EP0140682A1
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EP
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A method for producing a ceramic article
Assignee: Hitachi Ltd
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Filing: 1984-10-26
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Granted: —
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Expires: 2004-10-26
Abstract
Abstract © A ceramic article having a complicated configuration and non-uniform in wall thickness such as a turbocharger rotor for automobiles, a rotor for gas turbine engines and the like is produced by casting a ceramic-containing slurry 1 into a mold 2,3. Problems caused by non-uniform absorption of the liquid in the slurry are avoided by effecting orientated solidification of the slurry in the mold. Part 2 of the mold is absorptive, while part 3 is non-absorptive.
Inventors
- 👤 Junji Sakai
- 👤 Keiichi Kuniya
- 👤 Masahisa Sobue
- 👤 Tetsuo Nakazawa
- 👤 Toshimi Sasaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 11:21
CPC Classifications
B; B28; B28B; B28B1/00; B28B1/26; B28B1/261; C; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
26 words
A method for producing a ceramic article, which comprises casting a ceramic-containing slurry into a mold and effecting orientated solidification of the slurry in the mold.
Claim 2
Independent Claim
26 words
A method for producing a ceramic article, which comprises casting a ceramic-containing slurry into a mold and effecting orientated solidification of the slurry in the mold.
Claim 3
Dependent Claim
28 words
A method for producing a ceramic article according to claim 1, wherein orientated solidification is effected by removing water in the slurry from a part of said mold.
Claim 4
Dependent Claim
25 words
A method for producing a ceramic article according to claim 2, wherein water in the slurry is removed from the bottom portion of said mold.
Claim 5
Dependent Claim
34 words
A method for producing a ceramic article according to claim 2 or claim 3, wherein a part of said mold is constituted by a water-absorptive material to thereby absorb away water in the slurry.
Claim 6
Independent Claim
39 words
A method for producing a ceramic article according to any one of claims 1 to 4, wherein said ceramic-containing slurry contains water in an amount of 20 to 50 parts by weight to 100 parts by weight of ceramic.
Claim 7
Independent Claim
22 words
A method for producing a ceramic article according to any one of claims 1 to 5, wherein said ceramic is silicon carbide.
Claim 8
Dependent Claim
25 words
A method for producing a ceramic article according to claim 6, wherein said silicon carbide has an average particle size of 1 µm or less.
Claim 9
Independent Claim
49 words
A method for producing a ceramic article according to any one of claims 1 to 7, wherein said ceramic-containing slurry contains water in an amount of 12 to 50 parts by weight to 100 parts by weight of silicon carbide, as well as a sintering aid and a deflocculant.
Claim 10
Independent Claim
31 words
A method for producing a ceramic article according to any one of claims 1 to 8 wherein the mold is constituted by a water-absorptive mold portion and a non-water-absorptive mold portion.
Claim 11
Dependent Claim
20 words
A method for producing a ceramic article according to claim 9, wherein said water-absorptive mold portion is made of gypsum.
Claim 12
Dependent Claim
23 words
A method for producing a ceramic article according to claim 9 or claim 10, wherein said non-water-absorptive mold portion is made of rubber.
Claim 13
Independent Claim
61 words
A method for producing a ceramic article according to any one of claims 9 to 11, wherein the lower region of said mold including its bottom portion is constituted by said water-absorptive mold portion and the other part is constituted by said non-water-absorptive mold portion so as to absorb away water in the slurry from the lower section of the mold.
Claim 14
Independent Claim
34 words
A method for producing a ceramic article according to any one of the preceding claims, wherein the ceramic-containing slurry is subjected to a degassing treatment under reduced pressure prior to casting into the mold.
Claim 15
Dependent Claim
28 words
A method for producing a ceramic article according to claim 13, wherein said degassing treatment is conducted at a reduced pressure of 70 to 80 cmHg or below.
Claim 16
Independent Claim
26 words
A method for producing a ceramic article according to any one of the preceding claims wherein said ceramic-containing slurry is cast into the mold under pressure.
Claim 17
Dependent Claim
25 words
A method for producing a ceramic article according to claim 15 wherein the pressure applied to the slurry is 0.1 to 1 kg/cm 2 .
Claim 18
Independent Claim
25 words
A method for producing a ceramic article according to any one of the preceding claims including the step of pressing the slurry in the mold.
Claim 19
Independent Claim
30 words
A method for producing a ceramic article according to any one of the preceding claims including the step, after casting the ceramic-containing slurry into the mold, of heating the slurry.
Claim 20
Dependent Claim
34 words
A method for producing a ceramic article according to claim 18, wherein a part of said mold is constituted by a water-absorptive material and the slurry is heated by heating said water-absorptive mold part.
Claim 21
Dependent Claim
32 words
A method for producing a ceramic article according to claim 19, wherein said water-absorptive mold part is made of gypsum and this gypsum mold part is heated to a temperature below 70°C.
Claim 22
Independent Claim
35 words
A method for a ceramic article according to any one of the preceding claims further including the step of placing the interior of the mold, into which said slurry has been cast, under reduced pressure.
Claim 23
Dependent Claim
31 words
A method for producing a ceramic article according to claim 21, wherein the interior of the mold is place under reduced pressure after the slurry in the mold has been solidified.
Claim 24
Dependent Claim
30 words
A method for producing a ceramic article according to claim 21, including the step of placing the interior of the mold under reduced pressure during the solidification of the slurry.
Claim 25
Independent Claim
26 words
A method for producing a ceramic article according to any one of claims 1 to 20 including the step of casting the slurry under reduced pressure.
Claim 26
Independent Claim
111 words
A method for producing a ceramic article, which comprises subjecting a slurry containing water in an amount of 35 to 45 parts by weight to 100 parts by weight of silicon carbide with an average particle size of 1 µm or less and also containing a sintering aid and a deflocculant to a degassing treatment under reduced pressure, then returning the slurry into the atmospheric air, casting said slurry into a mold constituted from a water-absorptive mold and a non-water-absorptive mold, absorbing away water in the slurry by said water-absorptive mold to effect orientated solidification of the slurry, taking out the solidified product from said mold, drying and sintering said product.
Claim 27
Independent Claim
111 words
A method for producing a ceramic article, which comprises subjecting a slurry containing water in an amount of 35 to 45 parts by weight to 100 parts by weight of silicon carbide with an average particle size of 1 µm or less and also containing a sintering aid and a deflocculant to a degassing treatment under reduced pressure, then returning the slurry into the atmospheric air, casting said slurry into a mold constituted from a water-absorptive mold and a non-water-absorptive mold, absorbing away water in the slurry by said water-absorptive mold to effect orientated solidification of the slurry, taking out the solidified product from said mold, drying and sintering said product.
References Cited (Backward Citations)
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