Patent US3821036A successfully refreshed from Google Patents.
US3821036A
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Oxyreaction strengthening of metals
Assignee: United States Department of the Interior
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Filing: 1972-05-15
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Granted: 1974-06-28
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Expires: 1992-05-15
Abstract
Abstract Oxyreaction strengthening of base metals and their alloys is accomplished by a powder metallurgical technique in which a base metal powder containing oxygen is blended with a reactive metal powder, and then pressed, sintered, densified if desired, and held below the sintering temperature to form an ultrafine dispersion of reactive metal oxide throughout the base metal. Preferred base metals include the Periodic Table metals of Groups 1B, VIB, and VIII while preferred reactive metals include silicon, aluminum and Periodic Table elements of Group IVB.
Inventors
- 👤 M Copeland
- 👤 Brien W O
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:47
CPC Classifications
C; C22; C22C; C22C1/00; C22C1/10; C22C1/1078
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
18 words
The process of claim 1 wherein the sintered compact is further densified prior to the precipitation heat treatment.
Claim 2
Dependent Claim
22 words
The process of claim 1 wherein the base metal is chosen from the group consisting of tungsten and molybdenum and their alloys.
Claim 3
Dependent Claim
19 words
The process of claim 3 wherein the reactive metal is chosen from the group consisting of zirconium and hafnium.
Claim 4
Dependent Claim
23 words
The process of claim 4 wherein the oxygen content of the base metal is in the range of 0.05 to 0.5 weight percent.
Claim 5
Dependent Claim
26 words
The process of claim 5 wherein the base metal comprises tungsten and wherein the reactive metal is selected from the group consisting of zirconium and hafnium.
Claim 6
Dependent Claim
31 words
The process of claim 6 wherein the compact is sintered at a temperature in the range of 1,500* to 2,400*C for a time in the range of 1 to 24 hours.
Claim 7
Dependent Claim
48 words
The process of claim 7 wherein the sintered compact is densified and is thereafter subjected to a precipitation heat treatment at a temperature within the range of about 1,400* to 2, 000*C but below the sintering temperature for a time in the range of 2 to 24 hours.
Claim 8
Dependent Claim
44 words
The process of claim 7 wherein the sintered compact is densified and formed into a useful shape and is thereafter subjected to a precipitation heat treatment comprising normal use at a temperature within the range of 1,400* to 2,000*C but below the sintering temperature.
Claim 9
Dependent Claim
20 words
The process of claim 7 wherein the reactive metal is in the form of an intermetallic reactive metal-base metal compound.
Claim 10
Dependent Claim
11 words
The process of claim 10 wherein the intermetallic compound is ZrW2.
Claim 11
Dependent Claim
11 words
The process of claim 10 wherein the intermetallic compound is HfW2.
Claim 12
Dependent Claim
36 words
The process of claim 11 wherein zirconium is blended with the tungsten base metal powder in an amount ranging from 125 to 300% of that required to completely react with the oxygen combined with the tungsten.
Claim 13
Dependent Claim
26 words
The process of claim 5 wherein the base metal comprises molybdenum and wherein the reactive metal is selected from the group consisting of zirconium and hafnium.
Claim 14
Dependent Claim
11 words
The process of claim 14 wherein the reactive metal is zirconium.
Claim 15
Dependent Claim
58 words
An oxyreaction strengthened ZOW alloy containing 0.4 to 0.5 weight percent zirconium and 800 to 1,000 ppm oxygen by weight, the balance comprising tungsten; substantially all of said oxygen being chemically combined with zirconium and dispersed throughout the tungsten in the form of very small oxide particles with the balance of the zirconium being dissolved in the tungsten.
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) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |