US4049470A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refining nickel base superalloys
Assignee: ALLEGHENY INTERNATIONAL ACCEPTANCE Corp
•
Filing: 1976-04-29
•
Granted: 1977-09-20
•
Expires: 1996-04-29
Abstract
Abstract A process for producing a low iron nickel base superalloy having a very low selenium content. The process includes the steps of: preparing a superalloy melt containing, by weight, at least 60% nickel, no more than 1% iron, and more than 0.0004% selenium; maintaining the melt in contact with a calcium and/or magnesium bearing substance for a period of time sufficient to allow for reaction between selenium and calcium and/or magnesium, and a lowering of said melt's selenium content to a level below 0.0003%, said selenium removal being carried out in a substantially oxygen free atmosphere; casting the melt; and heat treating the cast metal.
Inventors
- 👤 Claudia J. Burton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:57
CPC Classifications
C; C22; C22C; C22C1/00; C22C1/02; C22C1/023
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
132 words
In a process for producing a low iron, nickel base superalloy, which process includes the steps of preparing a superalloy melt containing, by weight, at least 60% nickel, no more than 1% iron, and more than 0.0004% selenium; casting said melt; and heat treating the cast metal; the improvement comprising the steps of maintaining said melt in contact with a calcium and/or magnesium bearing substance for a period of time sufficient to allow for reaction between selenium, and calcium and/or magnesium, and a lowering of said melt's selenium content to a level below 0.0003%, said selenium removal being carried out in a substantially oxygen free atmosphere, said reacted selenium accumulating as slag on the surface of said melt, said selenium-bearing slag being separated from said melt prior to solidification of said melt.
Claim 2
Dependent Claim
132 words
In a process for producing a low iron, nickel base superalloy, which process includes the steps of preparing a superalloy melt containing, by weight, at least 60% nickel, no more than 1% iron, and more than 0.0004% selenium; casting said melt; and heat treating the cast metal; the improvement comprising the steps of maintaining said melt in contact with a calcium and/or magnesium bearing substance for a period of time sufficient to allow for reaction between selenium, and calcium and/or magnesium, and a lowering of said melt's selenium content to a level below 0.0003%, said selenium removal being carried out in a substantially oxygen free atmosphere, said reacted selenium accumulating as slag on the surface of said melt, said selenium-bearing slag being separated from said melt prior to solidification of said melt.
Claim 3
Dependent Claim
22 words
An improvement according to claim 1, including the step of filtering said melt to reduce the possibility of contaminating said resultant superalloy.
Claim 4
Dependent Claim
37 words
An improvement according to claim 1, wherein said melt is maintained in contact with said calcium and/or magnesium bearing substance for a period of time sufficient to lower said melts selenium content to a level below 0.0002%.
Claim 5
Dependent Claim
18 words
An improvement according to claim 1, wherein said melt is maintained in contact with a calcium bearing substance.
Claim 6
Dependent Claim
20 words
An improvement according to claim 4, wherein said calcium bearing substance is from the group consisting of CaO and CaNi.
Claim 7
Dependent Claim
15 words
An improvement according to claim 1, wherein said nickel in said melt is electrolytic nickel.
References Cited (Backward Citations)
US3853540A
Cited
US3891425A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-19 | 1981-03-21 | 1981-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-19 | 1985-03-21 | 1985-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-19 | 1989-03-21 | 1989-09-20 | $7700.00 | Window Closed / Lapsed |