US4502884A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing fiber-shaped tantalum powder and the powder produced thereby
Assignee: Cabot Corp
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Filing: 1983-10-27
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Granted: 1985-03-05
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Expires: 2003-10-27
Abstract
Abstract A method for producing fiber-shaped tantalum powder by deforming a composite of tantalum powder and an auxiliary metal, and the powder produced thereby.
Inventors
- 👤 James A. Fife
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:11
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/004; H01G9/04; H01G9/042; B; B22; B22F; B22F1/00; B22F1/06; B22F1/062; B22F9/00; B22F9/16; H01G9/048; H01G9/052; H01G9/0525; Y; Y10; Y10S; Y10S75/00; Y10S75/952
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
84 words
A method for producing fiber-shaped powder from suitable metals of Groups IV, V, VI of the Periodic Table comprising: forming a composite of said metal powder particles and an auxiliary metal by powder metallurgical techniques, working said metal/auxiliary metal composite by mechanical deformation until said metal particles are deformed into fiber shapes within a matrix of the auxiliary metal, removing said auxiliary metal from said matrix by treatment with a mineral acid suitable to dissolve the auxiliary metal, and recovering the fiber-shaped metal powder.
Claim 2
Independent Claim
84 words
A method for producing fiber-shaped powder from suitable metals of Groups IV, V, VI of the Periodic Table comprising: forming a composite of said metal powder particles and an auxiliary metal by powder metallurgical techniques, working said metal/auxiliary metal composite by mechanical deformation until said metal particles are deformed into fiber shapes within a matrix of the auxiliary metal, removing said auxiliary metal from said matrix by treatment with a mineral acid suitable to dissolve the auxiliary metal, and recovering the fiber-shaped metal powder.
Claim 3
Dependent Claim
27 words
The method of claim 1 comprising forming a composite of tantalum powder particles and an auxiliary metal by admixing said tantalum particles with an auxiliary metal powder.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein said auxiliary metal is copper.
Claim 5
Dependent Claim
32 words
The method of claim 1 wherein the auxiliary metal is dissolved by treatment with a mineral acid selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, and combinations thereof.
Claim 6
Dependent Claim
32 words
The method of claim 1 wherein the diameter of the tantalum particles in the tantalum/auxiliary metal composite is no more than about five times the diameter of the fiber-shaped tantalum powder product.
Claim 7
Dependent Claim
12 words
The fiber-shaped metal powder produced according to the method of claim 1.
Claim 8
Dependent Claim
15 words
The fiber-shaped tantalum powder of claim 6 having a diameter less than about 10 μm.
Claim 9
Dependent Claim
16 words
The fiber-shaped tantalum powder of claim 7 having a diameter between about 0.5 and 3 μm.
Claim 10
Dependent Claim
15 words
The fiber-shaped tantalum powder of claim 6 having a length less than about 100 μm.
Claim 11
Dependent Claim
17 words
The fiber-shaped tantalum powder of claim 9 having a length less between about 20 and 50 μm.
References Cited (Backward Citations)
US3827865A
Cited
DE3111418A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-04 | 1988-09-03 | 1989-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-04 | 1992-09-03 | 1993-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-04 | 1996-09-03 | 1997-03-05 | $7700.00 | Window Closed / Lapsed |