Electromagnetic purifying device for inclusions in the industrial production process of die-casting zinc alloy and method thereof

Abstract

The application discloses a device and method for electromagnetic purification of inclusions in the industrial production process of die-casting zinc alloy, and adds a tundish before the die-casting zinc alloy ingot is poured, drives the die-casting zinc alloy melt to flow by using the electromagnetic force generated by an electromagnetic stirring coil, realizes continuous stirring in sequence through the opening at the lower part of the tundish with filter cloth, drives the inclusions with large density difference from the zinc melt to the outer wall of the tundish by using centrifugal force to form zinc alloy slag, and finally removes the zinc alloy slag on the outer wall and the filter cloth through the way of cleaning the furnace and removing slag, so that the high-efficiency electromagnetic separation of various inclusions in the zinc alloy melt is realized. The device is simple and easy to operate, and is not only suitable for the continuous industrial production of traditional die-casting zinc alloy, but also suitable for the purification of inclusions of various alloys, semiconductor melts and other non-ferrous alloys, and is also suitable for the purification of special steel and high-quality steel melts, and is also suitable for the concentration and enrichment of valuable phases in lava and slag.

Description

Technical Field

[0001] This invention relates to the field of die-cast zinc alloy smelting and preparation, and specifically to a method for efficiently removing inclusions using electromagnetic purification technology during the industrial production of die-cast zinc alloys. Background Technology

[0002] Die-cast zinc alloys are alloys composed of zinc as the base metal with the addition of elements such as aluminum, copper, and magnesium. Die-cast zinc alloys possess advantages such as low melting point, good fluidity, easy melting and welding, and plastic processing, as well as corrosion resistance in the atmosphere. They are commonly used in the production of various toys, household goods, and automotive parts. With the rapid development of my country's automotive, construction, and furniture industries, the demand for die-cast zinc alloys is showing a rapid growth trend. The traditional industrial production process for die-cast zinc alloys involves: electrolytic zinc sheets passing through a melting furnace, alloying furnace, holding furnace, and casting chute, and finally being cast into a mold. During this process, various inclusions inevitably form in the zinc alloy melt, such as oxide inclusions formed by reaction with oxygen in the air, iron-zinc intermetallic compounds, refractory material flaking, and foreign inclusions. These inclusions vary in size and morphology, and all exist as independent phases in the die-cast zinc alloy, significantly affecting the mechanical, physical, and chemical properties of the zinc alloy.

[0003] Common methods for removing inclusions from liquid metals include filtration, settling, air blowing, and flux refining. However, these methods generally suffer from problems such as unstable purification effects, high requirements for flow rate stability, small processing capacity, decreased purification efficiency over time, and difficulty in treating waste slag and used flux, causing environmental pollution. Given the smelting characteristics of die-cast zinc alloys, most inclusions have relatively low density and stable chemical properties, making them difficult to separate using remelting or chemical treatment methods. The size, morphology, distribution, and interaction of these inclusions with the alloy significantly affect its mechanical, physical, and chemical properties. Traditional inclusion removal methods such as filtration and settling are unsuitable for zinc dross removal, necessitating the exploration of a more effective zinc dross removal method. Summary of the Invention

[0004] To address the problems of existing technologies, the present invention aims to overcome the shortcomings of existing technologies and provide an electromagnetic purification device and method for inclusions in the die-cast zinc alloy industrial production process. Utilizing electromagnetic stirring and separation technology, various inclusions in die-cast zinc alloys can be efficiently removed under suitable electromagnetic parameters. Furthermore, this method has advantages such as short processing time, convenient control, and simple equipment.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0006] An electromagnetic purification device for inclusions in the industrial production of die-cast zinc alloys is an integrated production equipment consisting of a smelting unit, a purification unit, and a casting unit.

[0007] The smelting apparatus is a reverberatory furnace, which is equipped with a furnace opening, a resistance band, a type K thermocouple, and a bottom pouring channel.

[0008] The purification process employs an intermediate ladle, which is equipped with a resistance band, a type K thermocouple, an electromagnetic stirring coil, and a filter cloth. The intermediate ladle is positioned between the bottom pouring channel of the reverberatory furnace in the smelting unit and the casting unit, thus setting up the purification process before the melt is cast into ingots. During the smelting process, the die-cast zinc alloy melt obtained from the smelting reacts with oxygen to form inclusions. The purification process is then implemented using the aforementioned purification device to remove these inclusions from the alloy melt through an electromagnetic purification process.

[0009] The casting device includes iron molds and a conveyor belt; a series of iron molds are arranged sequentially on the conveyor belt for transport.

[0010] During the electromagnetic purification of inclusions in the industrial production of die-cast zinc alloy, an electrolytic zinc plate is added into a reverberatory furnace through the furnace opening. Direct current is passed through the resistance band, and the electrolytic zinc plate is melted into zinc melt through radiative heat transfer. Then, an intermediate alloy ingot is added into the reverberatory furnace through the furnace opening to achieve alloying. The resulting die-cast zinc alloy melt with the required composition is then held at a temperature. This heating process is temperature-controlled by a type K thermocouple.

[0011] Direct current is passed through a resistance band above the tundish to heat it. This heating process is also temperature-controlled by a type K thermocouple to prevent the zinc alloy melt from solidifying. The die-cast zinc alloy melt is then poured into the tundish through the bottom gating channel of the reverberatory furnace. Alternating current is passed through an electromagnetic stirring coil located on the outside or bottom of the tundish. The electromagnetic force generated by the electromagnetic stirring coil drives the flow of the die-cast zinc alloy melt. The tundish forms different connected areas through partitions. The filter cloth located in the lower part of the partition of adjacent areas of the tundish is used to achieve continuous stirring. Centrifugal force drives the inclusions to the side wall of the tundish and enriches them, forming zinc alloy slag. Finally, the zinc alloy slag on the outer wall of the tundish and on the filter cloth is removed by furnace cleaning / slag removal, thereby purifying the alloy melt.

[0012] The purified zinc alloy melt is poured into an iron mold for solidification, thus cooling and forming the die-cast zinc alloy into zinc alloy ingots; the conveyor belt is turned on to realize the continuous implementation of the die-cast zinc alloy melting and casting process.

[0013] Preferably, during the electromagnetic purification process, the die-cast zinc alloy melt in the tundish is repeatedly purified through the opening of the filter cloth at the bottom of the tundish.

[0014] Preferably, the tundish includes at least two tundishes connected in sequence, with adjacent tundishes connected by a flow channel with an opening for filter cloth. The die-cast zinc alloy melt is poured into the first tundish through the bottom gating channel of the reverberatory furnace; then it enters the next tundish through the opening for filter cloth, and the zinc alloy melt processed in the last tundish is poured into the iron mold through the rear gating channel.

[0015] Preferably, the tundish includes two tundishes connected in sequence, a first tundish and a second tundish, which are connected by a flow channel with an opening for filter cloth. The die-casting zinc alloy molten material is poured into the first tundish through the bottom gating channel of the reverberatory furnace; then it enters the second tundish through the opening in the filter cloth. The zinc alloy molten material treated in the second tundish is poured into the iron mold through a rear gating channel. The zinc alloy molten material is poured into the tundish used for electromagnetic purification treatment. The tundish is divided into two parts, with the lower part having interconnected openings. A type K thermocouple is inserted in the upper part. Direct current is passed through the resistance band on the upper side of the tundish, and the zinc alloy molten material is kept warm through radiative heat transfer. The heat preservation process is controlled by the type K thermocouple. An alternating current is passed through the electromagnetic stirring coil at the bottom of the tundish, and the zinc alloy melt is driven to flow by electromagnetic force. The melt is continuously stirred through the opening at the bottom of the tundish. A filter cloth is placed at the opening to filter the melt and collect oxide slag. Centrifugal force is used to drive the inclusions to the outer wall of the tundish to accumulate and form zinc alloy slag. Finally, the alloy slag on the furnace wall and the filter cloth is removed by furnace cleaning / slag removal. This process can be repeated through the central opening, thereby achieving multiple purification of the die-cast zinc alloy melt.

[0016] Preferably, the resistance band used as the heating source of the reverberatory furnace can be set on the side or bottom of the furnace to provide resistance heating; the resistance heating method can also be replaced by natural gas heating or induction heating through an induction heating coil.

[0017] Preferably, the intermediate package can be made of graphite or other carbon materials.

[0018] A method for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process, utilizing the electromagnetic purification device for inclusions in the die-cast zinc alloy industrial production process described in this invention, includes the following steps:

[0019] Step 1: Preparation of raw materials and equipment:

[0020] Electrolytic zinc plates are placed into a reverberatory furnace through the furnace opening, and direct current is passed through the resistance band at the top of the furnace. The electrolytic zinc plates are melted into zinc molten material through radiant heat transfer and held at a constant temperature. This heating process is controlled by a type K thermocouple. Subsequently, intermediate alloy ingots are added into the reverberatory furnace through the furnace opening to achieve alloying, melting and preparing a die-casting zinc alloy molten material with the required composition, and then waiting for casting. This completes the melting and holding of the die-casting zinc alloy.

[0021] Step 2, Electromagnetic purification process:

[0022] Direct current is passed through the resistance band on the tundish to heat it. This heating process is also controlled by a type K thermocouple. Then, the die-cast zinc alloy molten material is poured into the tundish through the bottom pouring channel of the reverberatory furnace. Alternating current is passed through the electromagnetic stirring coil at the bottom of the tundish. The electromagnetic force generated by the electromagnetic stirring coil drives the zinc alloy molten material through the opening with filter cloth in the lower part of the tundish to achieve continuous stirring. Centrifugal force drives the inclusions to the side wall of the tundish to accumulate and form zinc alloy slag. Finally, the alloy slag on the outer wall and on the filter cloth is removed by furnace cleaning / slag removal, thus purifying the molten material. The electromagnetic purification process can be repeated through the opening with filter cloth at the bottom of the tundish, thereby achieving multiple purifications of the zinc alloy molten material.

[0023] Step 3, Continuous casting process:

[0024] The purified zinc alloy melt is poured into an iron mold to cool and form the die-cast zinc alloy into zinc alloy ingots. The conveyor belt is then turned on to make the die-cast zinc alloy melting and casting process continuous.

[0025] Preferably, the degree of inclusion removal can be controlled by changing the current intensity, current frequency, and stirring time of the alternating current supplied to the electromagnetic stirring coil. The alternating current intensity supplied to the electromagnetic stirring coil is 0-10000A, the frequency is 0.01Hz-1000Hz, and the stirring time is 0.01-100 hours. More preferably, the current range is 0-50A, the current frequency is 1Hz-100Hz, and the stirring time is 0.01-0.5 hours. The optimal electromagnetic parameters are a stirring current of 30A, a stirring frequency of 25Hz, and a stirring time of 5 minutes.

[0026] Preferably, the direct current passed through the resistance band serving as the electric heating device has a current intensity of no more than 50,000 A. More preferably, the current range is 500-10,000 A.

[0027] Preferably, the method for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process of the present invention is applicable to the production of any type of die-cast zinc alloy ingot, including round billets, square billets, slab billets, tube billets, and irregular-shaped billets.

[0028] Preferably, the method for electromagnetic purification of inclusions in the industrial production of die-cast zinc alloys of the present invention is applicable to different grades of die-cast zinc alloys, including at least one of Zamak 2, Zamak 3, Zamak 4, Zamak 5, Zamak 7, ZA-8, ZA-12, and ZA-27.

[0029] Preferably, the method for electromagnetic purification of inclusions in the industrial production process of die-cast zinc alloys of the present invention is not limited to electromagnetic purification in die-cast zinc alloys, but is also suitable for hot-dip galvanized alloys, aluminum and its alloys, magnesium and its alloys, tin and its alloys, copper and its alloys, gallium and its alloys, indium and its alloys, antimony and its alloys, bismuth and its alloys, semiconductor melts and other non-ferrous alloys, as well as the purification of melts such as special steels and high-quality steels, and is also suitable for the concentration and enrichment process of valence phases in lava and slag.

[0030] Preferably, the direct current passed through the resistance band, which serves as an electric heating device, has a current intensity of 0-50000A.

[0031] This invention provides an electromagnetic purification device for inclusions in the industrial production of die-cast zinc alloys. Direct current is applied to a resistance band at the top of a reverberatory furnace to melt the electrolytic zinc plate raw material, forming a zinc melt. Temperature is controlled by a type K thermocouple during the heating process. Subsequently, an intermediate alloy ingot is added to the reverberatory furnace through the furnace opening to melt and maintain the temperature of the die-cast zinc alloy. The molten die-cast zinc alloy is then poured into an tundish with an opening at the bottom, which divides the tundish into two interconnected parts. Direct current is also applied to the resistance band at the top of the tundish, maintaining the temperature of the zinc alloy melt through radiative heat transfer. This temperature maintenance is also controlled by a type K thermocouple inserted in the tundish to prevent solidification. Finally, alternating current is applied to an electromagnetic stirring coil at the bottom of the tundish to induce rotation of the die-cast zinc alloy melt within the tundish. The generated electromagnetic force drives the zinc melt to flow, and it is continuously stirred through an opening with a filter cloth at the bottom of the tundish. Centrifugal force drives inclusions with a large density difference from the zinc melt to the outer wall of the tundish, where they accumulate and form zinc alloy slag. Finally, the alloy slag on the outer wall and the filter cloth is removed by furnace cleaning / slag removal. This electromagnetic purification process of the die-casting zinc alloy melt can be repeated through the opening at the bottom of the tundish, thus achieving multiple purifications of the zinc alloy melt. Finally, the purified die-casting zinc alloy melt in the tundish is poured into an iron mold and solidified into zinc ingots. Using a conveyor belt, the rapid and continuous industrial production of zinc alloy ingots can be achieved.

[0032] Compared with the prior art, the present invention has the following obvious and prominent substantive features and significant advantages:

[0033] 1. The method and apparatus of the present invention add a magnetically controlled tundish purification device at the end of the gating channel of the reverberatory heating furnace. The electromagnetic stirring coil installed outside the tundish drives the die-cast zinc alloy melt in the tundish to be stirred continuously in sequence. The centrifugal force generated is used to separate the inclusions to the outer wall of the tundish and enrich them to form zinc alloy slag. Finally, the alloy slag on the outer wall and the filter cloth is removed by furnace cleaning / slag removal to achieve purification of the zinc alloy melt.

[0034] 2. The electromagnetic purification process of this invention can be repeatedly carried out through the opening at the bottom of the tundish, thereby achieving multiple purifications of the zinc alloy melt and ultimately achieving efficient electromagnetic separation of various inclusions in the zinc alloy melt.

[0035] 3. The method and apparatus of the present invention can realize the continuous removal of various inclusions in die-cast zinc alloys and are suitable for the continuous industrial production of traditional die-cast zinc alloys. Attached Figure Description

[0036] Figure 1 This is a front view of the device structure for the overall process of electromagnetic purification of inclusions in the die-cast zinc alloy industrial production according to Embodiment 1 of the present invention.

[0037] Figure 2 This is a top view of the electromagnetic purification device for inclusions in the die-cast zinc alloy industrial production process according to Embodiment 1 of the present invention.

[0038] Figure 3 This is a comparison chart of the effect of different electromagnetic stirring currents on the number density of inclusions in die-cast zinc alloy in Embodiment 1 of the present invention.

[0039] Figure 4 This is a comparison chart of the effect of different electromagnetic stirring frequencies on the number density of inclusions in die-cast zinc alloy in Embodiment 1 of the present invention.

[0040] Figure 5 This is a comparison chart of the effect of different electromagnetic stirring times on the number and density of inclusions in die-cast zinc alloy in Embodiment 1 of the present invention. Detailed Implementation

[0041] The preferred embodiments of the present invention are described in detail below:

[0042] Example 1:

[0043] In this embodiment, see Figure 1 and Figure 2 An electromagnetic purification device for inclusions in the die-cast zinc alloy industrial production process is an integrated production equipment consisting of a smelting device, a purification device, and a casting device; it is a device for continuous electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process.

[0044] The smelting apparatus adopts a reverberatory furnace 1, which is equipped with a reverberatory furnace opening 2, a resistance band 4, a type K thermocouple 6, and a bottom pouring channel 7.

[0045] The purification process employs an intermediate ladle 8, which is further equipped with a resistance band 4, a type K thermocouple 6, an electromagnetic stirring coil 9, and a filter cloth 11. The intermediate ladle 8 is positioned between the bottom pouring channel 7 of the reverberatory furnace of the smelting apparatus and the casting apparatus, thereby setting up the purification process before the melt is cast into ingots. During the smelting process, the die-cast zinc alloy melt 5 obtained from the smelting reacts with oxygen to form inclusions 10. The purification process is carried out using the purification process to remove the inclusions 10 from the alloy melt.

[0046] The casting device includes iron molds 13 and a conveyor belt 15; a series of iron molds 13 are arranged sequentially on the conveyor belt 15 for conveying.

[0047] During the electromagnetic purification of inclusions in the industrial production of die-cast zinc alloy, the electrolytic zinc plate 3 is added to the reverberatory furnace 1 through the furnace opening 2. Direct current is passed through the resistance band 4, and the electrolytic zinc plate 3 is melted into zinc melt through radiation heat transfer. Then, the intermediate alloy ingot is added to the reverberatory furnace 1 through the furnace opening 2 to achieve its alloying. The resulting die-cast zinc alloy melt 5 with the required composition is melted and kept at a constant temperature. The temperature is controlled by a type K thermocouple 6 during this heating process.

[0048] Direct current is passed through a resistance band 4 above the tundish 8 to heat the tundish 8. This heating process is also temperature-controlled by a type K thermocouple 6. Then, the die-cast zinc alloy melt 5 is poured into the tundish 8 through the bottom pouring channel 7 of the reverberatory furnace. Alternating current is passed through an electromagnetic stirring coil 9 located on the outside or bottom of the tundish 8. The electromagnetic force generated by the electromagnetic stirring coil 9 drives the die-cast zinc alloy melt 5 to flow. The tundish 8 forms different connected areas through partitions. The filter cloth 11 located in the lower part of the partition of the adjacent areas of the tundish 8 is used to achieve continuous stirring. Centrifugal force drives the inclusions 10 to the side wall of the tundish 8 and enriches them to form zinc alloy slag. Finally, the zinc alloy slag on the outer wall of the tundish 8 and on the filter cloth 11 is removed by furnace cleaning / slag removal, thereby purifying the alloy melt. During the electromagnetic purification process, the die-cast zinc alloy melt 5 in the tundish 8 is repeatedly purified through the opening of the filter cloth 11 at the bottom of the tundish 8.

[0049] The purified zinc alloy melt 12 is poured into the iron mold 13 for solidification, thereby cooling and forming the die-cast zinc alloy into zinc alloy ingot 14; the conveyor belt 15 is turned on to realize the continuous implementation of the die-cast zinc alloy melting and casting process.

[0050] In this embodiment, the intermediate tundish 8 includes two intermediate tundishes connected in sequence, a first intermediate tundish and a second intermediate tundish. The two intermediate tundishes are connected by a flow channel with an opening provided by a filter cloth 11. The die-cast zinc alloy melt 5 is poured into the first intermediate tundish through the bottom pouring channel 7 of the reverberatory furnace; then it enters the second intermediate tundish through the opening of the filter cloth 11. The zinc alloy melt 12 after being processed in the second intermediate tundish is poured into the iron mold 13 through the rear pouring channel.

[0051] See Figure 1 , Figure 2 A method for electromagnetic purification of inclusions in the industrial production of die-cast zinc alloys, comprising the following steps:

[0052] Step 1, Equipment Preparation:

[0053] Electrolytic zinc plate 3 is placed into reverberatory furnace 1 through reverberatory furnace opening 2, and direct current is passed through the resistance band 4 at the top of the reverberatory furnace. The electrolytic zinc plate 3 is melted into zinc melt through radiant heat transfer and held at a constant temperature. This heating process is controlled by a type K thermocouple 6. Subsequently, intermediate alloy ingots are added into reverberatory furnace 1 through reverberatory furnace opening 2 to achieve alloying, and are melted and prepared into die-cast zinc alloy melt 5 with the required composition, ready for casting.

[0054] Step 2, Electromagnetic purification process:

[0055] Direct current is passed through the resistance band 4 to heat the tundish 8. This heating process is also controlled by the K-type thermocouple 6. Then, the die-cast zinc alloy melt 5 is poured into the tundish 8 through the bottom pouring channel 7 of the reverberatory furnace. Alternating current is passed through the electromagnetic stirring coil 9 at the bottom of the tundish. The electromagnetic force generated by the electromagnetic stirring coil 9 drives the zinc alloy melt through the opening of the filter cloth 11 in the lower part of the tundish to achieve continuous stirring. Centrifugal force drives the inclusions 10 to the side wall of the tundish 8 to accumulate and form zinc alloy slag. Finally, the alloy slag on the outer wall and the filter cloth 11 is removed by furnace cleaning / slag removal to purify the melt. This electromagnetic purification process can be repeated through the intermediate opening to achieve multiple purification of the zinc alloy melt.

[0056] Step 3, Continuous Process:

[0057] The purified zinc alloy melt 12 is poured into the iron mold 13 to achieve the cooling and forming of the die-cast zinc alloy into zinc alloy ingot 14. The conveyor belt 15 is then turned on to realize the continuous preparation of this process.

[0058] This embodiment of the method and apparatus involves adding an tundish before casting the die-cast zinc alloy ingot, and placing an electromagnetic stirring coil at the bottom of the tundish, through which an alternating current is applied. The generated electromagnetic force drives the flow of the die-cast zinc alloy molten material, which is continuously stirred through an opening in the lower part of the tundish equipped with a filter cloth. Centrifugal force drives various inclusions with a large density difference from the zinc molten material to the outer wall of the tundish, where they accumulate and form zinc alloy slag. Finally, the alloy slag on the outer wall and the filter cloth is removed by furnace cleaning / slag removal, thus purifying the melt and achieving the separation of various inclusions in the zinc alloy. This embodiment of the method and apparatus can achieve continuous removal of various inclusions in die-cast zinc alloys and is suitable for continuous industrial production of traditional die-cast zinc alloys.

[0059] This embodiment describes a method and apparatus for electromagnetic purification of inclusions in the industrial production of die-cast zinc alloys. Before casting the zinc alloy ingot, an tundish is added, and an electromagnetic stirring coil is placed at the bottom of the tundish. An alternating current is applied to the electromagnetic stirring coil. The electromagnetic force generated by the stirring coil drives the flow of the die-cast zinc alloy melt. The melt is continuously stirred through an opening with a filter cloth at the bottom of the tundish. Centrifugal force drives inclusions with a large density difference from the zinc melt to the outer wall of the tundish, where they accumulate and form zinc alloy slag. The slag on the outer wall and the filter cloth is then removed by furnace cleaning / slag removal. This electromagnetic purification process of the die-cast zinc alloy melt can be repeated through the opening at the bottom of the tundish, achieving multiple purifications of the zinc alloy melt and ultimately realizing efficient electromagnetic separation of various inclusions within the zinc alloy melt. The device in this embodiment is simple and easy to operate. It is not only suitable for the continuous industrial production of traditional die-cast zinc alloys, but also for the purification of inclusions in hot-dip galvanized alloys, aluminum and its alloys, magnesium and its alloys, tin and its alloys, copper and its alloys, gallium and its alloys, indium and its alloys, antimony and its alloys, bismuth and its alloys, semiconductor melts and other non-ferrous alloys. It is also suitable for the purification of melts such as special steel and high-quality steel, and for the concentration and enrichment of valence phases in lava and slag.

[0060] Example 2:

[0061] This embodiment is basically the same as Embodiment 1, except that the electromagnetic purification process in step 2 has been changed:

[0062] The die-cast zinc alloy molten material 5 is poured into the tundish 8 for electromagnetic purification. Direct current is passed through the resistance band 4, heating the molten zinc alloy in the tundish 8 via thermal radiation. Temperature is controlled by a type K thermocouple 6 to prevent solidification. A 30A, 25Hz alternating current is passed through the electromagnetic stirring coil 9, and stirring is maintained for 20 minutes. The electromagnetic force generated by the electromagnetic stirring coil 9 drives the zinc alloy molten material through an opening in the lower part of the tundish equipped with filter cloth 11, achieving continuous stirring. Centrifugal force drives inclusions 10 in the zinc alloy to the side wall of the tundish 8, where they accumulate and form zinc alloy slag. Finally, the alloy slag on the outer wall and filter cloth 11 is removed by furnace cleaning / slag removal, thus purifying the die-cast zinc alloy molten material. See also... Figure 3 The effects of stirring currents of 30A, 40A, and 50A on the inclusion density in die-cast zinc alloy ingots after stirring for 20 minutes at a frequency of 25Hz were compared. Electromagnetic stirring significantly reduced the number of inclusions in the die-cast zinc alloy ingots, and at the given stirring time and frequency, lower stirring currents were better. See also... Figure 4 The effects of stirring frequencies of 10Hz, 25Hz, and 50Hz on the inclusion density in die-cast zinc alloy ingots after stirring for 20 minutes at a current of 30A were compared. It can be seen that, under the current stirring time of 20 minutes and current of 30A, a stirring frequency of 25Hz is the optimal stirring frequency. (See also...) Figure 5 This study compared the effects of stirring times of 5 minutes, 10 minutes, and 20 minutes on the inclusion density in die-cast zinc alloy ingots under the same stirring current of 30A and stirring frequency of 25Hz. It can be seen that under the current conditions of 30A stirring current and 25Hz stirring frequency, stirring for 5 minutes is the optimal stirring time. In conclusion, applying electromagnetic stirring can effectively reduce the inclusion density of various types of inclusions in die-cast zinc alloy ingots. The optimal electromagnetic stirring parameters are a stirring current of 30A, a frequency of 25Hz, and a stirring time of 5 minutes.

[0063] In summary, the method and apparatus for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process described in the above embodiments involve adding an tundish before casting the zinc alloy ingot, and adding an electromagnetic stirring coil at the bottom of the tundish, with an alternating current flowing through the electromagnetic stirring coil. The electromagnetic force generated by the electromagnetic stirring coil drives the flow of the die-cast zinc alloy melt, achieving continuous stirring through an opening with a filter cloth at the bottom of the tundish. Centrifugal force drives inclusions with a large density difference from the zinc melt to the outer wall of the tundish, where they accumulate and form zinc alloy slag. Finally, the alloy slag on the outer wall and the filter cloth is removed by furnace cleaning / slag removal. This electromagnetic purification process of the die-cast zinc alloy melt can be repeated through the opening at the bottom of the tundish, thus achieving multiple purifications of the zinc alloy melt.

[0064] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to electromagnetic purification in die-cast zinc alloys, but is also suitable for hot-dip galvanized alloys, aluminum and its alloys, magnesium and its alloys, tin and its alloys, copper and its alloys, gallium and its alloys, indium and its alloys, antimony and its alloys, bismuth and its alloys, semiconductor melts, and other non-ferrous alloys. It is also suitable for the purification of melts of special steels and high-quality steels, and for the concentration and enrichment of valence phases in lava and slag. Any changes, modifications, substitutions, combinations, or simplifications made based on the spirit and principle of the technical solution of the present invention shall be considered equivalent substitutions. As long as they conform to the inventive purpose of the present invention and do not depart from the technical principle and inventive concept of the method and apparatus for removing inclusions inside molten metal using electromagnetic purification technology, they shall all fall within the protection scope of the present invention.

Claims

1. A device for electromagnetic purification of inclusions in the industrial production process of die-cast zinc alloy, characterized in that: An integrated production equipment consisting of smelting equipment, purification equipment and casting equipment; The smelting apparatus adopts a reverberatory furnace (1), which is equipped with a reverberatory furnace opening (2), a resistance band (4), a type K thermocouple (6), and a bottom pouring channel (7). The purification process uses an intermediate ladle (8), which is equipped with a resistance band (4), a type K thermocouple (6), an electromagnetic stirring coil (9), and a filter cloth (11). The intermediate ladle (8) is set between the bottom pouring channel (7) of the reverberatory furnace of the smelting device and the casting device, so that the purification process is set before the melt is cast into ingots. During the smelting process, the die-cast zinc alloy melt (5) obtained by smelting reacts with oxygen to form inclusions (10). The purification process is carried out by the purification process to remove the inclusions (10) in the alloy melt. The casting device includes iron molds (13) and a conveyor belt (15); a series of iron molds (13) are arranged in sequence on the conveyor belt (15) for conveying; When performing electromagnetic purification of inclusions in the industrial production of die-cast zinc alloy, the electrolytic zinc plate (3) is added to the reverberatory furnace (1) through the furnace opening (2), and DC current is passed through the resistance band (4). The electrolytic zinc plate (3) is melted into zinc melt through radiation heat transfer. Then, the intermediate alloy ingot is added to the reverberatory furnace (1) through the furnace opening (2) to achieve its alloying. The alloy is melted into the die-cast zinc alloy melt (5) with the required composition and kept at a constant temperature. The temperature is controlled by a type K thermocouple (6) during this heating process. Direct current is passed through the resistance band (4) set above the tundish (8) to heat the tundish (8). This heating process is also controlled by a type K thermocouple (6). Then, the die-cast zinc alloy melt (5) is poured into the tundish (8) through the bottom pouring channel (7) of the reverberatory furnace. Alternating current is passed through the electromagnetic stirring coil (9) set on the outside or bottom of the tundish (8). The electromagnetic force generated by the electromagnetic stirring coil (9) is used to drive the die-cast zinc alloy melt (5) to flow. The tundish (8) forms different connected areas through the partition. The filter cloth (11) set in the lower part of the partition of the adjacent area of ​​the tundish (8) is used to achieve continuous stirring. The centrifugal force is used to drive the inclusions (10) to the side wall of the tundish (8) to accumulate and form zinc alloy slag. Finally, the zinc alloy slag on the outer wall of the tundish (8) and the filter cloth (11) is removed by furnace cleaning / slag removal, thereby purifying the alloy melt. The final purified zinc alloy melt (12) is poured into the iron mold (13) for solidification, thereby achieving the cooling and forming of the die-cast zinc alloy into zinc alloy ingots (14); the conveyor belt (15) is turned on to realize the continuous implementation of the die-cast zinc alloy melting and casting process. During the electromagnetic purification process, the die-cast zinc alloy melt (5) in the tundish (8) is repeatedly purified through the opening of the filter cloth (11) at the bottom of the tundish (8). The intermediate ladle (8) includes at least two intermediate ladles connected in sequence. The intermediate ladles are connected by a flow channel with an opening provided by a filter cloth (11). The die-cast zinc alloy melt (5) is poured into the first intermediate ladle through the bottom pouring channel (7) of the reverberatory furnace. Then it enters the next intermediate ladle through the opening of the filter cloth (11). The zinc alloy melt (12) after being processed in the last intermediate ladle is poured into the iron mold (13) through the rear pouring channel. When the zinc alloy melt is poured into the tundish (8) for electromagnetic purification, the tundish (8) is divided into at least two parts. The openings of the lower part are interconnected, and the k-type thermocouple (6) is inserted into the upper part. Direct current is passed through the resistance band (4) on the upper side of the tundish (8) to achieve heat preservation of the zinc alloy melt through radiation heat transfer. The heat preservation process is controlled by the k-type thermocouple (6). Alternating current is passed through the electromagnetic stirring coil (9) on the lower side of the tundish (8) to drive the zinc alloy melt to flow using electromagnetic force. The tundish (8) is continuously stirred through the openings of the lower part. A filter cloth (11) is set at the opening to filter the melt and collect oxide slag. Centrifugal force is used to drive the inclusions to the outer wall of the tundish (8) to accumulate and form zinc alloy slag. Finally, the alloy slag on the furnace wall and the filter cloth (11) is removed by furnace cleaning / slag removal. This process can be repeated through the interconnected openings to achieve multiple purification of the die-cast zinc alloy melt.

2. The device for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process according to claim 1, characterized in that: The intermediate tundish (8) includes two intermediate tundishes connected in sequence, the first intermediate tundish and the second intermediate tundish. The two intermediate tundishes are connected by a flow channel with an opening provided by a filter cloth (11). The die-cast zinc alloy melt (5) is poured into the first intermediate tundish through the bottom pouring channel (7) of the reverberatory furnace. Then it enters the second intermediate tundish through the opening of the filter cloth (11). The zinc alloy melt (12) after being processed in the second intermediate tundish is poured into the iron mold (13) through the rear pouring channel.

3. The device for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process according to claim 1, characterized in that: The resistance band (4) used as the heating source of the reverberatory furnace can be set on the side or bottom of the reverberatory furnace (1) to provide resistance heating; the resistance heating method can also be replaced by natural gas heating or induction heating through induction heating coil.

4. A method for electromagnetic purification of inclusions in the industrial production of die-cast zinc alloys, utilizing the electromagnetic purification device for inclusions in the industrial production of die-cast zinc alloys as described in claim 1, characterized in that... Includes the following steps: Step 1, Raw material and equipment preparation: Electrolytic zinc plate (3) is placed into reverberatory furnace (1) through reverberatory furnace opening (2), and DC current is passed through the resistance band (4) at the top of the reverberatory furnace. Electrolytic zinc plate (3) is melted into zinc melt by radiation heat transfer and kept at a constant temperature. This heating process is controlled by K-type thermocouple (6). Then, intermediate alloy ingot is added into reverberatory furnace (1) through reverberatory furnace opening (2) to achieve alloying, melt and mix into die-cast zinc alloy melt (5) with the required composition and wait for casting. Step 2, Electromagnetic purification process: Direct current is passed through the resistance band (4) set on the tundish (8) to heat the tundish (8). This heating process is also controlled by the K-type thermocouple (6). Then, the die-cast zinc alloy melt (5) is poured into the tundish (8) through the bottom pouring channel (7) of the reverberatory furnace. Alternating current is passed through the electromagnetic stirring coil (9) at the bottom of the tundish. The electromagnetic force generated by the electromagnetic stirring coil (9) drives the zinc alloy melt through the opening of the filter cloth (11) in the lower part of the tundish to achieve continuous stirring. The centrifugal force drives the inclusions (10) to the side wall of the tundish (8) to accumulate and form zinc alloy slag. Finally, the alloy slag on the outer wall and the filter cloth (11) is removed by furnace cleaning / slag removal to purify the melt. The electromagnetic purification process can be repeated through the opening of the filter cloth (11) at the bottom of the tundish (8) to achieve multiple purification of the zinc alloy melt. Step 3, Continuous casting process: The final purified zinc alloy melt (12) is poured into the iron mold (13) to achieve the cooling and forming of the die-cast zinc alloy into a zinc alloy ingot (14). The conveyor belt (15) is turned on to realize the continuous operation of the die-cast zinc alloy melting and casting process.

5. The method for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process according to claim 4, characterized in that: The degree of inclusion removal can be controlled by changing the current intensity, current frequency and stirring time of the alternating current passed into the electromagnetic stirring coil (9). The electromagnetic parameters are stirring current 0-50A, stirring frequency 1-100Hz and stirring time 0.01-0.5 hours.

6. The method for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process according to claim 4, characterized in that: The direct current passed through the resistance band (4), which serves as an electric heating device, has a current intensity of no more than 50,000 A.

7. The method for electromagnetic purification of inclusions in the die-cast zinc alloy industrial production process according to claim 4, characterized in that: It is applicable to the production of any type of die-cast zinc alloy ingot, including round billets, square billets, slab billets, tube billets and special-shaped billets; it is applicable to different grades of die-cast zinc alloy materials, including at least one of Zamak 2, Zamak 3, Zamak 4, Zamak 5, Zamak 7, ZA-8, ZA-12, and ZA-27.

8. The method for electromagnetic purification of inclusions in the industrial production process of die-cast zinc alloy according to claim 4, characterized in that: Electromagnetic purification is not limited to die-cast zinc alloys, but is also suitable for hot-dip galvanized alloys, aluminum and its alloys, magnesium and its alloys, tin and its alloys, copper and its alloys, gallium and its alloys, indium and its alloys, antimony and its alloys, bismuth and its alloys, semiconductor melts and other non-ferrous alloys, as well as the purification of special steels and high-quality steels. It is also suitable for the concentration and enrichment of valence phases in lava and slag.

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