Patent EP0202899A2 successfully refreshed from Google Patents.
EP0202899A2
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A Silicon nitride sintered body and a method of producing the same
Assignee: NGK Insulators Ltd
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Filing: 1986-05-19
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Granted: —
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Expires: 2006-05-19
Abstract
Abstract A high density silicon nitride sintered body having a substantially crystallized intergranular phase and an improved mechanical strength at high temperature is produced by firing a molded body of a blend comprising Si 3 N 4 , a sintering aid and a crystallization controlling agent selected from at least one compound of Cr, Mn, Co, Ni, Nb and Mo with a specified blending ratio.
Inventors
- 👤 Minoru Matsui
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 14:26
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/593; C04B35/5935
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
39 words
A silicon nitride sintered body consisting mainly of SigN4 and a sintering aid and containing at least one compound of Cr, Mn, Co, Ni, Nb and Mo as a crystallization controlling agent and having a substantially crystallized intergranular phase.
Claim 2
Dependent Claim
39 words
A silicon nitride sintered body consisting mainly of SigN4 and a sintering aid and containing at least one compound of Cr, Mn, Co, Ni, Nb and Mo as a crystallization controlling agent and having a substantially crystallized intergranular phase.
Claim 3
Dependent Claim
51 words
The silicon nitride sintered body according to claim 1, wherein said at least one compound of Cr, Mn, Co, Ni, Nb and Mo is included in an amount of 0.05-3% by weight in total as Cr 2 0 3 , MnO, CoO, NiO, Nb 2 O 5 and MoO 3 .
Claim 4
Dependent Claim
28 words
The silicon nitride sintered body according to claim 1, wherein said sintering aid is at least one compound of Mg, Sr, Sc, Y, Zr, lanthanide element and Al.
Claim 5
Dependent Claim
19 words
The silicon nitride sintered body according to claim 3, wherein said sintering aid is compounds of Y and Mg.
Claim 6
Dependent Claim
20 words
The silicon nitride sintered body according to claim 3, wherein said sintering aid is compounds of Y, Mg and Ce.
Claim 7
Dependent Claim
40 words
The silicon nitride sintered body according to claim 5, wherein said sintering aid contains 2-15% by weight as Y 2 0 3 of Y-compound, 1-10% by weight as MgO of Mg-compound and 1-10% by weight as Ce0 2 of Ce-compound.
Claim 8
Independent Claim
48 words
A method of producing a silicon nitride sintered body, which comprises molding a blended powder of Si 3 N 4 with a sintering aid and at least one compound of Cr, Mn, Co, Ni, Nb and MO as a crystallization controlling agent, and firing or pressure sintering it.
Claim 9
Independent Claim
48 words
A method of producing a silicon nitride sintered body, which comprises molding a blended powder of Si 3 N 4 with a sintering aid and at least one compound of Cr, Mn, Co, Ni, Nb and MO as a crystallization controlling agent, and firing or pressure sintering it.
Claim 10
Dependent Claim
51 words
The method according to claim 7, wherein said at least one compound of Cr, Mn, Co, Ni, Nb and Mo is included in an amount of 0.05-3% by weight in total as Cr 2 O 3 , MnO , CoO , N i O , Nb 2 0 s and MoO3.
Claim 11
Dependent Claim
25 words
The method according to claim 8, wherein said sintering aid is at least one compound of Mg, Sr, Sc, Y, Zr, lanthanide element and A1.
Claim 12
Dependent Claim
16 words
The method according to claim 9, wherein said sintering aid is compounds of Y and Mg.
Claim 13
Dependent Claim
98 words
The method according to claim 9, wherein Si 3 N 4 is blended with 2-15% by weight as Y 2 0 3 of Y-compound, 1-10% by weight as MgO of Mg-compound and 1-10% by weight as Ce0 2 of Ce-compound as a sintering aid and 0.05-3% by weight in total as Cr 2 0 3 , MnO, CoO, NiO, Nb 2 0 5 or MoO 3 of at least one compound of Cr, Mn, Ni, Nb and Mo as a crystallization controlling agent, and the resulting blend is molded and fired in a nitrogen or inert gas atmosphere.
References Cited (Backward Citations)
No citation records indexed.
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