US3736650A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making metal-to-ceramic seals
Assignee: Varian Medical Systems Inc
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Filing: 1971-06-01
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Granted: 1973-06-05
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Expires: 1991-06-01
Abstract
Abstract An alkali metal corrosion resistant vacuum tight metal-toceramic seal is formed between a high alumina ceramic body and a refractory alkali metal resistant metal member, such as Cb-1Zr, by interposing a powdered brazing mixture comprising by weight a majority of elemental columbium powder and a second metal powder selected from the class consisting of iron and nickel, and firing the assembly in vacuum at a temperature between 1,500*C and 1,675*C to partially melt a portion of the powder to form a melted bonding phase component interstitially of the undissolved columbium particles for bonding the ceramic to the metal part.
Inventors
- 👤 N Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:09
CPC Classifications
C; C04; C04B; C04B37/00; C04B37/02; C04B37/023; C04B37/026; B; B23; B23K; B23K35/00; B23K35/02; B23K35/0222; B23K35/0244; C04B2237/00; C04B2237/02; C04B2237/12; C04B2237/122; C04B2237/30; C04B2237/32; C04B2237/34; C04B2237/343; C04B2237/40; C04B2237/403; C04B2237/50; C04B2237/70; C04B2237/708; C04B2237/72
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
23 words
The method of claim 1 wherein said ceramic body is selected from the class consisting of alumina, pore free translucent alumina, and sapphire.
Claim 2
Dependent Claim
15 words
The method of claim 1 wherein the firing temperature range is between 1500*C and 1675*C.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein the second powder comprises iron in the amount of approximately 17 percenT by weight of the powdered mixture.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein the second powder comprises nickel in the amount of approximately 15 percent by weight of the powdered mixture.
Claim 5
Dependent Claim
148 words
In a method for brazing a metallic member to a ceramic body the steps of, interposing a powdered mixture between the ceramic body and the metal member, said powdered mixture consisting essentially of by weight a majority of columbium powder and a second metal powder selected from the class consisting of iron and nickel, urging the coated ceramic body and metal member into intimate contact with the powdered mixture, and firing the ceramic body, metal member and mixture at a temperature sufficiently high to produce only partial melting of the powder mixture such that upon cooling a solidified bonding phase component is formed interstitially of the undissolved columbium particles for bonding the undissolved columbium particles to the ceramic body and the metal member, whereby the undissolved columbium particles from a ductile metal layer bonded between the metal member and the ceramic body via the solidified bonding phase component.
Claim 6
Dependent Claim
25 words
The method of claim 6 wherein the metal member is selected from the cass consisting of class tantalum, tantalum alloys, molybdenum, columbium, and columbium alloys.
Claim 7
Dependent Claim
11 words
The method of claim 7 wherein the metal member is Cb-1Zr.
Claim 8
Dependent Claim
23 words
The method of claim 6 wherein said ceramic body is selected from the class consisting of alumina, pore free translucent alumina, and sapphire.
Claim 9
Dependent Claim
15 words
The method of claim 6 wherein the firing temperature range is between 1500*C and 1675*C.
Claim 10
Dependent Claim
23 words
The method of claim 6 wherein the second powder comprises iron in the amount of approximately 17 percent weight of the powdered mixture.
Claim 11
Dependent Claim
24 words
The method of claim 6 wherein the second powder comprises nickel in the amount of approximately 15 percent by weight of the powdered mixture.
Claim 12
Dependent Claim
27 words
The method of claim 1 wherein said ceramic body is metallized with tungsten or molybdenum prior to said step of coating said body with said powdered mixture.
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) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |