Superconductor joining device and joining method

Abstract

The present invention relates to a joining apparatus and joining method for superconductors, wherein the joining apparatus for superconductors includes a chamber section, a heating section attached to the chamber section for supporting and heating a first wire section and a second wire section, a pressurizing section attached to the chamber section for pressurizing the first wire section and the second wire section, and an adjusting section for adjusting the internal air pressure of the chamber section, and the joining method for superconductors includes a setting step for overlapping the ends of the first wire section and the second wire section inside the chamber section, a vacuum step for maintaining the inside of the chamber section in a vacuum state, a joining step for joining the first wire section and the second wire section, and a heat treatment step for heat treating the first wire section and the second wire section.

Description

[Technical Field]

[0001] The present invention relates to a joining apparatus and a joining method for superconductors, and more particularly to a joining apparatus and a joining method for superconductors that joins superconducting wires in a single chamber, thereby quickly performing the work process and preventing joining defects. [Background technology]

[0002] Generally, superconductivity refers to the phenomenon in which electrical resistance disappears in a material under certain conditions, and the temperature at which superconductivity occurs varies depending on the type of metal or compound.

[0003] Superconductors are classified into low-temperature superconductors (liquid helium temperature) and high-temperature superconductors (liquid nitrogen temperature) based on their low critical temperature. High-temperature superconductors (HTS) consist of a substrate, an intermediate layer (buffer layer), a superconducting layer, and a protective layer. The substrate is a metal body, and the buffer layer can consist of 2 to 5 layers depending on the properties.

[0004] Superconductors, which are used to improve energy efficiency, are materials and products that exhibit the phenomenon of superconductivity, where electrical resistance becomes zero below the critical temperature (Tc) and current continues to flow without loss.

[0005] It is known that if the crystal orientation at the grain boundary is not aligned, the critical current drops significantly, so in order to increase the critical current of YBCO-based second-generation high-temperature superconducting wire, it is necessary to align the crystal orientation of adjacent crystal grains.

[0006] To align the orientation of the crystal grains in a superconducting thin film, it is necessary to prepare an in-plane oriented intermediate layer by evaporation and then grow the superconducting layer epitaxially. For in-plane orientation, two substrate materials are used to achieve biaxial orientation. One is a process to create a metal tape with biaxially oriented crystal grains by forming a recrystallized texture through rolling and vacuum heat treatment. The other is to use a polycrystalline non-oriented substrate and develop a conductor with high current density (Jc) characteristics.

[0007] Meanwhile, the thickness of the superconducting wire is 60 to 90 μm, and several layers are laminated. Conventionally, to connect the superconducting wires, a pressurizing process is performed in a first chamber, and a heating process is performed in a second chamber.

[0008] However, this joining method requires the use of at least two chambers, which increases the size of the processing equipment, and there is a problem that product defects may occur during the process of moving the superconducting wires that have been primarily joined in the first chamber to the second chamber. Therefore, there is a need to improve this.

[0009] The background art of the present invention is disclosed in Korean Patent Publication No. 10-0760993 (registered on September 17, 2007, title of invention: Apparatus and method for lamination joining of superconducting wire). Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been devised to solve the above-mentioned problems, and its object is to provide a joining apparatus and method for superconductors that can join superconducting wires in a single chamber, thereby speeding up the process and preventing joining defects. [Means for solving the problem]

[0011] The superconductor joining device of the present invention includes a chamber section, a heating section attached to the chamber section and supporting and heating a first wire section and a second wire section, a pressurizing section attached to the chamber section and pressurizing the first wire section and the second wire section, and an adjusting section for adjusting the internal air pressure of the chamber section.

[0012] The chamber portion may include a lower chamber portion and an upper chamber portion covering an upper portion of the lower chamber portion.

[0013] The heating section may include a heating support section attached to the chamber section and supporting the first wire section and the second wire section, and a heater section attached to the heating support section and heating the heating support section.

[0014] The pressure applying section may include a pressure applying cylinder section attached to the chamber section and having a variable length, and a pressure applying main body section formed on the pressure applying cylinder section, movable up and down, and applying pressure to the first wire section and the second wire section.

[0015] The adjusting unit may include an adjusting sensor that measures the internal pressure of the chamber, and an adjusting pump that receives a sensing signal from the adjusting sensor and discharges the air inside the chamber to the outside.

[0016] The superconductor joining device according to the present invention may further include a cooling unit that is attached to the chamber unit and cools the first wire unit and the second wire unit.

[0017] The cooling unit may include a cooling sensor that senses at least one of the temperature and pressure inside the chamber, and a cooling supply unit that receives a sensing signal from the cooling sensor and supplies a cooling gas into the chamber.

[0018] The cooling section can cool the first wire section and the second wire section that have been heated for the joining process, and can cool the first wire section and the second wire section that have been heat-treated at a temperature lower than that of the joining process to an initial temperature.

[0019] The wire assembly may further include a vibrating unit that applies ultrasonic vibration to the first wire portion and the second wire portion.

[0020] The superconductor joining device of the present invention may further include an auxiliary joining part that is arranged between the first wire part and the second wire part and is joined to the first wire part and the second wire part by the heating part and the pressure part.

[0021] The joining method for superconductors according to the present invention can include a setting step of overlapping the ends of a first wire portion and a second wire portion inside a chamber portion, a vacuum step of maintaining the inside of the chamber portion in a vacuum state, a joining step of joining the first wire portion and the second wire portion, and a heat treatment step of heat treating the first wire portion and the second wire portion.

[0022] The joining step can apply heat and pressure to the first wire part and the second wire part.

[0023] The joining step may include applying vibration to the first wire portion and the second wire portion.

[0024] The joining method for superconductors according to the present invention may further include a cooling step of cooling the inside of the chamber.

[0025] In the cooling step, a cooling unit may supply a cooling gas into the chamber in accordance with the temperature and pressure inside the chamber.

[0026] The cooling section can cool the first wire section and the second wire section that have been heated for the joining process, and can cool the first wire section and the second wire section that have been heat-treated at a temperature lower than that of the joining process to an initial temperature.

[0027] An auxiliary joint may be disposed between the first wire portion and the second wire portion. [Effects of the Invention]

[0028] In the superconductor joining device and joining method according to the present invention, the first wire part and the second wire part placed in one chamber can be joined together by being heated by the heating part and pressed by the pressing part. [Brief explanation of the drawings]

[0029] [Figure 1]1 is a diagram schematically illustrating a superconductor joining device according to an embodiment of the present invention.

[0030] [Figure 2] FIG. 2 is a diagram schematically illustrating a chamber unit according to an embodiment of the present invention.

[0031] [Figure 3] FIG. 2 is a diagram schematically illustrating a heating unit according to an embodiment of the present invention.

[0032] [Figure 4] FIG. 2 is a diagram schematically illustrating a pressure unit according to an embodiment of the present invention.

[0033] [Figure 5] 1 is a diagram illustrating an adjustment unit according to an embodiment of the present invention;

[0034] [Figure 6] FIG. 2 is a diagram illustrating a cooling unit according to an embodiment of the present invention.

[0035] [Figure 7] FIG. 2 is a diagram schematically illustrating a vibration section according to an embodiment of the present invention.

[0036] [Figure 8] 1 is a diagram illustrating a schematic diagram of an auxiliary joint according to an embodiment of the present invention.

[0037] [Figure 9] 1 is a flowchart illustrating a joining method for superconductors according to an embodiment of the present invention.

[0038] [Figure 10] 1 is a graph showing a schematic diagram of time versus temperature for a superconductor junction according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] Hereinafter, embodiments of a joining device and joining method for superconductors according to the present invention will be described with reference to the accompanying drawings. In this process, the thickness of wires and the size of components shown in the drawings may be exaggerated for clarity and convenience of explanation. Furthermore, the terms used below are defined in consideration of the functions of the present invention and may vary depending on the intentions or practices of users or operators. Therefore, the definitions of these terms should be based on the contents of this specification as a whole.

[0040] 1 is a diagram schematically illustrating a superconductor joining apparatus according to an embodiment of the present invention. Referring to FIG. 1, the superconductor joining apparatus 1 according to an embodiment of the present invention may include a chamber unit 10, a heating unit 20, a pressurizing unit 30, and an adjusting unit 40.

[0041] The chamber section 10 may be fixedly installed on the ground or a fixed object. For example, the chamber section 10 may be separated or attached to a pair, allowing the first wire section 100 and the second wire section 200 to pass through.

[0042] The heating unit 20 is mounted in the chamber unit 10 and can support and heat the first wire rod part 100 and the second wire rod part 200. For example, the heating unit 20 can be built into the chamber unit 10, and the ends of the first wire rod part 100 and the second wire rod part 200 can be seated on the heating unit 20 in an overlapping state. When the first wire rod part 100 and the second wire rod part 200 are seated on the heating unit 20, the heating unit 20 can heat the first wire rod part 100 and the second wire rod part 200 to a set temperature.

[0043] The pressurizing unit 30 is mounted in the chamber unit 10 and can pressurize the first wire rod unit 100 and the second wire rod unit 200. For example, the pressurizing unit 30 is disposed opposite the heating unit 20 and can pressurize the first wire rod unit 100 and the second wire rod unit 200 seated on the heating unit 20 at a set pressure while moving up and down.

[0044] The adjusting unit 40 can adjust the internal air pressure of the chamber unit 10. For example, the adjusting unit 40 can create a vacuum state inside the chamber unit 10. This can prevent defects from occurring during the joining process between the first wire part 100 and the second wire part 200.

[0045] 2 is a schematic diagram illustrating a chamber unit according to an embodiment of the present invention. Referring to FIG. 2, a chamber unit 10 according to an embodiment of the present invention may include a lower chamber unit 11 and an upper chamber unit 12.

[0046] The lower chamber part 11 may be fixedly installed on a fixed object such as the ground. For example, the lower chamber part 11 may include a lower chamber box part 111 having a box shape with an open top, and lower chamber extension parts 112 extending from the lower chamber box part 111 to both sides and enclosing the first wire part 100 and the second wire part 200, respectively.

[0047] The upper chamber part 12 may cover the upper part of the lower chamber part 11. For example, the upper chamber part 12 may include an upper chamber box part 121 having a box shape with an open bottom, and upper chamber extension parts 122 extending from the upper chamber box part 121 to both sides and enclosing the first wire part 100 and the second wire part 200, respectively.

[0048] The lower chamber box part 111 and the upper chamber box part 121 are in close contact with each other to maintain airtightness, and the lower chamber extension part 112 and the upper chamber extension part 122 are in close contact with each other to allow the first wire part 100 and the second wire part 200 to pass through. In this case, a seal member may be added between the lower chamber extension part 112 and the upper chamber extension part 122 and the first wire part 100 or the second wire part 200 to maintain airtightness.

[0049] 3 is a schematic diagram illustrating a heating unit 20 according to an embodiment of the present invention. Referring to FIG. 3, the heating unit 20 according to an embodiment of the present invention may include a heating support unit 21 and a heater unit 22.

[0050] The heating support 21 is attached to the chamber 10 and can support the first wire part 100 and the second wire part 200. For example, the heating support 21 can be installed inside the lower chamber 11. Ends of the first wire part 100 and the second wire part 200 can be placed on and overlap the upper surface of the heating support 21.

[0051] The heater unit 22 is attached to the heating support unit 21 and can heat the heating support unit 21. For example, the heater unit 22 may be built into the heating support unit 21 or may be attached to the side or bottom surface of the heating support unit 21. When power is applied to the heater unit 22, the heating support unit 21 is heated, and the heater unit 22 can heat the heating support unit 21 to a set temperature.

[0052] 4 is a diagram illustrating a pressure unit 30 according to an embodiment of the present invention. Referring to FIG. 4, the pressure unit 30 according to an embodiment of the present invention may include a pressure cylinder 31 and a pressure body 32.

[0053] The pressure cylinder 31 is attached to the chamber 10 and its length can be adjusted. For example, the pressure cylinder 31 can include a cylinder body 311 fixedly installed on the upper side of the upper chamber 12, and a cylinder adjustable part 312 extending downward from the cylinder body 311 and built into the upper chamber 12. The cylinder body 311 allows the vertical length of the cylinder adjustable part 312 to be adjusted or the cylinder adjustable part 312 to be moved up and down.

[0054] The pressure body 32 is formed on the pressure cylinder 31 and is movable up and down to apply pressure to the first wire part 100 and the second wire part 200. For example, the pressure body 32 is attached to the lower end of the adjustable cylinder part 312 and can be moved up and down by the adjustable cylinder part 312. The pressure body 32 can press and apply pressure to the first wire part 100 and the second wire part 200, whose ends overlap and are seated on the heating support part 21. Meanwhile, a heater part 22 is further attached to the pressure body 32, so that the first wire part 100 and the second wire part 200 can be heated in both upward and downward directions.

[0055] 5 is a diagram illustrating a regulator 40 according to an embodiment of the present invention. Referring to FIG. 5, the regulator 40 may include a regulator sensor 41 and a regulator pump 42.

[0056] The adjustment sensor 41 may measure the internal pressure of the chamber 10. For example, the adjustment sensor 41 may measure the internal pressure of the chamber 10 when the lower chamber 11 and the upper chamber 12 are in close contact with each other.

[0057] The adjustment pump unit 42 may receive a detection signal from the adjustment sensor 41 and discharge air from inside the chamber unit 10 to the outside. For example, the adjustment pump unit 42 may include a pump duct unit 421 connected to at least one of the upper chamber unit 11 and the lower chamber unit 12, and a pump driver 422 formed in the pump duct unit 421 and discharging air to the outside.

[0058] 6 is a diagram schematically illustrating a cooling unit according to an embodiment of the present invention. Referring to FIG. 6, the superconductor joining device 1 according to an embodiment of the present invention may further include a cooling unit 50.

[0059] The cooling unit 50 is mounted in the chamber unit 10 and can cool the first wire unit 100 and the second wire unit 200. For example, the cooling unit 50 may include a cooling sensor 51 that senses at least one of the temperature and pressure inside the chamber unit 10, and a cooling supply unit 52 that receives a sensing signal from the cooling sensor 51 and supplies a cooling gas into the chamber unit 10. The cooling supply unit 52 may supply nitrogen.

[0060] 7 is a diagram schematically illustrating a vibrating unit according to an embodiment of the present invention. Referring to FIG. 7, the joining device 1 for superconductors according to an embodiment of the present invention may further include a vibrating unit 60.

[0061] The vibrating unit 60 can provide ultrasonic vibrations to the first wire part 100 and the second wire part 200. As an example, the vibrating unit 60 can be provided in the pressing body 32, and when power is applied, can provide vibrations to the joint between the first wire part 100 and the second wire part 200. Alternatively, the vibrating unit 60 can be provided in the heating support 21.

[0062] 8 is a diagram schematically illustrating an auxiliary joint according to one embodiment of the present invention. Referring to FIG. 8, the superconductor joining device 1 according to one embodiment of the present invention may further include an auxiliary joint 70.

[0063] The auxiliary bonding portion 70 may be disposed between the first wire portion 100 and the second wire portion 200 and bonded to the first wire portion 100 and the second wire portion 200 by the heating portion 20 and the pressure portion 30. For example, an indium foil may be used as the auxiliary bonding portion 70. The auxiliary bonding portion 70 may be disposed where the first wire portion 100 and the second wire portion 200 overlap each other.

[0064] 9 is a flow chart showing a method for joining superconductors according to an embodiment of the present invention, and FIG. 10 is a graph showing a relationship between time and temperature for joining superconductors according to an embodiment of the present invention. The method for joining superconductors according to an embodiment of the present invention will be described below with reference to FIGS. 9 and 10.

[0065] In the setting step S10, the ends of the first wire rod part 100 and the second wire rod part 200 are overlapped inside the chamber part 10. For example, the chamber part 10 includes a lower chamber part 11 and an upper chamber part 12. After the upper chamber part 12 is raised, the ends of the first wire rod part 100 and the second wire rod part 200 can be overlapped and seated in the heating part 20 formed in the lower chamber part 11. When the ends of the first wire rod part 100 and the second wire rod part 200 are overlapped and seated in the heating part 20, the upper chamber part 12 is lowered to seal the inside of the chamber part 10. At this time, the pressurizing part 32 can be brought into close contact with the overlapping area of ​​the first wire rod part 100 and the second wire rod part 200 to fix the first wire rod part 100 and the second wire rod part 200. Alternatively, a separate holder can fix the first wire rod part 100 and the second wire rod part 200. On the other hand, the auxiliary joining portion 70 is arranged between the first wire portion 100 and the second wire portion 200 to temporarily join the first wire portion 100 and the second wire portion 200, and the joining strength between the first wire portion 100 and the second wire portion 200 can be increased by the heating portion 20 and the pressure applying portion 30.

[0066] The evacuation step S20 maintains a vacuum state inside the chamber unit 10. For example, when the control unit 40 exhausts the air inside the chamber unit 10 to the outside, the inside of the chamber unit 10 may be in a vacuum state.

[0067] The joining step S30 joins the first wire part 100 and the second wire part 200. As an example, the heating unit 20 may be driven to heat the first wire part 100 and the second wire part 200, and the pressure unit 30 may be driven to pressurize the first wire part 100 and the second wire part 200. Then, the vibration unit 60 may be selectively driven to vibrate the first wire part 100 and the second wire part 200.

[0068] The heat treatment step S40 heat treats the first wire part 100 and the second wire part 200. As an example, the heat treatment step can apply pressure and heat to the first wire part 100 and the second wire part 200 at a temperature lower than that in the joining step.

[0069] The cooling step S50 cools the chamber unit 10. For example, when the cooling unit 50 is driven, nitrogen gas is injected into the chamber unit 10 to cool the first wire rod part 100 and the second wire rod part 200.

[0070] Once the first wire part 100 and the second wire part 200 have cooled, the upper chamber part 12 can be raised and the first wire part 100 and the second wire part 200 can be removed from the chamber part 10 .

[0071] More specifically, when the joining step is performed, the heating unit 20 and the pressure unit 30 are driven for a first time t1, whereby the temperatures of the first wire part 100 and the second wire part 200 rise from a first temperature T1 to a fourth temperature T4.

[0072] When the first wire part 100 and the second wire part 200 reach the fourth temperature T4, the heating unit 20 and the pressure unit 30 are continuously driven until the second time t2, and the joining process is performed. At this time, the first wire part 100 and the second wire part 200 are maintained at the fourth temperature T4, and the pressure of the pressure unit 30 is also maintained at the set pressure. Then, the vibration unit 60 is driven to provide ultrasonic vibrations to the first wire part 100 and the second wire part 200.

[0073] After the second time t2 has elapsed, the driving of the heating unit 20 and the pressure unit 30 is stopped until the third time t3 is reached. Then, the driving of the vibration unit 60 is also stopped. At this time, the first wire part 100 and the second wire part 200 are cooled to the second temperature T2 by natural cooling or cooling via the cooling unit 50.

[0074] After the third time t3 has elapsed, the first wire part 100 and the second wire part 200 maintain the second temperature T2 until the fourth time t4 is reached.

[0075] After the fourth time t4 has elapsed, the heating unit 20 and the pressure unit 30 are driven until a fifth time t5 is reached, and the first wire part 100 and the second wire part 200 are heated to a third temperature T3.

[0076] When the first wire part 100 and the second wire part 200 reach the third temperature T3, the heating part 20 and the pressure part 30 are continuously driven to perform the heat treatment process until the sixth time t6. At this time, the first wire part 100 and the second wire part 200 are maintained at the third temperature T3, and the pressure of the pressure part 30 can also be maintained at the set pressure.

[0077] After the sixth time t6 has elapsed, the driving of the heating unit 20 and the pressing unit 30 is stopped until the seventh time t7 is reached. At this time, the first wire part 100 and the second wire part 200 are cooled by the cooling unit 50 to the first temperature T1, which is the initial temperature.

[0078] The cooling section 50 cools the first wire section 100 and the second wire section 200 that have been heated for the joining process, and can cool the first wire section 100 and the second wire section 200 that have been heat-treated at a temperature lower than that of the joining process to their initial temperature.

[0079] At this time, the second temperature T2 is higher than the first temperature T1, the third temperature T3 is higher than the second temperature T2, and the fourth temperature T4 is higher than the third temperature T3.

[0080] In the joining apparatus and joining method for superconductors according to one embodiment of the present invention, a first wire part 100 and a second wire part 200 placed in one chamber part 10 can be joined together by being heated by a heating part 20 and pressurized by a pressurizing part 30.

[0081] Although the present invention has been described with reference to the embodiments shown in the drawings, these are merely illustrative, and those skilled in the art will recognize that various modifications and equivalent embodiments are possible. Therefore, the true technical scope of the present invention should be determined by the following claims.

Claims

1. A chamber portion; a heating unit attached to the chamber unit to support and heat the first wire rod unit and the second wire rod unit; a pressurizing unit attached to the chamber unit and configured to pressurize the first wire rod portion and the second wire rod portion; and an adjusting unit for adjusting the internal air pressure of the chamber unit.

2. The chamber section includes: a lower chamber portion; 2. The superconductor joining device according to claim 1, further comprising: an upper chamber portion covering an upper portion of the lower chamber portion.

3. The heating unit is a heating support part attached to the chamber part and supporting the first wire part and the second wire part; 2. The joining device for superconductors according to claim 1, further comprising: a heater unit attached to said heating support unit for heating said heating support unit.

4. The pressure applying unit is a pressure cylinder portion attached to the chamber portion and having a variable length; 2. The joining device for superconductors according to claim 1, further comprising: a pressure body portion formed on the pressure cylinder portion, movable up and down, and applying pressure to the first wire portion and the second wire portion.

5. The adjustment unit is an adjustment sensor for measuring the internal pressure of the chamber; 2. The apparatus for joining superconductors according to claim 1, further comprising: an adjustment pump unit receiving a detection signal from the adjustment detection unit and discharging the air inside the chamber unit to the outside.

6. 2. The superconductor joining device according to claim 1, further comprising a cooling unit mounted in the chamber unit to cool the first wire unit and the second wire unit.

7. The cooling unit is a cooling sensor that senses at least one of the temperature and pressure inside the chamber; 7. The apparatus for joining superconductors according to claim 6, further comprising: a cooling supply unit for receiving a detection signal from the cooling detection unit and supplying a cooling gas into the chamber unit.

8. 8. The superconductor joining device according to claim 7, wherein the cooling unit cools the first wire portion and the second wire portion that have been heated for the joining process, and cools the first wire portion and the second wire portion that have been heat-treated at a temperature lower than that of the joining process to an initial temperature.

9. 2. The joining device for superconductors according to claim 1, further comprising a vibrating unit for applying ultrasonic vibration to the first wire portion and the second wire portion.

10. 2. The joining device for superconductors according to claim 1, further comprising an auxiliary joining part arranged between the first wire part and the second wire part and joined to the first wire part and the second wire part by the heating part and the pressure part.

11. a setting step of overlapping the ends of the first wire rod portion and the second wire rod portion inside the chamber portion; a vacuum step of maintaining the inside of the chamber in a vacuum state; a joining step of joining the first wire rod portion and the second wire rod portion; a heat treatment step of heat treating the first wire portion and the second wire portion.

12. 12. The joining method for superconductors according to claim 11, wherein the joining step heats and presses the first wire portion and the second wire portion.

13. 13. The joining method for superconductors according to claim 12, wherein the joining step includes a step of applying vibration to the first wire portion and the second wire portion.

14. The joining method for superconductors according to claim 11, further comprising a cooling step of cooling the inside of the chamber.

15. 15. The joining method for superconductors according to claim 14, wherein said cooling step comprises a cooling unit supplying a cooling gas into said chamber in accordance with the temperature and pressure inside said chamber.

16. 16. The joining method for superconductors according to claim 15, wherein the cooling unit cools the first wire portion and the second wire portion that have been heated for the joining process, and cools the first wire portion and the second wire portion that have been heat-treated at a temperature lower than that of the joining process to an initial temperature.

17. 12. The joining method for superconductors according to claim 11, wherein an auxiliary joint is disposed between the first wire part and the second wire part.

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