US4820360A
Expired / Lapsed
US
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Method for developing ultrafine microstructures in titanium alloy castings
Assignee: United States Department of the Air Force
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Filing: 1987-12-04
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Granted: 1989-04-11
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Expires: 2007-12-04
Abstract
Abstract A method for improving the microstructure of cast titanium alloy articles which comprises the steps of hydrogenating the cast article at a temperature near or above the titanium-hydrogen eutectoid of 815 DEG C. (of about 780 DEG to 1020 DEG C.) to a hydrogen level of about 0.50 to 1.50 weight percent, cooling the thus-hydrogenated article to room temperature at a controlled rate, heating the thus-cooled, hydrogenated article to a temperature of about 650 DEG to 750 DEG C., applying a vacuum to dehydrogenate the article, and cooling the thus-dehydrogenated article at a controlled rate.
Inventors
- 👤 Daniel Eylon
- 👤 Francis H. Froes
- 👤 Charles F. Yolton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:28
CPC Classifications
C; C22; C22F; C22F1/00; C22F1/16; C22F1/18; C22F1/183
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
102 words
A method for improving the microstructure of cast titanium alloy articles which comprises the steps of hydrogenating the cast article at a temperature near or greater than the titanium-hydrogen eutectoid temperature of 815° C., said temperature of hydrogenation being in the range of about 780° to 1020° C. to a hydrogen level of about 0.50 to 1.50 weight percent, cooling the thus-hydrogenated article to room temperature at a controlled rate, heating the thus-cooled, hydrogenated article to a temperature of about 650° to 750° C., applying a vacuum to dehydrogenate the article and cooling said article to room temperature at a controlled rate.
Claim 2
Independent Claim
102 words
A method for improving the microstructure of cast titanium alloy articles which comprises the steps of hydrogenating the cast article at a temperature near or greater than the titanium-hydrogen eutectoid temperature of 815° C., said temperature of hydrogenation being in the range of about 780° to 1020° C. to a hydrogen level of about 0.50 to 1.50 weight percent, cooling the thus-hydrogenated article to room temperature at a controlled rate, heating the thus-cooled, hydrogenated article to a temperature of about 650° to 750° C., applying a vacuum to dehydrogenate the article and cooling said article to room temperature at a controlled rate.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein said controlled cooling rate is about 5° to 40° C. per minute.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said article is made of Ti-6Al -4V alloy.
Claim 5
Dependent Claim
42 words
The method of claim 3 wherein said hydrogenation is carried out at a temperature of about 1450° F. (787° C.) to a hydrogen level of about 1.0 wt. percent and wherein said dehydrogenation is carried out at about 1300° F. (704° C.).
Claim 6
Dependent Claim
42 words
The method of claim 3 wherein said hydrogenation is carried out at a temperature of about 1650° F. (899° C.) to a hydrogen level of about 0.76 wt. percent and wherein said dehydrogenation is carried out at about 1300° F. (704° C.).
Claim 7
Dependent Claim
42 words
The method of claim 3 wherein said hydrogenation is carried out at a temperature of about 1850° F. (1010° C.) to a hydrogen level of about 0.77 wt. percent and wherein said dehydrogenation is carried out at about 1300° F. (704° C.).
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1992-04-10 | 1992-10-10 | 1993-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-10 | 1996-10-10 | 1997-04-11 | $3760.00 | Window Closed / Lapsed |
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