Method for preparing high-performance REBCO high-temperature superconducting bulk material based on layered precursor embryo

Abstract

The present invention provides a method for preparing a high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo, which relates to the technical field of high-temperature superconducting materials, including: obtaining a preset molar ratio of original chemicals, and preparing an original powder combination by a solid phase sintering method; preparing a precursor powder combination by mixing the original powder combination; using the precursor powder combination to press to obtain a combined precursor embryo and a buffer layer; processing the REBCO original seed crystal, the combined precursor embryo and the buffer layer based on a preset top seed crystal melt texturing method to obtain an initial REBCO high-temperature superconducting bulk material; and heat treating the initial REBCO high-temperature superconducting bulk material to obtain a final REBCO high-temperature superconducting bulk material. The present invention realizes the redistribution of refined particles in the solid solution by layered preparation and forming a combined precursor embryo, thereby improving the superconducting performance of the bulk material while maintaining a low porosity, thereby enhancing the overall performance of the material.

Description

Technical Field

[0001] The present invention relates to the technical field of high-temperature superconducting materials, and in particular to a method for preparing a high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo. Background Art

[0002] In the field of superconducting materials, REBCO (RE stands for light rare earth elements, such as Y, Gd, Sm, Nd, etc.) high-temperature superconducting bulk materials have attracted extensive attention and favor in the fields of energy, transportation, and medical treatment due to their "three high" characteristics: high superconducting transition temperature, high critical current density, and high critical magnetic field. Since its advent, scientists have conducted in-depth research and exploration on the preparation methods of REBCO high-temperature superconducting bulk materials in order to continuously improve the performance of the materials. However, the current preparation technology faces significant challenges. During the growth process of REBCO superconducting bulk materials, RE211 (RE 2 BaCuOx) particles are embedded in RE123 (REBa 2 Cu 3 O 7-δ ) matrix, forming pinning centers that play a decisive role in superconducting performance. In order to improve the superconducting performance of superconducting bulk materials, RE211 particles need to be refined and evenly distributed. However, the existing precursor powder combination method (MPP), although it can refine the particle size of RE211 particles and optimize their distribution, introduces additional oxygen, resulting in severe pore distribution inside the final sample, thereby deteriorating the mechanical properties of the superconducting bulk material and affecting its reliability in practical applications.

[0003] Based on the shortcomings of the existing technology, there is an urgent need for a method for preparing high-performance REBCO high-temperature superconducting bulk materials based on a layered precursor embryo. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing high-performance REBCO high-temperature superconducting bulk materials based on a layered precursor embryo to improve the above problems. In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0005] The present application provides a method for preparing a high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo, comprising:

[0006] Obtaining original drugs of a preset molar ratio, and preparing an original powder combination by a solid phase sintering method;

[0007] A precursor powder combination is prepared by mixing the original powder combination, wherein the precursor powder combination includes a first precursor powder, a second precursor powder and a buffer layer powder, and the refined particle ratio of the second precursor powder is greater than the refined particle ratio of the first precursor powder;

[0008] Based on a preset embryo production method, the precursor powder is combined and pressed to obtain a combined precursor embryo and a buffer layer, wherein the combined precursor embryo includes a second precursor embryo arranged at the bottom and a first precursor embryo placed coaxially and colaterally above the second precursor embryo;

[0009] Based on a preset top seed crystal melt texturing method, the REBCO original seed crystal, the combined precursor embryo and the buffer layer are processed to obtain an initial REBCO high temperature superconducting bulk material;

[0010] The initial REBCO high-temperature superconducting bulk material is subjected to heat treatment to obtain a final REBCO high-temperature superconducting bulk material.

[0011] The beneficial effects of the present invention are:

[0012] The present invention optimizes the process by layered preparation and forming a combined precursor embryo, realizes the redistribution of refined particles within the solid solution, maintains the porosity at about 18% while improving the superconducting performance of the bulk material, and enhances the overall performance of the material.

[0013] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or be understood by implementing the embodiments of the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 This is a flow chart of a method for preparing a high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo as described in an embodiment of the present application;

[0016] Figure 2 This is a graph showing the porosity and average number of pores per unit area of ​​different samples. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0019] like Figure 1 As shown, this embodiment provides a method for preparing a high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo, wherein RE in the REBCO high-temperature superconducting bulk material is selected from rare earth elements such as Y, Gd, Sm, and Nd. The method includes steps S100, S200, S300, S400, and S500.

[0020] Step S100, obtaining original drugs of a preset molar ratio, and preparing an original powder combination by a solid phase sintering method;

[0021] It should be noted that step S100 includes step S110, step S120 and step S130.

[0022] Step S110: According to RE 2 O 3 :BaCO 3 :CuO=Three portions of the original drug were weighed in molar ratios of 1:4:6, 1:1:1 and 0:2:3;

[0023] Step S120, mixing the three original medicines respectively to prepare RE123 original powder, RE211 original powder and RE023 original powder;

[0024] Step S130, preparing RE123 original powder, RE211 original powder and RE023 original powder by solid phase sintering method to obtain purified RE123 powder, RE211 powder and RE023 powder.

[0025] It is understood that the solid phase sintering method is a method of heating powder materials to their solid phase reaction temperature so that they are combined with each other without melting to form a dense material. For the preparation of REBCO superconducting bulk materials, the solid phase sintering method helps to improve the purity and crystallinity of the original powder, thereby optimizing its subsequent processing and performance. It should be noted that step S130 includes step S131 and step S132.

[0026] Step S131, sintering the RE123 raw powder in an air environment at 920° C. for 48 hours, sintering the RE211 raw powder in an air environment at 930° C. for 48 hours, and sintering the RE023 raw powder in an air environment at 880° C. for 48 hours to obtain sintered RE123 powder blocks, RE211 powder blocks, and RE023 powder blocks;

[0027] Step S132: Grind and sinter the sintered RE123 powder block, RE211 powder block and RE023 powder block, repeat three times to obtain purified RE123 powder, RE211 powder and RE023 powder.

[0028] Step S200, preparing a precursor powder combination by mixing the original powder combination, wherein the precursor powder combination includes a first precursor powder, a second precursor powder and a buffer layer powder, and the refined particle ratio of the second precursor powder is greater than the refined particle ratio of the first precursor powder;

[0029] It should be noted that, however, the first precursor powder is composed of RE123 and RE211, which is a conventional precursor powder formula (CPP), and its particle size is relatively large. The second precursor powder is composed of RE200 and RE023, which is a refined precursor split formula (MPP). It should be noted that step S200 includes step S210, step S220 and step S230.

[0030] Step S210: weigh and mix RE123 powder and RE211 powder in a molar ratio of 1:0.35, and add 1 wt% CeO 2 The powders are mixed to obtain a first precursor powder;

[0031] Step S220: weigh and mix RE200 powder and RE023 powder in a molar ratio of 0.72:1, and add 1 wt% CeO 2 The powders are mixed to obtain a second precursor powder;

[0032] Step S230: weigh and mix RE123 powder and RE211 powder in a molar ratio of 1:0.4, and add 1 wt% CeO 2The powders are mixed to obtain a buffer layer powder.

[0033] Step S300: Based on a preset embryo production method, a combined precursor embryo and a buffer layer are obtained by combining and pressing the precursor powders, wherein the combined precursor embryo includes a second precursor embryo arranged at the bottom and a first precursor embryo placed coaxially and colaterally above the second precursor embryo;

[0034] It is understandable that the hierarchical design of the first precursor embryo and the second precursor embryo is to optimize the microstructure of the superconducting block. The second precursor embryo at the bottom, because it contains more refined particles, can form more pinning centers and improve the superconducting performance of the lower area. The first precursor embryo on the upper layer plays a role in providing mechanical strength. It should be noted that step S300 includes step S310, step S320, step S330 and step S340.

[0035] Step S310, weighing 20 g of the first precursor powder and putting it into a square mold with a side length of 30 mm for pressurization to obtain a first precursor embryo;

[0036] Step S320, weighing 20 g of the second precursor powder and putting it into a square mold with a side length of 30 mm for pressurization to obtain a second precursor embryo;

[0037] Step S330, placing the first precursor embryo coaxially and coaxially on the second precursor embryo to obtain a combined precursor embryo;

[0038] Step S340, weigh 0.25 g of the buffer layer powder and put it into a cylindrical mold with a diameter of 6 mm for pressurization to obtain the buffer layer.

[0039] Step S400, processing the REBCO original seed crystal, the combined precursor embryo and the buffer layer based on a preset top seed crystal melt texturing method to obtain an initial REBCO high temperature superconducting bulk material;

[0040] It is understood that the top seed melt texturing method (TSMG) is a method for preparing high-performance REBCO high-temperature superconducting bulk materials by seed-induced growth technology. By controlling the melting temperature and the cooling rate, the seed crystal can induce the lower layer of the combined precursor embryo to form a textured superconducting phase. It should be noted that step S400 includes step S410 and step S420.

[0041] Step S410, inserting a buffer layer between the REBCO original seed crystal and the combined precursor embryo body to obtain a coaxial combined structure, wherein the coaxial combined structure includes the REBCO original seed crystal, the buffer layer and the combined precursor embryo body coaxially from top to bottom;

[0042] It is understandable that the coaxial combination structure ensures close contact between the seed crystal, the buffer layer and the precursor embryo, which helps to induce uniform heat conduction and chemical component diffusion during the growth process. It should be noted that step S410 includes step S411 and step S412.

[0043] Step S411, selecting a 3 mm×3 mm×3 mm REBCO original seed crystal with a smooth base surface, and polishing the base surface of the REBCO original seed crystal to obtain a processed REBCO original seed crystal;

[0044] Step S412, align the central axis of the processed REBCO original seed crystal perpendicular to the ground with the central axis of the punch layer and the central axis of the combined precursor embryo respectively, and place the REBCO original seed crystal between the buffer layer and the combined precursor embryo to obtain a coaxial combined structure.

[0045] Step S420: placing the combined structure on an alumina ceramic plate, and placing it in a high-temperature furnace in an air atmosphere for texture growth, to obtain an initial REBCO high-temperature superconducting bulk material induced by REBCO original seed crystal growth.

[0046] It is understandable that in this step, a high-quality superconducting phase structure is formed by melt texture growth and the crystal orientation guiding effect of the REBCO original seed crystal is utilized to improve the superconducting performance. It should be noted that step S420 includes step S421, step S422 and step S423.

[0047] Step S421, the temperature in the high temperature furnace starts from room temperature, rises to 900°C after 1 hour, and is kept at this temperature for 3 hours, and then continues to be heated for 1 hour, the temperature in the high temperature furnace rises to 1055°C, and is kept at this temperature for 1 hour;

[0048] Step S422, lowering the furnace temperature to 1005° C. within 30 minutes, and then lowering the furnace temperature at a cooling rate of 0.2 K / h to 0.4 K / h, so that the REBCO original seed crystals in the furnace induce the combined precursor embryo to grow for 100 hours;

[0049] It should be noted that the above temperature program is suitable for preparing YBCO superconducting bulk material using a top seed crystal melt texturing method, wherein the top seed crystal is a SmBCO seed crystal.

[0050] In other embodiments, such as preparing GdBCO superconducting bulk by melt texturing with a top seed crystal (SmBCO seed crystal), the temperature program for texture growth is as follows: starting from room temperature, heating to 900°C over 1 hour and keeping warm for 3 hours; then heating to a maximum temperature (Tm) of 1055°C over 1 hour and keeping warm for 1 hour; quickly lowering the furnace temperature to 1045°C within 10 minutes; then lowering the furnace temperature at a cooling rate of 0.3K / h to 0.6K / h, so that the GdBCO sample in the furnace grows slowly for 100 hours; after the sample growth is completed, quickly lowering the furnace temperature to room temperature over 3 hours to obtain a GdBCO high-temperature superconducting bulk.

[0051] Similarly, the SmBCO superconducting bulk was prepared by the top seed crystal (NdBCO seed crystal) melt texturing method, and the temperature program for texture growth was as follows: starting from room temperature, the temperature was raised to 900°C over 1 hour and kept at this temperature for 3 hours; then the temperature was raised to the maximum temperature (Tm) of 1075°C over 1 hour and kept at this temperature for 1 hour; the furnace temperature was quickly lowered to 1060°C within 10 minutes; then the furnace temperature was lowered at a cooling rate of 0.3K / h to 0.6K / h, so that the SmBCO sample in the furnace grew slowly for 100 hours; after the sample growth was completed, the furnace temperature was quickly lowered to room temperature over 3 hours to obtain the SmBCO high-temperature superconducting bulk.

[0052] Step S423: After the sample growth is completed, the temperature of the high temperature furnace is lowered to room temperature within 3 hours.

[0053] Specifically, during the growth process, the first precursor embryo (CPP layer) of the upper layer of the combined precursor embryo is composed of RE123 and RE211, and the second precursor embryo (MPP layer) of the lower layer is composed of RE200 and RE023. At high temperatures, RE123 of the CPP layer will undergo non-uniform melting and transform into a combination of micron-sized RE211 solid phase and RE023 liquid phase. Since RE211 particles occupy a higher volume fraction in the CPP layer, a solid phase skeleton in the liquid phase is formed, and the lower MPP layer is mainly composed of RE023 liquid phase, in which RE200 exists in the form of nanometer size. Therefore, when the precursor embryo undergoes temperature increase, with the non-uniform melting of RE123, the solid phase skeleton of the CPP layer gradually increases, and the liquid phase of the lower MPP layer carries the RE200 particles upward for solute penetration, and reacts with the liquid phase in the CPP layer to generate extremely fine RE211 particles. Since the oxygen generated in this process is closer to the edge of the block, it is easier for oxygen to escape from the solid solution, and the porosity of the initial REBCO high-temperature superconducting bulk (C-MPP sample) is reduced. Since RE200 and RE023 generate very fine RE211 particles, which form more pinning centers with the RE123 matrix, the superconducting performance of the C-MPP sample is also increased.

[0054] Step S500: performing heat treatment on the initial REBCO high temperature superconducting bulk material to obtain a final REBCO high temperature superconducting bulk material.

[0055] Specifically, this step adjusts the oxygen content and distribution in the superconducting phase through post-heat treatment of oxygen permeation annealing, optimizes its crystal state, and improves the superconducting performance of the superconducting bulk material. It should be noted that step S500 includes step S510 and step S520.

[0056] Step S510, grinding and polishing the initial REBCO high temperature superconducting block to obtain a pre-treated block;

[0057] Step S520: Place the pretreated block material into a high temperature furnace with a flowing oxygen atmosphere, and perform oxygen annealing at 450° C. for 200 h to obtain a final REBCO high temperature superconducting block material.

[0058] Furthermore, after the REBCO high temperature superconducting bulk material is prepared, the present application also includes a performance test of the final REBCO high temperature superconducting bulk material (C-MPP sample). In order to illustrate the superiority of the prepared sample in terms of performance, two bulk materials were prepared under the same conditions using the traditional precursor powder formula and the refined precursor split formula and process, respectively, and were recorded as CPP sample and MPP sample.

[0059] The performance test method of REBCO superconducting bulk material covers two key aspects: porosity characterization and magnetic levitation force characterization. First, the porosity characterization accurately measures and compares the average size and volume fraction of pores through optical observation of the bulk material along the ac section and the use of image processing software. Figure 2 As shown in the figure, the C-MPP sample shows obvious advantages over the traditional MPP sample, significantly reducing the number of pores and porosity, and improving the mechanical properties and application potential of the superconducting bulk material.

[0060] Secondly, the magnetic levitation force characterization uses the zero-field cold magnetization method to evaluate the magnetic properties of the superconducting bulk material. This method involves fixing the sample on a permanent magnetic track, measuring its levitation force at different heights through liquid nitrogen cooling and a specific magnetization process, and the test results are shown in Table 1. Based on the force-area density and force-volume density data of different samples obtained, the performance of the C-MPP sample in superconducting performance can be accurately evaluated, proving that the C-MPP sample effectively improves the force-area / volume density of the sample on the basis of the CPP and is on par with the MPP sample, improving the superconducting performance of the superconducting bulk material while ensuring the mechanical properties.

[0061] Table 1 Force-area density and force-volume density of different samples

[0062]

[0063] In summary, this comprehensive testing method not only deeply analyzes the structural characteristics and mechanical properties of REBCO superconducting bulk materials, but also effectively evaluates their performance in practical applications, providing important theoretical support and experimental basis for further optimization and wide application of the technology.

[0064] The typical embodiments of the process described in detail above should be noted that in the preparation process of REBCO superconducting bulk materials, ordinary technicians in this field can make many modifications and changes according to this process method without creative work. Therefore, all technical solutions that can be obtained by technicians in this technical field based on the concept of this process method through logical analysis, reasoning and attempts on the basis of existing technologies, such as using NdBCO with a higher melting point to grow SmBCO and GdBCO high-temperature superconducting bulk materials with a lower melting point, should be within the scope of protection of this patent.

Claims

1. A method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo, characterized in that: include: Obtaining original drugs of a preset molar ratio, and preparing an original powder combination by a solid phase sintering method; A precursor powder combination is prepared by mixing the original powder combination, wherein the precursor powder combination includes a first precursor powder, a second precursor powder and a buffer layer powder, and the refined particle ratio of the second precursor powder is greater than the refined particle ratio of the first precursor powder; Based on a preset embryo production method, the precursor powder is combined and pressed to obtain a combined precursor embryo and a buffer layer, wherein the combined precursor embryo includes a second precursor embryo arranged at the bottom and a first precursor embryo placed coaxially and colaterally above the second precursor embryo; Based on a preset top seed crystal melt texturing method, the REBCO original seed crystal, the combined precursor embryo and the buffer layer are processed to obtain an initial REBCO high temperature superconducting bulk material; The initial REBCO high-temperature superconducting bulk material is subjected to heat treatment to obtain a final REBCO high-temperature superconducting bulk material.

2. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 1, characterized in that , obtaining the original medicine of the preset molar ratio, and preparing the original powder combination by solid phase sintering method, including: Weigh three portions of the original drug according to the molar ratios of RE2O3:BaCO3:CuO=1:4:6, 1:1:1 and 0:2:3; The three original drugs are mixed to prepare RE123 original powder, RE211 original powder and RE023 original powder respectively; The RE123 original powder, the RE211 original powder and the RE023 original powder are prepared by a solid phase sintering method to obtain purified RE123 powder, RE211 powder and RE023 powder.

3. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 2, characterized in that , a precursor powder combination is prepared by mixing the original powder combination, including: The RE123 powder and the RE211 powder are weighed and mixed in a molar ratio of 1:0.35, and 1 wt % of CeO2 powder is added to the mixed powder for mixing to obtain a first precursor powder; The RE200 powder and the RE023 powder are weighed and mixed at a molar ratio of 0.72:1, and 1 wt % of CeO2 powder is added to the mixed powder for mixing to obtain a second precursor powder; The RE123 powder and the RE211 powder were weighed and mixed in a molar ratio of 1:0.4, and 1 wt % of CeO2 powder was added to the mixed powder for mixing to obtain a buffer layer powder.

4. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 2, characterized in that The RE123 original powder, the RE211 original powder and the RE023 original powder are prepared by a solid phase sintering method to obtain purified RE123 powder, RE211 powder and RE023 powder, including: The RE123 raw powder is sintered in an air environment at 920° C. for 48 hours, the RE211 raw powder is sintered in an air environment at 930° C. for 48 hours, and the RE023 raw powder is sintered in an air environment at 880° C. for 48 hours to obtain sintered RE123 powder blocks, RE211 powder blocks, and RE023 powder blocks; The sintered RE123 powder block, the RE211 powder block and the RE023 powder block are ground and sintered three times to obtain purified RE123 powder, RE211 powder and RE023 powder.

5. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 2, characterized in that Based on the preset embryo production method, the precursor powder is combined and pressed to obtain a combined precursor embryo and a buffer layer, including: Weigh 20 g of the first precursor powder and put it into a square mold with a side length of 30 mm for pressurization to obtain a first precursor embryo; Weigh 20 g of the second precursor powder and put it into a square mold with a side length of 30 mm for pressurization to obtain a second precursor embryo; Placing the first precursor embryo body coaxially and colaterally on top of the second precursor embryo body to obtain a combined precursor embryo body; 0.25 g of the buffer layer powder was weighed and put into a cylindrical mold with a diameter of 6 mm for pressure pressing to obtain a buffer layer.

6. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 2, characterized in that , based on the preset top seed crystal melt texturing method, the REBCO original seed crystal, the combined precursor embryo and the buffer layer are processed to obtain the initial REBCO high temperature superconducting bulk material, including: Inserting the buffer layer between the REBCO original seed crystal and the combined precursor embryo body to obtain a coaxial combined structure, wherein the coaxial combined structure includes the REBCO original seed crystal, the buffer layer and the combined precursor embryo body coaxially from top to bottom; The combined structure is placed on an alumina ceramic plate and placed in a high-temperature furnace in an air atmosphere for texture growth, thereby obtaining an initial REBCO high-temperature superconducting bulk material induced by REBCO original seed crystal growth.

7. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 6, characterized in that: The buffer layer is inserted between the REBCO original seed crystal and the combined precursor embryo to obtain a coaxial combined structure, comprising: Selecting a 3 mm×3 mm×3 mm REBCO original seed crystal with a smooth base surface, and polishing the base surface of the REBCO original seed crystal to obtain a processed REBCO original seed crystal; The center axis of the processed REBCO original seed crystal perpendicular to the ground is respectively aligned with the center axis of the punch layer and the center axis of the combined precursor embryo, and the REBCO original seed crystal is placed between the buffer layer and the combined precursor embryo to obtain a coaxial combined structure.

8. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 6, characterized in that: The combined structure is placed on an alumina ceramic plate and placed in a high temperature furnace in an air atmosphere for texture growth, including: The temperature in the high-temperature furnace starts from room temperature and rises to 900°C after 1 hour and is kept at this temperature for 3 hours. Then, the temperature in the high-temperature furnace is raised to 1055°C and is kept at this temperature for 1 hour. The furnace temperature was lowered to 1005° C. within 30 minutes, and then the furnace temperature was lowered at a cooling rate of 0.2 K / h to 0.4 K / h, so that the REBCO original seed crystals in the furnace induced the combined precursor embryo to grow for 100 hours; After the sample growth was completed, the temperature of the high-temperature furnace was lowered to room temperature within 3 h.

9. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 1, characterized in that: The RE in the REBCO high temperature superconducting bulk material is selected from Y, Gd, Sm and Nd.

10. The method for preparing high-performance REBCO high-temperature superconducting bulk material based on a layered precursor embryo according to claim 1, characterized in that: The method further comprises: performing heat treatment on the initial REBCO high temperature superconducting bulk material to obtain a final REBCO high temperature superconducting bulk material; Grinding and polishing the initial REBCO high temperature superconducting block material to obtain a pretreated block material; The pretreated block material is placed in a high temperature furnace with a flowing oxygen atmosphere, and oxygen-annealed at 450° C. for 200 h to obtain a final REBCO high temperature superconducting block material.

Images