US3911997A - Magnetic apparatus for metal casting - Google Patents

Magnetic apparatus for metal casting Download PDF

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Publication number
US3911997A
US3911997A US425951A US42595173A US3911997A US 3911997 A US3911997 A US 3911997A US 425951 A US425951 A US 425951A US 42595173 A US42595173 A US 42595173A US 3911997 A US3911997 A US 3911997A
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US
United States
Prior art keywords
magneto
holding means
metal
solenoid
static
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US425951A
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English (en)
Inventor
Kiyoshi Sugazawa
Kiyoto Ushijima
Kantaro Sasaki
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Nippon Steel Corp
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Sumitomo Metal Industries Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/122—Accessories for subsequent treating or working cast stock in situ using magnetic fields
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S505/00—Superconductor technology: apparatus, material, process
    • Y10S505/825—Apparatus per se, device per se, or process of making or operating same
    • Y10S505/912—Metal founding
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S505/00—Superconductor technology: apparatus, material, process
    • Y10S505/825—Apparatus per se, device per se, or process of making or operating same
    • Y10S505/912—Metal founding
    • Y10S505/913—Casting process
    • Y10S505/914—Casting process using magnetic or electric field

Definitions

  • MAGNETIC APPARATUS FOR METAL CASTING Inventors: Kiyoshi Sugazawa; Kiyoto Ushijima,
  • the mageto-static field generator is accommodated within a cryostat, which is always held cool at a predetermined temperature by a special auxiliary cooling means.
  • MAGNETIC APPARATUS FOR METAL CASTING This invention relates to metal casting and, more particularly, to a process and apparatus for metal casting, which makes it possible to prevent or reduce macro or micro or micrometallographic heterogenity resulting chiefly at the center of ingots or continuously casted billets from the gradual cooling, cooling or rapid cooling of liquid metal poured into the mould or liquid metal core remaining within the solidified metal shell. This is accomplished by applying magneto-static field at least in excess of 10,000 gauss to the liquid metal or liquid metal core during the solidification thereof, thereby to obtain an ingot or billet having a homogenious metallographic structure.
  • the prior-art methods for electromagnetically causing the flow of liquid metal include: a rotating electromagnetic field method as disclosed, for instance, in Dukefriet Unkhans patent (Japanese Patent Publication No. 9962/1956); one using an electromagnetic field set up by three-phase alternating current as disclosed in Japanese Patent Publication No. 32486/1972; and one using a travelling electromagnetic field set up by alternating current as disclosed in US. Pat. No. 3,656,537. All these prior-art methods have resorted to a copper wire coil which is disposed to surround or disposed in the close proximity of the mold or metal shell and through which single or three phase alternating current is caused, whereby the liquid metal is electromagnetically agitated due to alternating magnetic field set up in it and eddy current induced in it.
  • a very intensive magnetic-static field at least in excess of 10,000 gauss is set up in the liquid metal by a single magnet.
  • the size and cost of the magnetic field generator may be extremely reduced. While sufficient electromagnetic agitating effect can be obtained with a single magnetic field generator or magnet according to the invention, further strong electromagnetic agitating effect may be given to the liquid metal by a combination of a plurality of magneto-static field generators arranged such as to provide the most effective magnetic flux distribution. Thus, it is possible to obtain a strong agitating force that could not be obtained by the priorart alternating current method with an extremely small and inexpensive apparatus as compared to the prior-art one.
  • the magneto-static field is set up by direct current through a superconducting solenoid magnet.
  • the superconducting solenoid is made of a superconducting metal having a character of offering zero electric resistance at the temperature of liquid helium (268.9C) such as a niobium-tin intermetallic compound and a niobium-titanium alloy, and it is held at the termperature of liquid helium when it carries direct current.
  • liquid helium 268.9C
  • the solenoid offers zero electric resistance at the working temperature, it may use a very fine wire or filament and may be formed in a very small size with a large number of turns.
  • the solenoid as a whole may be readily held at the liquid helium temperature, it is readily possible to produce a high magneto-static field of 70,000 to 100,000 gauss at the center of the solenoid.
  • FIG. 1 is a schematic representation of a set-up using superconducting solenoid magnets according to the invention applied to a still casting process;
  • FIGS. 2 to 4 are schematic representations of set-ups according to the invention applied to a continuous cast-- ing process
  • FIG. 5 shows a cryostat
  • FIG. 6 shows a schematic liquid helium circulating system used for a continuous casting process according to the invention.
  • FIGS. 7A and 7B are graphs showing sulphur and carbon assay content distributions in a billet obtained in accordance with the invention and a billet obtained without using any agitating electromagnetic field.
  • FIG. 1 shows a set-up according to the invention with a superconducting solenoid magnet disposed in the vicinity of one side of a still mold for setting up an intensive magneto-static field in the liquid metal within the mold.
  • reference numeral 1 designates a mould made from a non-magnetic material
  • numeral 2 a solid metal shell surrounding liquid metal 3.
  • Numeral 5 designates the superconducting solenoid magnet, which is disposed in the vicinity of one side of the mold that the magnetic flux generated by it may act upon the liquid metal.
  • the solenoid magnet 5 is supported within a cryostat 7, and in this embodiment it is held in position by a non-magnetic support 8.
  • the cryostat 7 is a high performance insulated vessel having an evacuated double-wall insulating structure made of a non-magnetic metal. It is filled with liquid helium, whose surface level 9 is held at a substantially constant level. The liquid helium is replenished from a feed pipe 10, and evaporated helium is recirculated through a discharge pipe 1 l to a helium liquifier.
  • the cryostat has an upper flange 21 provided with a power lead terminal 12 for supplying power to the solenoid magnet 5.
  • a heat insulator 15 is insterposed between the cryostat and the mold for protecting the wall structure of the cryostat.
  • the magnetic flux 6 set up by the solenoid magnet and acting upon the liquid metal may be moved relative to the liquid metal by vertically oscillating the cryostat by means of a vertically movable stand 13 or by horizontally moving the mould by vertically movable stand 13 or by horizontally moving the mould by means of wheels 16 and rails 17, so that the intensive magneto-static field may efficiently act upon the liquid metal so as to evoke the fiow thereof in the desired direction.
  • FIGS. 2 to 4 show other forms of the invention applied to the continuous casting process.
  • the cryostat is not shown but is implied.
  • numeral 1 designates a bottomless water cooled mold
  • numeral 2 a solidified metal shell enclosing non-solidified or liquid metal 3.
  • the billet containing the liquid metal is withdrawn at a substantially constant speed in the direction of arrow 4.
  • two solenoid magnets are provided with respectively opposite poles (N and S poles) directed toward the shell.
  • both the solenoid magnets and 5-1 are disposed on the same side of the shell and at different vertical positions.
  • the two solenoid magnets 5 and 5-1 are disposed on opposite sides of the shell and at different vertical positions. With the disposition of the solenoid magnets with respect to the lateral direction of the billet as in the example of FIG. 2, an extremely improved agitating effect may be obtained.
  • the billet is withdrawn substantially at a constant speed, and this means that the solenoid magnet is always moved relative to the liquid metal.
  • the cryostat oscillating means as has been mentioned in connection with FIG. 1 is not needed.
  • the agitating effect of the magneto-static field upon the liquid metal is attributable not only to the eddy current induced but also to the gradient of the intensity or flux density of the field in the liquid metal.
  • the liquid metal about to solidify is subjected to the combined effect of eddy current and gradient of the field.
  • the billet is continuously withdrawn, so that the liquid metal enclosed within the solid shell proceeds usually at a speed of, for instance, 0.5 to 3 meters per minute. Due to its interaction with the magneto-static field, the liquid metal experiences forces tending to stop its movement. However, since there is a gradient of the field in the liquid metal, there also results a gradient of the intensity of the force acting upon the liquid metal, so that the liquid metal is agitated. Although a gradient of the field is formed solely with a single magnet, the magnetic flux pattern may be changed to suit the type of casting and various specifications of the ingot or billet to be produced by appropriately changing the number and disposition of the solenoid magnets as typically shown in the examples of FIGS. 2 to 4.
  • the solenoid magnet for generating the magnetic field is designed by taking various conditions such as the intensity of the exerted force and the position of installation into consideration.
  • FIGS. 5 and 6 show examples of apparatus required for the execution of the invention.
  • FIG. 5 shows an example of the cryostat.
  • the illustrated cryostat, generally designated at 7, essentially consists of an upper part having a lower flange 22 and a lower part accommodating a solenoid magnet 5. Its interior is in comm unication with a vacuum pump not shown, through a pipe 23 and is held under a pressure of [0'5 mm Hg.
  • Numeral 24 designates a magnet case, whose top communicates with a pipe 25. Liquid helium is supplied from a liquid helium feed pipe 10 to fill the case 24 and pipe 25 to a constant level 9.
  • Evaporated helium is recirculated through a discharge pipe 11 to a helium liquifier as shown in FIG. 6.
  • This example uses liquid nitrogen having a vaporization temperature of -l 958C as auxiliary cooling means to take up external heat with respect to the cryostat for ensuring steady cooling effect of the liquid helium.
  • a liquid nitrogen chamber 26 having a plurality of downwardly extending fine tubes 27 is provided within the upper part of the cryostat. Liquid nitrogen is supplied through a supply tube 29, and evaporated nitrogen is exhausted through an exhaust tube to the out side.
  • the cryostat used for the invention is entirely made of such non-magnetic material as stainless steel 304.
  • the actual apparatus will include a liquid level gauge, a thermometer, a vacuum gauge, power lead terminals for the magnet 5, a magnet position adjuster, a safety device and heat insulation means.
  • FIG. 6 shows an example of the liquid helium supply system employed for a continuous casting process of curved strand type.
  • liquid metal is poured from a pouring system 31 into a bottomless water cooled mold 1.
  • Solenoid magnets 5 and 5-2 are arranged in a way as in the example of FIG. 3 on the path of the strand 2 emerging from the mold 1 directly below or in the secondary cooling zone.
  • Liquid helium and liquid nitrogen are supplied to the cryostat and evaporated gas is recovered in the manner as described above. Only the recirculation of helium is shown.
  • Helium gas stored under a pressure of about atm. in helium gas bombs 33 and under a pressure of about I atm.
  • a helium gas tank 34 in a helium gas tank 34 is supplied to a helium gas compressor 35, and pressurised helium gas from the compressor 35 is supplied to a high pressure helium gas tank 36, and thence to a helium liquifier 37.
  • the high pressure helium gas is subjected to heat exchange with liquid nitrogen and then passed through a gas expander, whereby it is rendered into liquid helium, which is supplied through a liquid helium tank 38 to the cryostat 7.
  • evaporated helium from the cryostat goes to the helium gas tank 34 either through the liquifier 37 or directly for recovery of liquid helium for recirculation.
  • liquid helium is expensive, substantially no helium is lost in the course of the recirculation involving evaporation and liquefaction since the processed helium is recirculated through a closed loop. Also, in the iron making plants provided with apparatus for producing oxygen, liquid nitrogen is inexpensively and readily avialable as a by-product. Thus, no debit factor is found from the standpoint of the running cost.
  • the chemical composition of the steel was 0.15 percent carbon, 0.30 percent silicon, 0.71 percent manganese, 0.010 percent phosphor, 0.012 percent sulphur and 0.030 percent soluble aluminum, the rest being iron.
  • the resultant billet had a thickness of 130 millimeters and a width of 260 millimeters.
  • the magneto-static field generator was disposed directly below the mold, with its magnets positioned in the proximity of one broader side of the billet, that is as in the arrangement in FIG. 2.
  • the first half of the steel namely 1,000 kilograms of steel, was casted without applying any magnetic field, and the field was applied for the remaining half.
  • the billet obtained in this way was sampled at its positions corresponding to the feed of 400 kilograms and 1,600 kilograms respectively from the start of the casting. From each of these samples assay test pieces were cut out at intervals of 2 to millimeters in the direction ofthe thickness of the billet for examining the segregation of component elements. The results of the tests are shown in FIGS. 7A and 78. It will be seen that the billet obtained by applying the magneto-static field resulted in very little segregation of carbon sulphur at the center compared to the billet obtained without any field applied. Also, it was confirmed that the magnetostatic field applied is particularly effective in the refinement of the dendrite grain structure and capable of reducing the segregation coefficient down to well below 2.0.
  • the specifications of the magnets used in this experiment were as follows:
  • Solenoid wire Copper wire 0.4 mm in diameter and containing 40 sealed fine filaments of Nb-Ti alloy resin coating being provided after winding the wire.
  • An apparatus for casting metals comprising means for holding non-solidified metal, means for generating a heterogenious magneto-static field in said nonsolidified metal, said generating means being disposed in the vicinity of one side of said holding means, and means for causing relative movement of said holding means and generating means to each other.
  • said magneto-static field generating means includes at least one super-conducting solenoid magnet.
  • said moving means includes wheels carried by a wagon supporting said mold and rails to guide and support said wheels.
  • magneto-static field generating means can generate a magneto'static field of intensities above 10,000 gauss in said non-solidified metal.
  • said magneto-static means includes a plurality of superconducting solenoid magnets disposed on opposite sides of said holding means with opposite poles directed toward the opposite sides of said holding means.
  • said magneto-static means includes a plurality of superconducting solenoid magnets disposed on opposite sides of said holding means with like poles directed toward the opposite sides of said holding means.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Mixers With Rotating Receptacles And Mixers With Vibration Mechanisms (AREA)
US425951A 1972-12-20 1973-12-19 Magnetic apparatus for metal casting Expired - Lifetime US3911997A (en)

Applications Claiming Priority (1)

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JP47128555A JPS5236492B2 (enrdf_load_stackoverflow) 1972-12-20 1972-12-20

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US (1) US3911997A (enrdf_load_stackoverflow)
JP (1) JPS5236492B2 (enrdf_load_stackoverflow)
DE (1) DE2363609B2 (enrdf_load_stackoverflow)
FR (1) FR2211308B1 (enrdf_load_stackoverflow)
GB (1) GB1457900A (enrdf_load_stackoverflow)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4183395A (en) * 1977-02-03 1980-01-15 Asea Aktiebolag Multi-phase stirrer
US4515203A (en) * 1980-04-02 1985-05-07 Kabushiki Kaisha Kobe Seiko Sho Continuous steel casting process
US4562879A (en) * 1982-06-18 1986-01-07 Institut De Recherches De La Siderurgie Francaise Electromagnetically stirring the melt in a continuous-casting mold
US5246060A (en) * 1991-11-13 1993-09-21 Aluminum Company Of America Process for ingot casting employing a magnetic field for reducing macrosegregation and associated apparatus and ingot
US5632324A (en) * 1994-07-14 1997-05-27 Kawasaki Steel Corporation Method of continuously casting steels
US6579490B1 (en) * 1999-10-05 2003-06-17 Nagoya University Apparatus for generating compression waves in conductive liquid
US20080251231A1 (en) * 2005-12-24 2008-10-16 Concast Ag Method and apparatus for the continuous casting of preliminary steel sections
US9180511B2 (en) 2012-04-12 2015-11-10 Rel, Inc. Thermal isolation for casting articles
CN113337704A (zh) * 2021-05-31 2021-09-03 四川大学 一种通过静磁场设施实现交变或脉冲磁场作用的方法
US20230234126A1 (en) * 2020-06-18 2023-07-27 Voestalpine Additive Manufacturing Center Gmbh Actuator for a casting mold for producing metal components

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50148233A (enrdf_load_stackoverflow) * 1974-05-21 1975-11-27
FR2324397B1 (fr) * 1975-09-19 1979-06-15 Siderurgie Fse Inst Rech Procede et dispositif pour le brassage electromagnetique des produits de coulee continue
DE2812279C3 (de) * 1978-03-21 1982-10-07 Bhattacharya, Sylvia, 2832 Twistringen Verfahren und Vorrichtung zum Steuern des Erstarrens eines gegossenen metallischen Werkstoffstückes
AT362088B (de) * 1979-08-01 1981-04-27 Voest Alpine Ag Ruehreinrichtung an einer stranggiessanlage
FR2660107B1 (fr) * 1990-03-22 1994-07-29 Centre Nat Rech Scient Procede de preparation d'un corps magnetique oriente et texture.
WO1997018916A1 (fr) * 1995-11-24 1997-05-29 Dmitry Alexandrovich Djudkin Procede de coulee de metal

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1419280A (en) * 1920-02-07 1922-06-13 John D Mcneill Apparatus for rendering metal homogeneous
US3464812A (en) * 1966-03-29 1969-09-02 Massachusetts Inst Technology Process for making solids and products thereof
US3809145A (en) * 1971-06-15 1974-05-07 Preussag Ag Process for the production of permanent magnets

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1419280A (en) * 1920-02-07 1922-06-13 John D Mcneill Apparatus for rendering metal homogeneous
US3464812A (en) * 1966-03-29 1969-09-02 Massachusetts Inst Technology Process for making solids and products thereof
US3809145A (en) * 1971-06-15 1974-05-07 Preussag Ag Process for the production of permanent magnets

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4183395A (en) * 1977-02-03 1980-01-15 Asea Aktiebolag Multi-phase stirrer
US4515203A (en) * 1980-04-02 1985-05-07 Kabushiki Kaisha Kobe Seiko Sho Continuous steel casting process
US4562879A (en) * 1982-06-18 1986-01-07 Institut De Recherches De La Siderurgie Francaise Electromagnetically stirring the melt in a continuous-casting mold
US5246060A (en) * 1991-11-13 1993-09-21 Aluminum Company Of America Process for ingot casting employing a magnetic field for reducing macrosegregation and associated apparatus and ingot
US5375647A (en) * 1991-11-13 1994-12-27 Aluminum Company Of America Process for ingot casting employing a magnetic field for reducing macrosegregation and associated apparatus and ingot
US5632324A (en) * 1994-07-14 1997-05-27 Kawasaki Steel Corporation Method of continuously casting steels
US6579490B1 (en) * 1999-10-05 2003-06-17 Nagoya University Apparatus for generating compression waves in conductive liquid
US20080251231A1 (en) * 2005-12-24 2008-10-16 Concast Ag Method and apparatus for the continuous casting of preliminary steel sections
US8109320B2 (en) * 2005-12-24 2012-02-07 Concast Ag Method and apparatus for the continuous casting of preliminary steel sections
US9180511B2 (en) 2012-04-12 2015-11-10 Rel, Inc. Thermal isolation for casting articles
US10179364B2 (en) 2012-04-12 2019-01-15 Rel, Inc. Thermal isolation for casting articles
US10434568B2 (en) 2012-04-12 2019-10-08 Loukus Technologies, Inc. Thermal isolation spray for casting articles
US20230234126A1 (en) * 2020-06-18 2023-07-27 Voestalpine Additive Manufacturing Center Gmbh Actuator for a casting mold for producing metal components
CN113337704A (zh) * 2021-05-31 2021-09-03 四川大学 一种通过静磁场设施实现交变或脉冲磁场作用的方法
CN113337704B (zh) * 2021-05-31 2023-06-16 成都昆吾科技有限公司 一种通过静磁场设施实现交变或脉冲磁场作用的方法

Also Published As

Publication number Publication date
DE2363609A1 (de) 1974-07-18
GB1457900A (en) 1976-12-08
DE2363609B2 (de) 1976-01-15
JPS5236492B2 (enrdf_load_stackoverflow) 1977-09-16
FR2211308A1 (enrdf_load_stackoverflow) 1974-07-19
FR2211308B1 (enrdf_load_stackoverflow) 1978-03-24
JPS4984923A (enrdf_load_stackoverflow) 1974-08-15

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