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Patent US3816103A successfully refreshed from Google Patents.
US3816103A
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Method of deoxidizing and desulfurizing ferrous alloy with rare earth additions
Assignee: Bethlehem Steel Corp
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Filing: 1973-04-16
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Granted: 1974-06-11
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Expires: 1993-04-16
Abstract
Abstract A procedure for improving the through thickness properties of coarse grain ferrous alloy plate through a controlled deoxidizing and desulfurizing practice. Said practice includes adding rare earth additions to the tapping stream or ladle during tapping of the unkilled or non-deoxidized molten ferrous alloy. The ferrous alloy, when processed into plates, is characterized by a low sulfur content below about .015 percent, by weight, preferably less than about .010 percent, and by excellent ductility when tensile tested in any axial direction.
Inventors
- 👤 J Link
- 👤 G Marsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:22
CPC Classifications
C; C21; C21C; C21C7/00; C21C7/04; C21C7/06; C21C7/064
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
32 words
The process according to claim 1 wherein said molten metal bath is prepared in a furnace and that said additions are made to the molten ferrous alloy as it is transferred therefrom.
Claim 2
Dependent Claim
32 words
The process according to claim 1 wherein said rare earth metal is added as a 30-35 percent rare earth silicide iN an amount of between 9 to 15 lbs./ton of molten metal.
Claim 3
Dependent Claim
18 words
The process according to claim 1 wherein said maximum final sulfur content is less than about .010 percent.
Claim 4
Dependent Claim
63 words
The process according to claim 3 where there is an inverse relationship between the carbon content of the molten metal bath and the amount of rare earth silicide added thereto, including the step of making a preliminary determination of the carbon content of the said bath and adding only that amount of rare earth silicide needed to effect the desired deoxidation and desulfurization.
Claim 5
Dependent Claim
23 words
The process according to claim 2 wherein said molten ferrous alloy is transferred from said furnace at a temperature of about 2,900* F.
Claim 6
Dependent Claim
52 words
The process according to claim 2 wherein the initial carbon content is between about .10 to .19 percent, and that said additions are made in the following sequence: coal, a portion of the manganese addition, rare earth, balance of the manganese needed to achieve the predetermined final content, ferrosilicon and burnt lime.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |