Superconducting strip structure for improving resistance of superconducting constant-current switch and manufacturing method

Abstract

The invention provides a superconducting tape structure for improving the resistance of a superconducting constant-current switch and a manufacturing method, the superconducting tape structure comprises a conductive layer, a superconducting layer, a buffer layer and a substrate layer, and the substrate layer, the buffer layer and the superconducting layer are stacked in sequence; the surface, deviating from the buffer layer, of the superconducting layer comprises at least two conductive layers arranged at intervals in the direction of the strip, and a superconducting path used for communicating the two conductive layers is arranged on the superconducting layer. According to the superconductive constant-current switch, the superconductive path is arranged on the superconductive layer between the two conductive layers, so that current can only flow from one conductive layer to the other conductive layer through the superconductive path, and the whole superconductive constant-current switch can present relatively large resistance, is small in structure and is fast in switching by utilizing the characteristic that the superconductive layer can present relatively large resistance in a non-superconductive state. The conduction sectional area of the superconducting path is reduced, the path length of the superconducting path is increased, and the resistance of the superconducting constant-current switch when the switch is turned on is further increased.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting tape structure design, and in particular to a superconducting tape structure for improving the resistance of a superconducting constant current switch and a manufacturing method thereof. Background Art

[0002] Superconducting constant current switches use the critical properties of superconducting tapes to achieve the transition between "on" and "off" states. Superconducting materials have three critical parameters: temperature, current, and magnetic field. Therefore, according to the transition conditions, superconducting constant current switches can be divided into three types: thermal control, flow control, and field triggered.

[0003] like Figure 1 The structure of the second generation high temperature superconducting tape includes a conductive layer, a superconducting layer and a base layer. The conductive layer is a single layer or multiple layers. The material of the conductive layer is copper and / or silver. The material of the superconducting layer is preferably REBCO. Below the superconducting layer is a buffer layer, which is a dielectric material for basic insulation. Below the buffer layer is a base layer, which is mostly made of Hastelloy. Among them, copper and / or silver are wrapped in the outermost layer, including the upper and lower surfaces and the sides. After the superconducting layer in the tape is converted into a non-superconducting state, since the resistance of the superconducting layer after quenching is greater than that of the copper layer and / or silver layer at the same temperature, the current originally flowing through the superconducting layer will be largely diverted to the copper layer and / or silver layer wrapped around it.

[0004] like Figure 2 As shown in the equivalent circuit, since it is difficult to directly excite a superconducting closed-loop coil, it is usually necessary to use a superconducting constant current switch to temporarily "open" the coil loop to form a similar open circuit (not a complete open circuit, the resistance of a complete open circuit is infinite, the similar open circuit here means that there is still a certain resistance value at both ends of the switch), so that the power supply can excite the superconducting coil.

[0005] Since the superconducting constant current switch itself is also part of the closed-loop coil, when excited, the superconducting tape in the superconducting constant current switch is not really open, but is transformed into a non-superconducting state. At this time, the large resistance presented by the superconducting constant current switch is also compared with the extremely small resistance of the superconductor, so it is more accurate to regard the superconducting constant current switch as a variable resistor. During the charging process, the greater the resistance presented to the outside by the superconducting constant current switch, the better, so that the external DC power supply can have more current flowing into the coil during the process of exciting the superconducting magnet, reducing the shunt through the superconducting constant current switch. This is conducive to reducing Joule heat, which is particularly important for superconducting magnets that require a low-temperature environment.

[0006] At present, the method of increasing the resistance of a thermally controlled superconducting constant current switch is to increase the resistance by lengthening the superconducting tape used to make the superconducting constant current switch. This method uses a large amount of tape and is costly. The resulting superconducting constant current switch is large in size, resulting in a large heat capacity. As a result, the speed of the superconducting switch switching between the resistive state and the non-resistive state is relatively slow, which is not conducive to the thermal stability of the low-temperature cavity and there is room for improvement. Summary of the invention

[0007] In view of the defects in the prior art, the object of the present invention is to provide a superconducting tape structure and a manufacturing method for improving the resistance of a superconducting constant current switch.

[0008] A superconducting tape structure for improving the resistance of a superconducting constant current switch provided by the present invention comprises a conductive layer, a superconducting layer, a buffer layer and a base layer, wherein the base layer, the buffer layer and the superconducting layer are stacked in sequence; the surface of the superconducting layer facing away from the buffer layer comprises at least two conductive layers arranged at intervals along the direction of the tape, and a superconducting path for connecting the two conductive layers is arranged on the superconducting layer.

[0009] Preferably, the superconducting path extends from one conductive layer to another conductive layer; the superconducting path includes continuous regular straight line segments, connected regular arc segments and / or irregular shape segments.

[0010] Preferably, the superconducting path is formed by material reduction in the superconducting layer and / or by physical isolation in the superconducting layer, the current is transmitted along the direction of the tape, and the current flows from one of the conductive layers to another conductive layer along the direction of the superconducting path.

[0011] Preferably, the superconducting layer is provided with groove lines, the depth of the groove lines is greater than or equal to the thickness of the superconducting layer; and the superconducting path is formed by being fully or partially surrounded by the groove lines.

[0012] Preferably, the superconducting layer is provided with reduced material areas on both sides along the length direction and / or the width direction of the tape; and the superconducting path is formed entirely or partially by reducing material in the superconducting layer.

[0013] Preferably, the conductive layer comprises a silver covering layer and / or a copper stabilizing layer; and the area of ​​the conductive layer is smaller than or equal to the area of ​​the superconducting layer.

[0014] Preferably, the conductive layer covers a surface of the base layer facing away from the buffer layer.

[0015] According to a method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch provided by the present invention, the manufacturing method comprises the following steps:

[0016] Step S1, prepare a superconducting tape for standby use;

[0017] Step S2, removing unnecessary conductive layers;

[0018] Step S3: destroy or remove unnecessary superconducting layers, and form a superconducting path between two adjacent conductive layers.

[0019] Preferably, the method for removing the unnecessary conductive layer or superconducting layer in step S3 comprises chemical etching and / or mechanical processing.

[0020] Preferably, when the side of the tape is wrapped with a superconducting layer, after removing the silver covering layer and / or the copper stabilizing layer on the superconducting layer, the silver covering layer and / or the copper stabilizing layer on the side of the superconducting tape are removed at the same time, and then the superconducting layer to be reduced is destroyed or removed.

[0021] Preferably, for step S3, grooves may be processed on the superconducting layer to form a superconducting path between two adjacent conductive layers.

[0022] Preferably, for step S3, the unnecessary superconducting layer may be destroyed or removed, and grooves may be processed on the superconducting layer to form a superconducting path; the method of reducing the unnecessary conductive layer or superconducting layer includes chemical etching and / or mechanical processing.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The present invention sets a superconducting path on the superconducting layer between two conductive layers so that the current can only flow from one conductive layer to the other conductive layer through the superconducting path. In this way, the characteristic that the superconducting layer presents a large resistance in a non-superconducting state can be utilized, so that the entire superconducting constant current switch will present a large resistance, a small structure and fast switching.

[0025] 2. The present invention cuts off the electrical connection between the two sides of the tape to ensure that most of the current flows on the superconducting layer side of the superconducting tape. When the shunt current during excitation flows through the superconducting layer side of the superconducting tape, the current will flow through the gap between the two conductive layers on the side of the superconducting layer away from the buffer layer. Since the buffer layer below the superconducting layer is basically insulated and the superconducting layer will present a large resistance in the non-superconducting state, the entire superconducting constant current switch will present a large resistance.

[0026] 3. The present invention can form a reduced material area by removing the material on the peripheral edge of the superconducting layer to further increase the resistance of the superconducting constant current switch when it is turned on, and further remove the exposed area of ​​the superconducting layer in the width direction of the superconducting tape, and reduce the conduction cross-sectional area on the current path to further increase the resistance of the superconducting constant current switch when it is turned on; it can also be arranged by setting grooves in the superconducting layer to isolate the superconducting path from the non-superconducting path part, and by setting the track length and width of the superconducting path to further increase the resistance of the superconducting constant current switch when it is turned on, and it can also combine material reduction and setting grooves, so that the current can only enter another adjacent conductive layer from one conductive layer through the superconducting path, so that the entire superconducting constant current switch will present a larger resistance; and in terms of process, physical isolation (similar to grooves) is easier to form a relatively complex superconducting path than material reduction.

[0027] 4. The present invention increases the path length of the superconducting path and the length of the current path, so as to further increase the resistance when the superconducting constant current switch is turned on.

[0028] 5. The present invention uses laser technology to make groove lines to form a superconducting path between two adjacent conductive layers, and partially isolates the two conductive layers without the superconducting path, which helps to improve the accuracy of making the superconducting path, helps to improve the convenience of making a high-resistance superconducting constant current switch, and can further increase the resistance value of its disconnection resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0030] Figure 1 The present invention mainly embodies the schematic diagram of the structure of the second-generation superconducting tape in the background technology;

[0031] Figure 2 The present invention mainly embodies the working principle diagram of the superconducting switch in the background technology;

[0032] Figure 3 This is a schematic diagram of the axial structure of removing the unnecessary conductive layer of the superconducting layer away from the buffer layer in the first embodiment of the present invention;

[0033] Figure 4 It is a schematic diagram of a top view structure of removing the unnecessary conductive layer of the superconducting layer away from the buffer layer in the first embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the axial structure of the present invention mainly embodying the first embodiment in which the conductive layer on the side of the superconducting tape and the conductive layer on the part of the superconducting layer away from the buffer surface are removed;

[0035] Figure 6It is a schematic diagram of a top view of the structure of the present invention mainly embodying the first embodiment in which the conductive layer on the side of the superconducting tape and the conductive layer on the part of the superconducting layer away from the buffer surface are removed;

[0036] Figure 7 This is a schematic diagram of the axial structure of removing the peripheral material of the superconducting layer covering area in the first embodiment of the present invention;

[0037] Figure 8 This is a schematic diagram of a top view of the structure of removing the material around the superconducting layer cover area in the first embodiment of the present invention;

[0038] Fig. 9 This is a schematic diagram of the axial structure of the first embodiment of the present invention, in which the superconducting layer subtraction area is removed;

[0039] Fig.10 This is a schematic diagram of a top view of the structure of the first embodiment of the present invention, in which the superconducting layer subtraction area is removed;

[0040] Fig.11 This is a schematic diagram of the axial structure of removing unnecessary parts of the superconducting layer in the width direction in the first embodiment of the present invention;

[0041] Fig.12 This is a schematic diagram of a top view structure of removing unnecessary portions of the superconducting layer in the width direction in the first embodiment of the present invention;

[0042] Fig.13 It is a schematic diagram of the axial structure of the undulation portion formed in the exposed area of ​​the superconducting layer in the main embodiment of the present invention;

[0043] Fig.14 It is a schematic diagram of a top view of the structure of the undulation portion formed in the exposed area of ​​the superconducting layer in the main embodiment of the present invention;

[0044] Fig.15 This is a schematic diagram of using groove lines in the superconducting layer to physically isolate the conductive layer to form a straight superconducting path in the first embodiment of the present invention;

[0045] Fig.16 This is a schematic diagram of a bent superconducting path formed by using a groove line in the first embodiment of the present invention;

[0046] Fig.17 This is a schematic diagram of the depth of the groove line in the first embodiment of the present invention;

[0047] Fig.18 It is a schematic axial view of a structure that mainly embodies the present invention, which uses groove lines and subtractive materials to form a superconducting path;

[0048] Fig.19 It is a top view of a structure that mainly embodies the present invention, which uses groove lines and subtractive materials to form a superconducting path;

[0049] Fig. 20 The present invention mainly embodies the resistance and temperature relationship curve of the high-resistance superconducting constant current switch in the embodiment;

[0050] Fig.21 This is a schematic diagram of the axial structure of the present invention, which mainly embodies the use of groove lines to isolate the two sides of the superconducting layer width;

[0051] Fig. 22 This is a top view showing that the present invention mainly embodies the use of groove lines to isolate the two sides of the superconducting layer width;

[0052] Fig.23 It is an axial schematic diagram of the main embodiment of the present invention in which the superconducting layer on both sides of the width of the conductive layer is reduced;

[0053] Fig.24 It is a top view showing the main embodiment of the present invention in which the superconducting layer on both sides of the width of the conductive layer is reduced;

[0054] Fig.25 The present invention mainly embodies the axial structural schematic diagram of forming a superconducting path between two conductive layers by using a groove line;

[0055] Fig.26 The present invention mainly embodies a top view of forming a superconducting path between two conductive layers by using a groove line;

[0056] Fig. 27 The present invention mainly embodies the axial structural schematic diagram of forming a superconducting path between two conductive layers by material reduction;

[0057] Fig.28 This is a top view of the main embodiment of the present invention, which forms a superconducting path between two conductive layers by material reduction.

[0058] As shown in the figure: 1. Base layer; 2. Buffer layer; 3. Superconducting layer; 4. Silver covering layer; 5. Copper stabilization layer; 6. Conductive layer; 7. Groove line; 8. Superconducting path. DETAILED DESCRIPTION

[0059] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0060] It should be noted that the length direction of the present application refers to the direction of the strip, and the width direction of the present application refers to the width direction of the strip. Figure 1-Figure 28 The dotted lines in the figures all represent the groove lines 7.

[0061] Embodiment 1

[0062] like Figure 3 , Figure 4 , Figure 5 as well as Figure 6 As shown, a superconducting tape structure and a manufacturing method for improving the resistance of a superconducting constant current switch provided by the present invention include a conductive layer 6, a superconducting layer 3, a buffer layer 2 and a base layer 1, wherein the base layer 1, the buffer layer 2 and the superconducting layer 3 are stacked in sequence. The surface of the superconducting layer 3 away from the buffer layer 2 includes at least two conductive layers 6 arranged at intervals along the direction of the tape, and a superconducting path 8 for connecting the two conductive layers 6 is provided on the superconducting layer 3.

[0063] Since the buffer layer 2 in the second-generation superconducting tape is basically insulated, the superconducting tape structure of the present application can ensure that most of the current flows on the superconducting layer 3 side of the superconducting tape compared to the prior art. When the shunt current during excitation flows through the superconducting layer 3 side of the superconducting tape, the current will flow through the gap between the two conductive layers 6 located on the side of the superconducting layer 3 away from the buffer layer 2. Since the buffer layer 2 below the superconducting layer 3 is basically insulated, and the superconducting layer 3 will present a large resistance in the non-superconducting state, the entire superconducting constant current switch will present a large resistance.

[0064] The superconducting path 8 of the present application is turned on when the temperature is below the critical temperature, and is in a high resistance state when the temperature is above the critical temperature. The current is transmitted along the direction of the strip, and the current flows from one conductive layer 6 to another conductive layer 6 along the direction of the superconducting path 8, which ensures the stability of the switch operation, and the path length of the superconducting path 8 can be set according to actual needs to obtain the required resistance value when the superconducting constant current switch is turned on.

[0065] Specifically, the conductive layer 6 of the present application includes a silver covering layer 4 and / or a copper stabilizing layer 5. The superconducting tape structure of the present application can select the silver covering layer 4 as the conductive layer 6, can also select the copper stabilizing layer 5 as the conductive layer 6, and can also select the silver covering layer 4 and the copper stabilizing layer 5 to form the conductive layer 6. The present application preferably includes a silver covering layer 4 and a copper stabilizing layer 5.

[0066] Furthermore, the present application is explained by taking the conductive layer 6 as a silver covering layer 4 and a copper stabilization layer 5, and two conductive layers 6 arranged at intervals are arranged on the surface of the superconducting layer 3 facing away from the buffer layer 2 along the length direction of the superconducting tape as an example: the silver covering layer 4 covers the surface of the superconducting layer 3 facing away from the buffer layer 2, and the copper stabilization layer 5 covers the surface of the silver covering layer 4 facing away from the superconducting layer 3.

[0067] It should be noted that the superconducting layer 3 of the present application can be completely located on the side of the buffer layer 2 facing away from the base layer 1, and can also partially or completely wrap the side of the buffer layer 2 and / or the base layer 1. If the superconducting layer 3 wraps the buffer layer 2 and / or partially or completely wraps the side of the base layer 1, the superconducting layer 3 wrapping the side of the buffer layer 2 and / or the base layer 1 can be removed or destroyed by mechanical or chemical means. The unnecessary superconducting layer 3 can also be physically isolated from both the superconducting path 8 and the conductive layer 6.

[0068] like Figure 7 , Figure 8 , Fig. 9 as well as Fig.10 As shown, more specifically, the area of ​​the conductive layer 6 is less than or equal to the area of ​​the superconducting layer 3, the area of ​​the superconducting layer 3 is less than or equal to the area of ​​the buffer layer 2, and the area of ​​the buffer layer 2 is less than or equal to the area of ​​the substrate layer 1. The superconducting layer 3 can be reduced in both side regions in the length direction and / or in the width direction, so that the area of ​​the superconducting layer 3 is less than or equal to the area of ​​the buffer layer 2, and the resistance of the superconducting constant current switch when it is turned on is further increased while ensuring the superconducting constant current switch function.

[0069] The superconducting path 8 extends from one conductive layer 6 to another conductive layer 6, and can electrically connect two adjacent conductive layers 6. The resistance of the superconducting constant current switch when it is turned on can be further increased by reducing the conductive cross-sectional area of ​​the superconducting path 8 and increasing the path length of the superconducting path 8. The superconducting path 8 includes continuous regular straight line segments, connected regular arc segments and / or irregular shape segments. In actual production, a superconducting path 8 of a specific shape that meets actual design requirements can be formed by combining regular straight line segments, connected regular arc segments and / or irregular shape segments. Therefore, all improvements made to the path and shape of the superconducting path 8 fall within the scope of protection of this application.

[0070] It should be noted that the subtractive treatment of the superconducting layer 3 can be to remove the superconducting material at the corresponding position, or to destroy the superconducting properties of the superconducting material in the corresponding area. The material in the superconducting layer 3 that has lost its superconducting properties is no longer regarded as part of the superconducting layer 3, so as to further increase the resistance when the superconducting constant current switch is turned on.

[0071] It should be noted that the present application does not specifically limit the number of conductive layers 6 arranged on the superconducting layer 3 along the direction of the tape, nor the spacing between two adjacent conductive layers 6. Any number of conductive layers 6 can be inserted between two adjacent conductive layers 6 described in the application, and any improvement on the number of conductive layers 6 or the spacing between them falls within the protection scope of the present application.

[0072] like Figure 7 , Figure 8 , Fig. 9 , Fig.10 , Fig.11 as well as Fig.12 As shown, for ease of understanding, the present application provides a specific implementation method of forming a superconducting path 8 by reducing material:

[0073] The superconducting layer 3 is provided with material reduction zones on both sides along the length direction and / or the width direction of the strip, and the superconducting path 8 is formed entirely or partially by material reduction in the superconducting layer 3. The material on both sides in the length direction of the superconducting layer 3 can be removed or destroyed to form preliminary material reduction on both sides in the length direction of the superconducting layer 3, and the material on both sides in the width direction of the superconducting layer 3 can also be removed or destroyed. Furthermore, the material on both sides in the width direction of the superconducting layer 3 between two adjacent conductive layers 6 is removed or destroyed, so that the width of the superconducting layer 3 between the two conductive layers 6 is the same as the width of the conductive layer 6, and finally the width of the superconducting layer 3 as a whole is the same as the width of the conductive layer 6. The material on both sides in the width direction of the superconducting layer 3 between two adjacent conductive layers 6 is further reduced or destroyed, so that the width of the superconducting layer 3 between two adjacent conductive layers 6 is smaller than the width of the conductive layer 6. By reducing the conduction cross-sectional area of ​​the superconducting path 8, the resistance when the superconducting constant current switch is turned on is further increased. As Fig.13 and Fig.14 As shown, preferably, the superconducting path 8 can extend from one conductive layer 6 first in a first direction and then in a second direction, and the first direction and the second direction are not parallel, thereby increasing the path length of the superconducting path 8 to further increase the resistance when the superconducting constant current switch is turned on.

[0074] like Fig.15 , Fig.16 as well as Fig.17 As shown, for ease of understanding, the present application provides a specific implementation method of forming a superconducting path 8 by physical isolation:

[0075] The superconducting layer 3 is provided with groove lines 7, the depth of which is greater than or equal to the thickness of the superconducting layer 3, and the superconducting path 8 is formed by the groove lines 7 which are fully or partially surrounded. The groove lines 7 can isolate the two conductive layers 6 which are arranged at adjacent intervals except for the part of the superconducting path 8. Since the groove lines 7 can be made by laser ablation, the operation is convenient and the precision is high. At least two groove lines 7 are arranged between two adjacent conductive layers 6 to form a superconducting path 8 connecting the two adjacent conductive layers 6. The groove lines 7 are also arranged around the circumference of the two conductive layers 6 respectively. The groove lines 7 arranged around the circumference of the conductive layer 6 intersect with the groove lines 7 forming the superconducting path 8 or extend into the superconducting path 8, so as to ensure that the two adjacent conductive layers 6 are electrically connected only through the superconducting path 8. Therefore, it should be emphasized that any setting of the direction and shape of the groove lines 7, as long as it satisfies the requirement of electrically connecting the two adjacent conductive layers 6 and falls within the protection scope of this application.

[0076] like Fig.18 and Fig.19 As shown, for ease of understanding, the present application provides a specific implementation method of forming a superconducting path 8 by using subtraction and physical isolation: the material on both sides of the length direction of the superconducting layer 3 can be removed or destroyed, and preliminary subtraction is formed on both sides of the length direction of the superconducting layer 3. The material on both sides of the width direction of the superconducting layer 3 can also be removed or destroyed. The superconducting path 8 electrically connecting two adjacent conductive layers 6 can also be formed by processing groove lines 7 in the superconducting layer 3. The groove lines 7 are further processed in the superconducting layer 3 to ensure that the two adjacent conductive layers 6 are only electrically connected through the superconducting path 8. In terms of technology, physical isolation is easier to form a relatively complex superconducting path 8 than subtraction.

[0077] It should be further explained that the superconducting tape structure of the present application can be directly processed, or it can be made on the basis of the second-generation superconducting tape in the prior art. The superconducting tape structure of the present application can make the conductive layer 6 cover the surface of the base layer 1 away from the buffer layer 2. It is only necessary to ensure that the conductive layer 6 located on the surface of the base layer 1 away from the buffer layer 2 is not connected to the conductive layer 6 located on the surface of the superconducting layer 3 away from the buffer layer 2. At this time, the silver covering layer 4 can be selected as the conductive layer 6, and the copper stabilizing layer 5 can be selected as the conductive layer 6. The silver covering layer 4 and the copper stabilizing layer 5 can also be selected to form the conductive layer 6. Specifically, the silver covering layer 4 covers the surface of the base layer 1 away from the buffer layer 2, and the copper stabilizing layer 5 covers the surface of the silver covering layer 4 away from the base layer 1. The structure of the superconducting tape can also be selected to be a structure without a conductive layer 6 covering the surface of the base layer 1 away from the buffer layer 2.

[0078] like Fig. 20 The figure shows the relationship between resistance and temperature of the high-resistance superconducting constant current switch. The experiment was repeated five times. The superconducting tape structure of the present application and the conventional second-generation superconducting tape in the prior art were used for testing.

[0079] Test data such as Fig. 20 As shown, the resistance of the high-resistance superconducting constant current switch using the superconducting tape structure of the present application in the open state (temperature is 110K) is about 976mΩ, and the resistance of the superconducting constant current switch made of the conventional second-generation superconducting tape in the same prior art in the open state is only about 1mΩ. Compared with the conventional second-generation superconducting tape in the prior art, the resistance of the superconducting constant current switch made of the superconducting tape of the present application in the open state is increased by nearly 1000 times.

[0080] The present invention also provides a method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch, the manufacturing method comprising the following steps:

[0081] Step S1, prepare a superconducting tape for standby use.

[0082] Step S2: removing unnecessary conductive layer 6.

[0083] Step S3: destroy or remove unnecessary superconducting layers 3, and form a superconducting path 8 between two adjacent conductive layers 6.

[0084] It should be noted that the method of removing the unnecessary conductive layer 6 or superconducting layer 3 includes chemical etching and / or mechanical processing. The mechanical processing method includes polishing. The chemical etching method includes: using ferric chloride powder and anhydrous ethanol solution in a ratio of 1g:10ml to prepare a ferric chloride ethanol solution to corrode the copper stabilizing layer 5. Using a mixed solution prepared by ammonia water and hydrogen peroxide solution in a volume fraction ratio of 1:2 to corrode the silver covering layer 4. Among them, the concentration of ammonia water is 25%, and the concentration of hydrogen peroxide solution is 30%.

[0085] The superconducting layer 3 is corroded by an acidic solution. Specifically, the acidic solution is used to corrode the superconducting layer 3 in three stages according to different time periods: the first stage is to destroy the superconducting properties of the superconducting material, at which time the superconducting properties of the superconducting material are destroyed. The second stage is to remove the superconducting layer 3 material, at which time the superconducting layer 3 material is removed. The third stage is to remove part of the buffer layer 2 material. It should be emphasized that the above three stages of processing the superconducting layer 3 can solve the technical problems of the present application and achieve the purpose of the invention of the present application, so the above three stages are within the protection scope of the present application.

[0086] More specifically, on the basis of the second-generation superconducting tape, the silver covering layer 4 and / or the copper stabilizing layer 5 on the superconducting layer 3 may be partially removed first. Some superconducting tapes may be wrapped with a superconducting layer 3 on the side during the actual production and preparation process. In order to prevent the superconducting surface and the non-superconducting surface current from being turned on through the superconducting layer 3 wrapped on the side below the superconducting critical temperature, after removing the silver covering layer 4 and the copper stabilizing layer 5 on the superconducting layer 3, preferably, the silver covering layer 4 and / or the copper stabilizing layer 5 on the side of the superconducting tape are removed at the same time. Then, the superconducting layer 3 in the material reduction area of ​​the superconducting tape is destroyed or removed to increase the resistance when the superconducting constant current switch is turned on. Preferably, the superconducting layer 3 in the middle of the superconducting tape can be further destroyed or removed in the width direction, and the resistance when the superconducting constant current switch is turned on can be further increased by reducing the conduction cross-sectional area on the current path. It is also preferred that the superconducting layer 3 in the middle of the tape is further destroyed or removed, and the resistance when the superconducting constant current switch is turned on can be further increased by reducing the cross-sectional area while increasing the flow path length.

[0087] In another feasible implementation, for step S3 , laser ablation may be used to form groove lines 7 on the superconducting layer 3 , and a superconducting path 8 may be formed between two adjacent conductive layers 6 .

[0088] In another feasible implementation manner, with respect to step S3 , it is also possible to destroy or remove an unnecessary portion of the superconducting layer 3 , and to form a superconducting path 8 by laser processing a groove line 7 on the superconducting layer 3 .

[0089] Preferred Example 1

[0090] Based on the first embodiment, the present invention also provides a method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch. First, a superconducting tape is prepared:

[0091] (1) Ferric chloride powder and anhydrous ethanol solution are prepared in a ratio of 1 g:10 ml to prepare a ferric chloride ethanol solution to remove the unnecessary copper layer.

[0092] (2) A mixed solution of ammonia water and hydrogen peroxide solution in a volume fraction ratio of 1:2 is used, and the strip in step (1) is placed in the mixed solution to remove the unnecessary silver layer. The concentration of the ammonia water is 25%, and the concentration of the hydrogen peroxide solution is 30%.

[0093] (3) The tape treated in step (2) is placed in an acetic acid solution to react so as to destroy / remove the superconducting layer 33 in the reduced area of ​​the superconducting tape and the superconducting layer 3 that may be wrapped around the side of the superconducting tape.

[0094] Preferred Example 2

[0095] Based on the first embodiment, the present invention also provides a method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch. First, a superconducting tape is prepared:

[0096] (1) Ferric chloride powder and anhydrous ethanol solution are prepared in a ratio of 1 g:10 ml to prepare a ferric chloride ethanol solution to remove the unnecessary copper layer.

[0097] (2) A mixed solution of ammonia water and hydrogen peroxide solution in a volume fraction ratio of 1:2 is used, and the strip in step (1) is placed in the mixed solution to remove the unnecessary silver layer. The concentration of the ammonia water is 25%, and the concentration of the hydrogen peroxide solution is 30%.

[0098] (3) The two side surfaces in the length direction of the strip processed in step (2) are polished by a grinder to remove the superconducting layer 3 that may be wrapped around the side surface of the superconducting strip, and the connection between the superconducting layer 3 and the Hastelloy layer on the side surface of the superconducting strip is cut off; for the two side surfaces in the width direction, an acidic solution is used to destroy / remove the superconducting layer 3 that may be wrapped around the side surface of the superconducting strip.

[0099] Preferred Example 3

[0100] Based on the first embodiment, the present invention also provides a method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch. First, a superconducting tape is prepared:

[0101] (1) The two side surfaces of the tape in the longitudinal direction are polished with a polishing machine to remove the copper layer, silver layer and superconducting layer 3 on the side surfaces of the superconducting tape.

[0102] (2) Ferric chloride powder and anhydrous ethanol solution are prepared in a ratio of 1 g:10 ml to form a ferric chloride ethanol solution to remove the unnecessary copper layer.

[0103] (3) A mixed solution of ammonia water and hydrogen peroxide solution in a volume fraction ratio of 1:2 is used, and the strip in step (1) is placed in the mixed solution to remove the unnecessary silver layer. The concentration of ammonia water is 25%, and the concentration of hydrogen peroxide solution is 30%.

[0104] Preferred Example 4

[0105] like Fig.15 and Fig.16 As shown, based on Example 1, the present invention provides a superconducting tape structure for a superconducting constant current switch, wherein a groove line 7 is formed on the superconducting layer 3 to form a superconducting path 8 that connects two adjacent conductive layers 6, and the groove line 7 partially isolates the two adjacent conductive layers 6 except for the superconducting path 8. This specific embodiment provides a feasible technical solution.

[0106] In the top view of the superconducting tape, a superconducting path 8 is formed between two conductive layers 6 in an isolated state through a groove line 7 , and the superconducting path 8 extends from one conductive layer 6 to the other conductive layer 6 .

[0107] This specific embodiment provides a feasible extension scheme of the superconducting path 8: one end of the superconducting path 8 directly extends from one of the conductive layers 6 to the other conductive layer 6 along the length direction of the superconducting tape.

[0108] This specific embodiment provides another feasible extension scheme of the superconducting path 8: one end of the superconducting path 8 extends from one of the conductive layers 6 along the length direction of the superconducting tape for a certain length, then turns and extends along the width direction of the superconducting tape for a certain length, and then turns and extends along the length direction of the superconducting tape for a certain length until it extends to another conductive layer 6. It should be noted that the number of turns and the turning angle of the extension of the superconducting path 8 can be designed according to actual conditions.

[0109] The groove lines 7 are also arranged on the outer periphery of the two conductive layers 6 to isolate the two conductive layers 6 except for the superconducting path 8. Specifically, the groove lines 7 form a rectangular frame in the top view of the superconducting tape, and the rectangular frame surrounds the two conductive layers 6. The superconducting path 8 extends a groove line 7 perpendicular to the groove lines 7 on both sides of the extension direction.

[0110] A groove line 7 extending from the upper side of the superconducting path 8 among the groove lines 7 is connected to the upper side of the rectangular frame, and a groove line 7 extending from the lower side of the superconducting path 8 is connected to the lower side of the rectangular frame, thereby realizing partial isolation of two adjacent conductive layers 6 except for the superconducting path 8.

[0111] It should be noted that the two groove lines 7 extending from the superconducting path 8 may also extend into the superconducting path 8, so that the superconducting path 8 is conductive when the temperature is below the critical temperature, and is in a high resistance state when the temperature is above the critical temperature.

[0112] Preferred Example 5

[0113] like Fig.18 , Fig.19 , Fig.21 , Fig. 22 , Fig.23 , Fig.24 , Fig.25 , Fig.26 , Fig. 27 as well as Fig.28 As shown, based on Example 1, a superconducting tape structure for a superconducting constant current switch provided by the present invention can first reduce the material on both sides of the length direction of the superconducting layer 3 by chemical or physical means, and then use laser processing to make groove lines 7 on both sides of the width of the superconducting layer 3.

[0114] It should be noted that the technical solution of the present application utilizes material reduction followed by laser processing of the groove lines 7 to form the superconducting path 8 , and ensures that the current can only be transmitted between the two conductive layers 6 through the superconducting path 8 .

[0115] like Fig.18 and 19 As shown, part of the superconducting layer 3 material is retained on both sides of the width of the two conductive layers 6, and a groove line 7 parallel to the length direction of the tape is set on both sides of the width of the two conductive layers 6 for physical isolation. The current can only be transmitted between the two conductive layers 6 through the superconducting path 8.

[0116] like Fig.21 and Fig. 22 As shown, a groove line 7 parallel to the length direction of the strip is provided on both sides of the width of the two conductive layers 6 for physical isolation, so as to ensure that the current flows within the surface of the superconducting layer 3 where the conductive layer 6 is located.

[0117] like Fig.23 and Fig.24As shown, the superconducting layers 3 on both sides of the width direction of the two conductive layers 6 are partially reduced to ensure that the superconducting layer 3 material retained on both sides of the width direction of the conductive layer 6 is integrated with the superconducting layer 3 material located between the two conductive layers 6. A groove line 7 parallel to the length direction of the strip is provided on both sides of the width of the two conductive layers 6 for physical isolation. The current can only be transmitted between the two conductive layers 6 through the superconducting path 8.

[0118] like Fig.25 and Fig.26 As shown, in Fig.23 and Fig.24 On the basis of the above, the laser is used to process the groove line 7 in the superconducting layer 3, so that the path length of the superconducting path 8 connecting the two conductive layers 6 is increased and the path width is reduced. The method of processing the groove line 7 by laser is easier to form a relatively complex superconducting path 8 than the subtractive method. Among them, the conductive layer 6 may include a silver covering layer 4 and / or a copper stabilizing layer 5.

[0119] like Fig. 27 and 28 As shown, the superconducting layer 3 materials on both sides of the width of the two conductive layers 6 can be completely reduced, and the superconducting layer 3 materials located between the two conductive layers 6 can be partially reduced, and then a groove line 7 parallel to the length direction of the tape is set on both sides of the width of the superconducting layer 3 for physical isolation, so that the current can only be transmitted between the two conductive layers 6 through the superconducting path 8.

[0120] It should be noted that the present application does not specifically limit the shape of the superconducting path 8 formed by material reduction and laser processing of the groove line 7, and all improvements on the shape of the superconducting path 8 fall within the protection scope of the present application.

[0121] Change Example 1

[0122] Based on the first embodiment, in a superconducting tape structure for a superconducting constant current switch provided by the present invention, the surface of the base layer 1 facing away from the buffer layer 2 may or may not be provided with a conductive layer 6 .

[0123] The conductive layer 6 may be a copper stabilization layer 5 , and the conductive layer 6 located on the surface of the substrate layer 1 facing away from the buffer layer 2 may be the copper stabilization layer 5 covering the surface of the substrate layer 1 facing away from the buffer layer 2 .

[0124] The conductive layer 6 may also be a silver covering layer 4 , and the conductive layer 6 located on the side of the substrate 1 facing away from the buffer layer 2 may be a silver covering layer 4 covering the side of the substrate 1 facing away from the buffer layer 2 .

[0125] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0126] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A superconducting tape structure for improving the resistance of a superconducting constant current switch, characterized in that: It comprises a conductive layer (6), a superconducting layer (3), a buffer layer (2) and a base layer (1), wherein the base layer (1), the buffer layer (2) and the superconducting layer (3) are stacked in sequence; The surface of the superconducting layer (3) facing away from the buffer layer (2) comprises at least two conductive layers (6) arranged at intervals along the direction of the strip, and a superconducting path (8) for connecting the two conductive layers (6) is arranged on the superconducting layer (3).

2. The superconducting tape structure for improving the resistance of a superconducting constant current switch according to claim 1, characterized in that: The superconducting path (8) extends from one conductive layer (6) to another conductive layer (6); The superconducting path (8) comprises continuous regular straight line segments, connected regular arc segments and / or irregular shape segments.

3. The superconducting tape structure for improving the resistance of a superconducting constant current switch according to claim 1, characterized in that: The superconducting path (8) is formed by material reduction in the superconducting layer (3), and / or is formed by physical isolation in the superconducting layer (3), and the current is transmitted along the direction of the strip, and the current flows from one of the conductive layers (6) along the direction of the superconducting path (8) into another conductive layer (6).

4. The superconducting tape structure for improving the resistance of a superconducting constant current switch according to claim 3, characterized in that: The superconducting layer (3) is provided with a groove line (7), and the depth of the groove line (7) is greater than or equal to the thickness of the superconducting layer (3); The superconducting path (8) is formed by being completely or partially surrounded by the groove line (7).

5. The superconducting tape structure for improving the resistance of a superconducting constant current switch according to claim 3, characterized in that: The superconducting layer (3) is provided with reduced material areas on both sides along the length direction of the strip and / or on both sides along the width direction; The superconducting path (8) is formed entirely or partially by reducing the material of the superconducting layer (3).

6. The superconducting tape structure for improving the resistance of a superconducting constant current switch according to claim 1, characterized in that: The conductive layer (6) comprises a silver covering layer (4) and / or a copper stabilizing layer (5); The area of ​​the conductive layer (6) is smaller than or equal to the area of ​​the superconducting layer (3).

7. The superconducting tape structure for improving the resistance of a superconducting constant current switch according to claim 1, characterized in that: The conductive layer (6) covers the surface of the substrate layer (1) facing away from the buffer layer (2).

8. A method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch, characterized in that: A method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch according to any one of claims 1 to 7 comprises the following steps: Step S1, prepare a superconducting tape for standby use; Step S2, removing unnecessary conductive layer (6); Step S3: destroy or remove unnecessary superconducting layers (3), and form a superconducting path (8) between two adjacent conductive layers (6).

9. A method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch as claimed in claim 8, characterized in that: The method for removing the unnecessary conductive layer (6) or superconducting layer (3) in step S3 includes chemical etching and / or mechanical processing.

10. A method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch as claimed in claim 9, characterized in that: When the side of the tape is coated with a superconducting layer (3), after removing the silver covering layer (4) and / or the copper stabilizing layer (5) on the superconducting layer (3), the silver covering layer (4) and / or the copper stabilizing layer (5) on the side of the superconducting tape are removed at the same time, and then the superconducting layer (3) to be reduced is destroyed or removed.

11. A method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch as claimed in claim 8, characterized in that: With respect to step S3, a groove line (7) may be processed on the superconducting layer (3), and a superconducting path (8) may be formed between two adjacent conductive layers (6).

12. A method for manufacturing a superconducting tape structure for improving the resistance of a superconducting constant current switch as claimed in claim 8, characterized in that: With respect to step S3, it is also possible to destroy or remove unnecessary superconducting layers (3), and process groove lines (7) on the superconducting layers (3) to form superconducting paths (8).

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