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

Abstract

The invention 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 invention provides a Lu-doped high-temperature superconducting raw material. The Lu-doped high-temperature superconducting raw material is a Lu-doped EuBaCuO superconducting material. According to the invention, Lu doping is introduced into the EuBaCuO superconducting material, so that the target material prepared from the raw material can generate strip-shaped nano columns in the formed superconducting thin film, a pinning center appears in the thin film, a pinning effect is generated, and the thin film has relatively good diamagnetic performance, electrical performance and mechanical performance in a low-temperature high field.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting materials, and in particular to a Lu-doped high-temperature superconducting raw material and a preparation method and application thereof. Background Art

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

[0003] In the related art, RBa2Cu3O is produced 7-δ There are many superconducting thin film process routes, such as pulsed laser deposition (PLD), metal organic deposition (MOD), chemical vapor deposition (MOCVD) and reactive sputtering epitaxy (RCE). Fujikura of Japan, Superox of Russia, Bruker of Germany and Shanghai Superconducting Technology (SST) all use IBAD / PLD composite technology to produce RBa2Cu3O 7-δ Superconducting tape has a high critical current at 77K and 0T, but poor anti-magnetism at low temperature and high field, resulting in weakened electrical properties and a low current enhancement factor. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the RBa2Cu3O 7-δ Superconducting thin film materials have poor anti-magnetism under low temperature and high field, which leads to weakened electrical properties and low current enhancement factor. Therefore, a Lu-doped high-temperature superconducting raw material and a preparation method and use thereof are provided.

[0005] The 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 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 of the Lu-doped high-temperature superconducting raw material include a europium source, a lutetium source, a barium source and a 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 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 a europium source, a lutetium source, a barium source and a copper source to obtain a mixture, sintering and crushing the mixture, washing, drying and sieving the crushed material to obtain the Lu-doped high-temperature superconducting raw material.

[0011] Optionally, the mixing process is to mix the 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, a cooling process is further included after sintering, wherein the cooling process is to reduce the temperature to 150-250° C. at a cooling rate of 3-4° C. / min after sintering, and then naturally cool in an environment of 20-40° C.

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

[0015] Optionally, the drying process is heated 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 purity of the lutetium source is greater than or equal to 99.999%; the particle size of the lutetium source is 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 0.5-1 μm.

[0024] Preferably, the preparation method of the europium source is to crush the initial europium source by jet milling, washing, rotary evaporation and sieving, so as to obtain the europium source;

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

[0026] The preparation method of the lutetium source comprises the steps of jet milling, crushing, washing, rotary evaporation and sieving the initial lutetium source to obtain the lutetium source;

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

[0028] The preparation method of the barium source is to jet mill the initial barium source, wash, rotary evaporate and sieve, so as to obtain the barium source;

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

[0030] The preparation method of the copper source is to grind the initial copper source by air flow milling, washing, rotary evaporation and screening, so as to obtain the copper source;

[0031] 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 detergent used in washing is water with an electrical 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 the present application are all commercially available high-grade pure products (purity of 99.8-99.99%), and the particle size of the products is micron-level.

[0033] Optionally, the air flow mill in the method for preparing the europium source, the method for preparing the lutetium source, the method for preparing the barium source, and the method for preparing the copper source is selected from an ultrafine air flow 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 is to use detergent to wash three times, and the mass ratio of detergent to washed object in each washing process is (2.5-3.5):1.

[0035] In the present application, the material is crushed by air flow milling. Compared with medium ball milling, it can use air flow to open the particles whose grains are adhered due to high-temperature solid-phase reaction, thereby maintaining the original growth morphology of the product and avoiding the destruction of the original crystal form and the introduction of impurities by medium ball milling.

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

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

[0038] The pulverizing process uses a jet mill, wherein the pressure of the jet mill is 0.25-0.35 MPa; the gas of the 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 less than or equal to 0.05S / m.

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

[0041] In the present application, the sintering atmosphere is oxygen, so that the oxygen component can be continuously replenished to ensure the reaction in an oxygen-rich atmosphere, thereby improving the electrical properties, antimagnetic properties and mechanical properties of the Lu-doped high-temperature superconducting raw material.

[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 above-mentioned high-temperature superconducting target material, comprising the following steps: pressing the above-mentioned Lu-doped high-temperature superconducting raw material, or the Lu-doped high-temperature superconducting raw material prepared by the above-mentioned 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°C, the sintering time is 8-10h; the sintering atmosphere is oxygen, wherein the oxygen purity is greater than or equal to 99.999%; and / or,

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

[0047] Optionally, the process of pressing to obtain a 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 film, the material of which 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 above-mentioned preparation method, or the above-mentioned high-temperature superconducting target material, or the high-temperature superconducting target material prepared by the above-mentioned preparation method.

[0050] The present invention also provides a method for preparing the superconducting 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 above-mentioned preparation method, or the above-mentioned high-temperature superconducting target material, or the high-temperature superconducting target material prepared by the above-mentioned preparation method on a substrate to obtain the superconducting film.

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

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

[0053] The 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 the present invention, Lu doping is introduced into the EuBaCuO superconducting material, so that the target material made of the raw material can generate strip nanocolumns (with a diameter of about 7-10nm) in the formed superconducting film, so that pinning centers appear in the film, generating a pinning effect, so that the film has good antimagnetic properties, electrical properties and mechanical properties under low temperature and high field;

[0055] Furthermore, the preparation method provided by the present invention provides a processing process for high-grade pure raw materials, thereby obtaining raw materials with higher purity, thereby improving the purity of the final Lu-doped high-temperature superconducting raw materials, and further improving the electrical properties of the final prepared film. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

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

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

[0059] Figure 3 is a transmission electron microscope image of a high-temperature superconducting film prepared from a high-temperature superconducting target material prepared in Example 2 of the present invention;

[0060] Figure 4 This is a relationship diagram between current and voltage of a high-temperature superconducting film prepared from a high-temperature superconducting target material prepared in Comparative Example 2 of the present invention after being cut and tested. DETAILED DESCRIPTION

[0061] The following examples are provided to further understand the present invention better, are not limited to the best mode, and are not intended to limit the content and scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the enlightenment of the present invention or by combining the features of the present invention with other prior arts, all falls within the protection scope of the present invention. If no specific experimental steps or conditions are indicated in the examples, the operation or conditions of the conventional experimental steps described in the literature in this area can be carried out. If the manufacturer is not indicated for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0062] The initial europium oxide, initial lutetium oxide, initial barium carbonate, and initial copper oxide used in the examples are all commercially available high-grade pure products (purity of 99.8-99.99%), and the particle size of the products is micron-level.

[0063] The preparation of europium oxide comprises the following steps: crushing the initial europium oxide by ultrafine air flow milling (the gas used in the air flow milling is 99.999% nitrogen and the gas pressure is 0.2MPa), then washing three times with ultrapure water having a resistivity of less than 0.05S / m (the amount of ultrapure water used each time is three times the mass of the initial europium oxide), then rotary evaporating in a rotary evaporator, and sieving to obtain europium oxide with a particle size of 1-1.2μm and a purity greater than 99.999%;

[0064] The preparation of lutetium oxide comprises the following steps: crushing the initial lutetium oxide by ultrafine air flow milling (the gas used by the air flow milling is 99.999% nitrogen and the gas pressure is 0.2MPa), then washing three times with ultrapure water having a resistivity of less than 0.05S / m (the amount of ultrapure water used each time is three times the mass of the initial lutetium oxide), then rotary evaporating in a rotary evaporator, and sieving to obtain lutetium oxide with a particle size of 1-1.2μm and a purity greater than 99.999%;

[0065] The preparation of barium carbonate comprises the following steps: crushing the initial barium carbonate by ultrafine airflow mill (the gas used in the airflow mill is 99.999% nitrogen and the gas pressure is 0.2MPa), then washing three times with ultrapure water having a resistivity of less than 0.05S / m (the amount of ultrapure water used each time is three times the mass of the initial barium carbonate), then rotary evaporating in a rotary evaporator, and sieving to obtain barium carbonate with a particle size of 1-1.5μm and a purity greater than 99.995%;

[0066] The preparation of copper oxide comprises the following steps: crushing the initial copper oxide by ultrafine airflow milling (the gas used in the airflow milling is 99.999% nitrogen and the gas pressure is 0.2MPa), then washing three times with ultrapure water having a resistivity of less than 0.05S / m (the amount of ultrapure water used each time is three times the mass of the initial copper oxide), then rotary evaporating in a rotary evaporator, and sieving to obtain copper oxide with a particle size of 0.5-1μm and a purity greater than 99.999%;

[0067] Example 1

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

[0069] The europium oxide, lutetium oxide, barium carbonate and copper oxide were put into a plastic barrel in a mass ratio of 21.36:0.37:48.77:29.51, mixed on a three-dimensional mixer at 15 rpm for 8 h, and then passed through a 100-mesh dry sieve. The mixture was then placed in a corundum crucible (tightly packed) and sintered in an oxygen furnace at 1000°C for 6.5 h. The mixture was then cooled to 200°C at a rate of 3°C / min, taken out and cooled at room temperature, and then pulverized using an ultrafine airflow mill (the gas used in the airflow mill is 99.999% nitrogen, and the gas pressure is 200°C). The raw material precursor is Lu-doped with a high temperature superconducting material and the raw material precursor is vacuum dried by heating in an oil bath and then sieved to obtain a Lu-doped high temperature superconducting raw material with a particle size of 1-2 μm, and the chemical formula is Eu 0.985 Lu 0.015 Ba2Cu3O 7－& .

[0070] The Lu-doped high-temperature superconducting raw material was prepared by inductively coupled plasma testing, and its purity was 99.995%.

[0071] Example 2

[0072] This embodiment provides a high temperature superconducting target material, and the preparation method includes the following steps:

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

[0074] Example 3

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

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

[0077] The Lu-doped high-temperature superconducting raw material was prepared by inductively coupled plasma testing, and its purity was 99.995%.

[0078] Example 4

[0079] This embodiment provides a high temperature superconducting target material, and the preparation method includes the following steps:

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

[0081] Example 5

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

[0083] Initial europium oxide, initial lutetium oxide, initial barium carbonate, and initial copper oxide were placed in a plastic barrel at a mass ratio of 21.36:0.37:48.77:29.51, mixed on a three-dimensional mixer at 15 rpm for 8 h, passed through a 100-mesh dry sieve, and then placed in a corundum crucible (tightly packed) and sintered in an oxygen furnace at 1000°C for 6.5 h, then cooled to 200°C at a rate of 3°C / min, taken out and cooled at room temperature, and then pulverized using an ultrafine airflow mill (the gas used in the airflow mill is 99.999% nitrogen, the gas The raw material was crushed by ultrapure water with a resistivity of less than 0.05S / m, and then washed three times with ultrapure water having a resistivity of less than 0.05S / m (the amount of ultrapure water used each time was three times the mass of the washed material, and the washed material was stirred in the ultrapure water for 30 minutes each time, and rotary evaporation was performed in a rotary evaporator after each washing) to obtain a Lu-doped high-temperature superconducting raw material precursor, and the Lu-doped high-temperature superconducting raw material precursor was vacuum dried by heating in an oil bath, and then sieved to obtain a Lu-doped high-temperature superconducting raw material with a particle size of 1-2μm, whose chemical formula is Eu 0.985 Lu 0.015 Ba2Cu3O 7－& .

[0084] Example 6

[0085] This embodiment provides a high temperature superconducting target material, and the preparation method includes the following steps:

[0086] The Lu-doped high-temperature superconducting raw material prepared in Example 5 was placed in a mold, and was formed into a blank by isostatic pressing at a pressure of 190 MPa. Then, it was fired at 1000° C. for 9.5 h in a high-temperature furnace with 99.999% pure oxygen to obtain a column with a diameter of 50.8 mm and a thickness of 35 mm. The column was cut into sheets with a thickness of 5 mm to obtain the high-temperature superconducting target.

[0087] Comparative Example 1

[0088] This comparative example provides a material, and the preparation method comprises the following steps:

[0089] The europium oxide, barium carbonate and copper oxide are put into a plastic barrel according to the mass ratio of 23.41:47.8:28.75, and mixed on a three-dimensional mixer at 15 rpm for 8 hours, and then the mixture is passed through a 100-mesh dry sieve, and then placed in a corundum crucible (tightly packed) and sintered in an oxygen furnace at 1000°C for 6.5 hours, and then cooled to 200°C at a cooling rate of 3°C / min, taken out and cooled at room temperature, and then crushed using an ultrafine airflow mill (the gas used in the airflow mill is 99.999% nitrogen, and the gas pressure is 0.3MPa), and then washed three times with ultrapure water with a resistivity of less than 0.05S / m (the amount of ultrapure water used each time is three times the mass of the washed material, and the washed material is stirred in ultrapure water for 30 minutes each time, and rotary evaporated in a rotary evaporator after each washing) to obtain a precursor, and the precursor is vacuum dried by heating in an oil bath, and then sieved to obtain a material with a particle size of 1-2μm;

[0090] Comparative Example 2

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

[0092] The material prepared in Comparative Example 1 was placed in a mold and formed into a blank by isostatic pressing at a pressure of 190 MPa. It was then fired at 1000°C for 9.5 hours in a high-temperature furnace filled with 99.999% pure oxygen to obtain a cylinder with a diameter of 50.8 mm and a thickness of 35 mm. The cylinder was 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, and the preparation method comprises the following steps:

[0095] The above-mentioned lutetium oxide, barium carbonate and copper oxide are put into a plastic barrel according to the mass ratio of 26.47:47.8:28.75, and mixed on a three-dimensional mixer at 15 rpm for 8 hours, and then the mixture is passed through a 100-mesh dry sieve, and then placed in a corundum crucible (tightly packed) and sintered in an oxygen furnace at 1000°C for 6.5 hours, and then cooled to 200°C at a cooling rate of 3°C / min, taken out and cooled at room temperature, and then crushed using an ultrafine air flow mill (the gas used in the air flow mill is 99.999% nitrogen, and the gas pressure is 0.3MPa), and then washed three times with ultrapure water with a resistivity of less than 0.05S / m (the amount of ultrapure water used each time is three times the mass of the washed material, and the washed material is stirred in ultrapure water for 30 minutes each time, and rotary evaporated in a rotary evaporator after each washing) to obtain a precursor, and the precursor is vacuum dried 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, and the preparation method includes the following steps:

[0098] The material prepared in Comparative Example 3 was placed in a mold and formed into a blank by isostatic pressing at a pressure of 190 MPa. It was then fired at 1000°C for 9.5 hours in a high-temperature furnace filled with 99.999% pure oxygen to obtain a cylinder with a diameter of 50.8 mm and a thickness of 35 mm. The cylinder was 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 placed on the lanthanum manganate layer of the Hastelloy base band isolation layer, and a high-temperature superconducting film with a thickness of 0.72 μm was produced by PLD process; the superconducting performance of the high-temperature superconducting film was tested, and the test results were: Ic (77K, 0T) 550A / 12mm-width; Ic (77K, 0T) 170A / 4mm-width (such as Figure 2 As shown), Ic (30K, 3T) 595A / 4mm-width. The improvement factor is 3.5 times; the transmission electron microscope image of the film is as follows Figure 3 As shown, it contains 8-9nm nanopillars, which form magnetic flux pinning centers, so that the low-temperature and high-field performance of the film is excellent;

[0101] 2. The high-temperature superconducting target prepared in Example 4 was placed on the lanthanum manganate layer of the Hastelloy base band isolation layer, and a high-temperature superconducting film with a thickness of 0.725 μm was produced by PLD process; the superconducting performance of the high-temperature superconducting film was tested, and the test results were: Ic (77K, 0T) 500A / 12mm-width; Ic (77K, 0T) 165A / 4mm-width, Ic (30K, 3T) 495A / 4mm-width. The improvement factor was 3.0 times;

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

[0103] 4. The target prepared in Comparative Example 2 was placed on the lanthanum manganate layer of the Hastelloy base band isolation layer, and a high-temperature superconducting film with a thickness of 0.742 μm was produced by PLD process; the superconducting properties of the high-temperature superconducting film were tested, and the test results were: Ic (77K, 0T) 385 / 12mm-width; Ic (77K, 0T) 121.19A / 4mm-width (as shown in FIG. Figure 4 As shown), Ic (30K, 3T) 324A / 4mm-width. The improvement factor is 2.7 times;

[0104] 5. The target prepared in Comparative Example 4 was placed on the lanthanum manganate layer of the Hastelloy base band isolation layer, and a high-temperature superconducting film with a thickness of 0.740 μm was produced using the PLD process; the superconducting properties of the high-temperature superconducting film were tested, and the test 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 the present invention, Lu doping is introduced into the EuBaCuO superconducting material, so that the target material made of the raw materials can generate strip nanocolumns in the formed superconducting film, so that pinning centers appear in the film, generating a pinning effect, so that the film has better antimagnetic properties, electrical properties and mechanical properties under low temperature and high field.

[0106] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A Lu-doped high-temperature superconducting raw material, characterized in that: The Lu-doped high-temperature superconducting raw material is a Lu-doped EuBaCuO superconducting material.

2. The Lu-doped high-temperature superconducting raw material according to claim 1, characterized in that: 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.

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

4. The method for preparing Lu-doped high-temperature superconducting raw materials according to claim 3, characterized in that: 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.

5. The method for preparing the Lu-doped high-temperature superconducting raw material according to claim 3 or 4, characterized in that: 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, The purity of the lutetium source is greater than or equal to 99.999%; 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%; 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%; the particle size of the barium source is 0.5-1 μm.

6. The method for preparing the Lu-doped high-temperature superconducting raw material according to any one of claims 3 to 5, characterized in that: The preparation method of the europium source comprises jet milling, crushing, washing, rotary evaporation and sieving the initial europium source to obtain the europium source; The pressure of the jet mill is 0.15-0.25 MPa; the gas of the jet mill is nitrogen with a purity greater than or equal to 99.999%; the detergent used in the washing is water with a conductivity less than or equal to 0.05 S / m; and / or, The preparation method of the lutetium source comprises the steps of jet milling, crushing, washing, rotary evaporation and sieving the initial lutetium source to obtain the lutetium source; The pressure of the jet mill is 0.15-0.25 MPa; the gas of the jet mill is nitrogen with a purity greater than or equal to 99.999%; the detergent used in the washing is water with a conductivity less than or equal to 0.05 S / m; and / or, The preparation method of the barium source is to jet mill the initial barium source, wash, rotary evaporate and sieve, so as to obtain the barium source; The pressure of the jet mill is 0.15-0.25 MPa; the gas of the jet mill is nitrogen with a purity greater than or equal to 99.999%; the detergent used in the washing is water with a conductivity less than or equal to 0.05 S / m; and / or, The preparation method of the copper source is to grind the initial copper source by air flow milling, washing, rotary evaporation and screening, so as 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 detergent used in washing is water with an electrical conductivity less than or equal to 0.05 S / m.

7. The method for preparing the Lu-doped high-temperature superconducting raw material according to any one of claims 3 to 6, characterized in that: In terms of metal stoichiometric ratio, the molar ratio of europium, lutetium, barium and copper elements added to the mixture is (0.75-0.99): (0.01-0.25): (1.9-2.1): (2.9-3.1); and / or, The mixed material is sintered at a temperature of 980-1010°C for 6-7 hours in an oxygen atmosphere; and / or, The pulverizing process uses a jet mill, wherein the pressure of the jet mill is 0.25-0.35 MPa; the gas of the jet mill is nitrogen with a purity greater than or equal to 99.999%; and / or, The detergent used in the washing process of the crushed material is water with an electrical conductivity less than or equal to 0.05S / m.

8. A high temperature superconducting target material, characterized in that: The invention relates to a Lu-doped high-temperature superconducting raw material comprising the Lu-doped high-temperature superconducting raw material according to claim 1 or 2, or a Lu-doped high-temperature superconducting raw material prepared by the method for preparing the Lu-doped high-temperature superconducting raw material according to any one of claims 3 to 7.

9. The method for preparing a high temperature superconducting target material according to claim 8, characterized in that: The method comprises the following steps: pressing the Lu-doped high-temperature superconducting raw material according to claim 1 or 2, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method of the Lu-doped high-temperature superconducting raw material according to any one of claims 3 to 7 to obtain a blank, sintering and slicing the blank to obtain the high-temperature superconducting target material.

10. The method for preparing a high temperature superconducting target material according to claim 9, characterized in that: The pressing is isostatic pressing; the pressing pressure is 180-200 MPa; and / or, The sintering temperature is 985-1010°C, the sintering time is 8-10 hours, and the sintering atmosphere is oxygen, wherein the oxygen purity is greater than or equal to 99.999%; and / or, The high-temperature superconducting target material obtained by slicing is a disc; the diameter of the disc is 50-60 mm and the thickness is 5 mm.

11. A superconducting film, characterized in that: The material of the superconducting film is selected from the Lu-doped high-temperature superconducting raw material according to claim 1 or 2, or the Lu-doped high-temperature superconducting raw material prepared by the preparation method of the Lu-doped high-temperature superconducting raw material according to any one of claims 3 to 7, or the high-temperature superconducting target material according to claim 8, or the high-temperature superconducting target material prepared by the preparation method of the high-temperature superconducting target material according to claim 9 or 10.

12. The method for preparing a superconducting thin film according to claim 11, characterized in that: The method comprises the following steps: depositing the Lu-doped high-temperature superconducting raw material according to claim 1 or 2, or the Lu-doped high-temperature superconducting raw material prepared by the method for preparing the Lu-doped high-temperature superconducting raw material according to any one of claims 3 to 7, or the high-temperature superconducting target material according to claim 8, or the high-temperature superconducting target material prepared by the method for preparing the high-temperature superconducting target material according to claim 9 or 10 on a substrate to obtain the superconducting film.

Images