Iron-based superconducting material post-annealing device and post-annealing method thereof

Abstract

The application discloses a kind of iron-based superconducting material post annealing device and its post annealing method, it is related to post annealing equipment technical field, device includes annealing chamber, the upper end opening of annealing chamber is equipped with detachable top cover, the outside of annealing chamber is equipped with heating device, the inside of annealing chamber is equipped with temperature measuring device;It also includes air inlet gas path, vacuum air path, exhaust gas path and connecting pipeline, one end of air inlet gas path is connected with air inlet gas source, the other end is inserted into annealing chamber, one end of vacuum air path is used to connect vacuum pump, the other end is inserted into annealing chamber, one end of exhaust gas path is inserted into primary container, the other end is inserted into annealing chamber, one end of connecting pipeline is inserted into secondary container, the other end is inserted into primary container, and recovery liquid is contained in secondary container.The application can be used to remove the impurity phase in iron-based superconducting material.

Description

Technical Field

[0001] This invention relates to the field of post-annealing equipment technology, and in particular to a post-annealing device and method for iron-based superconducting materials. Background Technology

[0002] Iron-based superconducting materials possess excellent high-field properties, making them promising for large-scale applications. Among the many iron-based superconducting materials with different crystal structures, those containing alkali metal elements exhibit even superior properties. For example, Ba... 1-x K x Fe2As2, Ba 1-x Na x Fe2As2, CaKFe4As4, LiFeAs, (Li, Fe)HOFeSe, KyFe 2-x Se2 superconductors, characterized by high superconducting transition temperatures, low anisotropy, and high upper critical fields, are widely used in the fabrication of single crystals, wires, strips, and thin films. For practical applications, the purity of iron-based superconducting materials directly affects their superconductivity. However, iron-based superconducting materials containing alkali metals often contain numerous alkali metal impurities, alkali metal compound impurities, or other impurity phases. These impurity phases have low melting points, easily melt and wet the grains at high temperatures, and exist within grain boundaries, severely hindering intergranular current transport. Therefore, finding a simple and effective method to remove these impurity phases is crucial for the practical application of iron-based superconducting materials. Summary of the Invention

[0003] The purpose of this invention is to provide a post-annealing apparatus and method for iron-based superconducting materials, which solves the technical problems existing in the prior art and can effectively remove impurity phases in iron-based superconducting materials.

[0004] To achieve the above objectives, the present invention provides the following solution:

[0005] This invention discloses a post-annealing device for iron-based superconducting materials, including an annealing chamber, a detachable top cover at the upper end of the annealing chamber, a heating device on the outside of the annealing chamber, a temperature measuring device inside the annealing chamber, and a vibration device at the bottom of the annealing chamber, on which iron-based superconducting materials are placed.

[0006] It also includes an intake air path, a vacuum air path, an exhaust air path, and a connecting pipe. One end of the intake air path is connected to an intake air source, and the other end extends into the annealing chamber. One end of the vacuum air path is used to connect to a vacuum pump, and the other end extends into the annealing chamber. One end of the exhaust air path extends into the primary container, and the other end extends into the annealing chamber. One end of the connecting pipe extends into the secondary container, and the other end extends into the primary container. The secondary container contains the recovered liquid.

[0007] Preferably, the annealing chamber and the annealing top cover are made of one or more of metal, quartz glass, and ceramic, and the leakage rate of the annealing chamber at a temperature of 0-1200℃ is <10%. -9 Pa·m 3 / s;

[0008] The bottom of the annealing chamber is equipped with a vibration device, on which iron-based superconducting materials are placed. The vibration device is a vibration table, and the contact part between the vibration table and the iron-based superconducting materials is made of ceramic. The operating frequency of the vibration table is 0-1000Hz.

[0009] Preferably, the heating device is a resistance wire or a silicon carbide rod, the highest temperature in the annealing chamber can reach 1200℃, and the temperature difference between various points inside the annealing chamber is <5℃.

[0010] The temperature measuring device is a thermometer, which includes multiple platinum-rhodium thermocouples arranged sequentially from top to bottom.

[0011] Preferably, the port of the air intake passage located inside the annealing chamber is lower than half the height of the annealing chamber; the ports of the vacuum passage and the exhaust passage located inside the annealing chamber are both higher than half the height of the annealing chamber.

[0012] An intake valve is provided in the intake air path, a vacuum valve is provided in the vacuum air path, and an exhaust valve is provided in the exhaust air path.

[0013] Preferably, the recovered liquid is water, oil, or liquid dry ice.

[0014] This invention also discloses a post-annealing method for an iron-based superconducting material post-annealing apparatus, comprising the following steps:

[0015] S1. Place the iron-based superconducting material in the annealing chamber and then cover it with the annealing top cover;

[0016] S2. Perform gas washing treatment on the annealing chamber;

[0017] S3. Turn on the vibration device;

[0018] S4. The sample is heated and annealed under vacuum, continuous vacuum, or flowing atmosphere conditions.

[0019] S5. After the annealing chamber has cooled to room temperature, open the annealing top cover and take out the iron-based superconducting material.

[0020] Preferably, the iron-based superconducting material in step S1 is a superconducting material that has already formed a phase. The crystal structure of the iron-based superconducting material contains alkali metal elements, including iron-based superconducting single crystals, iron-based superconducting thin films, iron-based superconducting polycrystalline bulk materials, iron-based superconducting polycrystalline powders, or iron-based superconducting wires and strips.

[0021] Preferably, the gas washing process in step S2 includes first evacuating the annealing chamber to make the vacuum level inside the annealing chamber less than 3 × 10⁻⁶. -2 Pa, and then inert gas is introduced into the annealing chamber through the intake air passage;

[0022] The gas washing process should be performed at least twice.

[0023] Preferably, the vibration frequency of the vibration device in step S3 is 0-1000Hz.

[0024] Preferably, the vacuum state in step S4 is such that the vacuum path, intake path, and exhaust path are closed, and the vacuum level in the annealing chamber is less than 3 × 10⁻⁶. -2 Pa;

[0025] Continuous vacuuming involves keeping the intake and exhaust air passages closed while continuously evacuating the annealing chamber with the vacuum passage open, maintaining a vacuum level of less than 10 ohms in the annealing chamber. -2 Pa;

[0026] The flow atmosphere is characterized by a closed vacuum path, an open inlet and outlet gas path, and continuous introduction of inert gas into the annealing chamber at a flow rate of 0.1 ml / s to 1000 ml / s.

[0027] The post-annealing temperature in step S4 is 300-1000℃, and the post-annealing time is 0.5-72 hours.

[0028] The present invention achieves the following technical effects compared to the prior art:

[0029] 1. Heating devices are evenly arranged on the outer wall of the annealing chamber to ensure uniform temperature, which is beneficial to prevent the impurity phase from condensing again at the low temperature end after evaporation.

[0030] 2. The inlet gas path is located relatively low in the annealing chamber, while the outlet gas path and vacuum gas path are located relatively high in the annealing chamber, which facilitates the discharge of evaporated gas.

[0031] 3. The bottom of the annealing chamber is equipped with a vibration table, which can perform high-frequency vibration, which is beneficial for the volatilization of impurities;

[0032] 4. Equipped with a primary container, a secondary container, and a recovery liquid in the secondary container, etc., to condense the evaporated impurities and prevent environmental pollution;

[0033] 5. Post-annealing of iron-based superconducting materials that have already formed phases is a simple and easy-to-operate method.

[0034] 6. Post-annealing of iron-based superconducting materials is carried out under vacuum, continuous vacuum, or flowing atmosphere. Vacuum environment helps to reduce the saturated vapor pressure of impurity phase, thereby promoting impurity phase evaporation; continuous vacuum environment helps to continuously remove the evaporated impurity phase, thereby accelerating impurity phase removal; continuous flowing atmosphere helps to carry away the evaporated impurity phase, reduce the saturated vapor pressure of impurity phase near the sample, thereby maintaining the continuous evaporation of impurity phase. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the post-annealing device for iron-based superconducting materials according to an embodiment of the present invention;

[0037] In the diagram: 1-annealing chamber; 2-heating device; 3-annealing top cover; 4-vibration table; 5-iron-based superconducting material; 6-temperature measuring device; 7-inlet gas path; 8-inlet valve; 9-vacuum path; 10-vacuum valve; 11-exhaust gas path; 12-exhaust valve; 13-primary container; 14-connecting pipeline; 15-secondary container; 16-recovered liquid. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] The purpose of this invention is to provide a post-annealing apparatus and method for iron-based superconducting materials, which solves the technical problems existing in the prior art and can effectively remove impurity phases in iron-based superconducting materials.

[0040] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] Example 1

[0042] like Figure 1As shown, this embodiment provides a post-annealing apparatus for iron-based superconducting materials, including an annealing chamber 1. The upper opening of the annealing chamber 1 is provided with a detachable annealing top cover 3. The annealing chamber 1 and the annealing top cover 3 can be connected using a conventional capping method, or by adding bolts for fixing. A sealing ring can also be added at the connection point to enhance its sealing performance. A heating device 2 is provided on the outside of the annealing chamber 1 to heat the annealing chamber 1, thereby providing heat to the iron-based superconducting material 5 inside the annealing chamber 1. A temperature measuring device 6 is provided inside the annealing chamber 1 to monitor the temperature inside the annealing chamber 1 in real time.

[0043] It also includes an intake air passage 7, a vacuum air passage 9, an exhaust air passage 11, and a connecting pipe 14. The intake air passage 7, vacuum air passage 9, and exhaust air passage 11 all pass through the annealing top cover 3 and extend into the annealing chamber 1. Specifically, one end of the intake air passage 7 is connected to an intake air source, and the other end extends into the annealing chamber 1. The intake air source is a gas cylinder containing rare gases. One end of the vacuum air passage 9 is used to connect to a vacuum pump, and the other end extends into the annealing chamber 1. One end of the exhaust air passage 11 extends into the primary container 13, and the other end extends into the annealing chamber 1. One end of the connecting pipe 14 extends into the secondary container 15, and the other end extends into the primary container 13. The secondary container 15 contains a recovery liquid 16, which is used to recover the discharged waste gas.

[0044] In practical use, open the annealing top cover 3, place the iron-based superconducting material 5 on the vibration device, and close the annealing top cover 3. Open the vacuum passage 9 to evacuate the annealing chamber 1. After the pressure reaches the expected pressure, open the inlet gas passage 7 to introduce argon gas into the annealing chamber 1, repeating the evacuation-gas-inlet process twice. After evacuating the chamber to the expected pressure again, close the vacuum passage 9. Turn on the vibration device and adjust the vibration frequency. Heat the annealing chamber 1 until its internal temperature reaches the expected temperature and maintain this temperature. After the internal temperature of the annealing chamber 1 cools to room temperature, open the inlet gas passage 7 to bring the pressure in the annealing chamber 1 to one atmosphere. Open the annealing top cover 3 and remove the iron-based superconducting material 5.

[0045] In this embodiment, the annealing chamber 1 and the annealing top cover 3 are made of one or more of the following materials: metal, quartz glass, and ceramic. When two or more materials are used, it is a composite material. The metals include, but are not limited to, Inconel alloy, 316 stainless steel, and tantalum. The leakage rate of the annealing chamber 1 at temperatures between 0-1200°C is <10%. -9 Pa·m 3 / s.

[0046] A vibration device is installed at the bottom of the annealing chamber 1, capable of high-frequency vibration. The iron-based superconducting material 5 is placed on the vibration device, which facilitates the volatilization of impurities. The vibration device is an existing vibration table 4. The contact area between the vibration table 4 and the iron-based superconducting material 5 is made of ceramic, giving it high-temperature resistance. The vibration table 4 operates at a frequency of 0-1000Hz, and the operator can adjust the operating frequency of the vibration table 4 according to actual conditions.

[0047] In this embodiment, the heating device 2 includes, but is not limited to, existing resistance wires or silicon carbide rods, both of which have the function of converting electrical energy into heat energy. The heating device 2 needs to be uniformly arranged on the outside of the annealing chamber 1 so that the highest temperature inside the annealing chamber 1 can reach 1200°C, and the temperature difference between various points inside the annealing chamber 1 is <5°C, to avoid the impurity phase from evaporating and then condensing again at the low temperature end.

[0048] The temperature measuring device 6 is a thermometer, which includes multiple platinum-rhodium thermocouples arranged sequentially from top to bottom to test the temperature at different heights.

[0049] In this embodiment, the end of the intake air passage 7 located inside the annealing chamber 1 is lower than half the height of the annealing chamber 1. This allows the inert gas delivered by the intake air passage 7 to quickly fill the entire annealing chamber 1 and expel the gas inside the annealing chamber 1. The ends of the vacuum passage 9 and the exhaust air passage 11 located inside the annealing chamber 1 are both higher than half the height of the annealing chamber 1, which facilitates the discharge of evaporated gas.

[0050] In addition, an intake valve 8 is provided on the intake air passage 7, a vacuum valve 10 is provided on the vacuum air passage 9, and an exhaust valve 12 is provided on the exhaust air passage 11. The flow of each air passage is controlled by opening and closing each valve.

[0051] Furthermore, a controller can be added. The aforementioned electrical components, such as the vibration table 4, thermometer, air inlet valve 8, vacuum valve 10, exhaust valve 12, and heating device 2, are all electrically connected to the controller, thereby enabling remote control by the operator. The controller can be a PLC controller, a microcontroller controller, or a backend computer, etc.

[0052] Furthermore, flow sensors can be installed on the inlet valve 8, vacuum valve 10, and exhaust valve 12 to monitor the flow rate in each pipeline. A pressure sensor can also be installed inside the annealing chamber 1 to monitor the gas pressure within the annealing chamber 1.

[0053] In this embodiment, the recovered liquid 16 is water, oil or liquid dry ice, and its function is to recover the evaporated gas discharged from the exhaust gas passage 11.

[0054] Example 2

[0055] This embodiment provides a post-annealing method for an iron-based superconducting material post-annealing apparatus, based on the iron-based superconducting material post-annealing apparatus of claim 1, comprising the following steps:

[0056] S1. Place the iron-based superconducting material 5 on the vibration table 4 in the annealing chamber 1, and then cover it with the annealing top cover 3.

[0057] S2. Perform gas washing treatment on annealing chamber 1.

[0058] S3. Turn on the vibration device (i.e., vibration table 4).

[0059] S4. The sample is heated and annealed under vacuum, continuous vacuum, or flowing atmosphere conditions.

[0060] S5. After the annealing chamber 1 has cooled to room temperature, open the annealing top cover 3 and take out the iron-based superconducting material 5 to complete the entire working process.

[0061] In this embodiment, the iron-based superconducting material 5 in step S1 is a superconducting material that has already formed a phase. The crystal structure of the iron-based superconducting material 5 contains alkali metal elements, including iron-based superconducting single crystal, iron-based superconducting thin film, iron-based superconducting polycrystalline bulk material, iron-based superconducting polycrystalline powder, or iron-based superconducting wire and strip.

[0062] In this embodiment, the gas washing process in step S2 includes first evacuating the annealing chamber 1 to make the vacuum level in the annealing chamber 1 less than 3 × 10⁻⁶. -2 Pa, and then inert gas is introduced into the annealing chamber 1 through the air inlet passage 7. The inert gas includes, but is not limited to, argon.

[0063] The gas scrubbing process should be performed at least twice (including twice).

[0064] In this embodiment, the vibration frequency of the vibration device in step S3 is 0-1000Hz, and the operator can adjust the specific operating frequency of the vibration table 4 according to the actual situation.

[0065] In this embodiment, the vacuum state in step S4 is such that the vacuum valve 10 in the vacuum path 9, the inlet valve 8 in the inlet path 7, and the exhaust valve 12 in the exhaust path 11 are closed, and the vacuum degree in the annealing chamber 1 is less than 3 × 10⁻⁶. -2 Pa.

[0066] The continuous vacuuming process involves keeping the intake valve 8 in the intake air passage 7 and the exhaust valve 12 in the exhaust air passage 11 closed, while opening the vacuum valve 10 in the vacuum passage 9 to continuously evacuate the annealing chamber 1, ensuring that the vacuum level inside the annealing chamber 1 is less than 10. -2 Pa.

[0067] The flow atmosphere is as follows: the vacuum valve 10 in the vacuum circuit 9 is closed, the inlet valve 8 in the inlet gas circuit 7 and the exhaust valve 12 in the exhaust gas circuit 11 are opened, and inert gas is continuously introduced into the annealing chamber 1 at a flow rate of 0.1 ml / s-1000 ml / s.

[0068] In addition, the post-annealing temperature in step S4 is 300-1000℃, and the post-annealing time is 0.5-72 hours.

[0069] Example 3

[0070] This embodiment provides a post-annealing apparatus for iron-based superconducting materials. The technical features disclosed in this embodiment are basically the same as those disclosed in Embodiment 1, with the following differences:

[0071] In this embodiment, the annealing chamber 1 and the annealing top cover 3 are made of metal, and the operating frequency of the vibration table 4 is 0-500Hz.

[0072] In this embodiment, the heating device 2 is a resistance wire, and it is evenly distributed within the height range of the annealing chamber 1.

[0073] In this embodiment, the recovered liquid 16 in the secondary container 15 is water.

[0074] In actual operation, open the annealing top cover 3 and place the Ba... 1-x K x The Fe2As2 superconducting polycrystalline bulk material is placed on the vibration table 4, and the annealing top cover 3 is closed. The inlet valve 8 and the exhaust valve 12 are closed, and the vacuum valve 10 is opened to evacuate the annealing chamber 1 until the pressure reaches 2 × 10⁻⁶. -2 Close vacuum valve 10 when Pa is reached. Open inlet valve 8 to purge argon gas into annealing chamber 1, repeating the evacuation-purge process twice. Open vacuum valve 10 again to evacuate annealing chamber 1 to 2×10⁻⁶ Pa. -2 Pa, close vacuum valve 10. Turn on the vibration device, and set the vibration frequency to 30Hz. Heat the annealing chamber 1 to 300℃ and hold for 72 hours. After the internal temperature of the annealing chamber 1 cools to room temperature, open the air inlet valve 8 to make the chamber pressure reach one atmosphere, open the annealing top cover 3, and take out the iron-based superconducting material 5.

[0075] Example 4

[0076] This embodiment provides a post-annealing apparatus for iron-based superconducting materials. The technical features disclosed in this embodiment are basically the same as those disclosed in Embodiment 1, with the following differences:

[0077] In this embodiment, the annealing chamber 1 and the annealing top cover 3 are made of quartz glass, and the leakage rate of the annealing chamber 1 is <5×10⁻⁶ at a temperature of 0-1200℃. -10 Pa·m 3 / s, the bottom of the annealing chamber 1 is equipped with a vibration table 4, the part of the vibration table 4 that contacts the iron-based superconducting material 5 is made of ceramic, and the working frequency of the vibration table 4 is 0-300Hz.

[0078] In this embodiment, the heating device 2 is a silicon carbide rod, which is evenly distributed within the height range of the annealing chamber 1. The temperature inside the annealing chamber 1 reaches a maximum of 1200°C. The temperature inside the annealing chamber 1 is uniform, and the temperature difference between different points inside is <3°C.

[0079] In this embodiment, the port of the intake air passage 7 in the annealing chamber 1 is below 1 / 3 of the height of the annealing chamber 1, and the ports of the vacuum passage 9 and the exhaust air passage 11 in the annealing chamber 1 are above 2 / 3 of the height of the annealing chamber 1.

[0080] In this embodiment, the recovered liquid 16 in the secondary container 15 is oil.

[0081] In actual operation, open the annealing top cover 3 and place the Ba... 1-x Na x Fe₂As₂ superconducting polycrystalline powder is placed on the vibration table 4, and the annealing top cover 3 is closed. The inlet valve 8 and the exhaust valve 12 are closed, and the vacuum valve 10 is opened to evacuate the annealing chamber 1 until the pressure reaches 1×10⁻⁶. -2 Close vacuum valve 10 when the pressure reaches Pa. Open inlet valve 8 to purge nitrogen into annealing chamber 1, repeating the evacuation-purge cycle three times. Open vacuum valve 10 again to evacuate annealing chamber 1 to a pressure less than 10 Pa. -2 Pa. Turn on the vibration device, and set the vibration frequency to 0 Hz. Heat the annealing chamber 1 to an internal temperature of 800°C and hold for 24 hours. After the internal temperature of the annealing chamber 1 cools to room temperature, close the vacuum valve 10 and open the air inlet valve 8 to bring the chamber pressure to one atmosphere. Open the annealing top cover 3 and remove the iron-based superconducting material 5.

[0082] Example 5

[0083] This embodiment provides a post-annealing apparatus for iron-based superconducting materials. The technical features disclosed in this embodiment are basically the same as those disclosed in Embodiment 1, with the following differences:

[0084] In this embodiment, both the annealing chamber 1 and the annealing top cover 3 are made of ceramic, and the leakage rate of the annealing chamber 1 is <10% at 0-1200℃. -10 Pa·m 3 / s.

[0085] In this embodiment, the heating device 2 is a silicon carbide rod, which is evenly distributed within the height range of the annealing chamber 1. The temperature inside the annealing chamber 1 reaches a maximum of 1200°C. The temperature inside the chamber is uniform, and the temperature difference between different points inside is <2°C.

[0086] In this embodiment, the port of the intake air passage 7 in the annealing chamber 1 is below 1 / 4 of the height of the annealing chamber 1, while the ports of the vacuum passage 9 and the exhaust air passage 11 in the annealing chamber 1 are above 3 / 4 of the height of the annealing chamber 1.

[0087] In this embodiment, the recovered liquid 16 in the secondary container 15 is dry ice.

[0088] In actual operation, open the annealing top cover 3, place the CaKFe4As4 superconducting wire strip on the vibration table 4, and close the annealing top cover 3. Close the inlet valve 8 and the exhaust valve 12, and open the vacuum valve 10 to evacuate the annealing chamber 1 until the pressure reaches 5×10⁻⁶. -3 Close vacuum valve 10 when Pa is reached. Open inlet valve 8 to purge argon gas into annealing chamber 1, repeating the vacuum-gas-purge cycle three times. Open inlet valve 8 to purge argon gas into annealing chamber 1, then open exhaust valve 12 to create a flowing atmosphere in annealing chamber 1 with a gas flow rate of 10 ml / s. Turn on the vibration device at a vibration frequency of 1000 Hz. Heat annealing chamber 1 to reach an internal temperature of 1000℃ and hold for 0.5 hours. After the internal temperature of annealing chamber 1 cools to room temperature and the pressure in annealing chamber 1 reaches one atmosphere, open the annealing top cover 3 and remove the iron-based superconducting material 5.

[0089] This specification uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A post-annealing apparatus for iron-based superconducting materials, characterized in that: It includes an annealing chamber, the upper opening of which is provided with a detachable annealing top cover, a heating device is provided on the outside of the annealing chamber, and a temperature measuring device is provided inside the annealing chamber; It also includes an intake air path, a vacuum air path, an exhaust air path, and a connecting pipe. One end of the intake air path is connected to an intake air source, and the other end extends into the annealing chamber. One end of the vacuum air path is used to connect to a vacuum pump, and the other end extends into the annealing chamber. One end of the exhaust air path extends into the primary container, and the other end extends into the annealing chamber. One end of the connecting pipe extends into the secondary container, and the other end extends into the primary container. The secondary container contains the recovered liquid. The bottom of the annealing chamber is equipped with a vibration device, on which iron-based superconducting materials are placed. The vibration device is a vibration table, and the contact part between the vibration table and the iron-based superconducting material is made of ceramic. Iron-based superconducting materials are superconducting materials that have already formed a phase. The crystal structure of iron-based superconducting materials contains alkali metal elements.

2. The post-annealing apparatus for iron-based superconducting materials according to claim 1, characterized in that: The leakage rate of the annealing chamber at temperatures ranging from 0 to 1200°C is <10%. -9 Pa·m 3 / s; The vibration table operates at a frequency of 0-1000 Hz.

3. The post-annealing apparatus for iron-based superconducting materials according to claim 1, characterized in that: The heating device is a resistance wire or a silicon carbide rod, and the highest temperature in the annealing chamber can reach 1200℃, with a temperature difference of <5℃ between points inside the annealing chamber. The temperature measuring device is a thermometer, which includes multiple platinum-rhodium thermocouples arranged sequentially from top to bottom.

4. The post-annealing apparatus for iron-based superconducting materials according to claim 1, characterized in that: The port of the air intake passage located inside the annealing chamber is lower than half the height of the annealing chamber; the ports of the vacuum passage and the exhaust passage located inside the annealing chamber are both higher than half the height of the annealing chamber. An intake valve is provided in the intake air path, a vacuum valve is provided in the vacuum air path, and an exhaust valve is provided in the exhaust air path.

5. The post-annealing apparatus for iron-based superconducting materials according to claim 1, characterized in that: The recovered liquid is water, oil, or liquid dry ice.

6. A post-annealing method for a post-annealing apparatus for iron-based superconducting materials, characterized in that, The post-annealing apparatus for iron-based superconducting materials according to any one of claims 1-5 includes the following steps: S1. Place the iron-based superconducting material in the annealing chamber and then cover it with the annealing top cover; S2. Perform gas washing treatment on the annealing chamber; S3. Turn on the vibration device; S4. The sample is heated and annealed under vacuum, continuous vacuum, or flowing atmosphere conditions. S5. After the annealing chamber has cooled to room temperature, open the annealing top cover and take out the iron-based superconducting material.

7. The post-annealing method of the post-annealing apparatus for iron-based superconducting materials according to claim 6, characterized in that: The iron-based superconducting material in step S1 includes iron-based superconducting single crystals, iron-based superconducting polycrystalline bulk materials, or iron-based superconducting polycrystalline powders.

8. The post-annealing method of the post-annealing apparatus for iron-based superconducting materials according to claim 6, characterized in that: Step S2, the gas washing process, includes first evacuating the annealing chamber to a vacuum level of less than 3 × 10⁻⁶. -2 Pa, and then inert gas is introduced into the annealing chamber through the intake air passage; The gas washing process should be performed at least twice.

9. The post-annealing method of the post-annealing apparatus for iron-based superconducting materials according to claim 6, characterized in that: The vibration frequency of the vibration device in step S3 is 0-1000 Hz.

10. The post-annealing method of the post-annealing apparatus for iron-based superconducting materials according to claim 6, characterized in that: In step S4, the vacuum state is maintained by keeping the vacuum path, intake path, and exhaust path closed, and the vacuum level in the annealing chamber is less than 3 × 10⁻⁶. -2 Pa; Continuous vacuuming involves keeping the intake and exhaust air passages closed while continuously evacuating the annealing chamber with the vacuum passage open, maintaining a vacuum level of less than 10 ohms in the annealing chamber. -2 Pa; The flow atmosphere is characterized by a closed vacuum path, an open inlet gas path and an open exhaust gas path, with inert gas continuously introduced into the annealing chamber at a flow rate of 0.1 ml / s to 1000 ml / s. The post-annealing temperature in step S4 is 300-1000℃, and the post-annealing time is 0.5-72 hours.

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