Lu-doped high-temperature superconducting raw material, preparation method and use thereof

Abstract

The application relates to the technical field of superconducting materials, in particular to a Lu-doped high-temperature superconducting raw material and a preparation method and application thereof. The application provides a Lu-doped high-temperature superconducting raw material, which is a Lu-doped EuBaCuO superconducting material. In the application, Lu doping is introduced into the EuBaCuO superconducting material, and then the target material prepared from the raw material can generate strip-shaped nanocolumns in the formed superconducting thin film, so that pinning centers appear in the thin film, a pinning effect is generated, and the thin film has good magnetic resistance, electric performance and mechanical performance under low temperature and high field.

Description

Technical Field

[0001] This invention relates to the field of superconducting materials technology, specifically to a Lu-doped high-temperature superconducting raw material, its preparation method, and its applications. Background Technology

[0002] High-temperature superconducting thin film materials, due to their core properties such as high current carrying capacity, perfect diamagnetism, and quantum tunneling (Josephson effect), have shown significant application value in fields such as power transmission, strong magnetic field devices, and quantum computing. Among them, RBa2Cu3O 7-δ Superconducting thin film materials have become a focus of industry attention due to their high critical temperature.

[0003] In related technologies, the production of RBa2Cu3O 7-δ There are many processing routes for superconducting thin films, such as pulsed laser deposition (PLD), metal-organic deposition (MOD), chemical vapor deposition (MOCVD), and reactive sputtering epitaxy (RCE). Fujikura Corporation of Japan, Superox of Russia, Bruker of Germany, and Shanghai Superconducting Technologies Co., Ltd. (SST) all use IBAD / PLD composite technology to produce RBa2Cu3O. 7-δ Superconducting tapes have a high critical current at 77K and 0T, but poor diamagnetism at low temperature and high field, which leads to weakened electrical performance and a low current boost factor. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the limitations of the prepared RBa2Cu3O in related technologies. 7-δ Superconducting thin film materials suffer from poor diamagnetism at low temperatures and high fields, which leads to weakened electrical properties and a low current boost factor. Therefore, this paper provides a Lu-doped high-temperature superconducting raw material, its preparation method, and its applications.

[0005] This invention provides a Lu-doped high-temperature superconducting raw material, wherein the Lu-doped high-temperature superconducting raw material is a Lu-doped EuBaCuO superconducting material.

[0006] Preferably, the general chemical formula of the Lu-doped high-temperature superconducting raw material is: Eu x Lu y Ba2Cu3O 7－& Where 0.75≤x≤0.99, x+y=1.

[0007] Preferably, the general chemical formula of the Lu-doped high-temperature superconducting raw material is: Eu 0.985 Lu 0.015 Ba2Cu3O 7－& .

[0008] Preferably, the raw materials for the Lu-doped high-temperature superconducting raw material include europium source, lutetium source, barium source and copper source; wherein the purity of the europium source is greater than or equal to 99.999%; the purity of the lutetium source is greater than or equal to 99.999%; the purity of the barium source is greater than or equal to 99.995%; and the purity of the copper source is greater than or equal to 99.999%.

[0009] Preferably, the general chemical formula of the Lu-doped high-temperature superconducting raw material is: Eu 0.985 Lu 0.015 Ba2Cu3O 7－& .

[0010] The present invention also provides a method for preparing the above-mentioned Lu-doped high-temperature superconducting raw material, comprising the following steps: mixing europium source, lutetium source, barium source and copper source to obtain a mixture, sintering and pulverizing the mixture, washing, drying and sieving the pulverized material to obtain the Lu-doped high-temperature superconducting raw material.

[0011] Optionally, the mixing process involves mixing europium source, lutetium source, barium source and copper source in a mixer at 12-15 rpm for 8-9 hours.

[0012] Optionally, the mixer is a three-dimensional mixer.

[0013] Optionally, the sintering process also includes a cooling process, wherein the temperature is reduced to 150-250°C at a rate of 3-4°C / min after sintering, and then naturally cooled in an environment of 20-40°C.

[0014] Optionally, the washing process of the pulverized material includes mixing the pulverized material and detergent at a mass ratio of 1:(2.5-3.5) for 30 minutes, followed by rotary evaporation, and then repeating the above washing process 2-3 times to complete the washing process of the pulverized material.

[0015] Optionally, the drying process is heating and vacuum drying.

[0016] Preferably, the europium source includes, but is not limited to, europium oxide; and / or,

[0017] The lutetium source includes, but is not limited to, lutetium oxide; and / or,

[0018] The barium source includes, but is not limited to, barium carbonate; and / or

[0019] The copper source includes, but is not limited to, copper oxide.

[0020] Preferably, the purity of the europium source is greater than or equal to 99.999%; the particle size of the europium source is 1-1.2 μm; and / or,

[0021] The lutetium source has a purity greater than or equal to 99.999%; the lutetium source has a particle size of 1-1.2 μm; and / or,

[0022] The purity of the barium source is greater than or equal to 99.995%; the particle size of the barium source is 1-1.5 μm; and / or,

[0023] The purity of the copper source is greater than or equal to 99.999%; the particle size of the copper source is 0.5-1μm.

[0024] Preferably, the europium source is prepared by grinding, washing, rotary evaporating, and sieving the initial europium source to obtain the europium source.

[0025] Wherein, the pressure of the air jet mill is 0.15-0.25 MPa; the gas used in the air jet mill is nitrogen with a purity greater than or equal to 99.999%; the detergent used in the washing process is water with a conductivity less than or equal to 0.05 S / m; and / or,

[0026] The method for preparing the lutetium source is to crush the initial lutetium source by air jet milling, washing, rotary evaporation, and sieving to obtain the lutetium source;

[0027] Wherein, the pressure of the air jet mill is 0.15-0.25 MPa; the gas used in the air jet mill is nitrogen with a purity greater than or equal to 99.999%; the detergent used in the washing process is water with a conductivity less than or equal to 0.05 S / m; and / or,

[0028] The barium source is prepared by grinding, washing, rotary evaporating, and sieving the initial barium source through an air jet mill to obtain the barium source.

[0029] Wherein, the pressure of the air jet mill is 0.15-0.25 MPa; the gas used in the air jet mill is nitrogen with a purity greater than or equal to 99.999%; the detergent used in the washing process is water with a conductivity less than or equal to 0.05 S / m; and / or,

[0030] The copper source is prepared by grinding, washing, rotary evaporating, and sieving the initial copper source through an air jet mill to obtain the copper source.

[0031] The pressure of the air jet mill is 0.15-0.25 MPa; the gas used in the air jet mill is nitrogen with a purity greater than or equal to 99.999%; and the detergent used in the washing process is water with a conductivity less than or equal to 0.05 S / m.

[0032] The initial europium source, initial lutetium source, initial barium source, and initial copper source used in this application are all commercially available superior-grade pure products (purity of 99.8-99.99%), and the particle size of the products is in the micrometer range.

[0033] Optionally, in the preparation methods of the europium source, the lutetium source, the barium source, and the copper source, the air jet mill is selected from the ultra-micro air jet mill.

[0034] Optionally, the washing process of the europium source preparation method, the lutetium source preparation method, the barium source preparation method, and the copper source preparation method involves washing three times with detergent, and the mass ratio of detergent to the washed object in each washing process is (2.5-3.5):1.

[0035] In this application, an air jet mill is used to pulverize the material. Compared with media ball milling, it can use air jets to break up the particles that are stuck together due to high-temperature solid-phase reaction, thus maintaining the original growth morphology of the product and avoiding the damage to the original crystal form and the introduction of impurities caused by media ball milling.

[0036] Preferably, based on metal stoichiometry, the molar ratio of europium, lutetium, barium, and copper in the mixture is (0.75-0.99):(0.01-0.25):(1.9-2.1):(2.9-3.1); and / or,

[0037] The mixture is sintered at a temperature of 980-1010℃ for 6-7 hours in an oxygen atmosphere; and / or,

[0038] The pulverization process employs an air jet mill, wherein the pressure of the air jet mill is 0.25-0.35 MPa; the gas used in the air jet mill is nitrogen with a purity greater than or equal to 99.999%; and / or,

[0039] The detergent used in the washing process of the crushed material is water with an electrical conductivity of less than or equal to 0.05 S / m.

[0040] Optionally, the mass ratio of detergent to pulverized material in the washing process is (2.5-3.5):1.

[0041] In this application, the sintering atmosphere is oxygen, which allows for continuous replenishment of oxygen, ensuring the reaction takes place in an oxygen-rich atmosphere and improving the electrical, diamagnetic, and mechanical properties of Lu-doped high-temperature superconducting raw materials.

[0042] The present invention also provides a high-temperature superconducting target material comprising the Lu-doped high-temperature superconducting raw material described above, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method described above.

[0043] The present invention also provides a method for preparing the high-temperature superconducting target material described above, comprising the following steps: pressing the Lu-doped high-temperature superconducting raw material described above, or the Lu-doped high-temperature superconducting raw material prepared by the above preparation method, to obtain a blank, sintering and slicing the blank to obtain the high-temperature superconducting target material.

[0044] Preferably, the pressing is isostatic pressing; the pressing pressure is 180-200 MPa; and / or,

[0045] The sintering temperature is 985-1010℃, and the sintering time is 8-10 hours; the sintering atmosphere is oxygen, with an oxygen purity greater than or equal to 99.999%; and / or,

[0046] The high-temperature superconducting target material obtained by slicing is a disc; the disc diameter is 50-60mm and the thickness is 4-6mm.

[0047] Optionally, the pressing process to obtain the blank is carried out in a rubber mold.

[0048] Optionally, the sintered body obtained by sintering the blank is a column with a diameter of 50-60 mm and a thickness of 30-40 mm.

[0049] The present invention also provides a superconducting thin film, wherein the material of the superconducting thin film is selected from the Lu-doped high-temperature superconducting raw material described above, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method described above, or the high-temperature superconducting target material described above, or the high-temperature superconducting target material prepared by the preparation method described above.

[0050] The present invention also provides a method for preparing the superconducting thin film described above, comprising the following steps: depositing the Lu-doped high-temperature superconducting raw material described above, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method described above, or the high-temperature superconducting target material described above, or the high-temperature superconducting target material prepared by the preparation method described above, on a substrate to obtain the superconducting thin film.

[0051] Optionally, the deposition method is selected from pulsed laser deposition (PLD) or ion beam assisted deposition (IBAD).

[0052] The technical solution of this invention has the following advantages:

[0053] This invention provides a Lu-doped high-temperature superconducting raw material, wherein the Lu-doped high-temperature superconducting raw material is a Lu-doped EuBaCuO superconducting material.

[0054] In this invention, by introducing Lu doping into EuBaCuO superconducting material, strip-shaped nanopillars (approximately 7-10 nm in diameter) can be generated in the superconducting thin film made from the raw material, thereby creating pinning centers in the film and generating a pinning effect. This results in the film having good diamagnetic properties, electrical properties, and mechanical properties under low temperature and high field conditions.

[0055] Furthermore, the preparation method provided by the present invention includes a process for processing superior-grade pure raw materials, thereby obtaining raw materials with higher purity, which in turn improves the purity of the final Lu-doped high-temperature superconducting raw material and further improves the electrical properties of the final prepared thin film. Attached Figure Description

[0056] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0057] Figure 1 This is an appearance diagram of the high-temperature superconducting target material prepared in Example 2 of the present invention;

[0058] Figure 2 This is a graph showing the relationship between current and voltage after the high-temperature superconducting thin film prepared from the high-temperature superconducting target material prepared in Example 2 of this invention is cut and tested.

[0059] Figure 3 This is a transmission electron microscope (TEM) image of a high-temperature superconducting thin film prepared from the high-temperature superconducting target material prepared in Example 2 of this invention.

[0060] Figure 4 This is a graph showing the relationship between current and voltage after the high-temperature superconducting thin film prepared from the high-temperature superconducting target material prepared in Comparative Example 2 of this invention is slit. Detailed Implementation

[0061] The following embodiments are provided to better understand the present invention and are not intended to limit the preferred embodiments. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the scope of protection of the present invention. Where specific experimental steps or conditions are not specified in the embodiments, they can be performed according to the conventional experimental steps or conditions described in the literature in the art. Reagents or instruments used, unless otherwise specified, are all commercially available conventional reagent products.

[0062] The initial europium oxide, initial lutetium oxide, initial barium carbonate, and initial copper oxide used in the examples were all commercially available superior-grade pure products (purity of 99.8-99.99%), and the particle size of the products was in the micrometer range.

[0063] The preparation of europium oxide includes the following steps: the initial europium oxide is pulverized using an ultra-micro air jet mill (the gas used in the air jet mill is 99.999% nitrogen gas at a pressure of 0.2 MPa), then washed three times with ultrapure water with a resistivity of less than 0.05 S / m (the amount of ultrapure water used each time is three times the mass of the initial europium oxide), and then rotary evaporated in a rotary evaporator and sieved to obtain europium oxide with a particle size of 1-1.2 μm and a purity greater than 99.999%.

[0064] The preparation of lutetium oxide includes the following steps: the initial lutetium oxide is pulverized using an ultra-micro air jet mill (the gas used in the air jet mill is 99.999% nitrogen gas at a pressure of 0.2 MPa), then washed three times with ultrapure water with a resistivity of less than 0.05 S / m (the amount of ultrapure water used each time is three times the mass of the initial lutetium oxide), and then rotary evaporated in a rotary evaporator and sieved to obtain lutetium oxide with a particle size of 1-1.2 μm and a purity greater than 99.999%.

[0065] The preparation of barium carbonate includes the following steps: the initial barium carbonate is pulverized using an ultra-micro air jet mill (the gas used in the air jet mill is 99.999% nitrogen gas at a pressure of 0.2 MPa), then washed three times with ultrapure water with a resistivity of less than 0.05 S / m (the amount of ultrapure water used each time is three times the mass of the initial barium carbonate), and then rotary evaporated in a rotary evaporator. After sieving, barium carbonate with a particle size of 1-1.5 μm and a purity greater than 99.995% is obtained.

[0066] The preparation of copper oxide includes the following steps: the initial copper oxide is pulverized using an ultra-micro air jet mill (the gas used in the air jet mill is 99.999% nitrogen gas at a pressure of 0.2 MPa), then washed three times with ultrapure water with a resistivity of less than 0.05 S / m (the amount of ultrapure water used each time is three times the mass of the initial copper oxide), and then rotary evaporated in a rotary evaporator and sieved to obtain copper oxide with a particle size of 0.5-1 μm and a purity greater than 99.999%.

[0067] Example 1

[0068] This embodiment provides a Lu-doped high-temperature superconducting raw material, the preparation method of which includes the following steps:

[0069] Europium oxide, lutetium oxide, barium carbonate, and copper oxide were loaded into a plastic bucket at a mass ratio of 21.36:0.37:48.77:29.51. The mixture was then mixed for 8 hours at 15 rpm on a three-dimensional mixer. The mixture was passed through a 100-mesh dry sieve and then placed in a tightly packed corundum crucible. It was sintered in an oxygen furnace at 1000°C for 6.5 hours. The temperature was then reduced to 200°C at a rate of 3°C / min. After cooling to room temperature, the mixture was then subjected to an ultra-micro air jet mill (using 99.999% nitrogen gas at a pressure of...). The material was pulverized at 0.3 MPa and then washed three times with ultrapure water (resistivity less than 0.05 S / m). Each wash used three times the mass of the material, and the material was stirred in the ultrapure water for 30 minutes. After each wash, the material was subjected to rotary evaporation in a rotary evaporator. This yielded a Lu-doped high-temperature superconducting raw material precursor. The precursor was then vacuum-dried using an oil bath and sieved to obtain Lu-doped high-temperature superconducting raw material with a particle size of 1-2 μm and the chemical formula Eu. 0.985 Lu 0.015 Ba2Cu3O 7－& .

[0070] Lu-doped high-temperature superconducting raw materials with a purity of 99.995% were prepared using inductively coupled plasma (ICP) testing.

[0071] Example 2

[0072] This embodiment provides a high-temperature superconducting target, the preparation method of which includes the following steps:

[0073] The Lu-doped high-temperature superconducting raw material prepared above was placed in a mold and isostatically pressed at 190 MPa to form a blank. Then, it was placed in a high-temperature furnace filled with 99.999% pure oxygen and fired at 1000°C for 9.5 hours to obtain a cylinder with a diameter of 50.8 mm and a thickness of 35 mm. This cylinder was then cut into sheets with a thickness of 5 mm to obtain the high-temperature superconducting target material. Figure 1 As shown.

[0074] Example 3

[0075] This embodiment provides a Lu-doped high-temperature superconducting raw material, the preparation method of which includes the following steps:

[0076] Europium oxide, lutetium oxide, barium carbonate, and copper oxide were loaded into a plastic bucket at a mass ratio of 21.36:0.37:48.77:29.51. The mixture was then mixed on a three-dimensional mixer at 15 rpm for 9 hours. The mixture was then passed through a 100-mesh dry sieve and placed in a tightly packed corundum crucible. It was sintered in an oxygen furnace at 985°C for 6.5 hours. The temperature was then reduced to 200°C at a rate of 4°C / min. After cooling to room temperature, the mixture was then subjected to an ultra-micro air jet mill (using 99.999% nitrogen gas at a pressure of [insert pressure here]). The material was pulverized at 0.3 MPa and then washed three times with ultrapure water with a resistivity of less than 0.05 S / m (each time the amount of ultrapure water used was three times the mass of the material being washed, and the material was stirred in ultrapure water for 30 min each time, and rotary evaporation was performed in a rotary evaporator after each wash) to obtain a Lu-doped high-temperature superconducting raw material precursor. The Lu-doped high-temperature superconducting raw material precursor was then vacuum dried using an oil bath and sieved to obtain Lu-doped high-temperature superconducting raw material with a particle size of 1-2 μm and the chemical formula Eu. 0.985 Lu 0.015 Ba2Cu3O 7－& ;

[0077] Lu-doped high-temperature superconducting raw materials with a purity of 99.995% were prepared using inductively coupled plasma (ICP) testing.

[0078] Example 4

[0079] This embodiment provides a high-temperature superconducting target, the preparation method of which includes the following steps:

[0080] The Lu-doped high-temperature superconducting raw material prepared in Example 3 was placed in a mold and formed into a blank by isostatic pressing at a pressure of 200 MPa. Then, it was placed in a high-temperature furnace with oxygen of 99.999% purity and fired at 985°C for 9.5 hours to obtain a cylinder with a diameter of 50.8 mm and a thickness of 35 mm. The cylinder was then cut into sheets with a thickness of 5 mm to obtain the high-temperature superconducting target material.

[0081] Example 5

[0082] This embodiment provides a Lu-doped high-temperature superconducting raw material, the preparation method of which includes the following steps:

[0083] Initial europium oxide, initial lutetium oxide, initial barium carbonate, and initial copper oxide were loaded into a plastic bucket at a mass ratio of 21.36:0.37:48.77:29.51. The mixture was then mixed for 8 hours at 15 rpm on a three-dimensional mixer. The mixture was then passed through a 100-mesh dry sieve and placed in a tightly packed corundum crucible. It was sintered in an oxygen furnace at 1000℃ for 6.5 hours, then cooled to 200℃ at a rate of 3℃ / min. After cooling to room temperature, the mixture was then subjected to an ultra-micro air jet mill (using 99.999% nitrogen gas). The material was pulverized at a pressure of 0.3 MPa, then washed three times with ultrapure water (resistivity less than 0.05 S / m). Each wash used three times the mass of the material, and the material was stirred in the ultrapure water for 30 minutes. After each wash, the material was subjected to rotary evaporation in a rotary evaporator. This yielded a Lu-doped high-temperature superconducting raw material precursor. The precursor was then vacuum-dried using an oil bath and sieved to obtain Lu-doped high-temperature superconducting raw material with a particle size of 1-2 μm and the chemical formula Eu. 0.985 Lu 0.015 Ba2Cu3O 7－& .

[0084] Example 6

[0085] This embodiment provides a high-temperature superconducting target, the preparation method of which includes the following steps:

[0086] The Lu-doped high-temperature superconducting raw material prepared in Example 5 was placed in a mold and isostatically pressed at 190 MPa to form a blank. Then, it was placed in a high-temperature furnace filled with 99.999% pure oxygen and fired at 1000°C for 9.5 hours to obtain a cylinder with a diameter of 50.8 mm and a thickness of 35 mm. This cylinder was then cut into sheets with a thickness of 5 mm, thus obtaining the high-temperature superconducting target material.

[0087] Comparative Example 1

[0088] This comparative example provides a material whose preparation method includes the following steps:

[0089] Europium oxide, barium carbonate, and copper oxide were loaded into a plastic bucket in a mass ratio of 23.41:47.8:28.75. The mixture was then mixed at 15 rpm for 8 hours in a three-dimensional mixer. The mixture was then passed through a 100-mesh dry sieve and placed in a tightly packed corundum crucible. It was then sintered in an oxygen furnace at 1000℃ for 6.5 hours. After cooling to 200℃ at a rate of 3℃ / min, the mixture was removed and cooled to room temperature. It was then pulverized using an ultra-micro air jet mill (the air jet mill used 99.999% nitrogen gas at a pressure of 0.3MPa). The mixture was then washed three times with ultrapure water with a resistivity of less than 0.05S / m (each time the amount of ultrapure water used was three times the mass of the material being washed, and the material was stirred in ultrapure water for 30 minutes each time. After each washing, the material was rotary evaporated in a rotary evaporator to obtain a precursor. The precursor was then vacuum dried using an oil bath and sieved to obtain a material with a particle size of 1-2μm.

[0090] Comparative Example 2

[0091] This comparative example provides a target material, the preparation method of which includes the following steps:

[0092] The material prepared in Comparative Example 1 was placed in a mold and isostatically pressed at 190 MPa to form a blank. Then, it was placed in a high-temperature furnace with 99.999% pure oxygen and fired at 1000°C for 9.5 hours to obtain a cylinder with a diameter of 50.8 mm and a thickness of 35 mm. The cylinder was then cut into sheets with a thickness of 5 mm to obtain the target material.

[0093] Comparative Example 3

[0094] This comparative example provides a material whose preparation method includes the following steps:

[0095] The above-mentioned lutetium oxide, barium carbonate, and copper oxide were loaded into a plastic bucket in a mass ratio of 26.47:47.8:28.75. After mixing for 8 hours at 15 rpm in a three-dimensional mixer, the mixture was passed through a 100-mesh dry sieve and then placed in a corundum crucible (tightly packed) and sintered in an oxygen furnace at 1000℃ for 6.5 hours. After cooling to 200℃ at a cooling rate of 3℃ / min, the mixture was removed and cooled to room temperature. Then, it was pulverized using an ultra-micro air jet mill (the gas used in the air jet mill was 99.999% nitrogen at a pressure of 0.3MPa). After that, it was washed three times with ultrapure water with a resistivity of less than 0.05S / m (each time the amount of ultrapure water used was three times the mass of the material being washed, and the material being washed was stirred in ultrapure water for 30 minutes each time. After each washing, it was evaporated in a rotary evaporator to obtain the precursor. The precursor was dried under vacuum by heating in an oil bath and then sieved to obtain a material with a particle size of 1-2μm.

[0096] Comparative Example 4

[0097] This comparative example provides a target material, the preparation method of which includes the following steps:

[0098] The material prepared in Comparative Example 3 was placed in a mold and isostatically pressed at 190 MPa to form a blank. Then, it was placed in a high-temperature furnace with 99.999% pure oxygen and fired at 1000°C for 9.5 hours to obtain a cylinder with a diameter of 50.8 mm and a thickness of 35 mm. The cylinder was then cut into sheets with a thickness of 5 mm to obtain the target material.

[0099] Test case

[0100] 1. The high-temperature superconducting target prepared in Example 2 was used to fabricate a high-temperature superconducting thin film with a thickness of 0.72 μm on the lanthanum manganate layer of the Hastelloy base isolation layer using a PLD process. The superconducting properties of the high-temperature superconducting thin film were tested, and the results were: Ic(77K, 0T) 550 A / 12 mm-width; Ic(77K, 0T) 170 A / 4 mm-width (e.g., ...). Figure 2 As shown), Ic(30K,3T) 595A / 4mm-width. The enhancement factor reaches 3.5 times; the transmission electron microscope image of its thin film is shown below. Figure 3 As shown, it contains 8-9 nm nanopillars that form magnetic flux pinning centers, thus giving the thin film excellent low-temperature high-field performance;

[0101] 2. The high-temperature superconducting target material obtained in Example 4 was used to fabricate a high-temperature superconducting thin film with a thickness of 0.725 μm on the lanthanum manganate layer of the Hastelloy base isolation layer. The superconducting properties of the high-temperature superconducting thin film were tested, and the results were: Ic(77K, 0T) 500 A / 12 mm-width; Ic(77K, 0T) 165 A / 4 mm-width, Ic(30K, 3T) 495 A / 4 mm-width. The improvement factor was 3.0 times.

[0102] 3. The high-temperature superconducting target prepared in Example 6 was used to produce a high-temperature superconducting thin film with a thickness of 0.73 μm on the lanthanum manganate layer of the Hastelloy base isolation layer using the PLD process. The superconducting properties of the high-temperature superconducting thin film were tested, and the test results were: Ic(77K, 0T) 475A / 12mm-width; Ic(77K, 0T) 152A / 4mm-width and Ic(30K, 3T) 433A / 4mm-width, with an improvement factor of 2.8 times.

[0103] 4. The target material prepared in Comparative Example 2 was used to fabricate a high-temperature superconducting thin film with a thickness of 0.742 μm on the lanthanum manganate layer of the Hastelloy base isolation layer using PLD technology. The superconducting properties of the high-temperature superconducting thin film were tested, and the results were: Ic(77K, 0T) 385 / 12mm-width; Ic(77K, 0T) 121.19A / 4mm-width (e.g., ...). Figure 4 As shown), Ic(30K,3T) 324A / 4mm-width. The boost factor is 2.7 times;

[0104] 5. The target material prepared in Comparative Example 4 was used to produce a high-temperature superconducting thin film with a thickness of 0.740 μm on the lanthanum manganate layer of the Hastelloy base isolation layer. The superconducting properties of the high-temperature superconducting thin film were tested, and the results were: Ic(77K, 0T) 360A / 12mm-width; Ic(77K, 0T) 105A / 4mm-width, Ic(30K, 3T) 273A / 4mm-width. The improvement factor was 2.6 times.

[0105] In this invention, by introducing Lu doping into EuBaCuO superconducting material, strip-shaped nanopillars can be generated in the superconducting thin film made from the raw material, thereby creating pinning centers in the film and generating a pinning effect. As a result, the film has good diamagnetic properties, electrical properties and mechanical properties under low temperature and high field conditions.

[0106] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A Lu-doped high temperature superconductor precursor material, characterized in that, The Lu-doped high-temperature superconducting raw material is a Lu-doped EuBaCuO superconducting material; the Lu-doped high-temperature superconducting raw material has a chemical general formula of Eu x Lu y Ba2Cu3O 7－& , wherein 0.75≤x≤0.99, and x+y=1.

2. A method of producing the Lu-doped high-temperature superconducting precursor material according to claim 1, characterized in that The method comprises the following steps: mixing europium source, lutetium source, barium source and copper source to obtain a mixture, sintering the mixture, crushing, washing, drying and sieving the crushed material to obtain the Lu-doped high-temperature superconducting raw material.

3. The method of claim 2, wherein the Lu-doped high-temperature superconducting precursor material is prepared by a process comprising: The europium source is selected from europium oxide; and / or, ​ The lutetium source is selected from lutetium oxide; and / or, The barium source is selected from barium carbonate; and / or The copper source is selected from copper oxide.

4. The method of producing a Lu-doped high-temperature superconducting precursor material according to claim 2 or 3, characterized in that, The purity of the europium source is greater than or equal to 99.999%; and the particle size of the europium source is 1-1.2 μm; and / or, The purity of the lutetium source is greater than or equal to 99.999%; and the particle size of the lutetium source is 1-1.2 μm; and / or, The purity of the barium source is greater than or equal to 99.995%; and the particle size of the barium source is 1-1.5 μm; and / or, The purity of the copper source is greater than or equal to 99.999%; and the particle size of the barium source is 0.5-1 μm.

5. The method of producing a Lu-doped high-temperature superconducting precursor material according to claim 2 or 3, characterized in that, The preparation method of the europium source comprises the following steps: airflow milling, washing, rotary evaporation and sieving of the initial europium source to obtain the europium source. The pressure of the airflow mill is 0.15-0.25 MPa; the gas of the airflow mill is nitrogen with a purity greater than or equal to 99.999%; and the conductivity of the water used in the washing process is less than or equal to 0.05 S / m; and / or, The preparation method of the lutetium source comprises the following steps: airflow milling, washing, rotary evaporation and sieving of the initial lutetium source to obtain the lutetium source. The pressure of the airflow mill is 0.15-0.25 MPa; the gas of the airflow mill is nitrogen with a purity greater than or equal to 99.999%; and the conductivity of the water used in the washing process is less than or equal to 0.05 S / m; and / or, The preparation method of the barium source comprises the following steps: airflow milling, washing, rotary evaporation and sieving of the initial barium source to obtain the barium source. The pressure of the airflow mill is 0.15-0.25 MPa; the gas of the airflow mill is nitrogen with a purity greater than or equal to 99.999%; and the conductivity of the water used in the washing process is less than or equal to 0.05 S / m; and / or, The preparation method of the copper source comprises the following steps: airflow milling, washing, rotary evaporation and sieving of the initial copper source to obtain the copper source. The pressure of the airflow mill is 0.15-0.25 MPa; the gas of the airflow mill is nitrogen with a purity greater than or equal to 99.999%; and the conductivity of the water used in the washing process is less than or equal to 0.05 S / m.

6. The method of producing a Lu-doped high-temperature superconducting precursor material according to claim 2 or 3, characterized in that, In terms of the metal stoichiometric ratio, the molar ratio of europium, lutetium, barium and copper in the mixture is (0.75-0.99):(0.01-0.25):(1.9-2.1):(2.9-3.1); and / or, The sintering temperature of the mixture is 980-1010 ℃, the sintering time is 6-7 h, and the sintering atmosphere is oxygen; and / or, The airflow mill is used for crushing, wherein the pressure of the airflow mill is 0.25-0.35 MPa; and the gas of the airflow mill is nitrogen with a purity greater than or equal to 99.999%; and / or, The conductivity of the water used in the washing process is less than or equal to 0.05 S / m.

7. A high temperature superconducting target material, characterized by, The Lu-doped high-temperature superconducting raw material of claim 1, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method of any one of claims 2-6.

8. The method of claim 7, wherein the high temperature superconducting target is prepared by the steps of: The method comprises the following steps: pressing the Lu-doped high-temperature superconducting raw material of claim 1, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method of any one of claims 2-6 to obtain a blank, and sintering and slicing the blank to obtain the high-temperature superconducting target material. ​ 9. The method of claim 8, wherein the method further comprises the step of: The pressing is isostatic pressing, and the pressing pressure is 180-200 MPa; and / or The sintering temperature is 985-1010 ℃, the sintering time is 8-10 h, and the sintering atmosphere is oxygen with a purity greater than or equal to 99.999%; and / or The high-temperature superconducting target material obtained by slicing is a round sheet, and the diameter of the round sheet is 50-60 mm and the thickness is 5 mm.

10. A superconducting thin film, characterized by, The material of the superconducting thin film is selected from the Lu-doped high-temperature superconducting raw material of claim 1, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method of any one of claims 2-6, or the high-temperature superconducting target material of claim 7, or the high-temperature superconducting target material prepared by the preparation method of claim 8 or 9.

11. The method of making a superconducting thin film of claim 10, wherein, The method comprises the following steps: depositing the Lu-doped high-temperature superconducting raw material of claim 1, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method of any one of claims 2-6, or the high-temperature superconducting target material of claim 7, or the high-temperature superconducting target material prepared by the preparation method of claim 8 or 9 on a substrate to obtain the superconducting thin film.

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