KR20250026445A - Electromagnetic stirring device and method for melting and distribution furnaces for non-ferrous high alloyed alloys - Google Patents

Abstract

An electromagnetic stirring device for a melting and distribution furnace of a non-ferrous high-alloy alloy comprises: a crucible having a space for accommodating molten metal; three-phase magnetic cores formed radially in a symmetrical shape on the lower side of the crucible; three poles respectively arranged on the upper side of the three magnetic cores; three coils respectively surrounding the three poles; and a power source for supplying variable current to the coils, wherein the molten metal is stirred by an electromagnetic field generated according to the supply of the current.

Description

{Electromagnetic stirring device and method for melting and distribution furnaces for non-ferrous high alloyed alloys}

The present invention relates to metallurgy and casting technology for processes related to melting, holding and pouring of a composite alloy which is liable to be separated mainly by the chemical composition of the alloy, and is most applicable to continuous casting processes such as billet, slab and bloom, and to casting technology for improving quality including electromagnetically controlled stirring, homogenization in a liquid state by chemical composition and temperature, electromagnetic refining and microstructural control.

'This study was conducted with the support of the Nano and Materials Technology Development Project (2021M3H4A3A02093507) funded by the Ministry of Science and ICT.'

As is well known, complex high alloyed types of aluminum alloys, such as the 7000 series, have a tendency to separate out in their chemical composition or have a high dross capacity, for example, towards highly reactive alloying elements. This is particularly necessary for stirring, homogenizing, maintaining or refining the artificial molten metal in the bath of the foundry during casting.

In these cases, as well as for alloys such as aluminum-magnesium, aluminum-zinc, aluminum-copper, etc., classical crucible electric resistance melting and pouring furnaces realize internal stirring only by natural heat convection means by heating the molten metal by heating elements located outside and around the SiC cylindrical crucible. However, in the case of high-alloy type aluminum alloys, if alloying elements having a concentration higher than the natural solubility in aluminum are used, a segregation phenomenon due to chemical composition may occur.

For example, in the case of Al-5%Mg, the dissolution ratio of aluminum is 1.4%, so magnesium floats to the surface at a critical concentration of 3 to 10% in the upper tank. In addition, high concentrations of magnesium easily destroy the Al2O3 oxide film that protects the aluminum alloy from oxidation, but magnesium begins to oxidize more quickly when interacting with oxygen. In addition, the concentration of Mg in the bottom part of the melting furnace crucible decreases to 1.5 to 3% or less. As a result, these alloys require periodic artificial mixing, and inertial gases such as Ag or nitrogen must be used for protection from the atmosphere.

In particular, for 7000 series aluminum alloys such as 7075 or 7068, when the zinc content is 6-8% or more, magnesium 2.5-3%, and copper 1.5-2%, the chemical separation is more evident when the zinc sinks and magnesium floats during long-term melting. To solve this problem, it is necessary to artificially homogenize the liquid metal. In this case, the most suitable tool for implementing forced mixing of the melt in the foundry type is an electromagnetic stirrer providing an alternating pulsating magnetic field.

The classic application of these electromagnetic devices is in metallurgical melting furnaces, where they are used as reverberation type. Electromagnetic stirrers of various designs, known as single-phase, three-phase and multi-phase, are usually installed on the side wall of the melting unit or in the floor position, including channel or wall types. However, in the case of crucible-type melting furnaces, EMS applications are very rare due to the locational constraints that require the electromagnetic system to be installed as close as possible to the molten metal.

The crucible electrical resistance melting furnace is a cylindrical metal case, which is generally a ceramic or metal crucible, which serves as the main container for the molten metal, and has a heater installed inside, and an inner wall refractory insulation layer installed, so that the heater is installed at the closest position to the molten metal. The thickness of a typical crucible is 30 to 60 mm, and it is very fragile. Since the heat energy is transferred from the heater to the molten metal through the crucible material, which must have high temperature and thermal conductivity at temperatures of up to 1000℃, such as aluminum alloy, the wall thickness of the crucible must be thin to provide high thermal conductivity.

The upper part of the crucible is open for ingot internal charging, melt exchange and refining, and there should be no other processing equipment. The bottom of the crucible is usually placed with a "bottom stone", which is placed on the refractory material on the steel bottom cover. Generally, the "bottom stone" and the refractory should be strong and have very low thermal conductivity, because the bottom part of the furnace is where all the heavy alloys with the crucible loading are located. In addition, the distance from the molten metal of the crucible to the bottom edge of the furnace is generally 200 to 500 mm from the safety point of view. And from the point of view of installation, only the bottom part of this type of furnace can be used to place the electromagnetic stirrer. In addition, the artificial electromagnetic molten metal stirring exactly at the bottom part can be the best solution for the application of forced melt stirring.

From a fluid dynamic point of view of mixing efficiency, the most highly regarded melt mixing mode, especially in the geometry of a crucible electrical resistance melting furnace, can have at least two modes.

1) The toroidal melt is mixed in the vertical axial plane, and the resulting axial submerged jet melt is lifted upward from below and returns from the surface to the bottom along the side of the crucible in a terminal circulation mode.

2) Rotating circulating melt is generated in the side wall crucible area by the pressure increase due to the centrifugal effect and the pressure decrease in the center, melting in the horizontal plane in a clockwise or counterclockwise direction, and providing secondary melt mixing from the outer vortex edge to the inner edge by the decreasing vortex power.

The first type, toroidal vertical stirring, can be activated by an artificial vertical electromagnetic force generated from the lower crucible of the shaft. The second type, rotary stirring, can be generated by a rotating magnetic field applied to the bottom edge of the crucible.

However, from a fluid dynamics perspective, when creating unidirectional vertical or rotational mixing, a low-pressure region is created in the center of the mixing circuit during decomposition in the crucible tank, which has the disadvantage that non-metallic inclusions with a lower density than the base are melted.

Therefore, after creating a combination of time-varying structures of vertical toroids, switching to horizontal rotation or vice versa can solve the problem of forming macro-eddy motions with negative dead zones and low-pressure zones, and provide stable circulation of the melt.

In addition, it is desirable that the mixing device be compact and be combined with the structure of the melting furnace. This is especially true when the melting furnace is of a tilting type and, depending on its function, the melt in the crucible must be continuously mixed at an inclined position.

To date, various electromagnetic methods and devices for melt mixing in melting, metallurgical and pouring furnaces are known. The main part of the electromagnetic device is used in a melting furnace without a crucible, and can be located on the side or bottom of the melting furnace with a decreasing lining thickness in the docking area of the electromagnet, as in British patent GB 2389645A.

A classic and practical system for equipping many technology foundry facilities is the electromagnetic stirring system of the melt by means of an induction electromagnetic stirrer in a moving magnetic field. The inductor can be used for forced vertical stirring of the melt in a smelting vessel or in a low-flow melt casting system.

However, there are few examples of using an electromagnetic stirrer in a crucible melting and maintenance furnace because the distance from the melting furnace body to the cavity containing the melt is long, and in this case, the magnetic field penetration area is very low, making it virtually impossible to use a rotating or traveling magnetic field.

Therefore, the main point of improvement is to increase the effective range of the electromagnetic field by using low-frequency magnetic fields of units or tens of hertz or by using specially designed electromagnets.

The electromagnetic stirring method of liquid metal is also widely known, which is implemented in such a way that the force applied to the metal and the pulsed magnetic field are periodically changed, and the melt changes its direction of movement in the opposite magnetic field. Its efficiency is due to the fact that the turbulent mixing region of the binary alloy system under the pulsating electromagnetic field and the pulsating electromagnetic force is limited to the region where the polar electromagnetic system is attached. The effect of the mechanical vibration action on the binary alloy system is limited by the high energy of the dissipative wave in the liquid melt. Therefore, the dispersion effect is reduced due to the periodic changing mode of the electromagnetic system operating in the moving melting mode under the pulsation by the magnetic field, thereby forming a circulating path of laminar and eddy currents in the melting tank.

In the well-known electromagnetic stirrer of a pulsating magnetic field for liquid metals, a single-phase electromagnet with a T-shaped monopole magnetic wire is used as the main device.

Test results show that the effectiveness of this mixing can be verified when the melt jet velocity in the submerged jet core reaches up to 1 m/s when the distance from the magnetic field to the melt is 100 to 150 mm. In this case, the use of a standard network frequency of 50 to 60 Hz can be considered.

However, if a single-phase current with a load capacity of 5 to 50 kW or more is used in the power grid, it will have a significant impact on the phase shift in the three-phase electrical system of the workplace, and in particular, the high reactive power without compensation by capacitors will have a significant negative impact on the three-phase power supply system of the factory.

Also, when using electromagnet poles and liquid metals with ceramics, it is possible to use them in the medium frequency range, such as 50–60 Hz. However, when the metal plate and the magnetic field interact, the intensity of the magnetic field drops significantly at the electric network frequency of 50–60 Hz due to the activation of induced electric eddy currents. In addition, when overheated to a high temperature of 600°C or higher, the metal structure may undergo thermal deformation, so several electrical insulation cuties must be created, which seriously reduces the mechanical durability of the furnace structure.

There is also a well-known method of processing a melt in an induction crucible furnace and preparing a composite material. Here, a low-frequency electromagnetic system with a pulsating magnetic field is installed at the bottom of the crucible together with an induction heating system. From a conceptual point of view, this can be used as a prototype of the present invention.

Today, for induction furnaces, especially in the special case of frequency modulation, there is a solution using multi-frequency feeding of the inductor for alternating crucible heating mode and using the operating frequency in the low frequency range, which is a reasonable decision.

Additionally, the simultaneous use of the main inductor and an additional electromagnetic floor mixing system can result in passive mutual influences and the generation of harmonics, high frequencies that are harmful to the power grid.

In most cases, the application of these technological solutions requires significant changes in the design of the melting device, channel connections, special electromagnetic transparent windows, etc. in the installation area of the electromagnetic stirrer to ensure the efficiency of electromagnetic mixing. However, this leads to a limited penetration range of electromagnetic waves and high energy losses during the formation of electronic eddy currents in magnetic and thick-walled non-magnetic materials.

The use of low-frequency magnetic fields is a good solution, but due to their low energy and hydrodynamic efficiency, they can only be used in exceptional situations where mixing is virtually impossible.

From the fluid dynamics point of view of mixing, the moving magnetic field providing the directional mixing mode is the most feasible deformation mode. However, since the area of action of the moving magnetic field is usually very narrow, a maximum estimate of the poles of the inductor is required.

British Patent No. 2389645 (registered on April 11, 2007)

The technical problem to be achieved by the present invention is to provide a method and device for electromagnetically mixing, homogenizing, and maintaining a highly homogeneous state of a high-alloy aluminum melt that is easily separated chemically and thermally by applying it to a crucible-type melting distribution industrial furnace of an electric resistance heating method.

The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to one embodiment of the present invention for achieving the above technical task, an electromagnetic stirring device for a melting and distribution furnace of a non-ferrous high-alloy alloy comprises: a crucible having a space for accommodating molten metal; three-phase magnetic cores radially formed in a symmetrical shape on the lower side of the crucible; three poles respectively arranged on the upper sides of the three magnetic cores; three coils respectively surrounding the three poles; and a power source for supplying variable current to the coils, characterized in that the molten metal is stirred by an electromagnetic field generated according to the supply of the current.

The above electromagnetic stirring device further includes a main frame for tiltingly mounting the crucible; and a rail for supporting the main frame so as to be able to move in a linear direction.

The above magnetic core is composed of T-shaped magnetic cores assembled in a horizontal plane at an angle of 120 degrees to each other so that the electromagnetic field is directed to the molten metal in the crucible.

By the electromagnetic field generated above, the direction and intensity of stirring are controlled so that the molten metal is stirred horizontally and axially with respect to the crucible.

The above-mentioned generated electric field is a unidirectional electromagnetic field, and the intensity of the vertical toroidal melting stirrer is controlled by the unidirectional electromagnetic field so that the molten metal is stirred axially with respect to the crucible.

A first mode in which the direction and intensity of stirring are controlled so that the molten metal is stirred horizontally and axially with respect to the crucible by the generated electromagnetic field, and a second mode in which the intensity of vertical toroidal melting stirring is controlled so that the molten metal is stirred axially with respect to the crucible by the generated unidirectional electromagnetic field are used alternately over time.

In addition, according to another embodiment of the present invention for achieving the above technical task, includes .

According to the present invention, it is possible to ensure a homogeneous state of the melt in the preparation, injection and storage processes, solve chemical and temperature separation problems, reduce the degree of damage to low-melting components of the alloy, ensure high quality of the melt state, and create microstructure control conditions.

In addition, the technological speed of melting, preparation, refining and processing can be increased due to artificial electromagnetic melt stirring.

In addition, when using an alloying element that reduces the size of fine particles that are prone to precipitation, such as TiB, there is also an advantage in that the reforming effect can be significantly improved through artificial melt mixing, and the residual time, which was only about 30 to 40 minutes without melt mixing, can be increased to several hours.

Figure 1 is a local cross-sectional view of a melting and distribution crucible tilting type electric resistance furnace equipped with an electromagnetic melt stirring system.
Figure 2 is a drawing of an electromagnetic stirrer operated by a three-phase, three-pole electromagnet.
Figure 3 is a diagram showing a vertical image of three pulsating magnetic field circuits of three-phase currents, the direction of magnetic field termination and the direction of mutual movement having a phase shift of 120 degrees from each other.
FIG. 4 is a drawing illustrating a method for performing artificial melting electromagnetic stirring by controlling the intensity vertical toroidal melting stirring that forms an axis with the crucible plane by generating a unidirectional electromagnetic field.
Figure 5 is a schematic diagram of a vertical toroidal melting stirrer in the crucible plane and axial direction by a generated unidirectional electromagnetic field.
Figure 6 is a diagram showing the interaction of similar magnetic fields generated near the poles of a triple electromagnet.
Figure 7 is a drawing illustrating the rotational mixing of a melt in a crucible of a melting furnace under inclined operating conditions when generating a rotating magnetic field.
Figure 8 is a drawing illustrating vertical toroidal mixing of a melt in a crucible of a melting furnace under inclined operating conditions when generating a unidirectional magnetic field.

The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and these embodiments are provided only to make the disclosure of the present invention complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with a meaning that can be commonly understood by a person of ordinary skill in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries shall not be ideally or excessively interpreted unless explicitly specifically defined.

The terminology used herein is for the purpose of describing embodiments only and is not intended to limit the invention. In this specification, the singular also includes the plural unless specifically stated otherwise. The terms "comprises" and/or "comprising" as used herein do not exclude the presence or addition of one or more other components in addition to the components mentioned.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings.

The present invention proposes a reasonable standard type of an electric resistance melting-holding and distribution furnace of a crucible tilting type having an electromagnetic stirrer. The electromagnetic stirrer has three T-shaped magnetic cores having a horizontal main core and a pole having at least one coil. The main core and the poles direct the molten metal in the crucible vertically. Here, the three T-shaped cores are assembled at 120 degrees to the horizontal plane, respectively.

The unique fluid dynamically highly efficient melt stirring mode can be used to control the direction and speed of the melt stirred horizontally and axially with respect to the crucible face by generation of a rotating electromagnetic field. In addition, it can be controlled by the intensity of the vertical toroidal melt stirred axially with respect to the crucible face by generation of a unidirectional residual magnetic field, and the rotation time can be changed in the horizontal and vertical toroidal melt stirring.

Fig. 1 is a cross-sectional view of a localized melting and distribution crucible tilting type electric resistance furnace equipped with an electromagnetic melting stirrer. For reference, in all cases of Fig. 1 and Figs. 4, 7 and 8 below, the flow direction of the melt (7) is generally presented as a static flow diagram.

An electromagnetic stirrer (100a) for such melting may be composed of a plurality of cores (14, 15) and a plurality of coils (13, 16). The electromagnetic stirrer (100a) is installed below a crucible (6) having a melt (7) in the axial direction of the crucible surface. Here, when the melt (7) of the liquid non-ferrous high alloy is stirred electromagnetically, it is controlled in a speed rotation stirring mode in the horizontal direction and the axial direction with respect to the crucible plane by a rotating electromagnetic field (25 in FIG. 2 or 22, 23, 24 in FIG. 3). The general flow direction of the melt (7) is the same as the direction of the electromagnetic field, as indicated by the reference numeral 8 in FIG. 1.

The implementation of the method and device of the present invention is carried out in a typical crucible tilting type electric resistance heater melting-pouring furnace (5 in Fig. 1). Here, a furnace main frame (2) having a tilting axis (3) so as to be omnidirectionally movable is movably installed on a rail (1), and a furnace (5) capable of tilting in a frontal direction is mounted on the main frame (2). In the frontal location furnace (5), there is a pouring nozzle (4) capable of pouring a molten material (7) into a tundish of a mold or other continuous casting device (not shown here) for producing billets or slabs, etc.

The furnace (5) designed as a cylindrical metal case can be composed of a cylindrical metal case (e.g., SiC) installed inside an exchangeable crucible (6) having a wall thickness of 50 to 60 mm. Inside the crucible (6), a molten metal (7), for example, a high-alloy aluminum alloy of the 7000 series such as the 7075 series, is placed, along with a thermocouple (30) for melting temperature control.

Inside the metal case surrounding the inner wall of the furnace (5), an insulating material (10) made of, for example, bricks is installed along the periphery of the crucible space. At this time, when power is supplied by electricity, an electric resistance heater (9) such as Ni-Cr heats the crucible (6) in the inner space of the furnace.

At the bottom of the furnace (5), a bottom cover (12) having a curved, round shape on the inside and made of a non-magnetic material such as a stainless steel plate is installed, and the upper inside of the bottom cover (12) is covered with a strong refractory material (11). In addition, a “bottom stone” (bottom stone: 35) is placed at the upper center of the refractory material (11) to support a ceramic crucible (6) holding molten metal (7).

Below the non-magnetic bottom cover (12) of the furnace (5), a configuration for electromagnetic stirring is installed, including a magnetic core (14, 15; shown in cross section) and a coil (13, 16, 18) installed on the magnetic core.

Figure 2 is a perspective view showing an electromagnetic stirrer (100a) operated by a three-phase three-pole electromagnet, and Figure 3 is a plan view showing a vertical image of three pulsating magnetic field circuits of three-phase currents whose magnetic field termination direction and mutual movement direction have a phase shift of 120 degrees from each other.

In FIGS. 2 and 3, reference numeral 25 represents a direction of rotation due to an electromagnetic field, and reference numerals 13, 15, and 17 represent three magnetic cores. In addition, reference numerals 14, 16, and 18 represent three coils, and reference numerals 19, 20, and 21 represent three poles. In addition, reference numerals 22, 23, and 24 in FIG. 3 are separately indicated as electromagnetic field lines formed between adjacent poles.

As shown in FIGS. 2 and 3, the electromagnetic stirrer (100a) is implemented with a three-phase, three-pole electromagnet comprising three T-shaped magnetic cores (13, 15, 17) having a main core and poles horizontally, and poles having at least one coil (14, 16, 18) on each of the magnetic cores (13, 15, 17). With this configuration, the molten material or molten metal (7) can be directed in a vertical direction (blue dotted line) within the crucible (6). Here, the three T-shaped cores (13, 15, 17) can be assembled within a horizontal plane so as to have 120 degrees therebetween, as shown in FIGS. 2 and 3.

Referring to FIG. 2, the melt in the artificial melting electromagnetic stirrer (100a) is controlled in a specific direction (8 in FIG. 1), and in particular, the operation of the speed rotating electromagnetic stirring is controlled in the horizontal direction and the axial direction with respect to the crucible plane by the generated rotating electromagnetic field (25). A schematic diagram of the rotating motion magnetic field (25) is well illustrated in FIG. 2. The rotating motion of the magnetic field is concentrated on the upper plane above the three poles of the triple electromagnet, and is formed upwardly based on the vertical poles (19, 20, 21) of the electromagnet toward the melt (7) located at the lower part of the crucible (6) and the furnace (5) (see FIGS. 1 and 2).

Referring to Fig. 3, the rotating magnetic field of the three-phase, three-pole electromagnet is generated by three magnetic fluxes (22, 23, 24), which are in turn generated by three windings (14, 16, 18) supplied with power by a three-phase current source from three magnetic cores (13, 15, 17). At this time, the three windings (14, 16, 18) are interconnected in a “star” shape.

Fig. 3 shows a schematic diagram of three pulsating magnetic field circuits of three-phase current. Here, the termination and mutually moving directions of the magnetic fields (22, 23, 24) are shown to have a phase shift of 120 degrees with respect to each other. For example, if the phase order of the coils is reversed according to the operating principle of an asynchronous electric motor, the forward rotation of the rotating magnetic field can also be reversed. In order to increase the penetration depth of the magnetic field, it is preferable to use a three-phase current in the frequency range of 10 to 25 Hz when using a three-phase current frequency inverter.

As another embodiment of the present invention, FIG. 4 is a drawing explaining a method of performing stirring by an artificial melting electromagnetic field (100b) that generates a unidirectional electromagnetic field to control a strong vertical toroidal melting stirrer that forms an axis with the crucible plane.

In FIGS. 4 to 6, a form is illustrated in which vertical toroidal melt stirred in the axial direction and the crucible plane is controlled according to intensity by the generated unidirectional electromagnetic field (22, 23, 24 of FIGS. 4 and 5). In particular, in the present embodiment, the artificial melting electromagnetic stirrer (100b) controls the intensity of vertical toroidal melt stirring in the axial direction with respect to the crucible plane by the generation of a unidirectional electromagnetic field (8), as illustrated in FIG. 4.

Figure 5 is a perspective view of a vertical toroidal melting stirrer (100b) in the crucible plane and axial direction by a generated unidirectional electromagnetic field, and Figure 6 is a plan view showing the interaction of similar magnetic fields generated near the poles of a triple electromagnet.

In FIGS. 5 and 6, reference numerals 13, 15, and 17 represent three magnetic cores. In addition, reference numerals 14, 16, and 18 represent three coils, and reference numerals 19, 20, and 21 represent three poles. In addition, reference numerals 22, 23, and 24 are separately indicated as electromagnetic field lines formed between adjacent poles.

The generation of vertical unidirectional magnetic fields (22, 23, 24) along the vertical axis is achieved by three built-in T-shaped electromagnets having vertical poles (19, 20, 21) with the same phase shift relative to each other when powered by the same single-phase or two-phase current. In this case, the T-shaped electromagnets can be controlled by the superposition, algebraic addition of the three magnetic fields of the same name with the same phase shift.

From the viewpoint of constructing a reasonable hydrodynamic mode of melt mixing, the formation of a stable vortex circulation circuit of melt mixing can be prevented together with the low-pressure region inside the macro vortex and the hydrodynamic dead zone inside it. For this purpose, a mode is utilized in which the rotational mixing time of the melt in a horizontal crucible is applied in a sequential manner combined with a vertical unidirectional toroidal or vice versa.

Additionally, these modes can be implemented by electrically switching the windings of the triple electromagnets from a star-shaped three-phase connection to a single-phase or two-phase parallel connection mode, depending on the planned program of the power programmer.

The following Figures 7 and 8 illustrate a case where the crucible is tilted in a pouring state of the melt (7). Of these, Figure 7 is a drawing explaining rotational mixing of the melt in the crucible of the melting furnace under inclined working conditions when generating a rotating magnetic field. And Figure 8 is a drawing explaining vertical toroidal mixing of the melt in the crucible of the melting furnace under inclined working conditions when generating a unidirectional magnetic field.

According to the present invention, a prototype and a rational equipment concept of a tilting electric resistance melting-pouring furnace for non-ferrous alloys capable of artificial electromagnetic melting stirring in various modes are created.

In particular, it can improve the quality of the melt by solving problems such as separation of the melt by chemical composition and temperature, reduction of oxidation and dross, stabilization of homogeneous alloy in liquid state, and microstructural control of cast parts for various aluminum alloys such as high alloy and high strength 7000 series.

Although the embodiments of the present invention have been described with reference to the attached drawings, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical idea or essential features thereof. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

1: Rail 2: Main Frame
3: Tilting axis 4: Injection nozzle
5: Furnace 6: Crucible
7: Molten metal 8: Flow direction
9: Electric resistance heater 10: Insulator
11: Refractory 12: Floor Cover
13, 15, 17: Magnetic core 14, 16, 18: Coil
19, 20, 21: poles 22, 23, 24: partial electromagnetic fields
25: Electromagnetic field 30: Electromagnetic stirrer
35: Floor Stone

Claims (6)

An electromagnetic stirring device for a melting and distribution furnace of a non-ferrous high alloy alloy,
A crucible having a space for holding molten metal;
A three-phase magnetic core formed radially in a symmetrical shape on the lower side of the above crucible;
Three poles each positioned on the upper side of the three magnetic cores;
Three coils each surrounding the three poles above; and
Includes a power source that supplies a variable current to the coil;
An electromagnetic stirring device, characterized in that the molten metal is stirred by an electromagnetic field generated according to the supply of the above current. In the first paragraph,
A main frame for tiltingly mounting the above crucible; and
An electromagnetic stirring device further comprising a rail for supporting the main frame so as to be movable in a linear direction. In the first paragraph, the magnetic core
An electromagnetic stirring device comprising T-shaped magnetic cores assembled in a horizontal plane at an angle of 120 degrees to each other so that the electromagnetic field is directed to the molten metal within the crucible. In the first paragraph,
An electromagnetic stirring device in which the direction and intensity of stirring are controlled so that the molten metal is stirred in the horizontal and axial directions with respect to the crucible by the electromagnetic field generated above. In the first paragraph,
An electromagnetic stirring device in which the generated electric field is a unidirectional electromagnetic field, and the intensity of vertical toroidal melt stirring is controlled by the unidirectional electromagnetic field so that the molten metal is stirred in the axial direction with respect to the crucible. In the first paragraph,
A first mode in which the direction and intensity of stirring are controlled so that the molten metal is stirred in the horizontal and axial directions relative to the crucible by the electromagnetic field generated above;
An electromagnetic stirring device, wherein a second mode in which the intensity of vertical toroidal melt stirring is controlled is alternately used over time so that the molten metal is stirred axially with respect to the crucible by the unidirectional electromagnetic field generated above.