Patent US4169722A successfully refreshed from Google Patents.
US4169722A
Expired / Lapsed
US
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Aluminothermic process
Assignee: Atomic Energy Board
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Filing: 1977-08-18
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Granted: 1979-10-02
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Expires: 1997-08-18
Abstract
Abstract A method of conducting an aluminothermic reduction of an oxide of a reactive metal comprising melting in a vessel in an induction furnace a conductive susceptor metal and thereafter adding the required intimately mixed reactants to the molten mass in the container wherein the rate of addition of the reactants and the power input to the induction furnace are controlled to maintain the temperature of the molten mass above a predetermined minimum.
Inventors
- 👤 George W. Fletcher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:02
CPC Classifications
C; C22; C22B; C22B5/00; C22B5/02; C22B5/04
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
149 words
A method of conducting an aluminothermic reduction of an oxide of a reactive metal selected from the group consisting of titanium and zirconium, comprising melting in a vessel in an induction furnace a conductive aluminum containing susceptor metal, adding said oxide and aluminum to the molten mass in the vessel wherein the rate of addition of the reactants and the power input to the induction furnace are controlled for maintaining the temperature of the molten mass above the melting point thereof, wherein the minimum total amount of aluminum added relative to the reactive metal is the theoretical amount necessary for effecting reduction of the oxide plus an amount equivalent to an atomic ratio of reactive metal to aluminum of 1:1 in the case of titanium and 1:2 in the case of zirconium, and thereafter allowing the reaction mixture to cool and separating the resultant alloy product from the slag.
Claim 2
Independent Claim
149 words
A method of conducting an aluminothermic reduction of an oxide of a reactive metal selected from the group consisting of titanium and zirconium, comprising melting in a vessel in an induction furnace a conductive aluminum containing susceptor metal, adding said oxide and aluminum to the molten mass in the vessel wherein the rate of addition of the reactants and the power input to the induction furnace are controlled for maintaining the temperature of the molten mass above the melting point thereof, wherein the minimum total amount of aluminum added relative to the reactive metal is the theoretical amount necessary for effecting reduction of the oxide plus an amount equivalent to an atomic ratio of reactive metal to aluminum of 1:1 in the case of titanium and 1:2 in the case of zirconium, and thereafter allowing the reaction mixture to cool and separating the resultant alloy product from the slag.
Claim 3
Dependent Claim
21 words
A method as claimed in claim 1 in which the reactants are pelletized prior to addition to the molten susceptor metal.
Claim 4
Dependent Claim
22 words
A method as claimed in claim 1 in which the susceptor metal is an alloy obtained by a previous similar aluminothermic reduction.
Claim 5
Dependent Claim
27 words
A method as claimed in claim 1 in which the mixed reactants comprise finely subdivided oxide ore of a reactive metal, aluminum powder and a slagging agent.
Claim 6
Dependent Claim
17 words
A method as claimed in claim 4 in which calcium oxide is added as a slagging agent.
Claim 7
Dependent Claim
18 words
A method as claimed in claim 1 in which the reduction is carried out under an inert atmosphere.
Claim 8
Dependent Claim
25 words
A method as claimed in claim 1 in which the reactive metal is recovered from the resultant alloy by evaporating the aluminum under reduced pressure.
Claim 9
Dependent Claim
18 words
A method as claimed in claim 7 in which the evaporation is effected in an electron beam furnace.
Claim 10
Dependent Claim
12 words
A reactive metal produced by a method as claimed in claim 1.
Claim 11
Dependent Claim
15 words
A method as claimed in claim 1 in which the inert atmosphere is argon gas.
Claim 12
Dependent Claim
12 words
A reactive metal produced by a method as claimed in claim 5.
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) | 1982-10-01 | 1983-04-02 | 1983-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-01 | 1987-04-02 | 1987-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-01 | 1991-04-02 | 1991-10-02 | $7700.00 | Window Closed / Lapsed |