US4583580A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous casting method and ingot produced thereby
Assignee: ELECTRO-METALS A CA CORP (A DIVISION OF DEMETRON INC)
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Filing: 1984-09-28
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Granted: 1986-04-22
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Expires: 2004-09-28
Abstract
Abstract A method is described for continuously casting an ingot of a metal alloy of a type having a substantial liquidus-solidus temperature range to produce internal microstructure of a desired fineness. Molten alloy is flowed along an electron beam heated skulled hearth while controlling the electron beam to maintain a solids content in the alloy on the hearth of between about 15% and about 40%. The alloy is poured from the hearth into the top of a continuous casting mold at a rate which produces a thixotropic region at the upper end of the fully solidified alloy in the mold. The ingot produced is characterized by a macrostructure in excess of one millimeter average grain dimensions with a non-uniform shape, orientation, and distribution, and is characterized by a microstructure of the order of fifty micron cell spacing of dendritic crystallites comprising the microstructure.
Inventors
- 👤 Charles D. Hunt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:07
CPC Classifications
B; B22; B22D; B22D11/00; B22D11/10; B22D11/11; Y; Y10; Y10S; Y10S164/00; Y10S164/90
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
177 words
A method of continuously casting an ingot of a metal alloy of a type having a substantial liquidus-solidus temperature range to produce internal microstructure of a desired fineness, said method comprising: flowing the molten alloy along an electron beam heated skulled hearth while controlling the electron beams to maintain a solids content in the alloy on the hearth of between about 15% and about 40%, pouring the molten alloy from the hearth into the top of a continuous casting mold at a rate sufficient to cause the maintenance of a fluid pool at the top of the ingot and a substantial thixotropic region below the pool at the upper end of the fully solidified portion of the alloy in the mold and below the region at which the molten alloy from the hearth enters the mold, said thixotropic region having a solids content of at least about 50%, and withdrawing the solidified alloy from the mold at a rate of between about 0.15 kilograms per hour per square centimeter and 0.90 kilograms per hour per square centimeter.
Claim 2
Independent Claim
177 words
A method of continuously casting an ingot of a metal alloy of a type having a substantial liquidus-solidus temperature range to produce internal microstructure of a desired fineness, said method comprising: flowing the molten alloy along an electron beam heated skulled hearth while controlling the electron beams to maintain a solids content in the alloy on the hearth of between about 15% and about 40%, pouring the molten alloy from the hearth into the top of a continuous casting mold at a rate sufficient to cause the maintenance of a fluid pool at the top of the ingot and a substantial thixotropic region below the pool at the upper end of the fully solidified portion of the alloy in the mold and below the region at which the molten alloy from the hearth enters the mold, said thixotropic region having a solids content of at least about 50%, and withdrawing the solidified alloy from the mold at a rate of between about 0.15 kilograms per hour per square centimeter and 0.90 kilograms per hour per square centimeter.
Claim 3
Dependent Claim
36 words
A method according to claim 1 wherein the surface of the alloy in the top of the mold is heated by electron beam heating at the periphery adjacent the mold to provide a relatively smooth sidewall.
Claim 4
Dependent Claim
12 words
A method according to claim 1 wherein the solidified is withdrawn continuously.
Claim 5
Dependent Claim
18 words
A method according to claim 1 wherein the solidified alloy is withdrawn in a series of preselected increments.
Claim 6
Dependent Claim
26 words
A method according to claim 1 wherein the ingot is formed of an alloy having a liquidus-solidus temperature range between about 50° C. and 150° C.
Claim 7
Dependent Claim
32 words
A method according to claim 1 wherein the alloy is a nickel or cobalt base alloy containing at least about 50% nickel or cobalt, respectively, and between about 10% and 25% chromium.
Claim 8
Dependent Claim
40 words
A method according to claim 1 wherein the depth of non-thixotropic molten alloy at the top of the ingot in the mold is between about one fourth the diameter of the ingot and three times the diameter of the ingot.
Claim 9
Dependent Claim
42 words
A method according to claim 1 wherein the hearth conditions and the pourihg rate is controlled so that the local cooling rate at the surface of the molten alloy in the hearth and the mold corresponds to about 50° C. per second.
Claim 10
Dependent Claim
26 words
A method according to claim 1 wherein the average depth of the molten alloy in the hearth is maintained between about 0.75 centimeters and 1.5 centimeters.
Claim 11
Independent Claim
223 words
A method of continuously casting an ingot of a metal alloy of a type having a substantial liquidus-solidus temperature range to produce internal microstructure of a desired fineness, said method comprising: flowing the molten alloy along an electron beam heated skulled hearth while controlling the electron beams to maintain a solids content in the alloy on the hearth of a predetermined percentage, pouring the molten metal from the hearth into the top of a continuous casting mold while heating the surface of the alloy in the top of the mold by electron beam at the periphery of the ingot adjacent the mold to provide a relatively smooth side wall, while avoiding substantial heating of the ingot in any other region, and controlling the predetermined solids content of the alloy on the hearth and the pouring rate of the molten alloy from the hearth into the top of the continuous casting mold to cause the maintenance of a fluid pool at the top of the ingot and a substantial thixotropic region below the pool at the upper end of the fully solidified portion of the alloy in the mold and below the region at which the molten alloy from the hearth enters the mold, said thixotropic region having a solids content of at least about 50%, and withdrawing the solidified ingot from the mold.
Claim 12
Independent Claim
223 words
A method of continuously casting an ingot of a metal alloy of a type having a substantial liquidus-solidus temperature range to produce internal microstructure of a desired fineness, said method comprising: flowing the molten alloy along an electron beam heated skulled hearth while controlling the electron beams to maintain a solids content in the alloy on the hearth of a predetermined percentage, pouring the molten metal from the hearth into the top of a continuous casting mold while heating the surface of the alloy in the top of the mold by electron beam at the periphery of the ingot adjacent the mold to provide a relatively smooth side wall, while avoiding substantial heating of the ingot in any other region, and controlling the predetermined solids content of the alloy on the hearth and the pouring rate of the molten alloy from the hearth into the top of the continuous casting mold to cause the maintenance of a fluid pool at the top of the ingot and a substantial thixotropic region below the pool at the upper end of the fully solidified portion of the alloy in the mold and below the region at which the molten alloy from the hearth enters the mold, said thixotropic region having a solids content of at least about 50%, and withdrawing the solidified ingot from the mold.
References Cited (Backward Citations)
US3343828A
Cited
US3948650A
Cited
US3951651A
Cited
US3954455A
Cited
US3902544A
Cited
US4089680A
Cited
US4261412A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-21 | 1989-10-21 | 1990-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-21 | 1993-10-21 | 1994-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-21 | 1997-10-21 | 1998-04-22 | $7700.00 | Window Closed / Lapsed |