JP3045705B2 - Oxide-based superconducting material, method for producing the same, and apparatus using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
High critical current density (Jc) even in a magnetic field by compounding an oxide-based superconducting material showing a superconducting state at K or higher, a substrate, and an intermediate layer with controlled crystal orientation.
And a method of manufacturing such a superconductor. These inventions
Conventional superconducting magnet, superconducting NMR device, superconducting M
There are a wide range of advantages in terms of cost over RI, synchrotron and magnetic separation devices.

[0002]

2. Description of the Related Art In 1986, a copper oxide-based La-Ba-Cu-O perovskite-based superconductor having a high critical temperature was discovered (for example, Japanese Patent Application Laid-Open No. 63-260853). Temperature is Y-Ba-Cu-O system (MK Wu, JR Ashburn, CJ Torng,
Y. Q. Wand and C.I. W. Chu: Phys. Rev. Let
t. No. 58 (1987) 908) was found to be a 90K class superconductor in which application technology of a high temperature superconductor using liquid nitrogen as a refrigerant is expected.

[0003] Bi-Sr-Ca- having a higher critical temperature
Cu-O system (Tc: 110K, H. Maeda, Y. Tanak)
a, M. Fukutomi and T. Asano: Jpn. J. Appl.
Phys. 27 (1988) L209), Tl-Ba-C
a-Cu-O system (Tc: 120K ZZ Sheng and
A. M. Hermann: Nature 322 (1988) 55).
The research and development of new superconductors was remarkable.

[0004] In these general production methods, starting powders such as metal oxides or carbonates in the starting composition are mixed and pulverized repeatedly, and the mixture is heated to 800 to 1100 ° C in air, oxygen or a reducing atmosphere. It is obtained by performing a heat treatment at a temperature for several minutes to several hundred hours.

However, Y-Ba-Cu-O, Bi-Sr
The composite layered perovskite-type superconductor represented by —Ca—Cu—O and Tl—Ba—Ca—Cu—O has a plurality of structures having different levels and further has different characteristics. As a feature of the oxide-based superconductor, there is a large anisotropy in conductivity derived from its crystal structure. Therefore, in a superconducting film in which the crystal grain direction is disordered, the critical current density of zero magnetic field is 10 ³ A /
cm ² or less.

[0006] Further, when there is a different phase between crystal grains,
The different phase becomes a weak junction, and the critical current density becomes low, which is a serious problem when applied to a superconducting coil or the like.

In order to improve the critical current density, there have been proposed, for example, a method of orientation in which the crystal orientation of the intermediate layer is grown on the substrate in a uniform direction, and a method of fabricating the substrate in a uniform crystal direction. . For example, as a method of orientation in which the crystal orientation of the intermediate layer is grown in a uniform direction, a material obtained by subjecting an yttria-stabilized zirconia (YSZ) material to an oxide layer on a Hastelloy base material by Iijima et al. Ion beam assisted deposition (IBAD) for growing a superconducting film (Proceeding of 4th International)
Symposium Superconducting (Springer, Tokto,
1991)).

[0008] As a method of fabricating the base material with the same crystallographic direction, Kawashima et al.'S YSZ material (Pro
ceeding of 8th International Symposium Supercon
ducting (Springer, Tokto, 1996)) and Ito
SrTiO ₃ material (Y.Ito, Y.Yoshida,
M. Iwata, Y. Takai, I. Hirabayashi: Physica C
288 (1997) pp 178), a method of providing a superconducting film on a ceramic single crystal wire,
(g) A method of producing a substrate in which the crystal orientation of the substrate is aligned
No. 90816) and the like.

However, in the method of assisting an oxide layer on a metal substrate with an ion beam or the like, although the effect is shown for a short wire, the film formation rate is limited due to its selective growth. It is impossible to produce kilometer class wire rods. In addition, the method using a single crystal of a ceramic material is effective for a case of using a straight line or a short wire.

However, since it is a ceramic, a phenomenon such as cracking due to bending is a problem. Therefore, it is not very easy to produce a superconducting wire of kilometer class or more for producing a superconducting coil used for a superconducting magnet or the like.

[0011]

In the above prior art, the oxide superconductor is used as a superconducting wire and applied to a superconducting magnet. It is disclosed that it is important that the orientations of these are uniform.

Among these, a composite of a metal substrate and a superconductor having a uniform crystal direction and a method for producing them are promising as a superconducting wire in view of the production speed and the like.

[0013] Among metal substrates, metal materials such as a Ni substrate and an Ag substrate have been considered promising as substrates for superconductors. But N
The diffusion reaction of the i-base material with the superconductor proceeds during film formation or heat treatment, and impurities diffuse from the base material toward the superconductor. These cut off the current path of the superconductor and
It has been confirmed that a composition deviation of the superconductor is caused. Therefore, critical temperature (Tc) and critical current density (Jc)
Therefore, countermeasures have become an issue.

On the other hand, in the case of an Ag base material, a superconductor, especially LnBa ₂ containing YBa ₂ Cu ₃ O _7-y is disclosed by Budai et al.
It has been reported that the crystal direction of Cu ₃ O _7-y (Ln is a rare earth element) may be aligned in one direction or may be aligned in only two directions (JD Budai, RT Young). ,
B. S. Chao: Appl. Phys. Lett. 62 1993
P1836).

When the superconductor crystals are aligned in only two directions, Jc is lower than when the superconductor crystals are aligned in one direction because the conductive surface is divided in two directions as described above. Therefore, this is a major problem in reducing Jc in a magnetic field, and further in manufacturing a superconducting coil and the like.

An object of the present invention is to provide a new material and a manufacturing method for solving the problem of a low critical current density for practical use, and to provide a superconducting material having a high critical temperature and particularly a high critical current density in a magnetic field. An object of the present invention is to provide materials and devices and equipment using them.

[0017]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted various studies from various angles. As a result, they have invented the following superconducting material, its manufacturing method and an apparatus using the same. .

As the substrate, a metal substrate having a lattice constant close to that of the superconductor, for example, an Ag substrate and an Ag alloy substrate is used. Here, the Ag alloy base material is made of Ti, Au, Pt, or Ag.
Indicates a material containing Pd, Cu, and the like. As shown in FIG. 1, an Ln ₂ O ₃ layer 2 (Ln is Y
The above-mentioned problem can be overcome by using an oxide-based superconducting material characterized by forming a composite of the superconductor 1 and at least one selected from rare earth elements).

The Ag base and the Ag alloy base are 60
% Or more of the {100} plane is parallel to the interface between the metal and the superconductor within 20 degrees, and 60% of the metal crystal
If the <100> directions are aligned within 20 degrees with each other, the superconducting properties such as Tc and Jc are further improved.

Further, as the ratio of the {100} plane crystal of the Ag base material and the Ag alloy base material increases to 70% and 80%, the superconducting properties such as Tc and Jc thereof also improve. Furthermore, the angle of the metal in the <100> direction is 2
As the width of the angle of the crystal becomes narrower, that is, within 0 degrees and within 10 degrees, the superconducting characteristics such as Tc and Jc are improved.

The Ln ₂ O ₃ layer (Ln is at least one selected from the group consisting of Y and a rare earth element) is produced by a laser deposition method,
Physical vapor deposition such as sputtering, metal organic chemical vapor deposition (M
Chemical vapor deposition such as OCVD). In these production methods, in order to further improve the characteristics of the superconductor, L
The film formation temperature of the n ₂ O ₃ layer (Ln is at least one selected from Y or a rare earth element) is preferably 500 ° C. or higher. Furthermore, the characteristics of the superconductor are further improved as the production temperature becomes 600 ° C. or higher.

If the oxygen partial pressure at the time of fabrication is 10 Torr or less, the characteristics are improved. It is desirable that the Ln ₂ O ₃ layer (Ln is at least one selected from Y or rare earth elements) obtained by these manufacturing methods is of a cubic type.

The superconductor to be composited has a liquid nitrogen temperature of 77.
The present invention can be applied to any superconductor in a superconducting state at 64K or more which can be cooled by K or liquid nitrogen. In particular, the chemical composition of the superconductor is LnBa ₂ Cu ₃ O _7-y (where Ln is at least one selected from Y or a rare earth element,
The effect is remarkable in a superconductor made of an oxide-based superconducting material, wherein 0.5 ≦ y ≦ 0.2).

A superconducting system manufactured by a conventional superconducting technique, particularly a superconducting magnet, has been operated using liquid helium. By using the present invention, the operation can be performed using liquid nitrogen, so that the cost can be significantly reduced and the present invention is economically advantageous.

The superconducting wire using the superconducting material according to the present invention provides a superconducting magnet, an NMR apparatus, an MRI apparatus,
Superconducting systems such as synchrotron radiation devices and magnetic separation devices can be operated using liquid nitrogen.

In the method for producing the above-mentioned superconducting material, a metal substrate produced by a method such as a rolling method, particularly an Ag substrate or an Ag alloy substrate is used as a substrate. The {100} plane in which the crystal of the Ag base material or the Ag alloy base material is 60% or more is 2 deg.
The effect according to the present invention is remarkable when the directions are parallel within 0 degrees and the <100> directions of 60% or more of the metal crystals are aligned within 20 degrees from each other.

On these substrates, physical vapor deposition such as laser vapor deposition and sputtering, metal organic chemical vapor deposition (MOCVD)
Ln ₂ O ₃ (Ln is at least one selected from Y or rare earth elements) is deposited on a metal substrate in an atmosphere having a production temperature of 500 ° C. or more and an oxygen partial pressure of 10 Torr or less by a production method such as a chemical vapor deposition method. Make it. At this time, room temperature or 500 ° C
The same effect can be obtained by fabricating at the following temperature and then performing heat treatment at a temperature of 500 ° C. or higher. Further, a superconductor is formed in contact with the above-mentioned Ln ₂ O ₃ layer (Ln is at least one selected from Y or a rare earth element) and composited to obtain a superconductive material.

The superconductor can be applied to any condition as long as the superconductor is in a superconducting state at a liquid nitrogen temperature of 77K or 64K or more which can be cooled by liquid nitrogen. In particular, if the chemical composition of the superconductor is LnB
_{a 2 Cu 3 O 7-y} ( wherein Ln is at least one selected from Y or a rare earth element, -0.5 ≦ y ≦ 0.
The effect is remarkable in a superconductor made of an oxide-based superconducting material, which is characterized in 2).

The method for producing these superconductors is applied to all of the conventional methods. In particular, physical vapor deposition such as laser vapor deposition and sputtering, metal organic chemical vapor deposition (MO)
The effect is particularly remarkable in a production method by a chemical vapor deposition method such as CVD), a thick film method such as a plasma spraying method, a coating thermal decomposition method, a spray pyrolysis method, and a dip coating method.

The composite superconducting material produced by these methods is processed into a superconducting coil shape, and combined with equipment such as a power supply, a refrigerant tank for liquid nitrogen, etc., to form a superconducting magnet, NMR apparatus, MRI apparatus, synchrotron radiation. A superconducting system such as an optical device and a magnetic separation device can be manufactured.

[0031]

Embodiments of the present invention will be described below, but the present invention is not limited thereto.

Example 1 99.9% purity as a base material
Then, a 7 mm-wide Ag tape which is subjected to a rolling process by using the Ag material is manufactured. As a result of evaluating the crystal orientation of the Ag tape by X-ray diffraction measurement, the {100} plane of 60% or more is parallel to the interface between the metal and the superconductor within 20 degrees, and the metal crystal It is confirmed that 60% or more of <100> directions are aligned within 20 degrees from each other.

A Y ₂ O ₃ layer is formed on the substrate by sputtering. RF sputtering is performed under the condition that the target is Y
Output power 200 W, degree of vacuum 1.5 Pascal using ₂ O ₃ composition,
The film was formed at a substrate temperature of 700 ° C. for 3 hours while the distance between the target and the Ag base material was 4 mm. The obtained Y ₂ O ₃ film had a thickness of 1 μm by inductively coupled plasma emission spectrometry (ICP method), and the {111} plane was 20 mm away from the interface between the metal and the superconductor by X-ray diffraction measurement. It was confirmed that they were parallel within degrees.

Further, YBa ₂ Cu ₃
O _7-y is deposited. The deposition conditions of the laser vapor deposition method were as follows: a target having a YBa ₂ Cu ₃ O _7-y composition produced by a powder mixing method, a production temperature of 730 ° C., an oxygen partial pressure of 200 mTorr, a distance between the target and the base material of 40 mm, and a laser energy of The density was ² J / cm ² , the transmission frequency was 100 Hz, and the film formation time was 5 minutes. As a result, 1 μm YBa ₂
It was confirmed that the Cu ₃ O _7-y film was formed.

In order to confirm the crystal orientation of the composite, an extreme point measurement by an X-ray diffraction method was performed. As a result, it was confirmed that the crystal direction of the superconductor grew along the a-axis and the b-axis.

In order to measure Tc, Au was added to the superconductor surface.
Then, terminals were connected with Ag paste, and current-voltage measurement was performed by a DC method using liquid nitrogen as a refrigerant by a four-terminal method. The critical current (I) when the voltage between the measurement terminals is 1 μV / cm
Jc at liquid nitrogen temperature was determined from c). As a result, Tc exhibited a characteristic of 2 × 10 ⁵ A / cm ^{2 in} a zero magnetic field at a temperature of 87 K and Jc of 77 K.

Example 2 Ag material and Au as base materials
7m width rolled using a material containing 10%
Then, an Ag-Au alloy tape having a thickness of m is prepared. As a result of evaluating the crystal orientation of the tape by X-ray diffraction measurement, 70% or more of the {100} plane was parallel to the interface between the metal and the superconductor within 20 degrees, and the It was confirmed that 70% or more of the <100> directions were aligned within 20 degrees of each other.

Nd ₂ O ₃ was applied to this substrate by using a laser deposition method.
Form a layer. Using a target of Nd ₂ O ₃ composition produced by a powder mixing method, a production temperature of 800 ° C., an oxygen partial pressure of 20 mTorr, a distance between the target and the substrate of 40 mm, a laser energy density of ² J / cm ² , a transmission frequency of 30 Hz,
The film formation time was 5 minutes.

The obtained Y ₂ O ₃ film had a thickness of 0.5 μm according to inductively coupled plasma emission spectrometry (ICP method), and the {400} plane was determined by X-ray diffraction measurement to be between the metal and the superconductor. It was confirmed that it was parallel to the interface within 20 degrees.

Further, NdBa ₂ C
A film of u ₃ O _7-y is formed. The deposition conditions of the laser vapor deposition method were as follows: a target having a composition of NdBa ₂ Cu ₃ O _7-y prepared by a powder mixing method, a forming temperature of 830 ° C., an oxygen partial pressure of 100 mTorr, a distance between the target and the base material of 40 mm, and a laser energy The density was 3 J / cm ² , the transmission frequency was 50 Hz, and the film formation time was 10 minutes. As a result, it was 1.3 μm from the ICP method.
It was confirmed that the NdBa ₂ Cu ₃ O _7-y film was formed.

The orientation of the crystal of this composite was measured at the extreme points by the X-ray diffraction method. As a result, it was confirmed that the crystal direction of the superconductor grew along the a-axis and the b-axis.

In order to measure Tc, Au was added to the superconductor surface.
Then, terminals were connected with Ag paste, and current-voltage measurement was performed by a DC method using liquid nitrogen as a refrigerant by a four-terminal method. The critical current (I) when the voltage between the measurement terminals is 1 μV / cm
Jc at liquid nitrogen temperature was determined from c). As a result, Tc showed a characteristic of 7 × 10 ⁵ A / cm ^{2 in} a zero magnetic field at a temperature of 92 K and Jc of 77 K.

Example 3 A 10 mm-wide Ag-Cu roll-processed using an Ag-Cu alloy material as a base material
Make an alloy tape. As a result of evaluating the crystal orientation of the tape by X-ray diffraction measurement, 70% or more of the {100} plane was parallel to the interface between the metal and the superconductor within 20 degrees, and the It was confirmed that 70% or more of the <100> directions were aligned within 20 degrees of each other.

The substrate was coated with Sm ₂ O ₃ using a laser deposition method.
Form a layer. Using a target having an Sm ₂ O ₃ composition prepared by a powder mixing method, a preparation temperature of 700 ° C., an oxygen partial pressure of 20 mTorr, a distance between the target and the base material of 40 mm, a laser energy density of 1 J / cm ² , a transmission frequency of 30 Hz,
The film formation time was 5 minutes.

The obtained Sm ₂ O ₃ film had a thickness of 0.3 μm according to inductively coupled plasma emission spectrometry (ICP method). It was confirmed that it was parallel to the interface of the superconductor within 20 degrees.

Further, SmBa ₂ C
A film of u ₃ O _7-y is formed. The film forming conditions of the laser vapor deposition method are as follows: a target having an SmBa ₂ Cu ₃ O _7-y composition prepared by a powder mixing method, a forming temperature of 830 ° C., an oxygen partial pressure of 100 mTorr, a distance between the target and the base material of 40 mm, laser energy The density was 1 J / cm ² , the transmission frequency was 10 Hz, and the film formation time was 30 minutes. As a result, 0.8 μm was obtained from the ICP method.
It was confirmed that the NdBa ₂ Cu ₃ O _7-y film was formed.

The crystal orientation of the composite was measured at the extreme points by the X-ray diffraction method. As a result, it was confirmed that the crystal direction of the superconductor was growing along the a-axis and the b-axis. In order to measure Tc, terminals were connected to the surface of the superconductor with Au and Ag paste, and current-voltage measurement was performed by a DC method using liquid nitrogen as a refrigerant by a four-terminal method. 1μ voltage between measuring terminals
Jc at the liquid nitrogen temperature was determined from the critical current (Ic) at V / cm. As a result, Tc is 90K, J
c exhibited a characteristic of 5 × 10 ⁵ A / cm ^{2 in} a zero magnetic field at a temperature of 77K.

Example 4 An Ag-Au alloy tape having a width of 3 mm, which was rolled using an Ag-Au alloy material as a base material, was prepared. As a result of evaluating the crystal orientation of the tape by X-ray diffraction measurement, 80% or more of the {100} plane is parallel to the interface between the metal and the superconductor within 20 degrees, and It was confirmed that 80% or more of the <100> directions were aligned within 20 degrees of each other.

On this substrate, Y ₂ O ₃ and YBa ₂ Cu ₃ O _7-y are produced by using the MOCVD method. The MO raw materials used were Y (DPM) ₃ , Ba (DPM) ₂ and Cu (DPM) ₂ .

The holding temperature of each MO raw material is 125
C., 240.degree. C. and 120.degree. The reaction tube pressure was set at 10 Torr. First, Y ₂ O ₃ is prepared at a temperature of 700 ° C.
Was performed for 10 minutes, and YBa ₂ Cu ₃ O _7-y was prepared at a temperature of 800 ° C. for 1 hour.

FIG. 2 shows the result of a pole measurement of the crystal orientation of the composite by the X-ray diffraction method. In this measurement, the YBCO (103) plane was used as the measurement plane. It was confirmed that the crystal direction of the superconductor grew along the a-axis and the b-axis.

In order to measure Tc, Au was added to the surface of the superconductor.
Then, terminals were connected with Ag paste, and current-voltage measurement was performed by a DC method using liquid nitrogen as a refrigerant by a four-terminal method. The critical current (I) when the voltage between the measurement terminals is 1 μV / cm
Jc at liquid nitrogen temperature was determined from c). As a result, Tc exhibited characteristics of 1 × 10 ⁵ A / cm ^{2 in} a zero magnetic field at a temperature of 85 K and Jc of 77 K.

FIG. 3 shows the change in Jc at 77 K when a magnetic field was applied up to 1 Tesla perpendicular to the film surface of the composite.

[Comparative Example 1] YBa ₂ Cu ₃ O _7-y is manufactured by MOCVD using an Ag-Au alloy material having the same orientation as in Example 4. The MO raw material used was Y
(DMP) ₃ , Ba (DMP) ₂ and Cu (DMP) ₂ . The holding temperature of each MO raw material is 125 ° C, 240
C. and 120.degree. The reaction tube pressure was set at 10 Torr. YBa ₂ Cu ₃ O _7-y was produced at a production temperature of 800 ° C. for 1 hour.

FIG. 4 shows the results of pole measurement of the crystal orientation of this composite by X-ray diffraction. It was confirmed that a crystal in which the crystal direction of the superconductor was rotated by 45 degrees on the film surface together with the a-axis and the b-axis was growing.

In order to measure Tc, Au was added to the surface of the superconductor.
Then, terminals were connected with Ag paste, and current-voltage measurement was performed by a DC method using liquid nitrogen as a refrigerant by a four-terminal method. The critical current (I) when the voltage between the measurement terminals is 1 μV / cm
Jc at liquid nitrogen temperature was determined from c). As a result, Tc exhibited characteristics of 1 × 10 ⁴ A / cm ^{2 in} a zero magnetic field at a temperature of 84 K and Jc of 77 K.

FIG. 3 shows the change in Jc at 77 K when a magnetic field was applied up to 1 Tesla perpendicular to the film surface of the composite.

The effect of the present invention was confirmed to be remarkable from the change of Jc in the zero magnetic field and the magnetic field of Example 4 and Comparative Example 1.

[0059]

According to the present invention, it is possible to improve the deterioration of superconductivity between crystal grains of the oxide superconductor. Furthermore, according to the present invention, a large area film can be formed.
It can be effectively applied to energy fields such as magnetic shields and superconducting coils.

[Brief description of the drawings]

FIG. 1 is a schematic structural view of an oxide-based superconducting material obtained by the present invention.

FIG. 2 is a diagram showing the results of pole measurement of the oxide superconducting material obtained in Example 4.

FIG. 3 is a diagram showing the results of Jc measurement in a magnetic field of the oxide superconducting materials obtained in Example 4 and Comparative Example 1.

FIG. 4 is a graph showing the results of pole measurement of the oxide superconducting material obtained in Comparative Example 1.

[Explanation of symbols]

1 ... superconductor, 2 ... Ln ₂ O ₃ layer, 3 ... metal substrate 4 ... Examples 4 and 5 ... Comparative Example 1.

──────────────────────────────────────────────────続 き Continuing from the front page (73) Patent holder 000005290 Furukawa Electric Co., Ltd. 2-6-1 Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Kazuhisa Higashiyama 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Shares (72) Inventor Takashi Yoshida 2-4-1 Rokuno, Atsuta-ku, Nagoya-shi, Aichi Pref. International Research Institute for Superconducting Technology Nagoya Research Laboratory, Superconductivity Engineering Laboratory (72) Inventor Masato Hasegawa 2-4-1 Rokuno, Atsuta-ku, Nagoya-shi, Aichi Pref. International Superconducting Industrial Technology Research Center Nagoya Laboratory, Superconductivity Research Institute (72) Inventor Kaname Matsumoto 2-4-1, Rokuno, Atsuta-ku, Nagoya-shi, Aichi No. International Superconducting Technology Research Center Nagoya Research Institute for Superconducting Engineering In-house (72) Inventor Izumi Hirabayashi 2-4-1 Rokuno, Atsuta-ku, Nagoya-shi, Aichi Pref. International Superconducting Technology Research Center Nagoya Laboratory, Superconducting Engineering Laboratory (56) References Akihiro K. et al. , "Synthesis of B iaxially Aligned Y 2O3 Buffer Layer D irectly on Ni Tape s through the Elec tron Beam Depositi on," Advances in su per conductivity X (Proceedings of th e 10th Iternational Symposium on Supr conductivity (ISS '97), October 27-30, 1997, Gifu), Vol. 2,15 July 1998, pp. 139-157. 615-618 Ichinose A. et al. , "Deposition of Y2O3 buffer layers on biaxially-text ured metal substrates," Physica C, Vol. 302, no. 1, 10 June 1998, pp. 51-56 Shoji Tanaka et al., “What is Superconductivity?”, 1st edition, Nikkei Inc., June 15, 1987, pp. 61-93 (58) Field surveyed (Int. Cl. ⁷ , DB name) C30B 1/00-35/00 CA (STN) REGISTRY (STN)

Claims (22)

(57) [Claims] 1. A substrate made of a polycrystalline Ag or Ag alloy material, and an Ln ₂ O ₃ layer (Ln is selected from Y or a rare earth element) having crystals aligned on the surface of the substrate between the substrate and the superconductor. An oxide-based superconducting material characterized in that at least one selected from the group consisting of at least one of the above is used as an intermediate layer. 2. A polycrystalline made of Ag or an Ag alloy substrate crystal substrate surface is uniform, Ln ₂ O ₃ layer crystals are aligned on the substrate surface between the substrate and the superconductor ( Ln is at least one selected from the group consisting of Y and rare earth elements) as the intermediate layer. 3. The {100} plane of at least 60% of the polycrystalline Ag or Ag alloy metal crystal is parallel to the interface between the metal and the superconductor within 20 degrees, and the metal crystal has a thickness of 60%. % Or more of <100> directions are aligned within 20 degrees from each other, and Ln ₂
O ₃ layers (Ln is at least one selected from Y or a rare earth element) oxide based superconducting material characterized by being configured as an intermediate layer. 4. A polycrystalline Ag or Ag alloy metal crystal having at least 70% of its {100} planes parallel to the interface between the metal and the superconductor within 20 degrees and 60% of the metal crystal. % Or more of <100> directions are aligned within 20 degrees from each other, and Ln ₂
O ₃ layers (Ln is at least one selected from Y or a rare earth element) oxide based superconducting material characterized by being configured as an intermediate layer. 5. A polycrystalline Ag or Ag alloy metal crystal, wherein at least 70% of the {100} plane is parallel to the interface between the metal and the superconductor within 20 degrees and 60% of the metal crystal. % Or more of the <100> directions are aligned within 10 degrees with each other, and at least 60% of the {100} plane of the metal crystal between the base material and the superconductor is formed by the metal and Y _2.
Ln ₂ O ₃ parallel to the interface of the O ₃ layer within 10 degrees
An oxide-based superconducting material comprising a layer (Ln is at least one selected from Y or a rare earth element) as an intermediate layer. 6. A {100} plane of at least 70% of the polycrystalline Ag or Ag alloy metal crystal is parallel to the interface between the metal and the superconductor within 20 degrees, and 60% of the metal crystal. % Or more of the <100> directions are aligned within 10 degrees with each other, and at least 70% of the {100} plane of the metal crystal is between the substrate and the superconductor.
L which is parallel to the interface of the ₂ O ₃ layer (Ln is at least one selected from Y or rare earth elements) within 10 degrees
n ₂ O ₃ layer (Ln is at least one selected from Y or a rare earth element) oxide based superconducting material characterized by being configured as an intermediate layer. 7. A {100} plane of at least 80% of the metal crystal of the polycrystalline Ag or Ag alloy is parallel to the interface between the metal and the superconductor within 20 degrees, and 60% of the metal crystal. % Or more of the <100> directions are aligned within 10 degrees with each other, and between the substrate and the superconductor, at least 60% of the {100} plane of the metal crystal is formed by the metal and Ln.
L which is parallel to the interface of the ₂ O ₃ layer (Ln is at least one selected from Y or rare earth elements) within 10 degrees
n ₂ O ₃ layer (Ln is at least one selected from Y or a rare earth element) oxide based superconducting material characterized by being configured as an intermediate layer. 8. The oxide superconducting material according to claim 1, wherein the Ln ₂ O ₃ layer (Ln is at least one selected from Y or a rare earth element) has a cubic crystal structure. An oxide-based superconducting material. 9. The oxide superconducting material according to claim 1, wherein the chemical composition of the superconductor is LnBa.
_{2 An} oxide superconducting material in which Cu ₃ O _7-y (Ln is at least one selected from Y or a rare earth element, and −0.5 ≦ y ≦ 0.2). 10. A {100} plane of at least 80% of the metal crystal of the polycrystalline Ag or Ag alloy is parallel to the interface between the metal and the superconductor within 20 degrees, and 60% of the metal crystal. % Or more of the <100> directions are aligned within 10 degrees with each other, and at least 60% of the {100} plane of the metal crystal is between the base and the superconductor.
n ₂ O ₃ layer (Ln is at least one selected from Y or a rare earth element) of at least 1 Ln ₂ O ₃ layer (Ln parallel within 20 degrees to the interface selected from Y or a rare earth element A method for producing an oxide-based superconducting material, comprising: forming a seed layer as an intermediate layer in an atmosphere at a substrate temperature of 500 ° C. or higher. 11. A {100} plane of at least 80% of a polycrystalline Ag or Ag alloy metal crystal is parallel to the interface between the metal and the superconductor within 20 degrees, and 60% or more of the <100> directions are aligned within 10 degrees with each other, and at least 60% or more of the {100} plane of the metal crystal is formed between the substrate and the superconductor by the metal and Ln _2. Ln ₂ O ₃ layer (Ln is at least one selected from Y or rare earth element) parallel to the interface of the O ₃ layer (Ln is at least one selected from Y or rare earth element) within 20 degrees Forming an oxide layer as an intermediate layer in an atmosphere at a substrate temperature of 600 ° C. or higher. 12. The {100} plane of at least 80% of the polycrystalline Ag or Ag alloy metal crystal is parallel to the interface between the metal and the superconductor within 20 degrees, and 60% of the metal crystal. % Or more of the <100> directions are aligned within 10 degrees with each other, and at least 60% of the {100} plane of the metal crystal is between the base and the superconductor.
n ₂ O ₃ layer (Ln is at least one selected from Y or a rare earth element) of at least 1 Ln ₂ O ₃ layer (Ln parallel within 20 degrees to the interface selected from Y or a rare earth element A method for producing an oxide-based superconducting material, comprising: forming a seed as an intermediate layer in an atmosphere having a substrate temperature of 600 ° C. or higher and an oxygen partial pressure of 10 Torr or lower. 13. The Ln ₂ O ₃ layer formed in an atmosphere in which the substrate temperature is 600 ° C. or more and the oxygen partial pressure is 10 Torr or less according to claim 11 or 12, wherein the Ln ₂ O ₃ layer is formed by physical vapor deposition, chemical vapor deposition, A method for producing oxide-based superconducting materials formed by laser vapor deposition, sputtering, or metal organic chemical vapor deposition. 14. A superconducting magnet using the oxide superconducting material according to claim 1. 15. A superconducting magnet using an oxide superconducting material produced by the method for producing an oxide superconducting material according to claim 10. 16. An NMR apparatus using the superconducting magnet according to claim 14 or 15. 17. A synchrotron radiation light generator using the superconducting magnet according to claim 14. 18. A magnetic separation device using the superconducting magnet according to claim 14 or 15. 19. NMR apparatus characterized by using a superconducting magnet according to claim 1 4 or 15. 20. An MRI apparatus using the superconducting magnet according to claim 14 or 15. 21. synchrotron apparatus characterized by using a superconducting magnet according to claim 1 4 or 15. 22. A magnetic separation device using the superconducting magnet according to claim 14 or 15.