EP0188129A2
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High toughness ceramics and process for the preparation thereof
Assignee: Hitachi Ltd
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Filing: 1985-12-24
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Granted: —
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Expires: 2005-12-24
Abstract
Abstract The present invention relates to a sintered product containing silicon carbide as a main component which comprises a phase (a) containing at least one metal selected from among AI, Sc, Y and rare earth elements and oxygen, a particle phase (b) comprising at least one metal carbide selected from among carbides of Ti, Zr, Hf, Va, Nb, Ta, W and the like, a composite particle phase (c) comprising said phase (a) and said phase (b) surrounding the phase (a) and silicon carbide matrix (d) in which the above phase (a), (b) and (c) are dispersed. The silicon carbide sintered product of the present invention exhibits a remarkably high strength and a remarkably high toughness which have not been attained up to this time, so that it can form various heat-resistant structural materials having a high reliability.
Inventors
- 👤 Hironori Kodama
- 👤 Akihiro Gotoo
- 👤 Tadahiko Miyoshi
- 👤 Hiroshi Sakamoto
- 👤 Takaaki Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 23:30
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B35/575
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
78 words
A high toughness ceramic which comprises a silicon carbide matrix (d) in which are dispersed a phase (a) containing at least one metal selected from aluminum, scandium, yttrium and rare earth elements, and oxygen; and a particle phase (b) comprising at least one metal carbide other than silicon carbide, said phases (a) and (b) optionally and/or additionally being present as a composite particle phase (c) comprising said phase (a) and said particle phase (b) surrounding the phase (a).
Claim 2
Dependent Claim
78 words
A high toughness ceramic which comprises a silicon carbide matrix (d) in which are dispersed a phase (a) containing at least one metal selected from aluminum, scandium, yttrium and rare earth elements, and oxygen; and a particle phase (b) comprising at least one metal carbide other than silicon carbide, said phases (a) and (b) optionally and/or additionally being present as a composite particle phase (c) comprising said phase (a) and said particle phase (b) surrounding the phase (a).
Claim 3
Dependent Claim
16 words
A high toughness ceramic as set forth in claim 1, wherein the phase (a) contains silicon.
Claim 4
Dependent Claim
39 words
A high toughness ceramic as set forth in claim 2, wherein the phase (a) contains a silicate of at least one metal selected from the group consisting of aluminum, scandium, yttrium and rare earth elements as a main component.
Claim 5
Dependent Claim
23 words
A high toughness ceramic as set forth in claim 3, wherein the particle phase (a) contains a silicate glass as a main component.
Claim 6
Dependent Claim
25 words
A high toughness ceramic as set forth in any preceding claim, wherein the particle phase (b) has an average particle size of 1 to 20um.
Claim 7
Dependent Claim
26 words
A high toughness ceramic as set forth in any preceding claim, wherein the silicon carbide matrix (d) has an average particle size of 0.2 to 5um.
Claim 8
Dependent Claim
31 words
A high toughness ceramic as set forth in any preceding claim, wherein the composite particle phase (c) is present in an amount of 5 to 30% by volume in the ceramic.
Claim 9
Dependent Claim
44 words
A high toughness ceramic as set forth in any preceding claim, wherein composite particle phase (c) with an average particle size of 30 to 150µm is present in an amount of at least 50% by volume of total amount of a particle phase (b).
Claim 10
Dependent Claim
62 words
A high toughness ceramic as set forth in any preceding claim, wherein the composite particle phase (c) is present in an amount of 5 to 30% by volume in the ceramic; and at least 50% by volume of the total amount of particle phase (b) is present as composite particle phase (c) of which the average particle size is 30 to 150um.
Claim 11
Dependent Claim
27 words
A high toughness ceramic as set forth in any preceding claim, wherein the phase (a) comprises an oxide of aluminum, scandium, yttrium or a rare earth metal.
Claim 12
Dependent Claim
47 words
ll. A high toughness ceramic as set forth in any preceding claim, wherein the phase (a) comprises aluminum oxide or yttriumoxide and the metal of the phase (b) is at least one element selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum and wolfram.
Claim 13
Dependent Claim
30 words
A high toughness ceramic as set forth in claim 9, wherein the phase (a) comprises yttrium oxide and the metallic element of the particle phase (b) is titanium and/or vanadium.
Claim 14
Dependent Claim
41 words
A high toughness ceramic as set forth in claim 12, wherein the phase (a) is present in an amount of 0.05 to 10% by volume and the particle phase (b) is present in an amount of 5 to 40% by volume.
Claim 15
Dependent Claim
111 words
A process for the preparation of a high toughness ceramic which comprises hot-pressing a mixture comprising (1) at least one metal selected from the group consisting of aluminum, scandium, yttrium and rare earth elements or a hydride, carbide, nitride, silicide or oxide thereof, (2) at least one metal selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum and wolfram or a hydride, carbide, nitride, silicide or oxide thereof having an average particle size of 5 to 100um and (3) a silicon carbide powder having an average particle size of 0.1 to 2um, at a temperature of 1900 to 2300°C either under vacuum or in an inert gas atmosphere.
Claim 16
Dependent Claim
111 words
A process for the preparation of a high toughness ceramic which comprises hot-pressing a mixture comprising (1) at least one metal selected from the group consisting of aluminum, scandium, yttrium and rare earth elements or a hydride, carbide, nitride, silicide or oxide thereof, (2) at least one metal selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum and wolfram or a hydride, carbide, nitride, silicide or oxide thereof having an average particle size of 5 to 100um and (3) a silicon carbide powder having an average particle size of 0.1 to 2um, at a temperature of 1900 to 2300°C either under vacuum or in an inert gas atmosphere.
Claim 17
Dependent Claim
46 words
A process for the preparation of a high toughness ceramic as set forth in claim 14, which comprises adding metallic yttrium and metallic titanium or/and metallic vanadium to the silicon carbide, hot-pressing the obtained mixture at 2000 to 2200°C and immediately and slowly cooling the mixture.
References Cited (Backward Citations)
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