A single-turn coil type destructive pulsed magnet

Abstract

This application belongs to the technical field of pulsed high magnetic fields, and specifically discloses a single-turn coil type destructive pulsed magnet. The pulsed magnet includes: a magnet coil and two parallelly arranged discharge electrode plates; the magnet coil is a single-turn coil, and the single-turn coil includes an outer metal layer and an inner metal layer connected in sequence. The electrical conductivity of the inner metal layer is less than that of the outer metal layer, and in the radial direction perpendicular to the central axis passing through the single-turn coil, the first thickness of the inner metal layer is less than the second thickness of the outer metal layer; both ends of the single-turn coil are respectively connected to one of the discharge electrode plates for coil discharging. Through this application, the heat conduction process from the inner surface of the coil to the air domain can be effectively inhibited, preventing thermal damage to the sample within the coil aperture; at the same time, the situation where the magnetic field generated at the center point of the coil decreases can be prevented, ensuring the test performance.

Description

Technical Field

[0001] The present application belongs to the technical field of pulsed high magnetic field, and more specifically, relates to a single-turn coil type destructive pulse magnet. Background Art

[0002] A single-turn magnet coil is a destructive pulse magnet. Since the current generated during its discharge reaches hundreds of kiloamperes to several megaamperes, it can produce an ultra-strong pulse magnetic field. It has become a cutting-edge research hotspot in the fields of condensed matter physics and superconducting materials.

[0003] In the prior art, when conducting a magnetic coil discharge test, due to the extremely large coil discharge current, the Joule heat power deposited on the magnetic coil of only a few millimeters in size during discharge is as high as the gigawatt (GW) level, causing a sharp temperature rise in the coil and the surrounding air. At the same time, since the samples in the coil aperture are usually made of polyimide insulation material, whose thermal damage temperature is only a few hundred degrees Celsius, the samples are easily thermally damaged by the single-turn coil during discharge, resulting in damage to the samples. When the inner diameter of the magnetic coil becomes smaller and the distance between the sample and the inner surface of the magnetic coil becomes smaller, the above-mentioned thermal damage effect will become more obvious.

[0004] Therefore, how to effectively suppress the thermal damage generated during the discharge process of the magnet coil has become a technical problem that needs to be urgently solved in the industry. Summary of the invention

[0005] In view of the defects of the prior art, the present application aims to solve the problem that the prior art cannot effectively suppress the thermal damage generated during the discharge process of the magnet coil.

[0006] To achieve the above objectives, the present application provides a single-turn coil destructive pulse magnet, comprising:

[0007] A magnet coil and two discharge electrode plates arranged in parallel;

[0008] The magnetic coil is a single-turn coil, comprising an outer metal layer and an inner metal layer connected in sequence, the conductivity of the inner metal layer is less than the conductivity of the outer metal layer, and in a radial direction perpendicular to a central axis passing through the single-turn coil, a first thickness of the inner metal layer is less than a second thickness of the outer metal layer;

[0009] Two ends of the single-turn coil are respectively connected to a discharge electrode plate for coil discharge.

[0010] According to a single-turn coil destructive pulse magnet provided by the present application, in the direction passing through the central axis of the single-turn coil, the first height of the inner metal layer is the same as the second height of the outer metal layer.

[0011] A single-turn coil type destructive pulse magnet provided by the present application, the value range of the first thickness of the inner metal layer is from 0.1 millimeter to 0.3 millimeters.

[0012] A single-turn coil type destructive pulse magnet provided by the present application, the second thickness of the outer metal layer is not less than 2 millimeters.

[0013] A single-turn coil type destructive pulse magnet provided by the present application, the conductor density of the inner metal layer is greater than that of the outer metal layer.

[0014] A single-turn coil type destructive pulse magnet provided by the present application, the conductivity of the inner metal layer is less than that of the outer metal layer by at least one order of magnitude.

[0015] A single-turn coil type destructive pulse magnet provided by the present application, the melting and boiling points of the inner metal layer are higher than those of the outer metal layer.

[0016] A single-turn coil type destructive pulse magnet provided by the present application, the conductor material of the inner metal layer is tungsten or tantalum, and the conductor material of the outer metal layer is copper.

[0017] A single-turn coil type destructive pulse magnet provided by the present application, the connection method between the outer metal layer and the inner metal layer includes mechanical connection, or chemical connection, or welding.

[0018] A single-turn coil type destructive pulse magnet provided by the present application, the shapes and sizes of the two discharge electrode plates are the same, and their projections overlap in the direction perpendicular to the parallel direction of the electrode plates.

[0019] Generally speaking, compared with the prior art through the above technical solutions conceived by the present application, the following beneficial effects are obtained:

[0020] A single-turn coil type destructive pulse magnet provided by the present application. The pulse magnet includes a magnet coil and two parallel arranged discharge electrode plates. Among them, the magnet coil is a single-turn coil, and the magnet coil includes an outer metal layer and an inner metal layer connected in sequence. The conductivity of the inner metal layer is less than that of the outer metal layer, and in the radial direction of the coil, the thickness of the inner metal layer is less than that of the outer metal layer. The two ends of the single-turn coil are respectively connected to a discharge electrode plate for coil discharging. Through the above structural arrangement, when the coil discharges, since the conductivity of the inner metal layer is less than that of the outer metal layer, the current density mainly flows through the outer metal layer, making the inner metal layer have a lower current density and temperature rise, thereby effectively suppressing the heat conduction process from the inner surface of the coil to the air domain and preventing thermal damage to the sample in the coil aperture. At the same time, since the thickness of the inner metal layer is less than that of the outer metal layer, it can effectively prevent the equivalent distance between the discharge current flowing through the coil and the center point of the coil from becoming larger and the magnetic field generated by the center point of the coil from decreasing, improving the test performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is one of the schematic structural diagrams of the single-turn coil type destructive pulse magnet provided by the present application;

[0022] Figure 2 is the second schematic structural diagram of the single-turn coil type destructive pulse magnet provided by the present application;

[0023] Figure 3 is a schematic comparison diagram of the temperature control results of the single-turn coil type destructive pulse magnet provided by the present application and a traditional pulse magnet.

[0024] In all the drawings, the same reference numerals are used to represent the same elements or structures, where:

[0025] 100: coil magnet; 101: central axis of the magnet coil; 110: outer metal layer; 120: inner metal layer; 130: two ends of the magnet coil; 200: discharge electrode plate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0027] The terms "first" and "second" etc. in the description and claims of this article are used to distinguish different objects, rather than to describe a specific order of the objects. For example, the first response message and the second response message etc. are used to distinguish different response messages, rather than to describe a specific order of the response messages.

[0028] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0029] The embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application.

[0030] Figure 1 is one of the structural schematic diagrams of the single-turn coil type destructive pulsed magnet provided by the present application. It is a structural schematic diagram from the perspective of the axial direction of the coil, as Figure 1 shown, the pulsed magnet includes:

[0031] a magnet coil 100 and two parallel discharge electrode plates 200;

[0032] The magnet coil 100 is a single-turn coil. The single-turn coil includes an outer metal layer 110 and an inner metal layer 120 connected in sequence. The conductivity of the inner metal layer 120 is less than that of the outer metal layer 110, and in the radial direction perpendicular to the central axis 101 passing through the single-turn coil, the first thickness of the inner metal layer 120 is less than the second thickness of the outer metal layer 110.

[0033] Both ends 130 of the single-turn coil are respectively connected to a discharge electrode plate 200 for coil discharge.

[0034] In the embodiments of the present application, considering that when the coil discharges, the air around the coil, rather than the coil itself, is in direct contact with the sample. Therefore, in order to prevent thermal damage to the sample as much as possible, the heating mechanism of the gas around the coil should be clarified first. After research, this mechanism mainly includes: First, the temperature of the coil during discharge can reach several thousand or even tens of thousands of degrees Celsius. The air can absorb heat from the inner surface of the coil under the action of heat conduction and heat convection and transfer it to the sample; Second, the high-temperature air itself will be ionized and have a certain conductivity. Since there is direct contact between the high-temperature air and the inner surface of the coil with the highest current density, the air can directly shunt the current flowing through the coil and is thus rapidly heated by the Joule heat of the current.

[0035] All in all, the fundamental reason for gas heating is the direct contact between the gas and the coil. To block the occurrence of thermal damage to the sample from the mechanism, it is necessary to isolate the contact between the outer conductor with high conductivity and the air inside the coil. For this purpose, the present application provides a single-turn coil type destructive pulsed magnet as described above to solve the above defects.

[0036] Specifically, in the embodiments of the present application, the radial direction refers to the direction extending outward along the radius of the coil, which is perpendicular to the axial direction. Here, the axial direction refers to the direction passing through the central axis of the magnet coil.

[0037] The first thickness described in the embodiments of the present application refers to the thickness of the inner metal layer in the radial direction of a single-turn coil.

[0038] The second thickness described in the embodiments of the present application refers to the thickness of the outer metal layer in the radial direction of a single-turn coil.

[0039] In the embodiments of the present application, a coil-type destructive pulsed magnet is designed. The pulsed magnet includes a magnet coil and two parallelly arranged discharge electrode plates. Among them, the magnet coil is a single-turn coil, and the single-turn coil includes an outer metal layer and an inner metal layer connected in sequence, which is a double-layer metal layer structure. Here, the conductivity of the inner metal layer is less than that of the outer metal layer, and in the radial direction perpendicular to the central axis passing through the single-turn coil, the first thickness D1 of the inner metal layer is less than the second thickness D2 of the outer metal layer.

[0040] In the embodiments of the present application, the discharge electrode plates include two electrode plates arranged in parallel. One side is connected to the pulsed capacitor bank power supply, and the other side is connected to the magnet coil. The two ends of the coil are respectively connected to one discharge electrode plate to form a discharge circuit, so as to discharge through the magnet coil. When the pulsed capacitor bank power supply discharges, a very large discharge current will flow through the magnet coil, generating an ultra-strong pulsed magnetic field at the center of the coil. Thus, it can act on the test sample to detect the magnetization performance.

[0041] In the embodiments of the present application, it is necessary to set the conductivity of the inner metal layer to be less than that of the outer metal layer. In this way, the current density of the discharge current can be controlled to mainly flow through the outer conductor as much as possible, rather than the inner conductor. Otherwise, the current density of the discharge current will mainly flow through the inner conductor, causing a sharp temperature rise in the inner conductor, thereby increasing the air temperature near the inner surface of the coil, which is not conducive to suppressing the thermal destruction effect of the coil.

[0042] In the embodiments of the present application, in the radial direction of the coil, the thickness D1 of the inner metal layer must be less than the thickness D2 of the inner layer of the outer metal layer. For example, the thickness of the outer metal layer conductor can be set to ten times or more of the thickness of the inner metal layer conductor. This is because the inner metal layer conductor has a lower conductivity and a smaller current density, and the discharge current mainly flows through the outer metal layer conductor. If the inner metal layer conductor is thicker, the equivalent distance between the discharge current flowing through the coil and the center point of the coil will increase, resulting in a significant decrease in the magnetic field generated at the center point of the coil, which is not conducive to the detection of the sample inside the coil.

[0043] The single-turn coil type destructive pulse magnet according to the embodiment of the present application. The pulse magnet includes a magnet coil and two parallel arranged discharge electrode plates. Among them, the magnet coil is a single-turn coil, and the magnet coil includes an outer metal layer and an inner metal layer connected in sequence. The conductivity of the inner metal layer is less than that of the outer metal layer, and in the coil radial direction, the thickness of the inner metal layer is less than that of the outer metal layer. The two ends of the single-turn coil are respectively connected to a discharge electrode plate for coil discharge. Through the above structural arrangement, when the coil discharges, since the conductivity of the inner metal layer is less than that of the outer metal layer, the current density mainly flows through the outer metal layer, making the inner metal layer have a lower current density and temperature rise, thereby effectively suppressing the heat conduction process from the inner surface of the coil to the air domain and reducing the thermal damage to the sample inside the coil aperture. At the same time, since the thickness of the inner metal layer is less than that of the outer metal layer, it can effectively prevent the equivalent distance between the discharge current flowing through the coil and the coil center point from becoming larger and the magnetic field generated by the coil center point from decreasing, ensuring the test performance.

[0044] Figure 2 is the second structural schematic diagram of the single-turn coil type destructive pulse magnet provided by the present application. It is a structural schematic diagram analyzed from the perspective of the coil radial direction, as Figure 2 shown. In the embodiment of the present application, in the direction of the central axis 101 passing through the single-turn coil, the first height of the inner metal layer 120 is the same as the second height of the outer metal layer 110. Among them, it should be noted that for the convenience of describing the double-layer metal layer structure of the magnet coil 100, Figure 2 a truncation process is performed on the magnet coil. In fact, the magnet coil 100 is a complete coil shape, and there are only open spaces at its two ends 130 (not marked in the figure) for arranging two discharge electrode plates 200 and connecting each end to the corresponding plate respectively.

[0045] Specifically, the first height described in the embodiment of the present application refers to the height between the upper and lower surfaces of the inner metal layer in the coil axial direction.

[0046] The second height described in the embodiment of the present application refers to the height between the upper and lower surfaces of the outer metal layer in the coil axial direction.

[0047] Optionally, in the embodiment of the present application, in the direction of the central axis passing through the single-turn coil, the first height of the inner metal layer and the second height of the outer metal layer may not be the same. The arranged inner metal layer can play a certain blocking role and to a certain extent play a role in suppressing the heat conduction process from the inner surface of the coil to the air domain and reducing the thermal damage to the sample. However, the effect achieved is not ideal.

[0048] In the embodiments of the present application, through research, it is found that when the axial height of the inner-layer metal layer conductor is greater than that of the outer-layer metal layer conductor, the inner-layer metal layer conductor is prone to premature damage. At the same time, when the axial height of the inner-layer metal layer conductor is less than the axial height of the outer-layer metal layer conductor, since the inner-layer metal layer cannot completely shield the outer-layer metal layer, the isolation effect of the inner-layer metal layer is greatly reduced, resulting in the inability to effectively achieve thermal isolation and electrical isolation between the inner surface of the outer conductor and the air domain. Therefore, along the coil axis, the height of the inner-layer metal layer needs to be set to be the same as that of the outer-layer metal layer, both being H0.

[0049] For the single-turn coil type destructive pulsed magnet in the embodiments of the present application, by setting the height of the inner-layer metal layer to be the same as that of the outer-layer metal layer along the coil axis, premature damage to the inner-layer metal layer conductor can be prevented, the isolation effect of the inner-layer metal layer can be enhanced, the effect of suppressing the heat conduction process from the inner surface of the coil to the air domain can be further improved, and the thermal damage to the sample within the coil aperture can be further reduced.

[0050] Based on the content of the above embodiments, as an alternative embodiment, the value range of the first thickness of the inner-layer metal layer is 0.1 millimeter to 0.3 millimeters (mm).

[0051] Specifically, in the embodiments of the present application, along the coil radial direction, the value range of the first thickness of the inner-layer metal layer is 0.1 mm to 0.3 mm. For example, it can specifically take a value of 0.1 mm.

[0052] For the single-turn coil type destructive pulsed magnet in the embodiments of the present application, by restricting the value range of the first thickness of the inner-layer metal layer between 0.1 mm and 0.3 mm, it can be ensured that the space occupancy rate within the magnet coil is small, the assembly of the test sample within the coil is more convenient, and it is beneficial to improve the convenience of sample detection within the coil.

[0053] Based on the content of the above embodiments, as an alternative embodiment, the second thickness of the outer-layer metal layer is not less than 2 mm.

[0054] Specifically, in the embodiments of the present application, the thickness of the outer-layer metal layer conductor cannot be too small, otherwise the outer-layer metal layer will deform at an extremely high speed due to the strong electromagnetic force, causing its mechanical damage to occur earlier than the magnetic field peak and reducing the magnetic field magnitude of the single-turn coil.

[0055] More specifically, along the coil radial direction, the second thickness of the outer-layer metal layer is not less than 2 mm, and it can specifically take a value of 2.9 mm.

[0056] In the single-turn coil type destructive pulse magnet according to the embodiment of the present application, by restricting the value range of the second thickness of the outer metal layer to be above 2 mm, it is possible to effectively avoid the situation where the outer metal layer is deformed at an extremely high speed due to being too thin under the action of a strong electromagnetic force, and further avoid the reduction of the magnetic field of the single-turn coil, thereby improving the stability of the magnetic field inside the coil.

[0057] Based on the content of the above embodiment, as an alternative embodiment, the conductor density of the inner metal layer is greater than that of the outer metal layer.

[0058] Specifically, in the embodiment of the present application, when the conductor density of the inner metal layer is not greater than that of the outer metal layer, it will cause premature damage to the conductor of the inner metal layer and reduce its thermal isolation and electrical isolation effects.

[0059] Therefore, in this embodiment, the conductor density of the inner metal layer can be further set to be greater than that of the outer metal layer.

[0060] In the single-turn coil type destructive pulse magnet according to the embodiment of the present application, by setting the conductor density of the inner metal layer to be greater than that of the outer metal layer, it is possible to effectively avoid the situation of premature damage to the conductor of the inner metal layer, improve the thermal isolation and electrical isolation effects of the inner metal layer, and further reduce the thermal damage to the sample inside the coil aperture.

[0061] Based on the content of the above embodiment, as an alternative embodiment, the conductivity of the inner metal layer is at least one order of magnitude less than that of the outer metal layer.

[0062] It should be noted that in the embodiment of the present application, the conductivity of the inner metal layer must be less than that of the outer metal layer. Otherwise, the current density will still mainly flow through the inner metal layer, resulting in a sharp temperature rise of the inner conductor and an increase in the air temperature near the inner surface of the coil, which is not conducive to suppressing the heat conduction from the inner surface of the coil to the air domain.

[0063] In the embodiment of the present application, the conductivity of the inner conductor can be set to be much lower than that of the outer conductor. Specifically, the conductivity of the inner metal layer is at least one order of magnitude less than that of the outer metal layer. For example, it can be set that even if the conductivity of the inner metal layer is increased by ten times, the result is still less than the conductivity of the outer metal layer.

[0064] In the single-turn coil type destructive pulse magnet according to the embodiment of the present application, by setting the conductivity of the inner metal layer to be at least one order of magnitude less than that of the outer metal layer, the suppression effect is improved, the current density mainly flows through the outer metal layer, the sharp temperature rise of the conductor of the inner metal layer is prevented, and the increase in the air temperature near the inner surface of the coil is prevented, further improving the suppression of the heat conduction from the inner surface of the coil to the air domain.

[0065] Based on the content of the above embodiments, as an alternative embodiment, the melting and boiling points of the inner metal layer are higher than those of the outer metal layer.

[0066] It should be noted that it has been found that the heating mechanism of the gas around the coil also includes the following: Thirdly, the large current flowing through a single-turn coil during discharge will rapidly vaporize the inner surface of the coil and form a plasma jet, which has a very high speed and temperature. Once it contacts the sample, it will immediately cause ablation of the sample.

[0067] In some embodiments, under the condition that the melting and boiling points of the inner metal layer are not higher than those of the outer metal layer, when the coil discharges, the inner metal layer will be affected by the plasma jet formed by the outer metal layer. As the coil discharge progresses, the inner metal layer will be gradually damaged. Nevertheless, the inner metal layer still plays a certain blocking role. To further enhance the thermal isolation effect of the inner metal layer, it is necessary to optimize the melting and boiling points of the inner metal layer.

[0068] Therefore, in the embodiments of the present application, further, the melting and boiling points of the inner metal layer can be set higher than those of the outer metal layer to enhance the thermal isolation and electrical isolation effects of the inner metal layer.

[0069] The single-turn coil type destructive pulsed magnet of the embodiments of the present application, by setting the melting and boiling points of the inner metal layer higher than those of the outer metal layer, enables the inner metal layer to block the plasma jet formed by the outer metal layer from reaching the sample surface, and can effectively inhibit the ionization and discharge of air, thereby further enhancing the thermal isolation and electrical isolation effects.

[0070] Based on the content of the above embodiments, as an alternative embodiment, the conductor material of the inner metal layer is tungsten or tantalum, and the conductor material of the outer metal layer is copper.

[0071] Specifically, in the embodiments of the present application, for the selection of the conductor materials of the inner metal layer and the outer metal layer, it is necessary to satisfy: the conductivity of the inner metal layer is less than that of the outer metal layer by at least one order of magnitude, the conductor density of the inner metal layer is greater than that of the outer metal layer, and the melting and boiling points of the inner metal layer are higher than those of the outer metal layer. Tungsten or tantalum can be used to make the inner metal layer, and copper can be used to make the outer metal layer.

[0072] In the embodiments of the present application, when the magnet coil discharges, since the conductivity of the outer copper conductor is higher than that of the inner tungsten or tantalum conductor by one order of magnitude, therefore, the current density mainly flows through the outer copper conductor. The copper conductor rapidly heats up and vaporizes under the action of Joule heat. The inner tungsten or tantalum conductor can maintain a lower temperature than the outer copper conductor due to the lower current density, and due to the larger conductor density, it enhances the thermal isolation and electrical isolation effects on the inner surface of the outer conductor and the air domain.

[0073] Meanwhile, although the drastic temperature rise of the outer copper conductor will cause the copper conductor to vaporize and form a plasma jet, the inner tungsten or tantalum conductor has a very high melting and boiling point, which can further block the plasma jet formed by the outer copper conductor from reaching the sample surface and further effectively inhibit the ionization and discharge of air. Eventually, through the dual effects of thermal isolation and electrical isolation, the heating of the air inside the coil is controlled within a reasonable range to prevent the sample from being thermally damaged.

[0074] In the single-turn coil type destructive pulsed magnet according to the embodiment of the present application, by using tungsten or tantalum to make the inner metal layer of the magnet coil and copper to make the outer metal layer of the magnet coil, when the magnet coil discharges, the inner metal layer can play a good role in thermal isolation and electrical isolation, and can reasonably control the heating degree of the air inside the coil, better preventing the occurrence of sample thermal damage.

[0075] Based on the content of the above embodiment, as an optional embodiment, the connection method between the outer metal layer and the inner metal layer includes mechanical connection, or chemical connection, or welding.

[0076] Specifically, in the embodiment of the present application, various means including mechanical connection and chemical connection can be used to connect the outer metal layer and the inner metal layer of the pulsed magnet to ensure that the two conductor layers are firmly fixed and adhered to prevent detachment.

[0077] Among them, mechanical connection mainly uses mechanical principles to firmly connect the metal layers together. The mechanical connection methods adopted can include caulking.

[0078] Here, caulking is to reduce and closely fit the gap between the metal layers by means of extrusion or hammering, etc., so as to achieve connection. This method is usually suitable for the connection of relatively thin metal layers.

[0079] Among them, welding is to make the metal layers melt and fuse with each other through high temperature to achieve permanent connection. Specific welding methods can include: fusion welding, pressure welding, etc.

[0080] Here, fusion welding is to heat the two metal layers to the melting state by using heat sources such as electric arc and laser, and then cool and solidify to form a weld seam. Fusion welding has high connection strength and sealing performance, and is suitable for the connection of various metal materials.

[0081] Pressure welding is to make the two metal layers contact and undergo plastic deformation under pressure to achieve connection. Pressure welding includes various types such as resistance welding and friction welding, and is suitable for the connection of metal layers with different materials and thicknesses.

[0082] Among them, chemical connection usually bonds metal layers together using adhesives. This connection method does not require complex equipment and processes, is simple and convenient to operate, and is applicable to the connection of metal layers of various materials and shapes. However, the strength and durability of chemical connection may be inferior to those of mechanical connection and welding.

[0083] The single-turn coil type destructive pulsed magnet of the embodiment of the present application realizes the fixed connection between two metal layers of the pulsed magnet through mechanical connection, or chemical connection, or welding. The processing is simple and the effect is reliable, which is beneficial to improving the convenience of manufacturing the pulsed magnet.

[0084] Continue to refer to Figure 1 and Figure 2 , in the embodiment of the present application, the shapes and sizes of the two discharge electrode plates 200 are the same, and their projections overlap in the direction perpendicular to the parallel direction of the electrode plates.

[0085] Specifically, in the embodiment of the present application, it is set that the shapes, sizes and thicknesses of the two discharge electrode plates are the same, and their projections overlap in the direction perpendicular to the parallel direction of the electrode plates. That is to say, the two discharge electrode plates are arranged in parallel alignment in a specific direction. Through the above-mentioned parallel-aligned electrode plate layout, the following effects can be brought:

[0086] On the one hand, it can reduce the resistance during the transmission of the discharge current, so that the current can flow more stably; on the other hand, the parallel-aligned electrode plate layout makes the structure more compact and regular, which is convenient for the installation and maintenance of the electrode plates during the detection process.

[0087] Optionally, in the embodiment of the present application, a single-turn coil type destructive pulsed magnet is provided, which includes a magnet coil and two discharge electrode plates arranged in parallel alignment; the shapes and sizes of the two discharge electrode plates are the same; the magnet coil is a single-turn coil, and the two ends of the single-turn coil are respectively connected to a discharge electrode plate for coil discharge.

[0088] Among them, the single-turn coil includes an outer metal layer and an inner metal layer connected in sequence. The conductor material of the outer metal layer is copper, and the conductor material of the inner metal layer is tungsten or tantalum to ensure that the conductivity of the inner metal layer is at least one order of magnitude less than that of the outer metal layer, and the conductor density of the inner metal layer is greater than that of the outer metal layer, and the melting and boiling points of the inner metal layer are higher than those of the outer metal layer.

[0089] In this embodiment, in the direction of the central axis passing through the single-turn coil, the height of the inner tungsten or tantalum metal layer is the same as that of the outer copper metal layer, and in the radial direction perpendicular to the central axis passing through the single-turn coil, the thickness of the inner tungsten or tantalum metal layer is less than that of the outer copper metal layer. The thickness of the inner tungsten or tantalum metal layer ranges from 0.1 mm to 0.3 mm, and the thickness of the outer copper metal layer is not less than 2 mm. The two layers of conductors are tightly fixed and adhered to prevent detachment.

[0090] In a specific embodiment of the present application, the inner diameter of the magnet coil is 4.0 mm, the axial height is 3.0 mm, the radial thickness is 3.0 mm, the thickness of the inner tungsten metal layer is 0.1 mm, and the thickness of the outer copper metal layer is 2.9 mm.

[0091] Figure 3 It is a schematic comparison diagram of the temperature control results of the single-turn coil type destructive pulse magnet and the traditional pulse magnet provided by the present application, which is the temperature detection result at a position 0.1 mm inside the inner surface of the coil on the central plane of the coil. As Figure 3 shown, in the embodiment of the present application, the pulse magnet is a double-layer tungsten-copper conductor coil, and the traditional pulse magnet is a single-layer copper conductor coil. From the results in the figure, it can be seen that when the discharge peak current reaches 900 kA and the current rise time gradually reaches 1.4 microseconds, the temperature inside the inner surface of the traditional single-layer copper conductor coil rises sharply and finally exceeds 500 K. However, the double-layer tungsten-copper conductor coil provided by the present application can control the temperature inside the inner surface of the coil below 340 K, effectively suppressing the sharp temperature rise and heat generation of the air inside the coil and preventing the sample from being thermally damaged, with excellent effects.

[0092] It should be understood that expressions such as "including" and "may include" that can be used in the present application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In the present application, terms such as "including" and / or "having" can be interpreted as indicating a specific characteristic, number, operation, constituent element, component, or a combination thereof, but cannot be interpreted as excluding the existence or possibility of addition of one or more other characteristics, numbers, operations, constituent elements, components, or a combination thereof.

[0093] In the description of the embodiments of the present application, it should be noted that unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. Among them, "fixed connection" means that the two are connected and the relative position relationship after connection remains unchanged. "Rotational connection" means that the two are connected and can rotate relative to each other after connection. "Sliding connection" means that the two are connected and can slide relative to each other after connection. The orientation terms mentioned in the embodiments of the present application, such as "top", "bottom", "inside", "outside", "left", "right", etc., are only references to the direction of the accompanying drawings. Therefore, the orientation terms are used to better and more clearly illustrate and understand the embodiments of the present application, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation on the embodiments of the present application.

[0094] In addition, in the embodiments of the present application, mathematical concepts such as symmetry, equality, parallelism, and perpendicularity are mentioned. These limitations are all in view of the current technological level, rather than the absolutely strict definitions in the mathematical sense, and a small deviation is allowed. Approximations to symmetry, equality, parallelism, perpendicularity, etc. are all acceptable. For example, when it is said that A is parallel to B, it means that A is parallel to B or approximately parallel to B, and the included angle between A and B can be between 0 degrees and 10 degrees. When it is said that A is perpendicular to B, it means that A is perpendicular to B or approximately perpendicular to B, and the included angle between A and B can be between 80 degrees and 100 degrees.

[0095] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A single-turn coil destructive pulse magnet, characterized in that: include: A magnet coil and two discharge electrode plates arranged in parallel; The magnetic coil is a single-turn coil, comprising an outer metal layer and an inner metal layer connected in sequence, the conductivity of the inner metal layer is less than the conductivity of the outer metal layer, and in a radial direction perpendicular to a central axis passing through the single-turn coil, a first thickness of the inner metal layer is less than a second thickness of the outer metal layer; Two ends of the single-turn coil are respectively connected to a discharge electrode plate for coil discharge.

2. The single-turn coil destructive pulse magnet according to claim 1, characterized in that: In a direction passing through a central axis of the single-turn coil, a first height of the inner metal layer is the same as a second height of the outer metal layer.

3. The single-turn coil destructive pulse magnet according to claim 1, characterized in that: The first thickness of the inner metal layer ranges from 0.1 mm to 0.3 mm.

4. The single-turn coil destructive pulse magnet according to claim 1, characterized in that: The second thickness of the outer metal layer is not less than 2 mm.

5. The single-turn coil destructive pulse magnet according to claim 1, characterized in that: The conductor density of the inner metal layer is greater than the conductor density of the outer metal layer.

6. The single-turn coil destructive pulse magnet according to claim 5, characterized in that: The electrical conductivity of the inner metal layer is at least one order of magnitude lower than the electrical conductivity of the outer metal layer.

7. The single-turn coil destructive pulse magnet according to claim 6, characterized in that: The melting and boiling points of the inner metal layer are higher than those of the outer metal layer.

8. The single-turn coil destructive pulse magnet according to claim 7, characterized in that: The conductor material of the inner metal layer is tungsten or tantalum, and the conductor material of the outer metal layer is copper.

9. The single-turn coil destructive pulse magnet according to any one of claims 1 to 8, characterized in that: The outer metal layer and the inner metal layer are connected by mechanical connection, chemical connection or welding.

10. The single-turn coil destructive pulse magnet according to any one of claims 1 to 8, characterized in that: The two discharge electrode plates have the same shape and size, and their projections in a direction perpendicular to the direction parallel to the electrode plates overlap.

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