JP5405069B2 - Tape-shaped oxide superconductor and substrate used therefor - Google Patents

Description

  The present invention relates to an oxide superconductor suitable for use in power equipment such as a power transmission cable and a power storage system and a power equipment such as a motor and a substrate used therefor, and in particular, heating and baking after coating a precursor film. The present invention relates to a tape-shaped oxide superconductor suitable for an oxide superconductor manufactured by using a film forming method (hereinafter referred to as MOD method) for forming a ceramic thin layer on a substrate and a substrate used therefor.

Oxide superconductor, the critical compared to alloy-based superconductors, such as a conventional Nb ₃ Sn-based temperature (Tc) is high, transmission cables, transformers, motors, operate application equipment such electric power storage system at the temperature of liquid nitrogen Because of what we can do, research into making it into wire has been vigorously conducted. Among them, ReBa ₂ Cu ₃ O _7-y (Re = Y, Nd, Sm, Gd, Eu, Yb, Pr, or Ho represents at least one kind of element, hereinafter referred to as ReBCO) superconductor Has a small attenuation of energization current in the high magnetic field region, that is, the magnetic field characteristics at the liquid nitrogen temperature are superior to those of the Bi-based superconductor, so that a practical high critical current density (Jc) can be maintained. In addition to excellent characteristics in the high temperature range, it is possible to make a process that does not use silver, which is a noble metal, and because liquid nitrogen can be used as a refrigerant, the cooling efficiency is remarkably improved. As a next-generation superconducting material, it is expected to be used as a wire.

  The crystal system of the ReBCO superconductor is orthorhombic, the lengths of the three sides of the x-axis, y-axis, and z-axis are different, and the angles between the three sides of the unit cell are slightly different, so twins are formed. Since a slight misalignment easily generates twin grain boundaries and lowers the current-carrying characteristics, in order to bring out the material characteristics in the current-carrying characteristics, not only align the CuO plane in the crystal but also the crystal in the plane. Since it is required to align the orientation, it is difficult to make the wire as compared with the Bi-based oxide superconductor.

For this reason, the ReBCO superconducting wire is generally formed by forming at least one or more biaxially oriented oxide layers as an intermediate layer on a metal substrate, further forming an oxide superconducting layer thereon, further protecting the surface of the superconducting layer and It has a structure in which a stabilizing layer that plays a role of a protective circuit in the case of over-electricity improvement and overcurrent is laminated. As a general the above intermediate layer, although CeO ₂ is often used, which, CeO ₂ intermediate layer is excellent in lattice matching and oxidation resistance of the ReBCO layer, and excellent most for a small reactivity with ReBCO layer According to what is known as one of the intermediate layers.

  Also, in superconducting wires that are expected to be used in recent years, in order to secure a bypass circuit when an accident current is energized, electrical resistance is low and thermal conductivity is high on the superconducting layer, for example, copper tape. Bonding structures are also being studied.

  The critical current characteristics of the ReBCO superconductor depend on the in-plane orientation of the superconducting layer and are known to be greatly affected by the in-plane orientation and surface smoothness of the underlying intermediate layer. The manufacturing method of increasing the in-plane orientation and forming the wire while aligning the in-plane orientation is the same as the manufacturing method of the thin film.

  That is, by forming an intermediate layer with improved in-plane orientation and orientation on a tape-shaped metal substrate and using the crystal lattice of this intermediate layer as a template, the in-plane orientation and orientation of the crystal of the ReBCO superconducting layer Currently, various manufacturing processes have been studied, and various composite substrates in which an in-plane oriented intermediate layer is formed on a tape-shaped metal substrate are used. It is essential that the intermediate layer on the tape-shaped metal substrate is biaxially oriented. As this composite substrate, a method using a biaxially-oriented metal substrate and a method using a non-oriented metal substrate as the tape-shaped metal substrate. It has been known.

As the composite substrate using the former biaxially oriented metal substrate, (i) Ni or Ni-based alloy which is easy to form a texture and excellent in lattice matching, and cold-worked Ni substrate is used in a vacuum. A CeO ₂ thin layer and a YSZ layer (or a CeO ₂ thin layer thereon) were provided on an oriented Ni substrate (RABiTS / trademark: rolling-assisted biaxially textured-substrates) subjected to heat treatment in (B) a non-oriented non-magnetic first metal layer and a second metal layer bonded to the first metal layer and having a cubic texture in which at least the surface layer is oriented, The metal layer has higher strength than the second metal layer, and an intermediate layer is formed on the second metal layer of the film-forming alignment substrate having high strength while maintaining good orientation (for example, patent Reference 1) and (c) Heat resistance and oxidation resistance A composite substrate is known in which a biaxially oriented Ni or Ni-based alloy or Cu or Cu-based alloy is provided on a metal substrate having one or two intermediate layers such as CeO2 formed thereon (for example, patents) Reference 2).

On the other hand, as a method of using a non-oriented metal substrate for the latter composite substrate, a method using an IBAD (Ion Beam Assisted Deposition) process is currently known as a method that exhibits the highest critical current characteristics. In this method, a polycrystalline non-magnetic high-strength tape-like Ni-based substrate (Hastelloy et al .: trademark) is irradiated from a target while irradiating ions from a certain angle with respect to the normal of the Ni-based substrate The generated particles are deposited by laser vapor deposition (PLD), and the intermediate layer (CeO ₂ , Y ₂ O ₃ , which has a fine crystal grain size and high orientation and suppresses reaction with the elements constituting the superconductor, YSZ or the like) or an intermediate layer having a two-layer structure (YSZ or Rx ₂ Zr ₂ O ₇ / CeO ₂ or Y ₂ O ₃ or the like: Rx is Y, Nd, Sm, Gd, Ei, Yb, Ho, Tm, Dy, (Indicating Ce, La or Er.) (Or a CeO ₂ layer thereon) (see, for example, Patent Documents 3 to 5).

JP 2006-127847 A JP 2007-115562 A JP-A-4-329867 Japanese Patent Laid-Open No. 4-331895 JP 2002-203439 A

  However, in the method (a) using a biaxially oriented metal substrate for the composite substrate, the metal substrate such as a Ni-based alloy is thinned as a result of being strongly rolled to form a texture. Because the amount of added elements is small, mechanical strength decreases to several tens to 150 MPa when orientation heat treatment is performed at a high temperature, which not only affects handling during subsequent film formation, but also electromagnetics during use of the wire. There were problems such as inability to withstand power.

  In (b) above, in order to reinforce the strength of the second orientation substrate, the first metal layers having high strength are bonded to each other by a method such as rolling. There is a problem that the bonding strength is not sufficient in handling during film formation or coil formation.

  Furthermore, in the above (c), since it has a structure in which a metal substrate having heat resistance and oxidation resistance is bonded to a Ni-base alloy or the like or a Cu-base alloy or the like, it has excellent mechanical strength, but two layers of metal Since the plate is formed by performing an orientation heat treatment after being bonded by cold working, the problem is that the bonding strength is not sufficient in handling during subsequent film formation or coil formation, as in (a) above. There is.

  On the other hand, in the method based on the IBAD process using a non-oriented metal substrate as the composite substrate, a polycrystalline non-magnetic high-strength tape-shaped Ni-based substrate is used, and an intermediate layer is directly formed on the substrate. Therefore, although there are few problems in terms of strength, these conventional techniques, including the cases (a) to (c) above, have the following problems.

  That is, it is known that the critical current value (Ic) of the ReBCO superconductor depends on the applied strain. For example, the YBCO superconductor does not show a decrease in Ic with respect to a compression strain of 1%. It is known that cracks occur in the superconducting film at a tensile strain of 7%, and that the Ic decreases rapidly as the tensile strain increases further, and does not recover even when the strain is removed.

  For this reason, when a superconducting coil is formed using a tape-shaped oxide superconductor in which a superconducting layer and a stabilizing layer are formed on an intermediate layer of a composite substrate, compressive strain is added to the superconducting layer ( Winding is usually performed with the metal substrate on the outside. In this case, since the stabilizing layer such as silver is located in the innermost layer, the electrode cannot be directly connected to silver which is a good conductor, and the metal substrate located in the outermost layer has high resistance. Furthermore, since there is an oxide intermediate layer that is an insulator between the superconducting layer and the connection substrate, there is a problem that current cannot be applied efficiently.

  As described above, in the ReBCO superconducting wire intended for equipment application, a structure in which a copper tape having low electrical resistance and high thermal conductivity is laminated on the superconducting layer has been studied. As a method of laminating a copper tape on the surface, a method of pressure bonding after immersion in a solder bath, a method of bonding with a heating roll after solder plating, a method of molding with a heating roll with a solder tape interposed, and the like have been studied so far. However, since the surface of the superconducting layer is covered with an oxide film by the crystallization heat treatment of the superconducting layer, there is a problem that sufficient bonding strength cannot be obtained.

  In addition, in the ReBCO superconducting wire in which a copper tape is bonded on the superconducting layer, the thermal conductivity of copper is large, so that there is a problem that the superconducting layer cannot be thinned by laser processing.

In other words, the hysteresis loss due to the magnetic flux pinning phenomenon is very small, but it hinders cooling when superconductors are applied to AC devices, and causes an increase in cooling cost and quenching. Therefore, it is important to reduce hysteresis loss. In order to solve this problem, for example, as shown in FIG. 3, a Gd—Zr—O intermediate layer 32, CeO ₂ intermediate layer 33, YBCO superconducting layer 34, and Ag are formed on the Hastelloy 31 by the IBAD method. The surface of the tape-shaped superconducting wire 30 on which the stabilization layer 35 is sequentially formed is divided along the current path by irradiating a laser beam, but a copper tape having a high thermal conductivity on the stabilization layer 35. In the case of the structure in which is bonded, the superconducting layer cannot be thinned by laser processing because the thermal conductivity of copper is large.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a tape-shaped oxide superconductor that is excellent in heat dissipation and can be easily thinned by a laser process.

  Another object of the present invention is to provide a tape-shaped oxide superconductor excellent in connectivity when forming a superconducting coil and a substrate used therefor.

  Another object of the present invention is to provide a tape-shaped oxide superconductor excellent in mechanical strength and bonding strength and a substrate used therefor.

The tape-shaped oxide superconductor of the present invention was made to solve the above problems,
One or more intermediate layers and an oxide superconducting layer made of a biaxially oriented inorganic material on the first metal layer of the substrate in which the first metal layer and the second metal layer as the core material are joined. In the oxide superconductor composed of a laminate in which the first metal layer and the second metal layer are formed, the mechanical strength of the second metal layer is greater than that of the second metal layer and is non-oriented and nonmagnetic nickel-based alloy or stainless steel, and in a temperature range of 100～300K, thermal conductivity of 100W / m · K or more copper, Rutotomoni using silver, gold, aluminum or an alloy containing these as a main material, a first metal layer a second The metal layer is bonded through a bonding layer by performing a heat treatment after surface activation bonding .

Another tape-shaped oxide superconductor according to the present invention is an inorganic material biaxially oriented on a first metal layer of a substrate obtained by bonding a first metal layer and a second metal layer as a core material. In the oxide superconductor composed of a laminate in which one or a plurality of intermediate layers and oxide superconducting layers are formed, the second metal layer is mechanically coupled to the first metal layer and the second metal layer, respectively. greater than the intensity, and the non-magnetic non-oriented nickel-based alloy or stainless steel, and in a temperature range of 100～300K, copper thermal conductivity of more than 100W / m · K, silver, gold, aluminum or these as a main material And the first metal layer and the second metal layer are bonded via the bonding layer by performing a heat treatment after the surface activation bonding, and the upper surface and the side surface of the stacked body on the oxide superconducting layer side To deposit a stabilization layer on Thus, the oxide superconducting layer and the second metal layer are electrically connected.

Furthermore, the tape-shaped oxide superconductor substrate of the present invention joins the first metal layer and the second metal layer as the core material, and the first metal layer is mechanical strength of the second metal layer. It is formed of a nickel-based alloy or stainless steel containing one or more additional elements selected from tungsten, molybdenum, chromium, iron, cobalt, vanadium, and manganese into larger, non-oriented, non-magnetic nickel, The second metal layer is formed of copper, silver, gold, aluminum having a thermal conductivity of 100 W / m · K or higher or an alloy containing these as a main material in a temperature range of 100 to 300 K, and the first metal layer And the second metal layer are subjected to heat treatment after surface activation bonding to be bonded via the bonding layer .

In the above tape-shaped oxide superconductor, the first metal layer is formed by a nickel-based alloy or stainless steel, for example, the first metal layer is tungsten nickel, molybdenum, chromium, iron, cobalt, vanadium, manganese It is formed of a nickel-based alloy containing one or more selected additive elements.

The second metal layer functions as a heat radiating member and a connecting member, and has a thermal conductivity of 100 W / m · as a material having a high thermal conductivity and a low electrical resistance in a temperature range of 100 to 300 K. Copper, silver, gold, aluminum of K or more, or a copper base alloy, silver base alloy, gold base alloy or aluminum base alloy containing these as main materials is used.

More first metal layer and second metal layer are bonded via the bonding layer by heat treatment after surface activation bonding. Thereby, a 1st metal layer and a 2nd metal layer can be joined firmly. This bonding method is a well-known process and is generally called surface activated bonding. A material whose surface smoothness is Ra = 5 nm or less by subjecting the surface to electropolishing in advance is subjected to high vacuum ( In an atmosphere of 10 ⁻⁸ Pa), an argon ion beam (or hydrogen radicals may be used) is applied and pressed and bonded at a pressure of 10 MPa (see, Materia, Vol. 35, No. 5, 1996).

  The intermediate layer on the first metal layer is preferably formed by the IBAD process described above. By forming an intermediate layer by the IBAD process, an intermediate layer that has a fine crystal grain size and high orientation on a high-strength tape-like Ni substrate, etc., and suppresses the reaction with the elements constituting the superconductor. Layers can be formed directly.

  On the other hand, in the tape-shaped oxide superconductor according to the present invention, the oxide superconducting layer and the stabilizing layer on the upper surface thereof are preferably divided into a plurality of current paths along the tape axial direction. In the present invention, the second metal layer made of a material having high thermal conductivity and low electrical resistance is bonded to the surface opposite to the intermediate layer side of the first metal layer having high mechanical strength as the core material. Therefore, thinning of the superconducting layer by laser processing becomes easy, and the hysteresis loss due to the magnetic flux pinning phenomenon can be reduced by dividing the oxide superconducting layer and the stabilizing layer into a plurality of current paths. .

  In the tape-shaped oxide superconductor of the present invention, the intermediate layer side of the first metal layer having high mechanical strength in which the second metal layer made of a material having high thermal conductivity and low electrical resistance serves as a core material Since it is bonded to the surface opposite to the surface, there is an advantage that heat dissipation is excellent and the superconducting layer can be easily thinned by laser processing.

  In the tape-shaped oxide superconductor of the present invention, a stabilization layer is deposited on the upper surface and the side surface of the oxide superconducting layer side of the laminate in which the intermediate layer and the oxide superconducting layer are formed on the first metal layer. As a result, when the superconducting layer and the second metal layer made of a material having low electrical resistance are electrically connected to form a coil, it is possible to easily apply a current from an external power source to the superconductor. Have.

  Furthermore, the substrate of the present invention is suitable for the production of the tape-shaped oxide superconductor described above, and the first metal layer and the second metal layer are subjected to a heat treatment after surface activation bonding to form a bonding layer. By joining via, there is an advantage of excellent mechanical strength and joining strength.

  As shown in FIG. 1, the tape-shaped oxide superconductor 10 of the present invention is composed of a first metal layer 11 serving as a core material and copper, silver, gold, aluminum, or an alloy containing these as main materials. A three-layered intermediate layer made of an inorganic material biaxially oriented on the first metal layer 11 of the substrate 13 joined to the second metal layer 12 formed of a material having high conductivity and low electrical resistance. 14 and a YBCO superconducting layer 15 are laminated, and a vapor deposition layer of an Ag stabilizing layer 16 is formed on the YBCO superconducting layer 15 of the laminated body.

  The first metal layer 11 is made of a nickel-based alloy containing nickel having a mechanical strength higher than that of the second metal layer and one or more additive elements selected from tungsten, molybdenum, chromium, iron, cobalt, vanadium, and manganese. The first metal layer 11 and the second metal layer 12 are firmly bonded via the bonding layer by performing a heat treatment after the surface activation bonding, The mechanical strength and bonding strength of the substrate 13 are improved.

  The heat treatment after the surface activation bonding described above is performed in order to suppress the influence of the interface due to the fine amorphous layer and the fine crystal grains formed between the bonded layers and to form a uniform and strong bonding layer by element diffusion. Is done. The heat treatment in this case is performed in a reducing atmosphere or an inert atmosphere.

The intermediate layer 14 on the first metal layer 11 is formed by depositing a Gd ₂ Zr ₂ O ₇ layer 14a and a CeO ₂ layer 14b by an IBAD process, and depositing a CeO ₂ layer 14c thereon by a sputtering method. On the CeO ₂ layer 14c, the YBCO superconducting layer 15 is laminated by the TFA-MOD method, and the Ag stabilizing layer 16 is laminated by the vapor deposition method.

  The other tape-shaped oxide superconductor 20 of the present invention shown in FIG. 2 basically has the same structure as the tape-shaped oxide superconductor 10 of FIG. The same reference numerals are used.

  The tape-shaped oxide superconductor 20 includes an intermediate layer 14, a YBCO superconducting layer 15 and an Ag stabilizing layer on the first metal layer 11 of the substrate 13 in which the first metal layer 11 and the second metal layer 12 are joined. 1 is the same as in FIG. 1 except that the Ag stabilizing layer 16 is deposited on the top and side surfaces of the laminate, which is the top surface of the YBCO superconducting layer 15, by vapor deposition. Thus, the YBCO superconducting layer 15 and the second metal layer 12 are electrically connected.

  The tape-shaped oxide superconductors 10 and 20 described above are intermediate between the first metal layer 11 having a high mechanical strength in which the second metal layer made of a material having a high thermal conductivity and a low electric resistance serves as a core material. Since it is bonded to the surface opposite to the layer side, it has excellent heat dissipation, and the superconducting layer can be easily thinned by laser processing.

  Further, when a superconducting coil is manufactured using the tape-shaped oxide superconductor 20 described above, for example, in order to prevent a decrease in Ic due to additional strain, the pancake (or double pancake) is formed with the Ag stabilizing layer 16 inside. Since a current can be applied to the superconducting layer via the outer second metal layer when adopting a structure wound in the shape of a cake, it is easy to apply a current from the external power source to the superconducting coil. Thus, the design of the electrode connection portion can be simplified.

  Examples of the present invention will be described below.

  Examples of the present invention and comparative examples will be described below.

Example As shown in FIG. 2, after a 100 μm ^t Cu tape 12 was bonded to one side of a non-oriented nonmagnetic 100 μm ^t hastelloy tape 11 by a surface activated bonding process, Ar— A substrate 13 was prepared by performing a heat treatment at 500 ° C. for 3 hours in a reducing atmosphere of 4% H ₂ to form a diffusion layer, that is, a bonding layer having a thickness of 1 μm or less at the adhesion interface.

A 400 nm thick Gd ₂ Zr ₂ O ₇ layer 14a and a 1.0 μm thick CeO ₂ layer 14b are formed on the Hastelloy tape 11 of the substrate 13 by an IBAD process, and a 150 nm thick CeO ₂ layer is formed thereon. _{After the two} layers 14c were formed by the high frequency sputtering method, the YBCO layer 15 was further formed thereon.

  The YBCO layer 15 was formed by the following method. First, dip coating a mixed solution in which Y-TFA salt, Ba-TFA salt and Cu naphthenate were mixed in 2-octanone so that the molar ratio of Y: Ba: Cu was 1: 1.5: 3. After coating on the intermediate layer using a method, heating to a maximum heating temperature of 380 ° C. in an oxygen gas atmosphere with a water vapor mole fraction of 2.0% and 760 Torr, forming a calcined film by furnace cooling to room temperature, After repeating this process to form a plurality of calcined films, crystallization is performed under firing conditions of a maximum heating temperature of 700 to 780 ° C. in an oxygen-argon gas atmosphere with a water vapor partial pressure of less than 7.5% and a furnace pressure of less than 760 Torr A YBCO layer 15 was formed by heat treatment, that is, heat treatment for generating a superconductor. The thickness of the YBCO layer formed as described above was 1.5 μm.

Next, the upper surface of the YBCO layer 15, the side surface of the substrate 13 (side surfaces of the Hastelloy tape 11 and the Cu tape 12), the side surface of the intermediate layer 14 (the side surfaces of the Gd ₂ Zr ₂ O ₇ layer 14a, the CeO ₂ layer 14b, and the CeO ₂ layer 14c) ) after forming the deposition layer 16 having a thickness of 20μm of Ag, the stabilizing layer 16 of Ag by YBCO layer 15 and deposition is divided into a plurality in the axial direction of the tape by laser processing.

  After electrically connecting the divided current paths at both ends of the tape-shaped oxide superconducting wire 20, Ic was measured, and as a result, a value of 150 A was shown in the self magnetic field (77K).

  Moreover, as a result of producing a superconducting coil by using the above-described tape-shaped oxide superconducting wire 20 and winding it in a double pancake shape with the Cu tape 12 outside, a current was applied to the Cu tape 12 from an external power source. There was no hindrance to the application of current.

The IBAD process on a Hastelloy tape 11 having a thickness of 100 [mu] m ^t of the non-magnetic comparative example non-oriented, to form a CeO ₂ layer of _Gd 2 _Zr 2 _{O 7} layer and the thickness 1.0μm thick 400 nm, on the After forming a 150 nm thick CeO ₂ layer by high frequency sputtering, a YBCO layer was further formed thereon.

  The YBCO layer was formed by the same method as in the example. The Cu tape was joined to the surface of this YBCO layer with solder, and an attempt was made to divide the YBCO layer into a plurality along the axial direction of the tape. However, since the surface of the YBCO layer was oxidized, the axial direction of the tape It was not possible to bond them over a long distance, and laser processing was impossible.

  The tape-shaped oxide superconductor according to the present invention can be used as an oxide superconductor suitable for use in power devices such as power transmission cables and power storage systems and power devices such as motors. The tape-shaped oxide superconductor substrate according to is suitable for use in such a superconductor.

It is sectional drawing perpendicular | vertical to the axial direction of the tape which shows one Example of the tape-shaped oxide superconductor of this invention. It is sectional drawing perpendicular | vertical to the axial direction of the tape which shows one Example of the tape-shaped oxide superconductor of this invention. It is a perspective view which shows the state which divides | segments a tape-shaped oxide superconductor along an electric current path.

Explanation of symbols

10, 20, 30 Tape-shaped oxide superconductor 11 First metal layer 12 Second metal layer 13 Substrate 14 Intermediate layer 15, 34 YBCO superconducting layer 15
16, 35 Ag stabilizing layer 31 Hastelloy 32 Gd—Zr—O intermediate layer 33 CeO ₂ intermediate layer

Claims (8)

One or more intermediate layers made of a biaxially oriented inorganic material and oxide superconductivity on the first metal layer of the substrate bonded with the first metal layer and the second metal layer as the core material In the oxide superconductor composed of a laminate in which a layer is formed, each of the first metal layer and the second metal layer is larger than the mechanical strength of the second metal layer and is non-oriented and nonmagnetic. nickel-based alloy or stainless steel, and in a temperature range of 100～300K, thermal conductivity greater than 100W / m · K copper, silver, gold, an aluminum or an alloy containing these as a main material Rutotomoni, the first A tape-shaped oxide superconductor , wherein a metal layer and the second metal layer are bonded via a bonding layer by performing a heat treatment after surface activation bonding . One or more intermediate layers made of a biaxially oriented inorganic material and oxide superconductivity on the first metal layer of the substrate bonded with the first metal layer and the second metal layer as the core material In the oxide superconductor composed of a laminate in which a layer is formed, each of the first metal layer and the second metal layer is larger than the mechanical strength of the second metal layer and is non-oriented and nonmagnetic. A nickel-based alloy or stainless steel, and copper, silver, gold, aluminum or an alloy containing these as main materials in a temperature range of 100 to 300 K and having a thermal conductivity of 100 W / m · K or more , and the first metal bonded via a bonding layer by heat treatment after surface activation bonding the the layer second metal layer, depositing a stabilizing layer on the upper surface and the side surface of the oxide superconducting layer side of the laminate The oxide A tape-shaped oxide superconductor, wherein a superconducting layer and the second metal layer are electrically connected. The first metal layer is nickel tungsten, molybdenum, chromium, iron, cobalt, vanadium, according to claim 1 or 2, characterized in that it consists of a nickel-based alloy containing one or more additive elements selected from manganese Tape-shaped oxide superconductor. The tape-shaped oxide superconductor according to any one of claims 1 to 3 , wherein the intermediate layer on the first metal layer is formed by an IBAD process. The tape-shaped oxide superconductor according to any one of claims 1 to 4 , wherein the oxide superconducting layer on the intermediate layer is formed by a TFA-MOD method. Stabilizing layer of the oxide superconducting layer and the upper surface thereof, the tape-shaped oxide superconductor that claims 2 to 5 any one of claims, characterized in that is divided into a plurality of current paths along the tape axis . A substrate used for manufacturing a tape-shaped oxide superconductor, wherein the substrate joins a first metal layer and a second metal layer as a core material, and the first metal layer is bonded to the first metal layer. Nickel-based alloy containing one or more additional elements selected from tungsten, molybdenum, chromium, iron, cobalt, vanadium, and manganese in non-oriented non-magnetic nickel that is greater than the mechanical strength of the second metal layer or made of a material consisting of stainless steel, an alloy containing in a temperature range of 100~300K the second metal layer, thermal conductivity of 100W / m · K or more copper, silver, gold, aluminum or these as a main material and forming a tape-like acid, characterized in that the bonding via the bonding layer by heat treatment after surface activation bonding the second metal layer and the first metal layer Things superconductor substrate. 8. The tape-shaped oxide superconductor according to claim 7 , wherein the substrate has one or more intermediate layers made of a biaxially oriented inorganic material formed on the first metal layer. substrate.

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