US4501717A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sintering method using a plasma gas atmosphere
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1983-07-21
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Granted: 1985-02-26
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Expires: 2003-07-21
Abstract
Abstract This invention provides a process for producing a high quality powdered alloy such as cemented carbides, cermets, ceramics and iron-containing sintered alloys by sintering, characterized in that the sintering is carried out in a plasma gas atmosphere of H2, N2, CO, He and/or Ar.
Inventors
- 👤 Shinya Tsukamoto
- 👤 Kunihiro Takahashi
- 👤 Akira Doi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:59
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/10; B22F3/105; C; C04; C04B; C04B35/00; C04B35/622; C04B35/64
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
75 words
In a method which comprises sintering a pressed body of a powder selected from the group consisting of powders to produce cemented carbides, cermets, ceramics and ferrous sintered bodies, the improvement in which a part or all of the sintering process is carried out in a plasma gas atmosphere selected from the group consisting of H 2 , N 2 , Co, He, Ar and mixtures thereof under a pressure of 0.1 to 50 Torr.
Claim 2
Dependent Claim
75 words
In a method which comprises sintering a pressed body of a powder selected from the group consisting of powders to produce cemented carbides, cermets, ceramics and ferrous sintered bodies, the improvement in which a part or all of the sintering process is carried out in a plasma gas atmosphere selected from the group consisting of H 2 , N 2 , Co, He, Ar and mixtures thereof under a pressure of 0.1 to 50 Torr.
Claim 3
Dependent Claim
22 words
A method according to claim 1 wherein the plasma gas is a low temperature plasma generated by a high frequency power source.
Claim 4
Dependent Claim
20 words
A method according to claim 1 wherein the plasma is a low temperature plasma generated by a microwave power source.
Claim 5
Dependent Claim
17 words
A method according to claim 1 wherein the sintering is carried out at 1000° to 1500° C.
Claim 6
Dependent Claim
14 words
A method according to claim 1 wherein the sintered body is a cemented carbide.
Claim 7
Dependent Claim
13 words
A method according to claim 1 wherein the sintered body is a cermet.
Claim 8
Dependent Claim
13 words
A method according to claim 1 wherein the sintered body is a ceramic.
Claim 9
Dependent Claim
15 words
A method according to claim 1 wherein the sintered body is a ferrous sintered body.
Claim 10
Dependent Claim
15 words
A method according to claim 1 in which the plasma gas is H 2 .
Claim 11
Dependent Claim
15 words
A method according to claim 1 in which the plasma gas is N 2 .
Claim 12
Dependent Claim
13 words
A method according to claim 1 in which the plasma gas is CO.
Claim 13
Dependent Claim
19 words
A method according to claim 1 in which the plasma gas is a mixture of H 2 and CO.
Claim 14
Dependent Claim
23 words
A method according to claim 1 in which the plasma gas is a mixture of H 2 , CO and N 2 .
Claim 15
Dependent Claim
25 words
A method according to claim 1 in which the plasma gas is a mixture of H 2 , N 2 , CO, He and Ar.
References Cited (Backward Citations)
DE692461C
Cited
SU420394A1
Cited
US4347084A
Cited
US4011076A
Cited
JPS5450407A
Cited
JPS54122611A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-26 | 1988-08-27 | 1989-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-26 | 1992-08-27 | 1993-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-26 | 1996-08-27 | 1997-02-26 | $7700.00 | Window Closed / Lapsed |