US4690909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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 09:54
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)
US3836673A
Cited
US4004934A
Cited
US3966855A
Cited
US4041117A
Cited
US4295890A
Cited
US4230497A
Cited
US4336216A
Cited
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 |