JP2010238633A - Method of manufacturing rare earth-based thick film oxide superconducting wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an Re-based (123) superconductor in a form of a thick film tape with a high critical current value. <P>SOLUTION: After forming a calcination film of a YBCO superconductor by repeating 16 times a step of applying a material solution containing trifluoroacetates of Y and Ba and naphthenate of Cu in proportion of Y:Ba:Cu=1:1.5:3 onto an oriented Ni-W substrate and heating them, a crystallization heat treatment is performed through a temperature raising process from a room temperature to a crystallization heat treatment temperature of 730°C, followed by a subsequent isothermal process. Water vapor is introduced into a furnace at a water vapor partial pressure of 1.05 vol% at the heat treatment temperature of 500°C, the water vapor partial pressure is increased to 2.6 vol% at 690°C before reaching the maximum heat treatment temperature, and then the water vapor partial pressure is further increased to 4.2 vol% stepwise when 30 minutes have passed after reaching the maximum heat treatment temperature of 730°C to retain this water vapor partial pressure during the isothermal process. A Jc value of the YBCO oxide superconductor is 1.48 MA/cm<SP>2</SP>at a film thickness of about 2.0 μm. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an oxide superconductor, and more particularly to a method for manufacturing an oxide superconducting wire useful for a superconducting magnet, a superconducting cable, a power device, and the like, and in particular, a thick film tape RE system suitable for the MOD method. (123) It relates to a method of manufacturing a superconducting wire.

  Oxide superconductors are expected to be applied to superconducting magnets, superconducting cables, power equipment, and the like because their critical temperature (Tc) exceeds the liquid nitrogen temperature, and various studies have been conducted earnestly.

In order to apply the oxide superconductor to the above-mentioned field, it is necessary to produce a long wire having a high critical current density (Jc) and a high critical current (Ic) value, Therefore, it is necessary to form an oxide superconductor on a metal tape from the viewpoint of strength and flexibility. Further, in order to be usable at a practical level equivalent to metal superconductors such as Nb ₃ Sn and Nb ₃ Al, an Ic value of about 500 A / cm (77 K, in a self magnetic field) is required.

Re-based oxide superconductors used in next-generation oxide superconducting wires, that is, ReBa _x Cu ₃ O _y- based oxide superconductors (where Re is Y, Nd, Sm, Gd, Eu, Yb, Pr, Ho Represents at least one element selected from Er, Dy, Tm, or La, and 1.3 ≦ x ≦ 2, hereinafter referred to as a Re-based (123) superconductor). Since the superconducting characteristics change, it is necessary to improve the in-plane orientation, and for this purpose, it is necessary to form an oxide superconductor on a tape-like substrate. In this case, in order to improve the Jc value, the c-axis of the oxide superconductor is oriented perpendicularly to the plate surface of the substrate, and the a-axis (or b-axis) is oriented in-plane parallel to the substrate surface. It is necessary to keep the superconducting state quantum connectivity well.

  A MOD method (Metal Organic Deposition Processes) is known as a method for producing a tape-shaped Re-based oxide superconductor. This MOD method thermally decomposes a metal organic acid salt. This is a method for forming a thin film on a substrate by applying a solution in which an organic compound of a metal component is uniformly dissolved on the substrate, and then thermally decomposing the solution. Therefore, it has an advantage suitable for manufacturing a long tape-shaped oxide superconducting wire.

  In the MOD method, when a metal organic acid salt that is a starting material is thermally decomposed, a carbonate of an alkaline earth metal (Ba or the like) is usually generated. An oxide superconductor by a solid-phase reaction via this carbonate. The formation of this requires high-temperature heat treatment at 800 ° C. or higher. Furthermore, when the film thickness is increased, nucleation for crystal growth occurs from a part other than the substrate interface, so it is difficult to control the crystal growth rate. As a result, a superconducting film having excellent in-plane orientation is obtained. It is difficult to obtain.

  In the MOD method, as a method of forming a Re-based (123) superconductor without passing through a carbonate, an organic acid salt containing fluorine (for example, TFA salt: trifluoroacetate) is used as a starting material in a water vapor atmosphere. In recent years, a method of obtaining a superconductor through the decomposition of fluoride by performing heat treatment has been vigorously performed. In the MOD method using the TFA salt as a starting material (hereinafter referred to as TFA-MOD method), a superconductor is generated by a reaction between an amorphous precursor containing fluorine obtained after calcination of a coating film and water vapor. Since the decomposition rate of fluoride can be controlled by the water vapor partial pressure during the heat treatment, the crystal growth rate of the superconductor can be controlled. As a result, a superconducting film having excellent in-plane orientation can be produced. Further, in this method, a Re-type (123) superconductor can be epitaxially grown from a substrate at a relatively low temperature.

As described above, when a tape-shaped oxide superconductor is manufactured by the MOD method, it is indispensable to increase the film thickness in order to improve the Jc value for practical use. In order to achieve this thickening by the MOD method using a TFA salt as a starting material, it is conceivable to increase the viscosity of the raw material solution containing the TFA salt to increase the thickness of the coating film. When the thickness is increased, the generation amount of HF and CO ₂ gas decomposed by heat treatment increases, so that a coating film is scattered during calcination, and as a result, a tape-shaped oxide superconducting thick film having high characteristics is manufactured. It ’s difficult.

  In order to produce a superconducting thick film, it is conceivable to increase the thickness of the coating film by repeating the coating and calcining steps. In this case, the in-plane orientation on the substrate was excellent by crystallization heat treatment. It becomes difficult to produce a superconducting crystal. The reason for this is considered to be that nucleation that becomes the nucleus of crystal growth occurs in a portion other than the substrate surface. In this case, decomposition of the metal organic acid salt including the TFA salt becomes insufficient, and the solvent and the organic acid tend to remain in the oxide superconducting precursor film obtained by calcination. Therefore, when the temperature rises during the subsequent crystallization heat treatment, the remaining organic acid such as fluoride rapidly decomposes and cracks and pores are generated in the film.

  This tendency becomes prominent when the oxide superconducting precursor film having a multilayer structure is formed by repeating coating and calcining heat treatment to increase the thickness. As a result, when the obtained precursor thick film is crystallized to obtain a superconducting film, epitaxial growth becomes difficult, it is difficult to obtain a superconducting thick film with excellent in-plane orientation, and the Jc characteristic reaches its peak. Furthermore, the Jc characteristics are significantly lowered due to the occurrence of cracks.

  In order to solve such a problem, an oxide superconductor capable of sufficiently decomposing a metal organic acid salt and enabling a high Jc value and a thick film by controlling a temperature rising rate during the calcining heat treatment is provided. It is known (for example, refer to Patent Document 1).

  Further, by controlling the calcining heat treatment temperature and / or the water vapor partial pressure of the introduced gas in the crystallization heat treatment atmosphere during the heat treatment of the oxide superconducting precursor formed on the substrate, it has high orientation and high Jc value. A method for producing a thick tape-shaped oxide superconductor is known (for example, see Patent Document 2).

  Furthermore, a method of manufacturing a thick film tape-shaped Re-based (123) superconductor on a substrate by performing an intermediate heat treatment between the calcining heat treatment and the heat treatment for generating the superconductor is known (for example, Patent Documents). 3).

Japanese Patent Laid-Open No. 2003-300726 JP 2003-34527 A JP 2007-165153 A

  However, the oxide superconductor of Patent Document 1 described above is subjected to a calcination heat treatment after applying a mixed solution of metal organic acid salt containing each metal element constituting the oxide superconductor in a predetermined molar ratio on the substrate. In the oxide superconductor obtained by subjecting the oxide superconductor precursor to a crystallization heat treatment, the calcining heat treatment is performed at a rate of temperature rise of 0.1 to 0.6 ° C./in an atmosphere having a water vapor partial pressure of 4.0 vol% or less. By controlling to the range of min, the metal organic acid salt is sufficiently decomposed, and when the rate of temperature rise is high, the metal organic acid salt remaining in the film rapidly decomposes during the crystallization heat treatment and cracks in the film Although a high Jc value and a thick film can be obtained by avoiding the problem of generation of pores and pores, although a high Jc value can be obtained, the film thickness is only about 0.9 μm and is practical Jc. It was insufficient for the thickening required to obtain the value.

  In addition, the oxide superconductor of Patent Document 2 described above is applied to a substrate with a mixed solution of TFA salt containing each metal element constituting the Re-based oxide superconductor in a predetermined molar ratio, and subjected to a calcining heat treatment. In the oxide superconductor obtained by subjecting the obtained precursor to crystallization heat treatment, the calcining heat treatment temperature excluding the precursor of the outermost layer is less than 400 ° C., and the water vapor partial pressure of the introduced gas in the crystallization heat treatment atmosphere is 4.0 vol. %, A thick tape-like oxide superconductor having high orientation and high Jc value is obtained, but the film thickness is only about 1.0 μm and is practical. It was similarly insufficient for the thickening required to obtain the Ic value.

  Furthermore, the oxide superconductor by the TFA-MOD method of Patent Document 3 described above is subjected to a calcining heat treatment after coating the raw material solution on the substrate, and then subjected to an intermediate heat treatment and a heat treatment for generating the superconductor. It is possible to reduce the residual pores in the film and to densify the film quality, and to produce a thick film tape-shaped Re-type (123) superconductor having a high Jc value and exceeding a thickness of about 2 μm. Since the intermediate heat treatment and the heat treatment for generating the superconductor are performed in an atmosphere having a water vapor partial pressure of 13.5% and the intermediate heat treatment needs to be performed multiple times, the steps after the calcined film formation are continued. There is a problem that the manufacturing process becomes complicated.

  As a result of diligent research, the present inventor has found that when a thick oxide superconductor is manufactured, crystal growth nuclei are generated in the entire area of the calcined film during the heat treatment process of superconductor generation, so that the orientation of the superconducting layer Has been found to be easily disturbed, resulting in a decrease in the Jc value.

  The present invention has been made on the basis of the above-mentioned knowledge. By controlling (changing) the water vapor partial pressure, which is a control factor of the crystal growth rate, in the heat treatment process of superconductor generation, growth of crystallites disturbing orientation is achieved. As a result, an object of the present invention is to provide a method for producing an oxide superconducting wire having a high Jc value by enabling orientation growth over the entire thick film.

  In order to achieve the above object, a method for producing a rare earth-based thick film oxide superconducting wire according to the present invention includes forming a calcined film of an oxide superconductor on a substrate via an intermediate layer, and then generating a superconductor. In the method of forming the Re-based (123) superconductor by performing the crystallization heat treatment, the crystallization heat treatment includes at least a temperature raising process before reaching the crystallization heat treatment temperature in an atmosphere in which the water vapor partial pressure increases. It is what I did.

  The object of the present invention can also be achieved by including the above-described crystallization heat treatment including at least a crystallization heat treatment temperature rise process and a crystallization heat treatment temperature constant temperature process performed in an atmosphere in which the water vapor partial pressure increases. can do.

  The calcined film of the oxide superconductor in the above invention is also formed by PLD method (Pulse Laser Deposition Processes) or MOCVD method (Metal Organic Chemical Vapor Deposition Processes). However, it is particularly preferable to form the film by the MOD method described above. In this case, the calcined film of the oxide superconductor has a predetermined film thickness after the crystallization heat treatment by applying the raw material solution containing the metal element constituting the oxide superconductor and repeating the calcining heat treatment a plurality of times. It is formed by being laminated so as to have.

When a Re-based (123) superconductor is formed by the TFA-MOD method, a mixed solution in which the metal molar concentration ratio is adjusted to a stoichiometric ratio (for example, Y: Ba: Cu = 1: 2: 3) is used. The formation of the oxide superconductor requires a heat treatment of 750 ° C. or more, and it takes a lot of time for the oxide superconductor and the metal substrate to react to form BaCeO ₃ and discharge the F element outside the film. In order to avoid this problem, it is effective to reduce the fluorine compound, and use a mixed solution having a molar concentration of 1.3 ≦ Ba ≦ 2, particularly a molar concentration of about 1.5. Thus, the oxide superconductor can be formed at a heat treatment temperature of 700 ° C. or higher.

According to the aforementioned Patent Document 3, the growth rate of YBa ₂ Cu ₃ O _7-y (hereinafter referred to as YBCO) by the TFA-MOD method increases as the water vapor partial pressure during crystallization increases, The Jc value also increases as the water vapor partial pressure increases. However, if the Jc value exceeds a certain value (P _H2O = 13.5%), the Jc value rapidly decreases due to generation of cracks and pores in the YBCO superconducting film. In terms of superconducting characteristics, there is a limit to the increase in the growth rate of the YBCO superconducting phase, and this tendency increases as the film thickness increases. In this case, the critical water vapor partial pressure at which cracks do not occur decreases as the YBCO film thickness increases, and from the viewpoint of speeding up, the thick film can be fired only under the water vapor partial pressure in the region where the growth rate is low. Intermediate heat treatment is performed at a temperature lower than the heat treatment temperature for superconductor generation, and before the crystallization temperature of YBCO is reached by this intermediate heat treatment, residual organic content or residual fluoride in the calcination is removed. It is discharged.

  In any case, in the prior art, the crystal growth rate of the superconductor can be controlled under a certain water vapor partial pressure from the viewpoint of superconducting properties by utilizing the fact that the decomposition rate of fluoride can be controlled by the water vapor partial pressure during the heat treatment. However, there is a problem that the orientation of the superconducting layer is likely to be disturbed by the generation of crystal growth nuclei throughout the calcined film.

  In the present invention, the intermediate heat treatment as described above is not required, and the crystallization heat treatment is performed in an atmosphere in which at least the water vapor partial pressure is increased. By including the temperature raising process before reaching the crystallization heat treatment temperature and the constant temperature treatment process of the crystallization heat treatment temperature performed in the atmosphere, orientation growth is possible over the entire thick film.

  In the above invention, the water vapor partial pressure during the crystallization heat treatment is preferably increased within a range of 13.5 vol% or less, particularly within a range of 2 vol% or less to 4 vol% or more.

The crystallization heat treatment temperature isothermal process is performed within a temperature range of 700 to 800 ° C., while the temperature rise process before the crystallization heat treatment temperature is reached, or the temperature rise process and the crystallization before the crystallization heat treatment temperature is reached. The atmosphere is controlled so that the water vapor partial pressure that increases in the constant temperature process of the heat treatment temperature increases continuously or stepwise. In this case, it is particularly preferable to include a crystallization heat treatment atmosphere in which the water vapor partial pressure increases within a temperature range of less than 550 ° C. to 680 ° C.
Moreover, the above steam atmosphere can be controlled in either an RTR (Reel to Reel) type electric furnace or a batch type electric furnace.

  The above crystallization heat treatment is performed under a total pressure of 1 to 760 Torr, and particularly preferably performed under a total pressure of 1 to 100 Torr. The heat treatment atmosphere includes water vapor, a gas that does not react with the oxide superconductor, and Consists of oxygen.

In the present invention, by increasing the water vapor partial pressure, which is a control factor of the crystal growth rate in the heat treatment process for generating the superconductor, it is possible to suppress the growth of crystallites that disturb the orientation, and to cover the entire thick film. Since orientational growth is possible, an oxide superconducting wire having a high Jc value can be produced. As a result, a Re-based (123) superconductor having a film thickness of 1.8 μm or more and a critical current density of 1.35 MA / cm ² can be obtained.

It is a graph which shows the heat processing temperature and water vapor partial pressure profile of the crystallization heat processing in one Example of this invention. It is a graph which shows the heat processing temperature and water vapor partial pressure profile of the crystallization heat processing in the other Example of this invention. It is a graph which shows the heat processing temperature and water vapor partial pressure profile of the crystallization heat processing in other Example of this invention.

As the substrate used in the present invention, either a biaxially oriented polycrystalline substrate or a non-oriented polycrystalline substrate can be used. As the oriented Ni substrate, RABiTS (trademark: rolling-assisted biaxially textured-substrates) obtained by subjecting a cold-rolled Ni substrate to heat treatment in a vacuum and highly oriented can be used. A thin film of an epitaxial layer of CeO ₂ and a thick film of YSZ (yttrium stabilized zirconia) are sequentially formed on the substrate.

On the other hand, when a non-oriented polycrystalline substrate is used, an IBAD method (Ion Beam Assisted Deposition) can be used. This composite substrate using the IBAD method is formed by depositing particles generated from a target while irradiating ions from an oblique direction to a non-magnetic high-strength tape-like Ni-based substrate (Hastelloy, etc.). Provided with an intermediate layer (CeO ₂ , Y ₂ O ₃ , YSZ, etc.) that suppresses the reaction with the elements constituting the superconductor, and the intermediate layer has a two-layer structure (YSZ or Zr ₂ R _x2 O ₇ / CeO ₂ or Y ₂ O ₃ etc .: R _x represents Y, Nd, Sm, Gd, Ei, Yb, Ho, Tm, Dy, Ce, La, or Er. (JP-A-4-329867, JP-A-4-33195, Japanese Patent Application No. 2000-333843).

  As the above Ni-based alloy, an alloy containing one or more elements selected from W, Mo, Cr, Fe, Cu, V, Sn and Zn in Ni can be used.

  The Re-based (123) superconductor in the present invention can be formed by the MOD method. In this case, any one or more of trifluoroacetate, octylate or naphthenate is used as the metal organic acid salt. In particular, the metal organic acid salt preferably uses a TFA-MOD method including at least trifluoroacetate (TFA salt). In this case, the raw material solution includes at least a metal organic acid salt of Ba and an organic solvent. It is more preferable to use a mixed solution.

  Examples of the present invention will be described below.

Example 1
Using a composite substrate in which an intermediate layer composed of Ce ₂ Zr ₂ O ₇ and CeO ₂ is sequentially formed on an oriented Ni-W substrate, Y and Ba trifluoroacetate and Cu naphthenate are formed on the composite substrate. Is applied to a raw material solution dissolved in 2-octanone so that Y: Ba: Cu = 1: 1.5: 3, heated at a maximum heating temperature of 400 ° C., and then furnace-cooled to room temperature. A calcined film was formed. This calcined film is formed by repeating the above process 12 times and 16 times so as to be about 1.45 μm and about 2.0 μm, respectively, after the crystallization heat treatment of the YBCO superconductor.

  Next, the calcination film on the composite substrate was subjected to crystallization heat treatment of YBCO superconductor according to the heat treatment temperature and water vapor partial pressure profile shown in FIG. This crystallization heat treatment is composed of a temperature rising process from room temperature to a maximum heat treatment temperature (crystallization heat treatment temperature) of 730 ° C., a constant temperature process at the crystallization heat treatment temperature, and a subsequent furnace cooling process to room temperature. Was kept below 50 Torr.

  Water vapor is introduced into the furnace under the conditions of an introduction start temperature of 500 ° C. and a water vapor partial pressure of 1.05 vol%, and the water vapor partial pressure is increased to 4.2 vol% at 690 ° C. before reaching the maximum heat treatment temperature. The water vapor partial pressure was maintained.

In this way, the result of measuring the YBCO oxide superconductor Jc values formed on the composite substrate, a thickness of about 1.45μm 1.57MA / cm ^2, at a thickness of about 2.0μm of 1.42MA / cm ² The value is shown.

Example 2
A calcined film was formed by the same method as in Example 1 except that the raw material solution was applied and heated at the maximum heating temperature, and then the furnace cooling step to room temperature was repeated 12 and 16 times.

  This calcined film is formed to have a thickness of about 1.45 μm and about 2.0 μm, respectively, after the crystallization heat treatment of the YBCO superconductor.

  Next, the calcination film on the composite substrate was subjected to crystallization heat treatment of YBCO superconductor according to the heat treatment temperature and water vapor partial pressure profile shown in FIG.

  This crystallization heat treatment is composed of a temperature rising process from room temperature to a maximum heat treatment temperature (crystallization heat treatment temperature) of 730 ° C., a constant temperature process at the crystallization heat treatment temperature, and a subsequent furnace cooling process to room temperature. Was kept below 50 Torr.

  Water vapor is introduced into the furnace under the conditions of an introduction start temperature of 500 ° C. and a water vapor partial pressure of 1.05 vol%, and the water vapor partial pressure is continuously increased to 4.2 vol% up to 690 ° C. before reaching the maximum heat treatment temperature. This water vapor partial pressure was maintained during the process.

In this way, the result of measuring the YBCO oxide superconductor Jc values formed on the composite substrate, a thickness of about 1.45μm 1.57MA / cm ^2, at a thickness of about 2.0μm of 1.38MA / cm ² The value is shown.

Example 3
A calcined film was formed by the same method as in Example 1 except that the raw material solution was applied and heated at the maximum heating temperature, and then the furnace cooling step to room temperature was repeated 12 and 16 times. This calcined film is formed to have a thickness of about 1.45 μm and about 2.0 μm, respectively, after the crystallization heat treatment of the YBCO superconductor.

  Next, the calcination film on the composite substrate was subjected to crystallization heat treatment of YBCO superconductor according to the heat treatment temperature and water vapor partial pressure profile shown in FIG.

  This crystallization heat treatment is composed of a temperature rising process from room temperature to a maximum heat treatment temperature (crystallization heat treatment temperature) of 730 ° C., a constant temperature process at the crystallization heat treatment temperature, and a subsequent furnace cooling process to room temperature. Was kept below 50 Torr.

  Steam is introduced into the furnace under the condition of an introduction start temperature of 500 ° C. and a steam partial pressure of 1.05 vol%, and the steam partial pressure is increased to 2.6 vol% at 690 ° C. before reaching the maximum heat treatment temperature. When 30 minutes passed after reaching the temperature of 730 ° C., the water vapor partial pressure was further increased stepwise to 4.2 vol%, and this water vapor partial pressure was maintained in the constant temperature process.

In this way, the result of measuring the YBCO oxide superconductor Jc values formed on the composite substrate, a thickness of about 1.45μm 1.57MA / cm ^2, at a thickness of about 2.0μm of 1.48MA / cm ² The value is shown.

Comparative Example A calcined film was formed in the same manner as in Example 1 except that the raw material solution was applied, heated at the maximum heating temperature, and then furnace-cooled to room temperature was repeated 10 times, 12 times, and 16 times. This calcined film is formed to have a thickness of about 1.23 μm, about 1.45 μm, and about 2.0 μm, respectively, after the crystallization heat treatment of the YBCO superconductor.

  Next, the calcined film on the composite substrate was subjected to crystallization heat treatment of the YBCO superconductor according to the heat treatment temperature profile shown in FIG.

  Water vapor was introduced into the furnace under the conditions of an introduction start temperature of 500 ° C. and a water vapor partial pressure of 1.05 vol%, and this water vapor partial pressure was kept constant until the constant temperature process of 730 ° C., the highest heat treatment temperature.

As a result of measuring the YBCO oxide superconductor Jc value formed on the composite substrate in this manner, the film thickness was about 1.23 μm, 1.42 MA / cm ² , the film thickness was about 1.45 μm, 1.58 MA / cm ² , A film thickness of about 2.0 μm was 1.1 MA / cm ² .

As is apparent from the results of Examples 1 to 3 and Comparative Example above, the crystallization heat treatment is performed from the room temperature to the maximum heat treatment temperature (crystallization heat treatment temperature), the constant temperature process at the crystallization heat treatment temperature, and the subsequent steps. When it is configured by a furnace cooling process up to room temperature and the water vapor partial pressure is kept constant, the Jc value is significantly reduced when the film thickness is about 2.0 μm, but before the crystallization heat treatment temperature is reached in the crystallization heat treatment. The temperature rising process, or the temperature rising process before reaching the crystallization heat treatment temperature and the crystallization heat treatment temperature constant temperature process,
By applying it in an atmosphere in which the partial pressure of water vapor increases continuously or stepwise, orientation growth can be achieved over the entire thick film, and a high Jc value can be achieved even in a thick film of about 2.0 μm. it can.

  Since the present invention makes it possible to increase the thickness of the superconductor, it is possible to produce a rare earth-based thick film oxide superconducting wire having a high Jc value, and to form the superconducting layer by the TFA-MOD method, which is a non-vacuum process. Thus, it is suitable for manufacturing a long wire, and its manufacturing cost can be remarkably reduced, and it can be applied to a conductive magnet, a superconducting cable, a power device, and the like.

Claims (9)

An oxide superconductor calcined film is formed on a substrate via an intermediate layer, and then subjected to a crystallization heat treatment for superconductor generation, whereby ReBa _x Cu ₃ O _y- based oxide superconductor (where Re is It represents at least one element selected from Y, Nd, Sm, Gd, Eu, Yb, Pr, Ho, Er, Dy, Tm or La, and 1.3 ≦ x ≦ 2 and y = 6.2 In the method for forming the Re-based (123) superconductor), the crystallization heat treatment is performed in an atmosphere in which at least the partial pressure of water vapor is increased. A method for producing a rare earth-based thick film oxide superconducting wire comprising a process. In the method for forming a Re-based (123) superconductor by forming a calcined film of an oxide superconductor on a substrate through an intermediate layer and then performing a crystallization heat treatment for superconductor generation, the crystallization heat treatment Includes a heating process before reaching the crystallization heat treatment temperature and an isothermal process of the crystallization heat treatment temperature performed in an atmosphere where the water vapor partial pressure is increased, and a method for producing a rare earth-based thick oxide superconducting wire, . The calcined film of the oxide superconductor is formed by applying a raw material solution containing a metal element constituting the oxide superconductor and performing a calcining heat treatment a plurality of times. 2. A method for producing a rare earth-based thick film oxide superconducting wire according to 2. The method for producing a rare earth-based thick film oxide superconducting wire according to any one of claims 1 to 3, wherein the water vapor partial pressure increases within a range of 13.5 vol% or less. The method for producing a rare earth-based thick film oxide superconducting wire according to claim 4, wherein the water vapor partial pressure increases within a range of 2 vol% or less to 4 vol% or more. 6. The rare earth-based thick film oxide superconductor according to claim 1, wherein the crystallization heat treatment includes an atmosphere in which a water vapor partial pressure increases within a temperature range of less than 550 ° C. to 680 ° C. or more. A manufacturing method of a wire. The method for producing a rare earth-based thick oxide superconducting wire according to any one of claims 1 to 6, wherein the crystallization heat treatment temperature is in a temperature range of 700 to 800 ° C. The method for producing a rare earth-based thick film oxide superconducting wire according to any one of claims 1 to 7, wherein the Re-based (123) superconductor is manufactured by a TFA-MOD method. 9. The rare earth-based thickness according to claim 1, wherein the Re-based (123) superconductor has a film thickness of 1.8 μm or more and a critical current density of 1.35 MA / cm ² or more. A method for producing a film oxide superconducting wire.

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