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US4690909A
Expired / Lapsed
US
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Silicon carbide-graphite composite material and process for producing same
Assignee: Niterra Co Ltd
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Filing: 1986-05-06
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Granted: 1987-09-01
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Expires: 2006-05-06
Abstract
Abstract A silicon carbide-graphite composite material is disclosed. The composite material includes graphite as a secondary phase which are dispersed uniformly in a grain boundary of the silicon carbide. The graphite have an average grain size of not more than 3 μm and are present in a proportion of 1 to 20 vol % based on the volume of the silicon carbide. The composite material has a density greater than 90% of the theoretical density. A process for producing the silicon carbide-graphite composite material is also disclosed. The composite material is a high-density and high-strength material.
Inventors
- 👤 Akiyasu Okuno
- 👤 Masakazu Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:38
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/16; F16J15/34; F16J15/3496; C; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
135 words
A process for producing a silicon carbide-graphite composite material, comprising: adding a sintering aid to silicon carbide of an average grain size less than 1 μm, said sintering aid comprising 0.1 to 3.0 wt% of a compound selected from the group consisting of boron and a boron compound which includes a corresponding amount of boron; and 0.1 to 6.0 wt% of an organic carbonaceous compound which includes a corresponding amount of carbon each based on the weight of silicon carbide; further adding carbon black as a silicon carbide grain growth inhibitor to silicon carbide in an amount of 1 to 20 vol% based on the volume of the silicon carbide; blending the compositions into an intimate mixture; molding the intimate mixture to obtain a molded body; and sintering the molded body at about atmospheric pressure.
Claim 2
Dependent Claim
135 words
A process for producing a silicon carbide-graphite composite material, comprising: adding a sintering aid to silicon carbide of an average grain size less than 1 μm, said sintering aid comprising 0.1 to 3.0 wt% of a compound selected from the group consisting of boron and a boron compound which includes a corresponding amount of boron; and 0.1 to 6.0 wt% of an organic carbonaceous compound which includes a corresponding amount of carbon each based on the weight of silicon carbide; further adding carbon black as a silicon carbide grain growth inhibitor to silicon carbide in an amount of 1 to 20 vol% based on the volume of the silicon carbide; blending the compositions into an intimate mixture; molding the intimate mixture to obtain a molded body; and sintering the molded body at about atmospheric pressure.
Claim 3
Dependent Claim
16 words
A process as claimed in claim 1, wherein said molded body is sintered at atmospheric pressure.
Claim 4
Dependent Claim
16 words
A process as claimed in claim 1, wherein said organic carbonaceous compound is a phenolic resin.
Claim 5
Dependent Claim
32 words
A process as claimed in claim 1, wherein said organic carbonaceous compound is one which can supply carbon obtained by decomposition of an organic compound as a carbon component of sintering aids.
Claim 6
Dependent Claim
14 words
A process as claimed in claim 1, wherein said sintering aid contains the boron.
Claim 7
Dependent Claim
23 words
A process as claimed in claim 1, wherein said sintering aid contains the boron compound which includes a corresponding amount of of boron.
Claim 8
Dependent Claim
26 words
A process is claimed in claim 1, wherein the resultant composite material has great shock resistance and bending strength, and a reduced coefficient of kinetic friction.
Claim 9
Dependent Claim
16 words
A process is claimed in claim 1, wherein said carbon black converts to graphite during sintering.
Claim 10
Dependent Claim
19 words
A process as claimed in claim 7, wherein said graphite comprises a secondary phase of the resultant composite material.
Claim 11
Dependent Claim
36 words
A process is claimed in claim 9, wherein said graphite which comprises a secondary phase of the resultant composite material has a high heat resistance and does not impair the chemical stability of the silicon carbide.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-31 | 1991-03-02 | 1991-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-31 | 1995-03-02 | 1995-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-31 | 1999-03-02 | 1999-09-01 | $7700.00 | Window Closed / Lapsed |