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US4722756A
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Method for deoxidizing tantalum material
Assignee: Cabot Corp
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Filing: 1987-02-27
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Granted: 1988-02-02
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Expires: 2007-02-27
Abstract
Abstract Disclosed is a process for the reduction of oxygen content in tantalum and/or columbium-containing material comprising heating the material under a hydrogen atmosphere in the presence of an oxygen-active metal.
Inventors
- 👤 Robert A. Hard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:18
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/004; H01G9/04; H01G9/048; H01G9/052; B; B22; B22F; B22F1/00; B22F1/14; B22F1/145; B22F9/00; B22F9/02; B22F9/023; C; C22; C22B; C22B34/00; C22B34/20; C22B34/24; C22B5/00; C22B5/02; C22B5/04; C22B9/00; C22B9/006; C22B9/05
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
69 words
A process for the reduction of oxygen content in tantalum and/or columbium material comprising heating said material at a temperature ranging from about 900° to about 2400° C. (about 1173° to about 2673° K.) under a hydrogen-containing atmosphere in the presence of an oxygen-active metal selected from the group consisting of beryllium, calcium, cerium, hafnium, lathanum, lithium, praseodymium, scandium, thorium, titanium, uranium, vanadium, yttrium, zirconium, alloys and mixtures thereof.
Claim 2
Dependent Claim
69 words
A process for the reduction of oxygen content in tantalum and/or columbium material comprising heating said material at a temperature ranging from about 900° to about 2400° C. (about 1173° to about 2673° K.) under a hydrogen-containing atmosphere in the presence of an oxygen-active metal selected from the group consisting of beryllium, calcium, cerium, hafnium, lathanum, lithium, praseodymium, scandium, thorium, titanium, uranium, vanadium, yttrium, zirconium, alloys and mixtures thereof.
Claim 3
Dependent Claim
30 words
The process of claim 1 wherein the tantalum and/or columbium material is heated at a temperature ranging from about 1100° to about 2000° C. (about 1373° to about 2273° K.).
Claim 4
Dependent Claim
15 words
The process of claim 1 wherein the oxygen-active metal is titanium, zirconium, or mixtures thereof.
Claim 5
Dependent Claim
13 words
The process of claim 1 wherein the tantalum material is a tantalum powder.
Claim 6
Dependent Claim
28 words
The process of claim 4 wherein the tantalum powder is heated at a temperature ranging from about 1250° to about 1450° C. (about 1523° to about 1723° K.).
Claim 7
Dependent Claim
16 words
The process of claim 1 wherein the tantalum material is in the form of tantalum anodes.
Claim 8
Dependent Claim
22 words
The process of claim 6 wherein the tantalum anodes are heated at a temperature ranging from about 1300° to about 1550° C.
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) | 1991-02-01 | 1991-08-03 | 1992-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-01 | 1995-08-03 | 1996-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-01 | 1999-08-03 | 2000-02-02 | $7700.00 | Window Closed / Lapsed |