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US4487734A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the preparation of a high density sintered body of silicon carbide
Assignee: TDK Corp
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Filing: 1983-07-26
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Granted: 1984-12-11
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Expires: 2003-07-26
Abstract
Abstract A sintered body of silicon carbide having an outstandingly high density is readily obtained by sintering a shaped form of a powdery blend composed of a silicon carbide powder, an aluminum borate as a sintering aid and a carbonizable organic compound mixed together in a limited proportion.
Inventors
- 👤 Kentaro Sawamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:47
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
86 words
A method for the preparation of a high-density sintered body of silicon carbide which comprises admixing 100 parts by weight of a silicon carbide powder with from 0.1 to 20 parts by weight of an aluminum borate in a powdery form and a carbonizable organic compound in an amount capable of giving from 1 to 15 parts by weight of residual carbon after pyrolysis to give a powdery blend, shaping the powdery blend into a form and sintering the thus shaped form of the powdery blend.
Claim 2
Independent Claim
86 words
A method for the preparation of a high-density sintered body of silicon carbide which comprises admixing 100 parts by weight of a silicon carbide powder with from 0.1 to 20 parts by weight of an aluminum borate in a powdery form and a carbonizable organic compound in an amount capable of giving from 1 to 15 parts by weight of residual carbon after pyrolysis to give a powdery blend, shaping the powdery blend into a form and sintering the thus shaped form of the powdery blend.
Claim 3
Dependent Claim
21 words
The method as claimed in claim 1 wherein the silicon carbide powder has an average particle diameter not exceeding 20 μm.
Claim 4
Dependent Claim
20 words
The method as claimed in claim 1 wherein the aluminum borate has an average particle diameter not exceeding 20 μm.
Claim 5
Dependent Claim
32 words
The method as claimed in claim 1 wherein the carbonizable organic compound is selected from the group consisting of liquid and solid phenolic resins, coal tar pitches, petroleum pitches and heavy oils.
Claim 6
Dependent Claim
34 words
The method as claimed in claim 1 wherein the shaping of the powdery blend into a form is performed by compression under a pressure in the range from 200 to 2000 kg/cm 2 .
Claim 7
Dependent Claim
32 words
The method as claimed in claim 1 wherein the sintering of the shaped form is performed at a temperature in the range from 1700° to 2300° C. for 10 to 60 minutes.
Claim 8
Dependent Claim
27 words
The method as claimed in claim 1 wherein the sintering of the shaped form is performed in an atmosphere of an inert gas or a reducing gas.
Claim 9
Dependent Claim
66 words
A high-density sintered body of silicon carbide prepared by sintering a shaped form of a powdery blend composed of 100 parts by weight of a silicon carbide powder, from 0.1 to 20 parts by weight of an aluminum borate in a powdery form and a carbonizable organic compound in an amount capable of giving from 1 to 15 parts by weight of residual carbon after pyrolysis.
Claim 10
Dependent Claim
66 words
A high-density sintered body of silicon carbide prepared by sintering a shaped form of a powdery blend composed of 100 parts by weight of a silicon carbide powder, from 0.1 to 20 parts by weight of an aluminum borate in a powdery form and a carbonizable organic compound in an amount capable of giving from 1 to 15 parts by weight of residual carbon after pyrolysis.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-11 | 1988-06-11 | 1988-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-11 | 1992-06-11 | 1992-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-11 | 1996-06-11 | 1996-12-11 | $7700.00 | Window Closed / Lapsed |