A device and method for rapidly preparing high-density MgB2 wire

Abstract

The present invention discloses an apparatus and method for rapidly preparing high-density MgB2 wire, comprising a precursor powder mixing device and a precursor powder tube loading device. The precursor powder mixing device can provide a voltage of 220V, and can grind the weighed precursor powder wire in large quantities in a glove box, so as to obtain a large amount of precursor powder in a short time, avoiding the large amount of time consumed by grinding, thereby reducing production time costs, reducing labor expenses, and improving production efficiency. The precursor powder tube loading device for machine-extruded precursor powder tube loading can provide a voltage of 220V for machine tube loading in a glove box, thereby solving the problems of low density caused by manual tube loading, low production rate and low performance caused by time and cost, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting wire preparation, and in particular to a device and method for rapidly preparing high-density MgB2 wire. Background Art

[0002] Since its discovery in 2001, magnesium diboride (MgB2) has been studied as a next-generation practical superconducting material for over 20 years and has made significant progress. Its critical transition temperature (Tc) of 39K is close to the McMillan limit of 40K predicted by BCS theory, making it a classic BCS superconductor. MgB2 has a coherence length of 6-7 nanometers and a simple hexagonal crystal structure. The distance between boron atoms within a boron layer is smaller than that between adjacent boron atoms, resulting in anisotropy. Unlike high-temperature oxide superconductors, MgB2 lacks weak links at its grain boundaries. Compared to low-temperature superconductors (NbTi and Nb3Sn), MgB2 boasts abundant raw material resources and low manufacturing costs. Furthermore, MgB2 is expected to be usable at temperatures around 20K. It has entered the practical research stage, with several companies, including Columbus in Italy and Hyper Tec in the United States, already engaged in commercial production. The resulting MgB2 wire and ribbon have been successfully applied in magnetic resonance imaging (MRI), superconducting cables, and superconducting motors.

[0003] Practical MgB2 multi-core superconducting wires are usually prepared using the in-situ powder loading method (in-situ PIT), which involves loading Mg powder and B powder into a metal tube and processing it into a single-core rod through methods such as spinning, drawing and rolling.

[0004] The traditional in-situ powder-in-tube (PIT) method for preparing MgB2 precursor powder often involves grinding Mg and B powders in a mortar and pestle in a glove box at an atomic ratio of 1:2. Typically, 1 hour of grinding yields 5g of the mixed Mg and B precursor powder. However, when preparing kilometer-scale multi-core wires, 200g to 400g of mixed precursor powder is often required, significantly extending the grinding time to 40-80 hours, significantly prolonging a single experiment. Furthermore, manual extrusion is often used during the tube-forming process, resulting in less than ideal density for the prepared MgB2, leading to low overall wire performance. Summary of the Invention

[0005] The purpose of the present invention is to provide an apparatus and method for rapidly preparing high-density MgB2 wire, so as to overcome the combined problems in the prior art of long time and small amount of grinding MgB2 precursor powder and low density in the traditional manual tube filling process, resulting in long wire preparation time / low performance.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A device for rapidly preparing high-density MgB2 wire, comprising a precursor powder mixing device and a precursor powder tube loading device;

[0008] The precursor powder mixing device includes a barrel body, a barrel cover, a frame, a stirring blade, a motor, a reducer and an electric control box. The barrel body is welded and fixed above the frame, and the barrel cover can be opened and connected to the open end of the top of the barrel body; spoiler ribs are welded on the inner wall of the barrel body, and a motor is fixed to the bottom end of the barrel body. The output end of the motor is connected to the input end of the reducer, and the output shaft of the reducer is fixedly connected to the stirring blade arranged inside the barrel body. A discharge port is provided on the front side of the bottom end of the barrel body, and a discharge pump is provided on the discharge port. An electric control box is fixed to the middle right side of the barrel body, and the motor is electrically connected to the electric control box.

[0009] The precursor powder pipe loading device includes a telescopic drive, a magnetic connector, a fixed pipe, a feeding port, a telescopic pressure arm, a squeezing disc, a magnetic widening pipe, a base, a pressure sensor and a signal transmission line;

[0010] The magnetic widening pipe is arranged on the top of the base, and the fixed pipe is fixed to the top of the magnetic widening pipe by using magnetic screws. A control switch for controlling its operation is connected to the bottom of the telescopic drive, and the bottom of the telescopic drive is connected to the magnetic connector. The magnetic connector and the fixed pipe are fixed by using magnetic screws. The upper end of the telescopic pressure arm is fixedly connected to the output shaft of the telescopic drive, and the lower end of the telescopic pressure arm is fixedly connected to the extrusion disc with screws. The extrusion disc is located inside the magnetic widening pipe, and the telescopic drive drives the extrusion disc to perform lifting movements inside the magnetic widening pipe through the telescopic pressure arm; the feeding port is placed on the fixed pipe and connected to the inside of the magnetic widening pipe, and the corresponding feeding ports on the extrusion disc are respectively provided with feeding holes; the pressure sensor is placed on the base, and the pressure sensor and the signal transmission line are electrically connected to sense the degree of extrusion of the telescopic pressure arm.

[0011] The upper part of the barrel body is in the shape of a hollow cylinder, and the lower part is in the shape of a hollow cone.

[0012] The bottom end of the frame is connected with a caster.

[0013] The barrel cover is flippably connected to the open end of the top of the barrel body through a hinge, and a plurality of lock buckles are provided at positions corresponding to the barrel cover and the barrel body.

[0014] A handle is welded on the left side of the top end of the barrel cover.

[0015] An alloy upper cover is welded and fixed on the telescopic driver.

[0016] The method for preparing a high-density MgB2 superconducting wire using the above-mentioned equipment comprises the following steps:

[0017] Step 1: Mg and B powders are mixed in an atomic ratio of 1:2, and ground and mixed in a glove box using a precursor powder mixing device to obtain a precursor powder; the ground precursor powder is packed into a high-density tube using a precursor powder tube loading device, and then assembled into a Cu / Nb / MgB2 single core rod in a Cu / Nb tube, which is processed to a certain size by swaging and drawing; a Nb rod is placed in a Cu tube to be assembled into a Cu / Nb center rod, which is processed to a certain size by swaging or drawing;

[0018] Step 2: The Cu / Nb / MgB2 single core rods and Cu / Nb center rods of the same size are cut to length and cut in sequence, and then placed in a Monel tube to assemble into an "n+m" core composite sheath, where n is the number of Cu / Nb / MgB2 single core rods and m is the number of Cu / Nb center rods;

[0019] Step 3: The composite sheath is subjected to spinning and drawing processing. During the processing, different processing wire diameters are selected, and then the spinning and drawing processes are continued until the wire is processed to the final finished wire size: Φ0.83mm~Φ1.4mm;

[0020] Step 4: Perform final heat treatment on the finished wire to obtain MgB2 multi-core superconducting wire.

[0021] The specific implementation method of using the precursor powder mixing device to mix the precursor powder in step 1 is as follows: open the barrel cover in the precursor powder mixing device, use an electronic balance to weigh Mg and B powders with an atomic ratio of 1:2, pour them into the precursor powder mixing device, start the motor, and rotate the stirring blade at high speed for a predetermined time to obtain a mixed precursor powder.

[0022] The specific implementation method of using the precursor powder tube loading device to load the tube in step 1 is as follows: select a Nb tube of appropriate size for loading, adjust the magnetic widening pipe to an appropriate size according to the selected Nb tube size, place the Nb tube into the magnetic widening pipe, and then select an extrusion disc of appropriate diameter; after completing the above steps, add the precursor powder obtained from the precursor powder mixing device from the feed port, start the precursor powder tube loading device, and after one extrusion is completed, retract the pressure arm back to the initial position, add precursor powder again, and repeat the above steps to obtain a high-density Nb / MgB2 single-core rod.

[0023] In the implementation step 1 mentioned above, a control experiment was designed to weigh the same mass of Mg and B powders and mix them according to the atomic ratio of 1:2. One group was not ground and piped using the above equipment, and the other group was ground and piped using the above equipment.

[0024] In step 2 above, four wires were drawn and subsequently analyzed for performance. One wire was 18+1 MgB2, obtained using the apparatus described above. The other wire was 18+1 MgB2, obtained without the apparatus. A second control wire was 30+6 MgB2, obtained using the apparatus described above. The other wire was 30+6 MgB2, obtained without the apparatus.

[0025] The specific method of performing the final heat treatment on the finished wire in step 4 is: heating the wire to 560°C~670°C in an inert gas environment for 30min~60min and keeping the temperature for 1h~4h.

[0026] The principle behind this invention is that the MgB2 preparation process requires long grinding times, and processing a batch of wire can often require extensive manual grinding. Furthermore, manual tubing results in less-than-ideal wire density. This significantly increases the number of voids after annealing, reducing the wire's ultimate performance. Furthermore, low-density wires are prone to hardening during processing, leading to uneven deformation of multi-core wires and the occurrence of voids, which in turn degrades wire performance.

[0027] The beneficial effect of the present invention is that, when comparing 18+1 core wires using the above-mentioned equipment with those not using the above-mentioned equipment, the overall precursor powder processing time is reduced by 22 hours, the final wire density is increased by 18%, and Jc is 1.4 times that of the unused device, reaching 1.44×105A / cm2 in a 5K environment. 2 @5k. When comparing 30+6 core wires with and without the above-mentioned device, the overall precursor powder processing time was reduced by 32 hours, the final wire density increased by 21%, and Jc was 1.7 times that of the wire without the device, reaching 2.36×105A / cm at 5K. 2 @5k.

[0028] The present invention provides a precursor powder mixing device for rapidly grinding MgB2 precursor powder wires and a precursor powder loading device for machine-extruded tube-filled precursor powders. The precursor powder mixing device can provide a voltage of 220V and perform large-scale grinding of weighed precursor powder wires in a glove box, thereby obtaining large quantities of precursor powders in a short period of time and avoiding the large amount of time consumed by grinding powders. This can reduce production time costs, reduce labor expenditures, and improve production efficiency. The precursor powder loading device for machine-extruded tube-filled precursor powders can provide a voltage of 220V for machine tube filling in a glove box, thereby solving the problems of low density, time-consuming costs, and low performance caused by manual tube filling. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments;

[0030] Figure 1 It is a schematic diagram of the precursor powder mixing device;

[0031] Figure 2 Schematic diagram of the precursor powder loading device. DETAILED DESCRIPTION

[0032] like Figure 1-2 As shown, the present invention provides a device for rapidly preparing high-density MgB2 wire, including a precursor powder mixing device and a precursor powder tube loading device;

[0033] The precursor powder mixing device includes a barrel 1, a barrel cover 11, a frame 5, a stirring blade 14, a motor 7, a reducer 8 and an electric control box 9. The barrel 1 is welded and fixed on the top of the frame 5, and the bottom end of the frame 5 is connected to a caster 6. The upper part of the barrel 1 is a hollow cylinder, and the lower part is a hollow cone. The barrel cover 11 can be opened and connected to the open end at the top of the barrel body 1. Specifically, the barrel cover 11 can be flipped and connected to the open end at the top of the barrel body 1 through a hinge 10. A plurality of locks 13 are provided at the positions corresponding to the barrel cover 11 and the barrel body 1. A handle 12 is welded to the left side of the top of the barrel cover 11. Turbulator ribs 15 are welded to the inner wall of the barrel 1. A motor 7 is fixed to the bottom end of the barrel 1. The output end of the motor 7 is connected to the input end of the reducer 8. The output shaft of the reducer 8 is fixedly connected to the stirring blade 14 placed inside the barrel 1. A discharge port 4 is provided on the front side of the bottom end of the barrel 1. The discharge port 4 is provided with a discharge plate 2, which is fixed by a locking bolt 3. An electric control box 9 is fixed to the middle of the right side of the barrel 1. The motor 7 is electrically connected to the electric control box 9.

[0034] The precursor powder loading device includes a telescopic driver 02, a magnetic connector 04, a fixed pipe 05, a feeding port 06, a telescopic pressure arm 07, an extrusion disc 08, a magnetic widening pipe 09, a base 010, a pressure sensor 011 and a signal transmission line 012;

[0035] The magnetic widening pipe 09 is located on top of the base 010, and the fixed pipe 05 is fixed to the top of the magnetic widening pipe 09 with magnetic screws, which facilitates the replacement of pipes of different diameters and increases the number of usage scenarios. A control switch 03 for controlling its operation is connected below the telescopic actuator 02. The telescopic actuator 02 can be a hydraulic cylinder, etc. The bottom of the telescopic actuator 02 is connected to the magnetic connector 04. The magnetic connector 04 and the fixed pipe 05 are connected and fixed with magnetic screws, which facilitates the replacement of the fixed pipe 05 and the magnetic widening pipe 09, as well as the specifications of the telescopic pressure arm 07. The upper end of the telescopic pressure arm 07 is fixedly connected to the output shaft of the telescopic actuator 02, and the lower end of the telescopic pressure arm 07 is screwed to fix the extrusion disc. The extrusion disc is located inside the magnetic widening pipe 09, and the diameter of the extrusion disc can be adjusted according to the thickness of the pipe being installed. The telescopic actuator 02 drives the extrusion disc to move up and down inside the magnetic widening pipe 09 through the telescopic pressure arm 07. The feeding port 06 is placed on the fixed pipe 05 and connected to the inside of the magnetic widening pipe 09. The extrusion disc is provided with feeding holes corresponding to the feeding port 06; the pressure sensor is placed on the base 010, and the pressure sensor 011 and the signal transmission line 012 are electrically connected to sense the extrusion degree of the telescopic pressure arm 07. When the pressure value is greater than 500N, the precursor powder loading device automatically stops, the telescopic pressure arm 07 returns to the initial position, and powder is added from the feeding port for the next extrusion.

[0036] The base 010 is an alloy base 010, which can prevent the telescopic pressure arm 07 from being damaged due to excessive force by increasing the base hardness.

[0037] An alloy upper cover 01 is welded and fixed on the telescopic driver 02. The alloy upper cover 01 is used to protect the telescopic driver 02 and increase the service life of the telescopic driver 02.

[0038] The method for preparing a high-density MgB2 superconducting wire using the above-mentioned equipment comprises the following steps:

[0039] Step 1: Mg and B powders are mixed in an atomic ratio of 1:2, and ground and mixed in a glove box using a precursor powder mixing device to obtain a precursor powder; the ground precursor powder is packed into a high-density tube using a precursor powder tube loading device, and then assembled into a Cu / Nb / MgB2 single core rod in a Cu / Nb tube, which is processed to a certain size by swaging and drawing; a Nb rod is placed in a Cu tube to be assembled into a Cu / Nb center rod, which is processed to a certain size by swaging or drawing;

[0040] Step 2: The Cu / Nb / MgB2 single core rods and Cu / Nb center rods of the same size are cut to length and cut in sequence, and then placed in a Monel tube to assemble into an "n+m" core composite sheath, where n is the number of Cu / Nb / MgB2 single core rods and m is the number of Cu / Nb center rods;

[0041] Step 3: The composite sheath is subjected to spinning and drawing processing. During the processing, different processing wire diameters are selected, and then the spinning and drawing processes are continued until the wire is processed to the final finished wire size: Φ0.83mm~Φ1.4mm;

[0042] Step 4: The finished wire is subjected to a final heat treatment, specifically, the wire is heated to 560°C to 670°C in an inert gas environment for 30 to 60 minutes and then kept at this temperature for 1 to 4 hours to obtain a MgB2 multi-core superconducting wire.

[0043] The specific implementation method for mixing the precursor powder using the precursor powder mixing device in step 1 is as follows: the barrel lid 11 of the precursor powder mixing device is opened, Mg and B powders with an atomic ratio of 1:2 are weighed using an electronic balance, and then poured into the precursor powder mixing device. The motor is started, and the stirring blades 14 rotate at high speed for a predetermined time to obtain mixed precursor powder. The spoiler ribs prevent the powder from adhering to the inner side of the barrel 1, resulting in less powder being weighed than actually obtained.

[0044] The specific implementation method of using the precursor powder pipe loading device to load the pipe in step 1 is as follows: select a Nb tube of appropriate size for loading, adjust the magnetic widening pipe 09 to an appropriate size according to the selected Nb tube size, place the Nb tube into the magnetic widening pipe 09, and then select an extrusion disc of appropriate diameter; after the above steps are completed, use the precursor powder obtained from the precursor powder mixing device to add it from the feed port, start the precursor powder pipe loading device, and after one extrusion is completed, retract the pressure arm 07 back to the initial position, add precursor powder again, and repeat the above steps to obtain a high-density Nb / MgB2 single-core rod.

[0045] Example 1

[0046] Step 1: Weigh 34.45 g of Mg powder and 30.55 g of B powder in a glove box, grind and mix them using a precursor powder mixing device to obtain precursor powder, and use a precursor powder tube loading device to load the precursor powder into a Cu / Nb tube in multiple times using the telescopic pressure arm 07 and the feedback of the pressure sensor to assemble into a Cu / Nb / MgB2 single core rod, and pull the single core rod to Φ2.44 mm by spinning and drawing; load the Nb rod into the Cu tube to form a Cu / Nb center rod, and pull the center rod to Φ2.44 mm by spinning and drawing.

[0047] Step 2: After drawing the Cu / Nb / MgB2 single-core rods and Cu / Nb center rods prepared in step 1 to Φ2.44 mm, cut them into 75 cm long wires, including 18 Cu / Nb / MgB2 single-core rods and 1 Cu / Nb center rod. These wires are then placed in a Monel sheath with the center rod in the middle and the surrounding Cu / Nb / MgB2 single-core rods closely packed, to form an 18+1 core composite sheath.

[0048] Step 3: Process the 75cm wire prepared in Step 2. The Monel / (Cu / Nb / MgB2) wire, initially sized at Φ14mm, is spun and broken. After being spun to Φ10.5mm, it is drawn. Roller dies are used to process the wire to Φ8.6mm, Φ7.6mm, and Φ5.9mm to eliminate stress. This allows the wire to be processed to the desired length. After using the roller die at Φ5.9mm, all remaining dies are processed using round dies until the wire is finally processed to Φ1.0mm.

[0049] Step 4: The composite wire drawn to Φ1.0mm in step 4 is placed in an argon atmosphere in a GLX1400 tube furnace. Specifically, the two wires are wrapped with Nb foil and placed in a magnetic boat. The temperature is raised from 25℃ to 630℃ at 5℃ / min in the tube furnace. After 121 minutes, the temperature is raised to 630℃ and kept at this temperature for 120 minutes before cooling. The wire is taken out after cooling to room temperature. After testing and calculation, the overall density of the wire is 57.82%, and the critical current density Jc of the wire reaches 1.44×105A / cm 2 @5k

[0050] At the same time, the wire that was drawn according to the above steps without using the precursor powder mixing device and the precursor powder tube device was calculated and tested. It can be found that the wire density without using the precursor powder mixing device and the precursor powder tube device is only 49% and 1.02×105A / cm 2 @5k, and the initial grinding and tube loading time is as long as 23 hours.

[0051] Example 2

[0052] Step 1: Weigh 53g of Mg powder and 47g of B powder in a glove box, grind and mix them using a precursor powder mixing device to obtain precursor powder, and use a precursor powder tube loading device to load the precursor powder into a Cu / Nb tube in multiple times using the telescopic pressure arm 07 and the feedback of the pressure sensor to assemble into a Cu / Nb / MgB2 single-core wire, and draw the single-core rod to Φ1.76mm by spinning and drawing; load the Nb rod into the Cu tube to form a Cu / Nb center rod, and draw the center rod to Φ1.76mm by spinning and drawing.

[0053] Step 2: After drawing the Cu / Nb / MgB2 single-core rods and Cu / Nb center rods prepared in step 1 to Φ1.76mm, cut them into 75cm long wires, including 30 Cu / Nb / MgB2 single-core wires and 7 Cu / Nb center rods. Place them in a Monel sheath with the center rod in the middle and the surrounding Cu / Nb / MgB2 single-core rods closely packed, to assemble a 30+7-core composite sheath.

[0054] Step 3: Process the 75cm wire prepared in Step 2 by spinning the Monel / (Cu / Nb / MgB2) with an initial size of Φ14mm. After the initial size is spun to Φ10.5mm, it is drawn. When drawing to Φ8.6mm, Φ8.1mm, Φ7.6mm, Φ5.9mm, Φ5.3mm, Φ4.7mm, Φ2.9mm, and other sizes, roller dies are used to eliminate the stress of the wire itself. This allows the wire to be processed to the desired length. After using the roller die at Φ2.9mm, all remaining dies are processed using round dies until the wire is finally processed to Φ1.0mm.

[0055] Step 4: The composite wire drawn to Φ1.0mm in step 4 is placed in an argon atmosphere in a GLX1400 tube furnace. Specifically, the two wires are wrapped with Nb foil and placed in a magnetic boat. The temperature is raised from 25℃ to 620℃ at 5℃ / min in the tube furnace. After 116 minutes, the temperature is raised to 620℃ and kept at this temperature for 120 minutes before cooling. The wire is taken out after cooling to room temperature. After testing and calculation, the overall density of the wire is 56.87%, and the critical current density Jc of the wire reaches 2.36×105A / cm 2 @5k.

[0056] At the same time, the wire that was drawn according to the above steps without using the precursor powder mixing device and the precursor powder tube device was calculated and tested. It can be found that the wire density without using the precursor powder mixing device and the precursor powder tube device is only 47% and 1.39×105A / cm 2 @5k. And the initial grinding and tube loading time is as long as 33 hours.

[0057] The implementation of the present invention is described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are illustrative rather than limiting the present invention. Those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered by the scope of the claims and description of the present invention.

Claims

1. A method for rapidly preparing high-density MgB2 wire, characterized in that: A device for preparing high-density MgB2 superconducting wire is used, the device comprising a precursor powder mixing device and a precursor powder tube loading device; The precursor powder mixing device includes a barrel body, a barrel cover, a frame, a stirring blade, a motor, a reducer and an electric control box. The barrel body is welded and fixed above the frame, and the barrel cover can be opened and connected to the open end of the top of the barrel body; spoiler ribs are welded on the inner wall of the barrel body, and a motor is fixed to the bottom end of the barrel body. The output end of the motor is connected to the input end of the reducer, and the output shaft of the reducer is fixedly connected to the stirring blade arranged inside the barrel body. A discharge port is provided on the front side of the bottom end of the barrel body, and a discharge pump is provided on the discharge port. An electric control box is fixed to the middle right side of the barrel body, and the motor is electrically connected to the electric control box. The precursor powder pipe loading device includes a telescopic drive, a magnetic connector, a fixed pipe, a feeding port, a telescopic pressure arm, a squeezing disc, a magnetic widening pipe, a base, a pressure sensor and a signal transmission line; The magnetic widening pipe is arranged on the top of the base, and the fixed pipe is fixed to the top of the magnetic widening pipe by using magnetic screws. A control switch for controlling its operation is connected to the bottom of the telescopic drive, and the bottom of the telescopic drive is connected to the magnetic connector. The magnetic connector and the fixed pipe are fixed by using magnetic screws. The upper end of the telescopic pressure arm is fixedly connected to the output shaft of the telescopic drive, and the lower end of the telescopic pressure arm is fixedly connected to the extrusion disc with screws. The extrusion disc is located inside the magnetic widening pipe, and the telescopic drive drives the extrusion disc to perform lifting movements inside the magnetic widening pipe through the telescopic pressure arm; the feeding port is placed on the fixed pipe and is connected to the inside of the magnetic widening pipe, and the extrusion disc is provided with feeding holes corresponding to the feeding port; the pressure sensor is placed on the base, and the pressure sensor is electrically connected to the signal transmission line to sense the degree of extrusion of the telescopic pressure arm; The method comprises the following steps: Step 1: Mg and B powders are mixed in an atomic ratio of 1:2, and ground and mixed in a glove box using a precursor powder mixing device to obtain a precursor powder; the ground precursor powder is packed into a high-density tube using a precursor powder tube loading device, and then assembled into a Cu / Nb / MgB2 single core rod in a Cu / Nb tube, which is processed to a certain size by swaging and drawing; a Nb rod is placed in a Cu tube to be assembled into a Cu / Nb center rod, which is processed to a certain size by swaging or drawing; Step 2: Cu / Nb / MgB2 single core rods and Cu / Nb center rods of the same size are cut to length and cut in sequence, and then placed in a Monel tube to assemble into an "n+m" core composite sheath, where n is the number of Cu / Nb / MgB2 single core rods and m is the number of Cu / Nb center rods; Step 3: The composite sheath is subjected to spinning and drawing processing. During the processing, different processing wire diameters are selected, and then the spinning and drawing processes are continued until the wire is processed to the final finished wire size: Φ0.83mm~Φ1.4mm; Step 4, performing a final heat treatment on the finished wire to obtain a MgB2 multi-core superconducting wire; Among them, the specific method of using the precursor powder tube loading device to load the tube in step 1 is as follows: select a Nb tube of appropriate size for loading, adjust the magnetic widening pipe to an appropriate size according to the selected Nb tube size, place the Nb tube into the magnetic widening pipe, and then select an extrusion disk of appropriate diameter; after the above steps are completed, use the precursor powder obtained in the precursor powder mixing device to add it from the feed port, start the precursor powder tube loading device, and after one extrusion is completed, retract the pressure arm back to the initial position, add precursor powder again, and repeat the above steps to obtain a high-density Nb / MgB2 single-core rod.

2. The method for rapidly preparing high-density MgB2 wire according to claim 1, characterized in that: The upper part of the barrel body is in the shape of a hollow cylinder, and the lower part is in the shape of a hollow cone.

3. The method for rapidly preparing high-density MgB2 wire according to claim 1, characterized in that: The bottom end of the frame is connected with a caster.

4. The method for rapidly preparing high-density MgB2 wire according to claim 1, characterized in that: The barrel cover is flippably connected to the open end of the top of the barrel body through a hinge, and a plurality of lock buckles are provided at positions corresponding to the barrel cover and the barrel body.

5. The method for rapidly preparing high-density MgB2 wire according to claim 1, characterized in that: A handle is welded on the left side of the top end of the barrel cover.

6. The method for rapidly preparing high-density MgB2 wire according to claim 1, characterized in that: An alloy upper cover is welded and fixed on the telescopic driver.

7. The method for preparing a high-density MgB2 superconducting wire according to claim 1, wherein: The specific implementation method of using the precursor powder mixing device to mix the precursor powder in step 1 is as follows: open the barrel cover in the precursor powder mixing device, use an electronic balance to weigh Mg and B powders with an atomic ratio of 1:2, pour them into the precursor powder mixing device, start the motor, and rotate the stirring blade at high speed for a predetermined time to obtain a mixed precursor powder.

8. The method for preparing a high-density MgB2 superconducting wire according to claim 1, wherein: The specific method of performing the final heat treatment on the finished wire in step 4 is: heating the wire to 560°C~670°C in an inert gas environment for 30min~60min and keeping it at this temperature for 1h~4h.

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