CN113061741A - Electroslag remelting composite device and method for improving temperature distribution of slag bath by external magnetic field - Google Patents
Electroslag remelting composite device and method for improving temperature distribution of slag bath by external magnetic field Download PDFInfo
- Publication number
- CN113061741A CN113061741A CN202110291208.3A CN202110291208A CN113061741A CN 113061741 A CN113061741 A CN 113061741A CN 202110291208 A CN202110291208 A CN 202110291208A CN 113061741 A CN113061741 A CN 113061741A
- Authority
- CN
- China
- Prior art keywords
- slag
- power supply
- composite
- crystallizer
- core rod
- 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.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/16—Remelting metals
- C22B9/18—Electroslag remelting
-
- 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Furnace Details (AREA)
Abstract
An electroslag remelting composite device and method for improving temperature distribution of a slag bath by an external magnetic field are disclosed, wherein a magnetic induction coil is arranged outside a conductive crystallizer of the device, or the magnetic induction coils are arranged outside and on the upper part of a top plate; the method comprises the following steps: pouring the molten slag into a conductive crystallizer to form a slag pool; the preheating power supply loop is communicated, and the magnetic induction coil is electrified; when the surface temperature of the core rod reaches the liquidus temperature, disconnecting the preheating power supply loop and communicating the composite power supply loop; the temperature uniformity of the surface of the core rod and the slag pool is ensured through the rotary flow of the materials in the slag pool. The device and the method of the invention increase the convenience of operation, further promote the uniformity of the circumferential temperature field and improve the uniformity of the interface bonding quality along the circumferential direction.
Description
Technical Field
The invention belongs to the technical field of metallurgy, and particularly relates to an electroslag remelting compounding device and method for improving temperature distribution of a slag bath through an external magnetic field.
Background
The roller is a key part of steel rolling equipment, bears huge extrusion stress and shearing stress in the working process, bears high cyclic stress simultaneously, and has the surface subjected to the abrasion of rolling materials and the periodic action of cooling water; the surface of the roller is always in the coupling action of thermal fatigue and mechanical fatigue during working, and the loss is very large. Due to the rapid development of the steel industry, rolling mills are continuously developing in high speed and automation direction, and the width of steel plates is also continuously increasing, so that the working conditions of the rolls are heavier. Therefore, the hot roll is required to have high surface hardness and hardenability, excellent oxidation resistance, good tempering resistance, heat conduction ability, and the like.
The traditional roller production is that a cast steel ingot obtained in a steelmaking process is forged and molded to obtain a roller blank, and finally a cold roller final product is obtained through finish machining and a heat treatment process, wherein the roll blank belongs to an integral roller. After the electroslag remelting process is generated, the electroslag remelting becomes a terminal smelting process for producing the roller, and because an electroslag remelting steel ingot has a series of advantages of fine inclusions, compact structure, low segregation degree and the like, the product quality of the roller is greatly improved. However, the integral roller prepared by electroslag remelting has segregation of alloy elements and uneven mechanical properties, and meanwhile, the alloy roller made of a single material cannot meet the dual requirements on the wear resistance and the toughness of the roller in the rolling process. For the double-alloy composite roller, as the core rod and the cladding layer can be made of different materials, the contradiction between the hardness and the toughness of the roller made of a single material can be better solved, and the production cost of the roller is greatly reduced. Therefore, the research, production and use of the bimetal composite roller become a new direction suitable for modern rolling production.
The most commonly used composite casting roller mainly has the following methods: centrifugal casting, continuous casting composite casting, spray deposition forming, hot isostatic pressing, electroslag liquid casting, and electroslag remelting. The centrifugal casting method is simple to operate, but the carbide with high density is segregated under strong centrifugal force, and cracks are easily generated in the working layer. In the electroslag remelting liquid pouring method, steel ladle single-point pouring is adopted, and the nonuniform temperature field of a cladding layer along the circumferential direction can cause nonuniform solidification quality in the circumferential direction; a composite roll with uniform interface bonding quality is obtained by rotating the slag bath. The equipment for this method is relatively complex. The process equipment and the operation are simple for preparing the composite roller by adopting the electroslag liquid pouring metal heated by a plurality of non-consumable electrodes, but the melting depth of the surface of the core rod is not uniform along the circumferential direction, the surface temperature of the core rod close to the consumable electrodes is higher, so that the melting depth of the core rod is larger, the surface temperature of the core rod in other areas is lower, and effective metallurgical bonding is difficult to form between the core rod and a cladding layer; the cost of the spray deposition forming process and the hot isostatic pressing process produces rolls with excellent mechanical properties, but the production cost is too high.
The most important components of the composite material are a composite interface, the performance of the composite roller is closely related to the interface property, whether the cladding layer is uniform and the combination of the cladding layer and the core rod is firm is the key point for the success or failure of the composite roller preparation; the single-point slag pouring causes the temperature field of the slag pool to be uneven, the temperature close to the slag pouring point is high, and the temperature of the slag pool far away from the slag pouring point is lower; after the consumable electrode is immersed in the slag bath, the electrode is not melted uniformly due to the non-uniform temperature of the slag bath, the circumferential uniformity of the interface bonding quality of the roller is poor, and the mechanical property of the roller is reduced. In addition, when the high-alloy round bar prepared by the continuous casting process is used as a consumable electrode, the uneven temperature field is caused by the joule heat unevenly distributed in the slag pool, the surface temperature of the core rod close to the consumable electrode is high, and the melting depth is large; the surface temperature of the core rod between the consumable electrodes is low, and good metallurgical bonding between the core rod and the cladding layer cannot be realized, so that the whole roller is scrapped. The conductive crystallizer technology is adopted to develop a power supply loop of an electrode-conductive crystallizer to prepare a composite roller so as to overcome the problem of excessive melting of a core rod, and a ring electrode is usually adopted in order to ensure the uniformity of the interface bonding quality along the circumferential direction during smelting and compounding. The manufacturing process of the ring electrode is complicated, whereas the high alloy ring electrode is usually prepared by centrifugal casting, which undoubtedly increases the manufacturing cost.
Disclosure of Invention
The invention aims to provide an electroslag remelting compounding device and an electroslag remelting compounding method for improving temperature distribution of a slag pool by an external magnetic field.
The electroslag remelting composite device for improving the temperature distribution of a slag pool by an external magnetic field comprises a slag melting device and a composite device, wherein the composite device comprises a conductive crystallizer, a cooling crystallizer and a dummy plate; the conductive crystallizer and the cooling crystallizer form a T-shaped conductive crystallizer; the bottom end of the conductive crystallizer and the top end of the cooling crystallizer are separated by an insulating gasket, and a liquid level detector is assembled on the side wall of the cooling crystallizer; the conductive crystallizer is connected with one pole of the composite power supply through a composite short network, and a composite heavy current switch is arranged on the composite short network; the dummy bar plate and the core rod are welded and fixed together; the outer side of the conductive crystallizer is provided with a magnetic induction coil, or the outer side of the conductive crystallizer and the upper part of the top plate are both provided with magnetic induction coils; when the other pole of the composite power supply is connected with the core rod through the composite short net, a molten slag pool is arranged in the conductive crystallizer, and the composite power supply, the composite short net, the core rod, the slag pool and the conductive crystallizer form a preheating power supply loop; when the other pole of the composite power supply is connected with the consumable electrode group through the composite short net, a molten slag pool is arranged in the conductive crystallizer, the bottom end of the consumable electrode group is inserted into the slag pool, and the composite power supply, the composite short net, the consumable electrode group, the slag pool and the conductive crystallizer form a composite power supply loop.
In the device, the slagging device consists of a graphite crucible, a graphite electrode and a slagging power supply, two poles of the slagging power supply are respectively connected with the graphite electrode and the graphite crucible through a slagging short net, a slagging large-current switch is arranged on the slagging short net, and a slag outlet is arranged on the graphite crucible.
In the device, an insulating gasket is arranged between the conductive crystallizer and the magnetic induction coil, so that the conductive crystallizer and the magnetic induction coil are insulated.
In the device, two sensor probes of the liquid level detector are arranged on the side wall of the water-cooled crystallizer, the front end face of each sensor probe is flush with the inner wall face of the water-cooled crystallizer, and the vertical height difference of the two sensor probes is 10-25 mm.
In the above device, the magnetic induction coil is powered by a magnetic induction power supply.
In the device, the current of the magnetic induction power supply, the composite power supply and the slagging power supply is direct current or alternating current.
In the above device, the magnetic induction coil is a copper ring or is made by winding N turns of copper wire.
In the device, the consumable electrode group consists of more than two consumable electrodes; the respective electrodes are uniformly distributed around the mandrel, and the distances between the respective electrodes and the mandrel are the same.
The electroslag remelting composite method for improving the temperature distribution of the slag bath by the external magnetic field adopts the device and comprises the following steps:
1. placing the core rod in a T-shaped conductive crystallizer; at the moment, the axes of the magnetic induction coil, the core rod, the conductive crystallizer and the cooling crystallizer are superposed
2. Filling magnesia and asbestos ropes in a gap between the top surface of the dummy bar plate and the bottom end of the cooling crystallizer; arranging a coating layer outside the core rod, wherein the outer wall of the coating layer is matched with the inner wall of the cooling crystallizer; the coating layer is made of asbestos cloth wrapping aluminum trioxide powder; the top surface of the coating layer is positioned between two sensor probes of the liquid level detection device;
3. assembling the consumable electrode group and the dummy electrode group together, and assembling the dummy electrode group on the lifting device;
4. melting the pre-melted slag in a slagging crucible to form molten slag; when the temperature of the molten slag is higher than the liquidus temperature by more than 150 ℃, pouring the molten slag into the conductive crystallizer to form a slag pool between the core rod and the conductive crystallizer;
5. the preheating power supply loop is communicated, the composite power supply is started, and meanwhile the magnetic induction coil is electrified and generates a magnetic field in the slag bath; under the action of the composite power supply, the temperature of the slag pool and the core rod is gradually increased; radial current flowing in the slag pool along the horizontal direction interacts with a magnetic field generated by the magnetic induction coil to generate electromagnetic force, so that materials in the slag pool rotate clockwise or anticlockwise along the circumferential direction to flow, and the temperature uniformity of the surface of the core rod and the slag pool is improved;
6. when the surface temperature of the core rod reaches the liquidus temperature, the preheating power supply loop is disconnected, the consumable electrode group is lowered through the lifting device, the consumable electrode group is inserted into the slag bath, and meanwhile, the composite power supply loop is connected; under the action of the composite power supply, the temperature of the slag pool is continuously increased, and the consumable electrode group begins to melt; when joule heat and current which are not uniformly distributed are generated in the melting process of each consumable electrode of the consumable electrode group, the temperature uniformity of the surface of the core rod and the temperature uniformity of the slag pool are ensured through the rotary flow of materials in the slag pool, and the interface combination circumferential uniformity of the cladding layer and the core rod is promoted in the subsequent compounding process;
7. forming a metal molten pool at the bottom of the slag pool along with the continuous melting of the consumable electrode; starting the ingot drawing system to enable the dummy bar plate to descend, and enabling the dummy bar plate to drive the core rod to descend; at the moment, a melting layer appears on the surface of the core rod, the metal melting pool is tightly combined with the melting layer, and a cladding layer is formed on the outer wall of the core rod; under the cooling action of the cooling crystallizer, the cladding layer is gradually solidified and combined with the core rod to form a composite casting blank;
8. controlling the melting speed of the consumable electrode by controlling the ingot drawing speed and the heating power of the composite power supply, and further controlling the liquid level of the metal molten pool to be positioned between two sensor probes of the liquid level detection device;
9. the length of the composite casting blank is continuously increased along with the proceeding of ingot drawing, and when the composite casting blank reaches the target length, the consumable electrode is lifted to be separated from the slag pool through the lifting device, so that the composite power supply loop is disconnected, and the ingot drawing is stopped at the same time; and cooling the cladding layer to normal temperature to prepare the composite steel ingot.
In the method, the pre-melted slag is dried in a resistance furnace to remove moisture, then is cooled to normal temperature along with the furnace, and then is placed in a graphite crucible of a slag melting device, and the bottom end of a graphite electrode is positioned in the pre-melted slag; heating the pre-melted slag by a slag melting power supply to form molten slag, and heating the molten slag to the liquidus temperature of more than 150 ℃; and then lifting the graphite electrode to separate the graphite electrode from the molten slag through a lifting device, and pouring the molten slag into the conductive crystallizer through a slag outlet.
In the above method, during ingot drawing, part of the aluminum trioxide powder flows out from the asbestos cloth package, and the rest part is retained in the asbestos cloth for protecting the core rod.
In the method, when the magnetic induction coil is a copper ring, the current when the magnetic induction coil is electrified is 400-1500 amperes; when the magnetic induction coil is made by winding N turns of copper wires, the current when the magnetic induction coil is electrified is 400/N-1500/N ampere.
In the method, when the current of the magnetic induction power supply and the current of the composite power supply are alternating current, the frequency of the magnetic induction power supply and the frequency of the composite power supply are the same, and the phase of the magnetic induction power supply and the phase of the composite power supply are the same.
In the method, the speed of the material in the slag pool rotating and flowing along the circumferential direction is controlled to be 5-30 r/min; the axial magnetic induction intensity generated by the magnetic induction coil is controlled by adjusting the current in the magnetic induction coil, so that the rotating flowing speed is controlled. In the preheating process and the composite process, the current in the slag pool along the radial direction and the magnetic induction intensity along the axial direction interact to generate rotary electromagnetic force, so that the slag pool rotates and flows on the horizontal plane along the circumferential direction, the circumferential convection heat transfer coefficient is increased, the uniformity of the temperature field of the slag pool is promoted, the surface temperature and the depth of a melting layer of the core rod are more uniform, and the interface bonding quality is correspondingly improved; in addition, the uniformity of a temperature field is improved by the rotary flow of the slag pool, and the cost is reduced by adopting a continuous casting high-alloy round bar which is simple to prepare and low in price as a consumable electrode.
The device and the method adopt a liquid slag starting mode, increase the convenience of operation, and increase the magnetic induction coil in the preheating process and the composite process; the magnetic induction coil generates an axial magnetic field in the slag pool, and the axial magnetic field and the radial current of the slag pool generate rotary electromagnetic force to promote the slag pool to rotate and flow; the circumferential convection heat transfer of the slag pool is increased by the rotary flow of the slag pool, so that the uniformity of a circumferential temperature field is promoted, the surface temperature and the melting depth of the core rod are very uniform, and the uniformity of the interface bonding quality along the circumferential direction is improved; in addition, the liquid level detector can dynamically monitor the position of the slag-metal interface in real time, and the use of the liquid level detector provides guarantee for reasonably adjusting the ingot drawing speed to ensure the stability of the slag-metal interface; the stability of the slag-metal interface in the composite process of composite roller smelting is a precondition for ensuring the stable operation of the whole composite roller preparation process, and is a powerful guarantee for preparing the composite steel ingot with uniform interface bonding quality and good surface quality.
Drawings
FIG. 1 is a schematic diagram of a preheating power supply circuit of a composite device according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a composite power supply circuit of the composite apparatus according to the embodiment of the present invention;
FIG. 3 is a schematic structural view of a slagging device in an embodiment of the present invention;
in the figure, 1, a composite power supply, 2, a core rod, 3, a slag bath, 4, a conductive crystallizer (an upper crystallizer), 5-1, an external magnetic induction coil I, 5-2, an external magnetic induction coil II, 6, an insulating gasket, 7, a coating layer, 8, a liquid level detector, 9, a cooling crystallizer (a lower crystallizer), 10, a composite heavy current switch, 11, a dummy bar plate, 12, a composite short net, 13, a consumable electrode group, 14, a metal molten bath, 15, a cladding layer, 16, a graphite crucible, 17, a graphite electrode, 18, molten slag, 19 and a slag hole; 20. a slagging large current switch 21, a slagging short network 22 and a slagging power supply.
Detailed Description
In the embodiment of the invention, the surface of the core rod is firstly cut to remove the skin, then the surface is coated with the antioxidant, and then the core rod is placed in the T-shaped conductive crystallizer.
In the embodiment of the invention, the axes of the magnetic induction coil, the core rod, the conductive crystallizer and the cooling crystallizer are superposed.
In the embodiment of the invention, the height of the slag pool in the conductive crystallizer is 60-80 mm.
The inner diameter of the conductive crystallizer in the embodiment of the invention is 420 mm.
The inner diameter of the lower part of the cooler crystallizer in the embodiment of the invention is 350 mm.
The model of the sensor probe of the liquid level detector in the embodiment of the invention is ML 0C-2M.
The diameter of the core rod in the embodiment of the invention is 240 mm.
The alumina powder in the examples of the present invention had a particle size of less than 1 mm.
The consumable electrode group in the embodiment of the invention consists of 24 consumable electrodes, each consumable electrode is uniformly distributed in the circumferential direction, and the diameter of each consumable electrode is 30 mm.
In the embodiment of the invention, the distance between the consumable electrode and the core rod is 10 mm.
In the embodiment of the invention, the speed of the material in the slag pool in the circumferential direction is controlled to be 5-30 r/min.
In the embodiment of the invention, N is 3-8.
Example 1
The electroslag remelting composite device for improving the temperature distribution of the slag bath by an external magnetic field comprises a slag melting device and a composite device, wherein when a power supply loop of the composite device is connected according to a preheating power supply loop, the structure is shown as a figure 1, and when the power supply loop is connected according to a composite power supply loop, the structure is shown as a figure 2;
the composite device comprises a conductive crystallizer 4, a cooling crystallizer 9 and a dummy bar plate 11; the conductive crystallizer 4 and the cooling crystallizer 9 form a T-shaped conductive crystallizer; the bottom end of the conductive crystallizer 4 is separated from the top end of the cooling crystallizer 9 by an insulating gasket 6, and a liquid level detector 8 is assembled on the side wall of the cooling crystallizer 9;
the conductive crystallizer 4 is connected with one pole of the composite power supply 1 through a composite short network 12, and a composite heavy current switch 10 is arranged on the composite short network 12;
the dummy bar plate 11 and the core rod 2 are welded and fixed together;
magnetic induction coils are arranged on the outer side of the conductive crystallizer 4 and the upper part of the top plate; wherein, the outer side is provided with an external magnetic induction coil 5-1, and the upper part is provided with an external magnetic induction coil 5-2;
when the other pole of the composite power supply 1 is connected with the core rod 2 through the composite short net 12, the conductive crystallizer 4 is internally provided with a molten slag pool 3, and the composite power supply 1, the composite short net 12, the core rod 2, the slag pool 3 and the conductive crystallizer 4 form a preheating power supply loop;
when the other pole of the composite power supply 1 is connected with the consumable electrode group 13 through the composite short net, the conductive crystallizer 4 is internally provided with a molten slag pool 3, the bottom end of the consumable electrode group 13 is inserted into the slag pool 3, and the composite power supply 1, the composite short net 12, the consumable electrode group 13, the slag pool 3 and the conductive crystallizer 4 form a composite power supply loop;
the structure of the slagging device is shown in figure 3 and comprises a graphite crucible 16, a graphite electrode 17 and a slagging power supply 22, two poles of the slagging power supply 22 are respectively connected with the graphite electrode 17 and the graphite crucible 13 through a slagging short net 21, a slagging large-current switch 20 is arranged on the slagging short net 21, and a slag outlet 19 is arranged on the graphite crucible;
insulating gaskets are arranged between the conductive crystallizer 4 and the external magnetic induction coil 5-1 and between the conductive crystallizer 4 and the external magnetic induction coil 5-2, so that the conductive crystallizer 4 and the magnetic induction coil are insulated;
two sensor probes of the liquid level detector 8 are arranged on the side wall of the water-cooled crystallizer 9, the front end face of each sensor probe is flush with the inner wall face of the water-cooled crystallizer 9, and the vertical height difference of the two sensor probes is 10-25 mm;
the magnetic induction coil is powered by a magnetic induction power supply;
the current of the magnetic induction power supply, the composite power supply 1 and the slagging power supply 22 is alternating current;
the magnetic induction coil is formed by winding 8 turns of copper wires;
the consumable electrodes in the consumable electrode group 13 are uniformly distributed around the mandrel 2;
the method comprises the following steps:
the adopted pre-melted slag comprises CaF according to the mass percentage2 50％，CaO 17％，Al2O3 25％，MgO 3％，SiO25% with a liquidus temperature of 1271 ℃;
the adopted core rod 2 is made of 42CrMo, and the liquidus temperature is 1487 ℃;
the consumable electrode is made of Cr5, and the melting temperature is 1465 ℃;
placing the core rod 2 in a T-shaped conductive crystallizer; at the moment, the axes of the magnetic induction coil, the core rod 2, the conductive crystallizer 4 and the cooling crystallizer 9 are superposed;
filling magnesia and asbestos ropes in a gap between the top surface of the dummy bar plate 11 and the bottom end of the cooling crystallizer 9; a coating layer 7 is arranged outside the core rod 2, and the outer wall of the coating layer 7 is matched with the inner wall of a cooling crystallizer 9; the coating layer 7 is made of asbestos cloth wrapping aluminum trioxide powder; the top surface of the coating layer 7 is positioned between two sensor probes of the liquid level detection device 8;
assembling the consumable electrode group 13 and the dummy electrode group together, and assembling the dummy electrode group on the lifting device;
the pre-melted slag is dried in a resistance furnace to remove moisture, then is cooled to normal temperature along with the furnace, and is then placed in a graphite crucible 16 of a slag melting device, and the bottom end of a graphite electrode 17 is positioned in the pre-melted slag; heating the pre-melted slag by a slagging power supply 22 to form molten slag 18, and heating the molten slag 18 to the liquidus temperature of 150 ℃; then, the graphite electrode 17 is lifted by a lifting device to be separated from the slag 18, and the slag 18 is poured into the conductive crystallizer 4 through a slag outlet 19 to form a slag pool 3 between the core rod 2 and the conductive crystallizer 4;
the preheating power supply loop is communicated, the composite power supply 1 is started (the composite power supply switch is switched on), meanwhile, the magnetic induction coil is electrified, and the magnetic induction coil generates a magnetic field in the slag bath 3; under the action of the composite power supply 1, the temperature of the slag pool 3 and the core rod 2 is gradually increased; the radial current flowing in the slag pool 3 along the horizontal direction interacts with the magnetic field generated by the magnetic induction coil to generate electromagnetic force, so that the material in the slag pool 3 rotates clockwise along the circumferential direction to flow, and the temperature uniformity of the surface of the core rod 2 and the slag pool 3 is further improved;
the current of the magnetic induction coil is 800/8-100A; the frequency and the phase of the magnetic induction power supply and the composite power supply are the same;
when the surface temperature of the core rod 2 reaches the liquidus temperature, the preheating power supply loop is disconnected, the consumable electrode group 13 is lowered through the lifting device, the consumable electrode group 13 is inserted into the slag bath 3, and meanwhile, the composite power supply loop is connected; under the action of the composite power supply 1, the temperature of the slag pool 3 is continuously increased, and the consumable electrode group 13 starts to melt; when joule heat and current which are not uniformly distributed are generated in the melting process of each consumable electrode of the consumable electrode group 13, the temperature uniformity of the surface of the core rod 2 and the temperature uniformity of the slag pool 3 are ensured through the rotary flow of materials in the slag pool 3, and the interface combination circumferential uniformity of the cladding layer 15 and the core rod 2 is promoted in the subsequent compounding process;
with the continuous melting of the consumable electrode, a metal molten pool 14 is formed at the bottom of the slag pool 3; starting the ingot drawing system to enable the dummy bar plate 11 to descend, and enabling the dummy bar plate 11 to drive the core rod 2 to descend; at the moment, a melting layer appears on the surface of the core rod, the metal melting pool 14 is tightly combined with the melting layer, and a cladding layer 15 is formed on the outer wall of the core rod 2; under the cooling action of the cooling crystallizer 9, the cladding layer 15 is gradually solidified and combined with the core rod 2 to form a composite casting blank;
during ingot drawing, part of the aluminum trioxide powder flows out from the asbestos cloth package, and the rest part of the aluminum trioxide powder is remained in the asbestos cloth to protect the core rod;
controlling the ingot-drawing speed and the melting speed of the consumable electrode group 13 by the heating power of the composite power supply 1, and further controlling the liquid level of the molten metal pool 14 to be positioned between two sensor probes of the liquid level detection device 8;
the length of the composite casting blank is continuously increased along with the proceeding of ingot drawing, and when the composite casting blank reaches the target length, the consumable electrode is lifted to the slag separating pool 3 through the lifting device, so that the composite power supply loop is disconnected, and the ingot drawing is stopped at the same time; cooling the cladding layer 15 to normal temperature to prepare a composite steel ingot;
the composite steel ingot is a composite roller made of Cr5-42CrMo, the interface has no defects of air holes, inclusions, cracks and the like, the depth of a fusion layer in the circumferential direction is consistent and uniform, and the quality of the composite interface is good.
Example 2
The device structure is the same as that of embodiment 1;
the method is the same as example 1, except that:
the number of turns of the magnetic induction coil is 5; the current of the magnetic induction coil is 1500/5-300A;
the composite steel ingot is a composite roller made of Cr5-42CrMo, the interface has no defects of air holes, inclusions, cracks and the like, the depth of a fusion layer in the circumferential direction is consistent and uniform, and the quality of the composite interface is good.
Example 3
The device structure is the same as that of embodiment 1;
the method is the same as example 1, except that:
the number of turns of the magnetic induction coil is 3; the current of the magnetic induction coil is 400/3-133A;
the composite steel ingot is a composite roller made of Cr5-42CrMo, the interface has no defects of air holes, inclusions, cracks and the like, the depth of a fusion layer in the circumferential direction is consistent and uniform, and the quality of the composite interface is good.
Comparative example 1
By adopting the same device as the embodiment 1, when the composite power supply loop is communicated, the magnetic induction coil is powered off; as a result, the surface interface bonding quality of the composite steel ingot is poor, and a small amount of defects such as air holes, inclusions, cracks and the like exist; the composite interfacial bond quality is not uniform circumferentially.
Comparative example 2
By adopting the same device as the embodiment 1, when the preheating power supply loop is communicated, the magnetic induction coil is powered off; when the composite power supply loop is communicated, the magnetic induction coil is powered; the temperature field of the slag pool is unevenly distributed along the circumferential direction in the preheating process; in the composite smelting process, the temperature field of the slag pool is not uniform along the circumferential direction, and the conductivity of the slag pool is not uniformly distributed along the circumferential direction; the temperature field of the slag bath is not uniform, and the melting depth of the consumable electrode is not uniform, so that the composite smelting process is stopped.
Comparative example 3
The same device as in example 1 was used, and the current supplied to the magnetic induction coil was 100/8 ═ 12.5A; the temperature of the slag pool is still unevenly distributed along the circumferential direction in the preheating process due to the small current; in the compounding process, the consumable electrode group is not melted uniformly, the temperature close to the slag pouring point is high, and the melting speed of the consumable electrode is high; the temperature far away from the slag pouring point is low, and the melting speed of the consumable electrode is low; eventually causing the process to stop.
Comparative example 4
The same device as in example 1 was used, and the current supplied to the magnetic induction coil was 2000/8 ═ 250A; because the current is large, the slag pool flows anticlockwise in the preheating and compounding processes, the circumferential flow enhances the circumferential flow heat exchange coefficient, and the consumable electrode is promoted to be melted uniformly; the rotating speed of the slag pool is too fast, the effective heat conductivity of the slag pool is increased, so that the heat transferred from the slag pool to the core rod is too much, the melting depth of the surface of the core rod is larger, the content of alloy elements of the cladding layer is diluted, and the mechanical property of the final composite steel ingot is reduced.
Claims (9)
1. An electroslag remelting composite device with an external magnetic field for improving temperature distribution of a slag bath is characterized by comprising a slag melting device and a composite device, wherein the composite device comprises a conductive crystallizer, a cooling crystallizer and a dummy plate; the conductive crystallizer and the cooling crystallizer form a T-shaped conductive crystallizer; the bottom end of the conductive crystallizer and the top end of the cooling crystallizer are separated by an insulating gasket, and a liquid level detector is assembled on the side wall of the cooling crystallizer; the conductive crystallizer is connected with one pole of the composite power supply through a composite short network, and a composite heavy current switch is arranged on the composite short network; the dummy bar plate and the core rod are welded and fixed together; the outer side of the conductive crystallizer is provided with a magnetic induction coil, or the outer side of the conductive crystallizer and the upper part of the top plate are both provided with magnetic induction coils; when the other pole of the composite power supply is connected with the core rod through the composite short net, a molten slag pool is arranged in the conductive crystallizer, and the composite power supply, the composite short net, the core rod, the slag pool and the conductive crystallizer form a preheating power supply loop; when the other pole of the composite power supply is connected with the consumable electrode group through the composite short net, a molten slag pool is arranged in the conductive crystallizer, the bottom end of the consumable electrode group is inserted into the slag pool, and the composite power supply, the composite short net, the consumable electrode group, the slag pool and the conductive crystallizer form a composite power supply loop.
2. The electroslag remelting combination device with the external magnetic field for improving the temperature distribution of the slag bath according to claim 1, wherein the slagging device comprises a graphite crucible, a graphite electrode and a slagging power supply, two poles of the slagging power supply are respectively connected with the graphite electrode and the graphite crucible through a slagging short net, a slagging large current switch is arranged on the slagging short net, and a slag outlet is arranged on the graphite crucible.
3. The electroslag remelting combination device with the external magnetic field for improving the temperature distribution of the slag bath according to claim 1, wherein an insulating gasket is arranged between the conductive crystallizer and the magnetic induction coil to insulate the conductive crystallizer from the magnetic induction coil.
4. The electroslag remelting composite device with the external magnetic field for improving the temperature distribution of the slag bath according to claim 1, wherein the two sensor probes of the liquid level detector are installed on the side wall of the water-cooled crystallizer, the front end surface of each sensor probe is flush with the inner wall surface of the water-cooled crystallizer, and the vertical height difference of the two sensor probes is 10-25 mm.
5. The electroslag remelting composite device with an external magnetic field for improving the temperature distribution of a slag bath according to claim 1, wherein the magnetic induction coil is powered by a magnetic induction power supply; the current of the magnetic induction power supply, the composite power supply and the slagging power supply is direct current or alternating current.
6. An electroslag remelting compounding method for improving temperature distribution of a slag bath by an external magnetic field is characterized in that the device of claim 1 is adopted, and the method is carried out according to the following steps:
(1) placing the core rod in a T-shaped conductive crystallizer; at the moment, the axes of the magnetic induction coil, the core rod, the conductive crystallizer and the cooling crystallizer are superposed
(2) Filling magnesia and asbestos ropes in a gap between the top surface of the dummy bar plate and the bottom end of the cooling crystallizer; arranging a coating layer outside the core rod, wherein the outer wall of the coating layer is matched with the inner wall of the cooling crystallizer; the coating layer is made of asbestos cloth wrapping aluminum trioxide powder; the top surface of the coating layer is positioned between two sensor probes of the liquid level detection device;
(3) assembling the consumable electrode group and the dummy electrode group together, and assembling the dummy electrode group on the lifting device;
(4) melting the pre-melted slag in a slagging crucible to form molten slag; when the temperature of the molten slag is higher than the liquidus temperature by more than 150 ℃, pouring the molten slag into the conductive crystallizer to form a slag pool between the core rod and the conductive crystallizer;
(5) the preheating power supply loop is communicated, the composite power supply is started, and meanwhile the magnetic induction coil is electrified and generates a magnetic field in the slag bath; under the action of the composite power supply, the temperature of the slag pool and the core rod is gradually increased; radial current flowing in the slag pool along the horizontal direction interacts with a magnetic field generated by the magnetic induction coil to generate electromagnetic force, so that materials in the slag pool rotate clockwise or anticlockwise along the circumferential direction to flow, and the temperature uniformity of the surface of the core rod and the slag pool is improved;
(6) when the surface temperature of the core rod reaches the liquidus temperature, the preheating power supply loop is disconnected, the consumable electrode group is lowered through the lifting device, the consumable electrode group is inserted into the slag bath, and meanwhile, the composite power supply loop is connected; under the action of the composite power supply, the temperature of the slag pool is continuously increased, and the consumable electrode group begins to melt; when joule heat and current which are not uniformly distributed are generated in the melting process of each consumable electrode of the consumable electrode group, the temperature uniformity of the surface of the core rod and the temperature uniformity of the slag pool are ensured through the rotary flow of materials in the slag pool, and the interface combination circumferential uniformity of the cladding layer and the core rod is promoted in the subsequent compounding process;
(7) forming a metal molten pool at the bottom of the slag pool along with the continuous melting of the consumable electrode; starting the ingot drawing system to enable the dummy bar plate to descend, and enabling the dummy bar plate to drive the core rod to descend; at the moment, a melting layer appears on the surface of the core rod, the metal melting pool is tightly combined with the melting layer, and a cladding layer is formed on the outer wall of the core rod; under the cooling action of the cooling crystallizer, the cladding layer is gradually solidified and combined with the core rod to form a composite casting blank;
(8) controlling the melting speed of the consumable electrode by controlling the ingot drawing speed and the heating power of the composite power supply, and further controlling the liquid level of the metal molten pool to be positioned between two sensor probes of the liquid level detection device;
(9) the length of the composite casting blank is continuously increased along with the proceeding of ingot drawing, and when the composite casting blank reaches the target length, the consumable electrode is lifted to be separated from the slag pool through the lifting device, so that the composite power supply loop is disconnected, and the ingot drawing is stopped at the same time; and cooling the cladding layer to normal temperature to prepare the composite steel ingot.
7. The electroslag remelting compounding method for improving the temperature distribution of the slag bath by using the external magnetic field according to claim 6, wherein in the step (4), the pre-melted slag is dried in a resistance furnace to remove moisture, then is cooled to normal temperature along with the furnace, and is then placed in a graphite crucible of a slagging device, wherein the bottom end of a graphite electrode is positioned in the pre-melted slag; heating the pre-melted slag by a slag melting power supply to form molten slag, and heating the molten slag to the liquidus temperature of more than 150 ℃; and then lifting the graphite electrode to separate the graphite electrode from the molten slag through a lifting device, and pouring the molten slag into the conductive crystallizer through a slag outlet.
8. The electroslag remelting compounding method for improving the temperature distribution of a slag bath by using an external magnetic field according to claim 6, wherein in the step (5), when the magnetic induction coil is a copper ring, the current when the magnetic induction coil is electrified is 400-1500A; when the magnetic induction coil is made by winding N turns of copper wires, the current when the magnetic induction coil is electrified is 400/N-1500/N ampere.
9. The electroslag remelting compounding method for improving the temperature distribution of a slag bath by using an external magnetic field according to claim 6, wherein in the step (5), when the currents fed into the magnetic induction power supply and the compound power supply are alternating currents, the frequency and the phase of the magnetic induction power supply and the compound power supply are the same.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110291208.3A CN113061741B (en) | 2021-03-18 | 2021-03-18 | Electroslag remelting composite device and method for improving temperature distribution of slag bath by external magnetic field |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110291208.3A CN113061741B (en) | 2021-03-18 | 2021-03-18 | Electroslag remelting composite device and method for improving temperature distribution of slag bath by external magnetic field |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113061741A true CN113061741A (en) | 2021-07-02 |
| CN113061741B CN113061741B (en) | 2022-05-03 |
Family
ID=76562283
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110291208.3A Active CN113061741B (en) | 2021-03-18 | 2021-03-18 | Electroslag remelting composite device and method for improving temperature distribution of slag bath by external magnetic field |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113061741B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114603118A (en) * | 2022-03-08 | 2022-06-10 | 朱龙华 | Equipment and process for electroslag smelting casting, build-up welding and composite (re) manufacturing of metal roller |
| CN114619019A (en) * | 2022-03-08 | 2022-06-14 | 朱龙华 | Equipment and process for compositely (re) manufacturing metallurgical roller by electroslag remelting and surfacing |
| CN114653926A (en) * | 2022-03-11 | 2022-06-24 | 东北大学 | Device and method for preparing composite roller by electroslag remelting method with crystallizer added with magnetic field |
| CN114854994A (en) * | 2022-03-15 | 2022-08-05 | 东北大学 | Device and method for preparing composite steel ingot based on conductive crystallizer |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5462572A (en) * | 1992-08-07 | 1995-10-31 | Asea Brown Boveri Ab | Method and a device for stirring a molten metal |
| US20100163207A1 (en) * | 2007-08-03 | 2010-07-01 | Forschungszentrum Dresden-Rossendorf E. V. | Method and device for the electromagnetic stirring of electrically conductive fluids |
| CN103056344A (en) * | 2013-01-18 | 2013-04-24 | 上海大学 | Method for controlling electroslag melting casting by added transient magnetic field and electroslag smelting casting device |
| CN203639530U (en) * | 2013-01-11 | 2014-06-11 | 上海大学 | Composite electroslag casting device for optimizing metal solidification structure by using steady-state magnetic field |
| CN203649368U (en) * | 2013-11-18 | 2014-06-18 | 上海大学 | Electro-slag smelting casting device with applied magnetic field |
| CN104388689A (en) * | 2014-11-28 | 2015-03-04 | 中国科学院金属研究所 | Method and device for casting electromagnetic compound control electroslag remelting fine grains |
| CN104827007A (en) * | 2015-04-16 | 2015-08-12 | 上海大学 | Large-scale uniform-structure alloy ingot continuous casting preparation method and magnetic control electroslag continuous casting device |
| CN108372286A (en) * | 2018-03-29 | 2018-08-07 | 东北大学 | A kind of electroslag remelting process prepares the device and method of bimetallic composite roll |
| CN209412282U (en) * | 2018-11-30 | 2019-09-20 | 浙江正达模具有限公司 | A kind of electromagnetic stirring mould |
-
2021
- 2021-03-18 CN CN202110291208.3A patent/CN113061741B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5462572A (en) * | 1992-08-07 | 1995-10-31 | Asea Brown Boveri Ab | Method and a device for stirring a molten metal |
| US20100163207A1 (en) * | 2007-08-03 | 2010-07-01 | Forschungszentrum Dresden-Rossendorf E. V. | Method and device for the electromagnetic stirring of electrically conductive fluids |
| CN203639530U (en) * | 2013-01-11 | 2014-06-11 | 上海大学 | Composite electroslag casting device for optimizing metal solidification structure by using steady-state magnetic field |
| CN103056344A (en) * | 2013-01-18 | 2013-04-24 | 上海大学 | Method for controlling electroslag melting casting by added transient magnetic field and electroslag smelting casting device |
| CN203649368U (en) * | 2013-11-18 | 2014-06-18 | 上海大学 | Electro-slag smelting casting device with applied magnetic field |
| CN104388689A (en) * | 2014-11-28 | 2015-03-04 | 中国科学院金属研究所 | Method and device for casting electromagnetic compound control electroslag remelting fine grains |
| CN104827007A (en) * | 2015-04-16 | 2015-08-12 | 上海大学 | Large-scale uniform-structure alloy ingot continuous casting preparation method and magnetic control electroslag continuous casting device |
| CN108372286A (en) * | 2018-03-29 | 2018-08-07 | 东北大学 | A kind of electroslag remelting process prepares the device and method of bimetallic composite roll |
| CN209412282U (en) * | 2018-11-30 | 2019-09-20 | 浙江正达模具有限公司 | A kind of electromagnetic stirring mould |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114603118A (en) * | 2022-03-08 | 2022-06-10 | 朱龙华 | Equipment and process for electroslag smelting casting, build-up welding and composite (re) manufacturing of metal roller |
| CN114619019A (en) * | 2022-03-08 | 2022-06-14 | 朱龙华 | Equipment and process for compositely (re) manufacturing metallurgical roller by electroslag remelting and surfacing |
| CN114619019B (en) * | 2022-03-08 | 2023-06-23 | 朱龙华 | Equipment and process for manufacturing metallurgical roller by electroslag remelting and surfacing compound (re) method |
| CN114603118B (en) * | 2022-03-08 | 2023-06-23 | 朱龙华 | Equipment and process for manufacturing metal roller by electroslag casting and surfacing compound (re) method |
| CN114653926A (en) * | 2022-03-11 | 2022-06-24 | 东北大学 | Device and method for preparing composite roller by electroslag remelting method with crystallizer added with magnetic field |
| CN114854994A (en) * | 2022-03-15 | 2022-08-05 | 东北大学 | Device and method for preparing composite steel ingot based on conductive crystallizer |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113061741B (en) | 2022-05-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113061741B (en) | Electroslag remelting composite device and method for improving temperature distribution of slag bath by external magnetic field | |
| CN108372286B (en) | A kind of electroslag remelting process prepares the device and method of bimetallic composite roll | |
| EP0662361B1 (en) | Die casting method and die casting machine | |
| CN108746562B (en) | Device and method for preparing large composite steel ingot by graphite electrode ring preheating electroslag casting | |
| CN107262686B (en) | A kind of device and method preparing compound steel ingot | |
| CN111590054B (en) | Device and method for preparing bimetal clad roller by ingot drawing type electroslag remelting method | |
| CN113547102B (en) | Device and method for preparing large steel ingot by conductive crystallizer electroslag remelting method | |
| CN105522126B (en) | The compound roll shaft manufacturing process of high-performance and equipment | |
| CN102601325A (en) | Method for preparing copper-aluminum composite bar by means of horizontally continuous casting | |
| CN106111931A (en) | A kind of metal clad material solid-liquid continuous casting composite forming apparatus and process | |
| JP2022501198A (en) | Bearing body anti-friction layer copper alloy filling device and bearing body Bimetal composite material manufacturing method | |
| US6758259B1 (en) | Method and arangement for producing casting moulds from metal | |
| Park et al. | Continuous casting of steel billet with high frequency electromagnetic field | |
| JP3949208B2 (en) | Metal remelting method and apparatus used for manufacturing continuous casting | |
| CN108436047B (en) | Resultant field prepares the device and method of big specification fine grain homogeneous aluminium alloy cast ingot | |
| CN113426970A (en) | Vertical semi-continuous production device and production process of large round billets with phi of 1000 mm-2000 mm | |
| CN114854994B (en) | Device and method for preparing composite steel ingot based on conductive crystallizer | |
| CA1198157A (en) | Casting technique for lead storage battery grids | |
| US5193607A (en) | Method for precision casting of titanium or titanium alloy | |
| US3978907A (en) | Method of electroslag remelting by melting main and additional electrodes and machine for effecting said method | |
| CN109128103B (en) | Device and method for preparing composite roller/composite steel ingot by electroslag casting method | |
| CN2356783Y (en) | Device for molten metal electroslag continuous casting ingot and pile-up welding | |
| CN114653926A (en) | Device and method for preparing composite roller by electroslag remelting method with crystallizer added with magnetic field | |
| CN203235929U (en) | Induction heating and electromagnetic stirring device for riser of steel ingot | |
| JP5203680B2 (en) | Metal electroslag remelting process and ingot mold used therefor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |