EP0174153A1
Expired / Lapsed
EP
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A silicon nitride sintered body and method of producing the same
Assignee: NGK Insulators Ltd
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Filing: 1985-08-28
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Granted: —
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Expires: 2005-08-28
Abstract
Abstract A highly dense Si 3 N. sintered body having a substantially crystalline intergranular phase X, which has an improved mehcanical strength at high temperatures and excellent static fatigue properties, making it particularly useful for high temperature structural components or parts, is produced by sintering a molded body of a blend comprising Si 3 N 4 , Y-, Mg-and Ce-compounds. The amounts used by weight are Si 3 N 4 75-95%, Y 2-15% as Y 2 O 3 , Mg 1-10% as MgO and Ce 1-10% as CeO.
Inventors
- 👤 Minoru Matsui
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 00:33
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
75 words
A silicon nitride sintered body consisting mainly of Si 3 N 4 and containing Y, Mg and Ce, wherein the content of Si 3 N 4 is 75-95% by weight, the content of Y is 2-15% by weight as Y 2 0 3 , the content of Mg is 1-10% by weight as MgO and the content of Ce is 1-10% by weight as Ce0 2 , based on the weight of the sintered body.
Claim 2
Dependent Claim
75 words
A silicon nitride sintered body consisting mainly of Si 3 N 4 and containing Y, Mg and Ce, wherein the content of Si 3 N 4 is 75-95% by weight, the content of Y is 2-15% by weight as Y 2 0 3 , the content of Mg is 1-10% by weight as MgO and the content of Ce is 1-10% by weight as Ce0 2 , based on the weight of the sintered body.
Claim 3
Dependent Claim
16 words
A silicon nitride sintered body as claimed in claim 1, having a substantially crystalline intergranular phase.
Claim 4
Independent Claim
77 words
A method of producing a silicon nitride sintered body, which comprises molding a powdery mixture of 75-95% by weight of silicon nitride starting powder and Y-, Mg- and Ce-compounds as a sintering aid in amount of 2-15% by weight as Y 2 0 3 , 1-10% by weight as MgO and 1-10% by weight as Ce0 2 , and then sintering the resulting molded body at a temperature of 1,650-1,800°C in a nitrogen or inert gas atmosphere.
Claim 5
Independent Claim
77 words
A method of producing a silicon nitride sintered body, which comprises molding a powdery mixture of 75-95% by weight of silicon nitride starting powder and Y-, Mg- and Ce-compounds as a sintering aid in amount of 2-15% by weight as Y 2 0 3 , 1-10% by weight as MgO and 1-10% by weight as Ce0 2 , and then sintering the resulting molded body at a temperature of 1,650-1,800°C in a nitrogen or inert gas atmosphere.
Claim 6
Dependent Claim
25 words
A method as claimed in claim 3, wherein said Y-, Mg- and Ce-compounds are Y 2 0 3 , MgO and CeO 2 , respectively.
Claim 7
Dependent Claim
18 words
A method according to claim 3 or claim 4 wherein pressureless sintering in a nitrogen atmosphere is used.
References Cited (Backward Citations)
DE2820694A1
Cited
EP0107919A1
Cited
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