Patent US3758746A successfully refreshed from Google Patents.
US3758746A
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Hafnium electrode with inclusion used in an active medium
Assignee: Individual
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Filing: 1969-12-23
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Granted: 1973-09-11
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Expires: 1989-12-23
Abstract
Abstract An object of the present invention is to provide a cathode for electric arc processes in active media which is based on hafnium and comprises additions selected from a group comprising rare earths, alkali metals and alkaline earth metals and their oxides as well as transition elements of the IV, V, VI and VIII groups of the D. I. Mendeleev Table taken separately or in a combination.
Inventors
- 👤 D Bykhovsky
- 👤 A Medvedev
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:20
CPC Classifications
H; H05; H05H; H05H1/00; H05H1/24; H05H1/26; H05H1/32; H05H1/34; B; B23; B23K; B23K35/00; B23K35/22; B23K35/222; H05H1/3442
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
101 words
A cathode operating in an electric arc process in an active medium, said cathode being formed of a composition consisting essentially of hafnium and at least one addition which is a metal selected from the group consisting of rare earth metals, lithium, magnesium, barium, niobium, tantalum, molybdenum, tungsten and rhenium or a metal oxide selected from the group consisting of alkali metal oxides, alkaline earth metal oxides and rare earth metal oxides, said cathode forming on its working surface during operation thereof a film comprising hafnium, at least one of said additions and at least one component of said active medium.
Claim 2
Dependent Claim
24 words
A cathode according to claim 2 in which a rare earth metal is present in the amount of 0.2 to 10.0 percent by weight.
Claim 3
Dependent Claim
21 words
A cathode according to claim 3, in which lanthanum is present in the amount of 0.2 to 3.0 percent by weight.
Claim 4
Dependent Claim
27 words
A cathode according to claim 2 in which an oxide of a rare earth metal is present in the amount of 0.1 to 3.0 percent by weight.
Claim 5
Dependent Claim
22 words
A cathode according to claim 5, in which lanthanum oxide is present in the amount of 0.1 to 3.0 percent by weight.
Claim 6
Dependent Claim
21 words
A cathode according to claim 2, in which lithium is taken in the amount of 0.05 to 0.5 percent by weight.
Claim 7
Dependent Claim
21 words
A cathode according to claim 2, in which magnesium is taken in the amount of 0.1 to 1.0 percent by weight.
Claim 8
Dependent Claim
21 words
A cathode according to claim 2, in which barium is taken in the amount of 0.05 to 0.5 percent by weight.
Claim 9
Dependent Claim
29 words
A cathode according to claim 2 in which the alkali metal oxide or alkaline earth metal oxide is present in the amount of 0.5 to 3.0 percent by weight.
Claim 10
Dependent Claim
21 words
A cathode according to claim 2, in which thorium is present in the amount of 0.1 to 3.0 percent by weight.
Claim 11
Dependent Claim
21 words
A cathode according to claim 2, in which niobium is present in the amount of 1.0 to 10.0 percent by weight.
Claim 12
Dependent Claim
21 words
A cathode according to claim 2, in which tantalum is present in the amount of 1.0 to 30.0 percent by weight.
Claim 13
Dependent Claim
21 words
A cathode according to claim 2, in which molybdenum is present in the amount of 0.3 to 2.5 percent by weight.
Claim 14
Dependent Claim
21 words
A cathode according to claim 2, in which tungsten is present in the amount of 0.5 to 15.0 percent by weight.
Claim 15
Dependent Claim
21 words
A cathode according to claim 2, in which rhenium is present in the amount of 0.5 to 20.0 percent by weight.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-10 | 1977-03-12 | 1977-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-10 | 1981-03-12 | 1981-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-10 | 1985-03-12 | 1985-09-11 | $7700.00 | Window Closed / Lapsed |