References Cited (Backward Citations)
US4071372A
Cited
US3989438A
Cited
US3892835A
Cited
US3776744A
Cited
US3886254A
Cited
US3905723A
Cited
US3887412A
Cited
US3887411A
Cited
US3854189A
Cited
US4087500A
Cited
US4075276A
Cited
US3885294A
Cited
US4011295A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-10-22 | 1983-04-23 | 1983-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-22 | 1987-04-23 | 1987-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-22 | 1991-04-23 | 1991-10-23 | $7700.00 | Window Closed / Lapsed |