JP2008147012A - Manufacturing method of oxide superconducting wire, and superconducting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method capable of achieving an organization where a superconducting crystal is highly oriented in an oxide superconducting wire, and a uniform superconducting filament shape, and thereby manufacturing an oxide superconducting wire having a high critical current value. <P>SOLUTION: This manufacturing method of an oxide superconducting wire comprises: a process of filling a metal pipe with precursor powder of a (Bi, Pb) 2223 superconductor; a process of plastically processing the metal pipe filled with the precursor powder; and a heat treatment process of heat-treating a wire after the plastically processing process. The manufacturing method is characterized by compressively molding the precursor powder into a plate-like shape, and thereafter filling the metal pipe with the plate-like precursor powder, and increases a critical current value. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention is used in (Bi, Pb) ₂ Sr ₂ Ca ₂ Cu ₃ O _{10 ± δ} (δ is about 0.1) used in superconducting application equipment such as superconducting cables, superconducting coils, superconducting transformers, and superconducting power storage devices. Number: The manufacturing method of an oxide superconducting wire containing a phase (hereinafter referred to as (Bi, Pb) 2223), and more specifically, a manufacturing method of an oxide superconducting wire for the purpose of improving the critical current value of the (Bi, Pb) 2223 superconducting wire About.

  An oxide superconducting wire mainly composed of (Bi, Pb) 2223 phase produced by a metal sheath method has a high critical temperature and a useful value showing a high critical current value even under relatively simple cooling such as liquid nitrogen temperature. (For example, refer nonpatent literature 1). Therefore, if further improvement in performance (critical current value) is realized, the range of practical use is expanded.

  In addition, it is considered that by using the (Bi, Pb) 2223 superconducting wire, it is possible to reduce energy loss far more than when using a conventional normal conductor. Therefore, development of superconducting application equipment such as a superconducting cable, a superconducting coil, a superconducting transformer, a superconducting power storage device using a (Bi, Pb) 2223 superconducting material wire as a conductor is being promoted at the same time.

As a method for increasing the critical current value of a superconducting wire, a method of sintering a (Bi, Pb) 2223 series superconducting wire in a pressurized atmosphere is employed (see Patent Document 1 and Non-Patent Document 1). . As a result, the critical current value at the liquid nitrogen temperature is improved from about 100 A to 120 A class.
JP 2002-093252 A SEI Technical Review, March 2004, No. 164, p36-42

  The effect of improving the critical current value is also recognized by the above technique. However, considering the needs from the future market, further increase of the critical current value is desired. Therefore, an object of the present invention is to provide a method for producing an oxide superconducting wire having a higher critical current value.

  The present inventors have found a method for producing a superconducting wire that improves the critical current value by characterizing the form of the precursor powder during the production process of the (Bi, Pb) 2223 wire. Specifically, it is as follows.

  The present invention includes a step of filling a metal tube with a precursor powder of (Bi, Pb) 2223 superconductor, a step of plastically processing the metal tube filled with the precursor powder, and a wire rod after the plastic processing step. An oxide superconducting wire manufacturing method comprising a heat treatment step for heat treatment, wherein the precursor powder is compression-molded into a plate shape, and then the plate-like precursor powder is filled into a metal tube It is a manufacturing method of a superconducting wire.

  In the present invention, it is preferable to fill the metal pipe with the plate precursor powder so that the ab plane direction of the superconducting crystal contained in the plate precursor is aligned with the longitudinal direction of the metal pipe.

  In the present invention, the compression molding is preferably performed by rolling.

  In the present invention, the metal powder is preferably filled after heat-treating the compression-molded precursor powder.

  In the present invention, the precursor powder of the (Bi, Pb) 2223 superconductor preferably has a tetragonal Bi2212 phase as a main phase.

  Moreover, this invention is a superconducting apparatus which contains the oxide superconducting wire manufactured by the manufacturing method in any one of said as a conductor.

  According to the production method of the present invention, a (Bi, Pb) 2223 oxide superconducting wire having a high critical current value can be obtained. Moreover, by using the oxide superconducting wire of the present invention as a conductor, it is possible to realize superconducting equipment such as a high-performance superconducting cable, a superconducting coil, a superconducting transformer, and a superconducting power storage device.

(Embodiment)
FIG. 1 is a partial cross-sectional perspective view schematically showing the configuration of an oxide superconducting wire. For example, a multi-core oxide superconducting wire will be described with reference to FIG. The oxide superconducting wire 11 has a plurality of oxide superconductor filaments 12 extending in the longitudinal direction and a sheath portion 13 covering them. The material of each of the plurality of oxide superconductor filaments 12 is preferably a Bi—Pb—Sr—Ca—Cu—O based composition, and the atomic ratio of (Bi, Pb): Sr: Ca: Cu is particularly about 2. The material including the (Bi, Pb) 2223 phase expressed by the ratio of 2: 2: 3 is optimal. The material of the sheath part 13 is comprised from metals, such as silver and a silver alloy, for example.

  Next, the manufacturing method of said oxide superconducting wire is demonstrated.

  FIG. 2 is a flowchart showing a manufacturing process of the oxide superconducting wire in the embodiment of the present invention. 3 to 7 are diagrams showing each step of FIG.

Referring to FIGS. 2 and 3, first, oxide superconductor precursor powder 31 is filled into metal tube 34 (step S1). This oxide superconductor precursor powder 31 has, for example, a (Bi, Pb) ₂ Sr ₂ Ca ₁ Cu ₂ O _{8 ± δ} (δ is a number close to 0.1: hereinafter referred to as (Bi, Pb) 2212) phase. And Bi ₂ Sr ₂ Ca ₁ Cu ₂ O _{8 ± δ} (δ is a number close to 0.1; hereinafter referred to as Bi2212) phase as a main phase, superconducting phase 32 such as (Bi, Pb) 2223 phase, alkaline earth oxidation (For example, (Ca, Sr) CuO ₂ , (Ca, Sr) ₂ CuO ₃ , (Ca, Sr) ₁₄ Cu ₂₄ O ₄₁ etc.), Pb oxide (for example, Ca ₂ PbO ₄ , (Bi, Pb)) ₃ Sr ₂ Ca ₂ Cu ₁ O _z ) or the like, and is made of a material including the non-superconducting phase 33. Note that silver or a silver alloy is preferably used as the metal tube 34. This is to prevent compositional deviation of the precursor powder due to the reaction between the precursor powder and the metal tube to form a compound. The present invention is characterized by the form of the precursor powder at the time of filling. This feature and effect will be described later.

  Next, as shown in FIG. 2 and FIG. 4, the metal tube 41 filled with the precursor powder is drawn to a desired diameter, and the precursor 42 is used as a core material and coated with a metal such as silver. The core wire 43 is produced (step S2).

  Next, as shown in FIGS. 2 and 5, a large number of single core wires 51 are bundled and fitted into a metal tube 52 made of, for example, silver (multi-core fitting: step S3). Thereby, the multi-core structure material which has many precursor powders as a core material is obtained.

  Next, as shown in FIGS. 2 and 6, the multi-core structural member 61 is drawn to a desired diameter, the precursor powder 62 is embedded in the metal sheath portion 63, and the cross-sectional shape is circular or polygonal. An isotropic multi-core bus 64 is produced (step S4). Thereby, an isotropic multi-core bus 64 having a form in which the precursor powder 62 of the oxide superconducting wire is covered with a metal is obtained.

  Next, as shown in FIGS. 2 and 7, the isotropic multi-core bus bar 71 is rolled (primary rolling: step S5). Thereby, the tape-shaped precursor wire 72 is obtained.

  Next, the tape-shaped precursor wire is heat-treated (primary heat treatment: step S6). This heat treatment is performed at a temperature of about 830 ° C., for example, under atmospheric pressure or in a pressurized atmosphere of 1 MPa to 50 MPa. The target (Bi, Pb) 2223 superconducting phase is generated from the precursor powder by heat treatment.

  Thereafter, the wire is rolled again (secondary rolling: step S7). Thus, by performing secondary rolling, voids generated by the primary heat treatment are removed.

  Subsequently, for example, the wire is heat-treated at a temperature of 830 ° C. (secondary heat treatment: step S8). Also at this time, heat treatment is performed under atmospheric pressure or in a pressurized atmosphere. The oxide superconducting wire shown in FIG. 1 is obtained by the above manufacturing process.

  Hereinafter, details of the precursor powder in step S1 which is a feature of the present invention will be described. In order to achieve a high critical current density in an oxide superconducting wire, high orientation of superconducting crystal grains is important. For this purpose, rolling in step S6 is performed. In this method, the wire is deformed in a uniaxial direction into a tape shape, and the ab plane direction of the (Bi, Pb) 2223 superconducting crystal is oriented so as to be parallel to the tape surface. Although most of the superconducting crystal grains can be oriented by the rolling process as described above, the orientation of the central crystal grains separated from the metal coating in each filament, where external force due to rolling is difficult to work, is insufficiently oriented. There are many cases. In order to solve this, if the orientation is performed at the time of wire drawing, or if the precursor powder that has been oriented since filling is used, the center portion of the filament is easily oriented.

  Therefore, if the precursor powder is compression-molded into a plate shape as in the present invention, the precursor powder can be filled in a form that is easily oriented by wire drawing. As a compression molding method, a plate-like precursor powder can be obtained by using uniaxial pressing or rolling. The thickness of the plate is preferably about 1 mm or less. The reason why the thickness is set to about 1 mm or less is to make it easy to obtain a form oriented to the center as in the effect during wire rolling. In such a form, (Bi, Pb) 2212 and Bi2212 crystal grains are present in the plate-like precursor powder so that the ab plane direction is parallel to the plate surface. If the plate thickness is too large, it is difficult to orient the center part.

  FIG. 8 is a diagram schematically showing the steps from precursor molding to filling according to the present invention. Precursor powder 31 containing superconducting phase 32 and non-superconducting phase 33 is passed between rolling rolls 81 to obtain plate-like precursor 82. If this plate-like precursor 82 can be filled in a metal tube as it is, it may be used as it is, or may be divided and used as a plate-like chip 83. At this time, it is important that the plate precursor 82 or the plate chip 83 to be filled has a shape in which a direction longer than the plate thickness (hereinafter referred to as a longitudinal direction) exists. The ab plane direction of the superconducting crystal faces this longitudinal direction. The internal structure of the plate-like precursor will be described later.

  FIG. 9 is a partial cross-sectional perspective view schematically showing the inside of the plate-like precursor powder. In FIG. 9, the broken line is a line representing the outline of the plate-like precursor 82 and the plate-like chip 83. The cross section is depicted with a gap so that the superconducting phase 32 is oriented and the non-superconducting phase 33 can be easily recognized, but is actually packed without a gap. As shown in FIG. 9, in the plate-like precursor 82 and the plate-like chip 83, the ab surface direction of the superconducting phase 32 is oriented so as to be substantially parallel to the plate surface.

  The effect of filling the metal tube with the precursor powder molded into a plate shape will be described below. First, since it is compression molded, the density at the time of filling increases to some extent. The precursor powder made into a plate shape is pulverized into a few mm square and a thickness of about 1 mm and filled. When filled in this way, gaps are formed to some extent between the plate-like precursors, but the density can be made higher than when filling the precursor powder that is not compressed into a plate-like shape. When filling the uncompressed precursor powder, the density can only be increased to approximately 20% of the limit value. According to this method, it can be increased from 30% to 40%.

  Having this gap is one factor that promotes orientation in wire drawing. FIG. 10 is a diagram schematically showing the orientation in the wire drawing process. As described above, the precursor powder flows and the density increases so as to fill the gap by wire drawing. At the time of wire drawing, the plate-like precursor 82 in the metal tube 34 is subjected to an external force from the outer peripheral portion toward the center when passing through the die 101 portion where the diameter is reduced. Therefore, the plate-like precursor 82 falls down so that its length direction is perpendicular to the external force direction (parallel to the wire drawing direction). That is, it is processed so that the ab plane direction of the superconducting crystal in the plate-like precursor 82 is parallel to the longitudinal direction of the drawn wire. Such an effect is induced because the precursor is plate-shaped and has a shape with a direction longer than the plate thickness.

  A more preferable filling method is such that the ab surface direction of the superconducting crystal ((Bi, Pb) 2212 or Bi2212 crystal) contained in the plate precursor is aligned with the longitudinal direction of the metal tube from the time of filling. Filling the body with metal tubes. As described above, an oriented state is obtained from the filling stage, which is more effective. An example of the filling method will be described below.

  FIG. 11 is a diagram schematically showing steps from precursor molding to filling for aligning the ab plane direction of the superconducting crystal contained in the plate-like precursor during filling. Precursor powder 31 containing superconducting phase 32 and non-superconducting phase 33 is passed between rolling rolls 81 to obtain plate-like precursor 82. This plate-like precursor 82 may be used as it is, or may be divided and used as a plate-like chip 83. At this time, it is important that the plate-like precursor 82 or the plate-like chip 83 to be filled has a shape that is longer than the plate thickness and has a direction having a length that is at least twice the inner diameter of the metal tube 34 to be filled. is there. Since the plate-like precursor 82 and the plate-like chip 83 formed as described above have a size that is at least twice the inner diameter of the metal tube, the longitudinal direction of the plate-like precursor 82 and the plate-like chip 83 in the metal tube 34 Will peel in the same direction as the longitudinal direction of the metal tube 34. The filling method is not limited to the above as long as the longitudinal direction of the plate-like precursor 82 and the plate-like chip 83 can be filled so as not to fall in the metal tube 34.

  According to the present invention, it is possible to obtain a metal tube in which the precursor is oriented at the time of wire drawing or filling, so that a superconducting wire having a high critical current value can be obtained because the crystals in the superconducting wire can be more oriented. realizable.

  According to the present invention, another effect can be obtained by obtaining an oriented metal tube even after wire drawing. In other words, a high critical current value can be obtained to some extent without rolling. As described above, in the conventional method, rolling is performed in order to orient the crystal grains in the precursor powder. By carrying out the rolling process, the final cross-sectional shape of the wire has to be substantially tape-like or substantially rectangular. However, the tape-shaped wire is not suitable for forming a conductor (twisted conductor) that is twisted together to form a spiral. Therefore, a wire having an isotropic sectional shape such as a circle or a hexagon may be effective. Therefore, by using the present invention, it is possible to produce a wire having an isotropic shape such as a circle or a hexagonal cross section having a relatively high critical current value.

  A rolling process is more suitable for the compression molding of the precursor powder into a plate shape. This is because a plate-like precursor having the same thickness can always be obtained by setting a roll gap during rolling, and a plate-like chip having a constant size can be produced during division. By having a certain size, it is possible to perform filling that facilitates aligning the direction of the plate-shaped chip.

  In order to further increase the degree of orientation, it is effective to heat-treat the plate precursor. When the plate-like precursor is heat-treated at a temperature of about 700 ° C. to 800 ° C. for about 1 to 5 hours in an atmosphere containing oxygen, (Bi, Pb) 2212 and Bi2212 crystal grains contained in the precursor are enlarged. Such enlarged crystal grains are more likely to fall by plastic working with the ab plane direction oriented in the longitudinal direction of the wire.

  Furthermore, the degree of crystal grain growth in this heat treatment is affected by the components constituting the precursor powder. In the precursor powder to be filled, two 2212 phases of (Bi, Pb) 2212 phase which is orthorhombic and Bi2212 phase which is tetragonal are mixed. These ratios can be adjusted at the stage of preparing the precursor powder. The Bi 2212 phase absorbs Pb from the surrounding Pb compound and can replace the (Bi, Pb) 2212 phase. When this reaction occurs, a very large (Bi, Pb) 2212 phase is easily generated from the Bi 2212 phase. Therefore, it is preferable that the precursor powder has a tetragonal Bi2212 phase as a main phase, and it is more effective to heat-treat it.

  By filling the metal tube with the oriented precursor powder as described above, it is isotropic with a highly oriented structure and a uniform filament shape even after plastic processing of wire drawing and rolling. Multi-core bus bars and tape-shaped precursor wires are obtained. When the heat treatment process after step S6 is performed on the basis of this highly oriented wire, a superconducting wire having a high critical current value can be manufactured.

  Moreover, since the superconducting device according to the present invention is composed of the superconducting wire having a high critical current value as described above, it has excellent superconducting characteristics. Here, the superconducting device is not particularly limited as long as it includes the superconducting wire, and examples thereof include a superconducting cable, a superconducting coil, a superconducting magnet, a superconducting transformer, and a superconducting power storage device. For example, in superconducting cables and superconducting transformers used in AC applications, the loss in operating current value decreases due to the improvement of the critical current value. On the other hand, the maximum generated magnetic field and the maximum stored energy are greatly increased in devices mainly using DC, such as a superconducting magnet and a superconducting power storage device.

  FIG. 12 is a perspective view showing the internal structure of a superconducting cable as an example. An oxide superconducting wire 127 according to the present invention is spirally wound around the former 121 to form a conductor layer 122. In addition, an insulating layer 123 is disposed, and an oxide superconducting wire 127 is spirally wound around the outer periphery thereof to form a magnetic shield layer 124. They are covered with a heat insulating layer 125 and accommodated in the outer tube 126.

  FIG. 13 is a schematic diagram showing an example of a typical superconducting magnet. The oxide superconducting wire according to the present invention is wound in a pancake shape to form a coil 131. A plurality of the coils 131 are electrically connected according to the purpose. When a current is passed through the electrode 132, a magnetic field is generated in the coil 131. In addition, if the electrodes 132 are coupled by a permanent current switch 133 made of an oxide superconducting wire and excited to a target magnetic field, the permanent current switch 133 is turned on, and then the coil 131-permanent current switch 133 enters the loop. Permanent current flows. This current hardly attenuates and can store energy as a magnetic field. If necessary, the current can be taken out by turning off the permanent current switch 133 so that the current flows to the electrode 132 side. If used in this way, it can be used as a superconducting power storage device.

  FIG. 14 is a schematic diagram showing an example of a typical superconducting transformer. A primary superconducting coil 141 and a secondary superconducting coil 142 are magnetically coupled via a core 145 made of iron or the like. An alternating current is applied to the primary superconducting coil 141 from the primary electrode 143. The alternating current generates an alternating magnetic field in the primary superconducting coil 141, and a magnetic field is also induced in the secondary superconducting coil 142 through the core 145. An AC voltage is induced in the secondary superconducting coil 142 induced by the induced AC magnetic field, and is taken out by the secondary electrode 144. By changing the number of turns of the primary superconducting coil 141 and the secondary superconducting coil 144, it is possible to generate a voltage different from the primary side on the secondary side.

(Example)
Hereinafter, based on an Example, this invention is demonstrated further more concretely.

Raw material powder (Bi ₂ O ₃ , PbO, SrCO ₃ , CaCO ₃ , CuO) is in a ratio of Bi: Pb: Sr: Ca: Cu = 1.8: 0.3: 1.9: 2.0: 3.0 The mixture is subjected to heat treatment at 700 ° C. for 8 hours, pulverization, heat treatment at 800 ° C. for 10 hours, pulverization, heat treatment at 820 ° C. for 4 hours, and pulverization in the air to obtain a precursor powder. In addition, by injecting a nitric acid aqueous solution in which five types of raw material powders are dissolved into a heated furnace, the water in the particles of the metal nitrate aqueous solution evaporates, the thermal decomposition of the nitrate, and the reaction and synthesis of metal oxides. Precursor powder can also be produced by a spray pyrolysis method that instantly raises. The precursor powder thus produced is a powder mainly composed of the Bi2212 phase. In addition, a part of the heat treatment conditions is changed to obtain a precursor powder in which the (Bi, Pb) 2212 phase is the main phase.

  The precursor powder in which the Bi2212 phase is the main phase is divided into two groups, and one is used as it is without compression molding (precursor 1: comparative example). The other is roll-rolled and pressed into a plate having a thickness of about 1.0 mm, and then a part is divided into plate-like chips having a length of about 5 mm × width of about 2 to 5 mm. (Precursor 2: Example). The remainder is divided into plate-like chips having a length of about 50 mm × width of about 2 to 5 mm (precursor 3: example). Further, a part of the precursor 3 is heat-treated for 2 hours under conditions of a temperature of 760 ° C., a total pressure of 1 atm (0.1 MPa), and an oxygen partial pressure of 0.0001 MPa (precursor 4: example). The precursor powder in which the (Bi, Pb) 2212 phase is the main phase is used after being subjected to the same steps as the precursor 4 (precursor 5: example).

  Each precursor prepared as described above is filled in a silver pipe having an outer diameter of 25 mm and an inner diameter of 22 mm. In particular, the precursor 2 is filled without aligning the direction of the plate-shaped tips, and the precursors 3, 4 and 5 are filled so that the longitudinal direction of each tip is aligned with the longitudinal direction of the metal tube. At this stage, in order to know how much the precursor powder is filled, the weight of the silver pipe is measured, and the filling density is calculated from the inner volume of the silver pipe. The results are shown in Table 1. Thereafter, the filled silver pipe is drawn to a diameter of 2.4 mm to produce a single core wire. 55 single-core wires are bundled and inserted into a silver pipe having an outer diameter of 25 mm and an inner diameter of 22 mm, and drawn to a diameter of 1.5 mm to obtain a multi-core (55-core) wire. In this way, five kinds of wires filled with different precursors are obtained. (Wire 1: Precursor 1: Comparative Example), (Wire 2: Precursor 2: Example), (Wire 3: Precursor 3: Example), (Wire 4: Precursor 4: Example), (Wire 5: Precursor 5: Example).

  Five types of multi-core wires are rolled and processed into a tape-like wire having a thickness of 0.25 mm. The obtained tape-shaped wire is subjected to primary heat treatment at 830 ° C. for 30 to 50 hours in an atmosphere having a total pressure of 1 atm (0.1 MPa) and an oxygen partial pressure of 8 kPa.

  The tape-shaped wire after the primary heat treatment is re-rolled to a thickness of 0.23 mm. The tape-shaped wire after re-rolling is subjected to a secondary heat treatment at 830 ° C. for 50 to 100 hours in a pressurized atmosphere containing an oxygen partial pressure of 8 kPa and a total pressure of 30 MPa.

The critical current value (Ic) of the produced wire was measured. For the critical current value, a current-voltage curve was measured by the four probe method at a temperature of 77 K and in a zero magnetic field, and a current that generates a voltage of 1 × 10 ⁻⁶ V per 1 cm of wire was defined as the critical current value. The results are shown in Table 1.

  Further, as an evaluation of the orientation of the (Bi, Pb) 2223 crystal, the following average misalignment angle α is measured. The average misalignment angle α is the average angle formed between the surface formed by the a-axis and the b-axis of each (Bi, Pb) 2223 crystal and the tape surface (width × length surface) of the wire. Say. The smaller the average misorientation angle α of (Bi, Pb) 2223 crystal, the higher the orientation of (Bi, Pb) 2223 crystal. The average misorientation angle α of the (Bi, Pb) 2223 crystal is calculated as ½ of the half width of the diffraction peak derived from the (0,0,24) plane of the (Bi, Pb) 2223 layer. α is shown in Table 1.

  In the wire 1 (comparative example), the precursor powder is not compression-molded. Wires 2 to 5 (Examples) are compression molded. When the wires 2 to 5 and the wire 1 are compared, the wires 2 to 5 have better results in any of the packing density, the average misalignment angle (α), and the critical current value. In particular, a large difference appears in the packing density. From comparison between the wire 2 and the wire 3, it can be seen that a higher critical current value can be obtained by filling the metal pipe with the orientation of the precursors aligned. This is considered due to the difference in the degree of orientation (α).

  From comparison between the wires 3 and 4, it can be seen that a higher critical current value can be obtained by heat-treating the precursor. It is considered that this is also caused by the difference in the degree of orientation (α) and the difference in packing density as described above. Similarly, when the heat treatment is performed, if the main phase of the precursor powder is changed (comparison between the wires 4 and 5), it is understood that the Bi2212 phase is more effective.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a partial section perspective view showing typically the composition of an oxide superconducting wire. It is a flowchart which shows the manufacturing process of the oxide superconducting wire in embodiment of this invention. It is a figure which shows S1 step in FIG. It is a figure which shows S2 step in FIG. It is a figure which shows S3 step in FIG. It is a figure which shows S4 step in FIG. It is a figure which shows S5 step in FIG. It is the figure which represented typically the process from the precursor shaping | molding of this invention to filling. FIG. 3 is a partial cross-sectional perspective view schematically showing the inside of a plate-like precursor powder. It is the figure which showed typically a mode that it orientated in a wire drawing process. It is the figure which represented typically the process from precursor shaping | molding for aligning the ab surface direction of the superconducting crystal contained in a plate-shaped precursor at the time of filling. It is a perspective view which shows the internal structure of the superconducting cable as an example. It is a schematic diagram which shows the example of a typical superconducting magnet. It is a schematic diagram which shows the example of a typical superconducting transformer.

Explanation of symbols

  11 Oxide Superconducting Wire, 12 Oxide Superconducting Filament, 13 Sheath Part, 31 Precursor Powder, 32 Superconducting Phase, 33 Non-Superconducting Phase, 34 Metal Tube 41 Metal Tube Filled with Precursor Powder, 42 Precursor, 43 Single Core wire, 51 Single core wire, 52 Metal tube, 61 Multi-core structure material, 62 Precursor raw material powder, 63 Metal sheath part, 64 Isotropic multi-core bus wire, 71 Isotropic multi-core bus wire, 72 Tape-shaped precursor wire 81 Rolling roll, 82 plate precursor, 83 plate chip, 101 dice, 121 former, 122 conductor layer, 123 insulation layer, 124 magnetic shield layer, 125 heat insulation layer, 126 outer tube, 127 oxide superconducting wire, 131 coil, 132 electrodes, 133 permanent current switch, 141 primary superconducting coil, 142 secondary superconducting coil, 143 primary power Pole, 144 secondary electrode, 145 core.

Claims (6)

Filling a metal tube with a precursor powder of (Bi, Pb) 2223 superconductor;
Plastically processing a metal tube filled with the precursor powder;
A method of manufacturing an oxide superconducting wire comprising a heat treatment step of heat treating the wire after the plastic working step,
A method for producing an oxide superconducting wire, comprising compressing and molding the precursor powder into a plate shape, and then filling the plate precursor powder into a metal tube.   The plate precursor powder is filled into the metal tube so that the ab plane direction of the superconducting crystal contained in the plate precursor is aligned with the longitudinal direction of the metal tube. Manufacturing method of oxide superconducting wire.   The method for producing an oxide superconducting wire according to claim 1 or 2, wherein the compression molding is performed by rolling.   The method for producing an oxide superconducting wire according to any one of claims 1 to 3, wherein the metal powder is filled after the compression-molded precursor powder is heat-treated.   The method for producing an oxide superconducting wire according to any one of claims 1 to 4, wherein the precursor powder of the (Bi, Pb) 2223 superconductor has a tetragonal Bi2212 phase as a main phase.   A superconducting device comprising, as a conductor, an oxide superconducting wire manufactured by the manufacturing method according to any one of claims 1 to 5.

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