JPH01615A - Method for manufacturing oxide superconductor wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for manufacturing an oxide superconductor wire.

[Conventional technology]

Superconducting materials that have zero electrical resistance at extremely low temperatures include niobium (NbTi, NbSn, Nb3Ge, etc.).
b) When applied to system elements, electromagnets, rotating machines such as superconducting wire zero generators, transformers, etc., they were used while being cooled with liquid helium. For this reason, it is not easy to use superconducting wires, magnets, etc., and there is a problem in that their application and spread are limited. Another problem is that helium, which is a scarce resource and is expensive, must be used for cooling.

Recently, materials that become superconducting at higher temperatures than Nb-based superconductors have been discovered one after another. For example, the composition formula (La+-xs
In the superconducting material represented by rX)2cu04-y, the superconducting critical temperature shows SOK. Also (yxoay) 3 cu
2o7 becomes superconducting at a liquid nitrogen temperature of 77. However, since these series of oxide superconducting materials are made by sintering compound powder, it is difficult to make them into wire rods.

[Problems to be Solved by the Invention] An object of the present invention is to provide a method for manufacturing an oxide superconducting wire.

[Means for Solving the Problems] In order to achieve such an object, the present invention includes a process of depositing a mixture of salts of elements constituting an oxide superconductor on the surface of a conductor wire, and The method is characterized by comprising the steps of: heating the conductor wire to decompose and oxidize the salt into an oxide to form an oxide superconductor having a rough perovskite structure; and forming an insulating layer on the surface of the superconductor. do.

[Function J] According to the present invention, oxide superconductors are continuously formed on the surface of highly flexible conductor wires. It is possible to manufacture long and flexible superconducting wires using this method.

[Example] The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the method for producing an oxide superconductor wire according to the present invention.

First, a conductor wire 1 having an arbitrary cross-sectional shape is set in the conductor wire supply device 2. This conductor wire 1 holds an oxide superconductor on its surface to ensure the mechanical strength of the manufactured superconducting wire, and also prevents superconductor breakdown due to magnetic fields generated due to current flowing through the superconducting wire or unexpected circumstances. In order to ensure safety when
A wire made of a conductive material that is non-magnetic and has sufficient mechanical strength, such as i-alloy or non-magnetic stainless steel, is used. Conductor wire 1
The desirable cross-sectional shape will be described in detail later, but all wires including wires with a circular cross section and tape-shaped materials with a flat cross section will be referred to as conductor wires.

The conductor wire 1 fed out from the conductor wire supply device 2 is first introduced into a first cleaning device 3 containing a detergent such as Triclean, and is cleaned. The conductor wire 1 is then introduced into the second cleaning device 4, and the surface of the conductor wire 1, whose surface has been cleaned, is then introduced into the adhesion bath 5, where detergent adhering to the surface is washed away, for example, by a shower of distilled water. The deposition tank 5 contains a solution of octylate, specifically 2-ethylhexylate, of elements constituting the oxide superconductor, such as Cu, Ba, and Y. The mixing ratio of each salt is the desired atomic ratio for each constituent element, for example, Cu:Ba:Y = 1:o, 5
: Set it to 0.5. As a solvent for the octylate solution, for example, thinner, toluene, etc. are used. A solution of salts of each element constituting the oxide superconductor adheres to the surface of the conductor wire 1 that has passed through the adhesion bath 5. The conductor wire 1 with the salt solution adhered to its surface then enters a synthesis heat treatment furnace 6. The heat treatment furnace 6 is, for example, an electric furnace, and is
℃,! The conductor wire 1 is heated for about 5 minutes. As a result, octylate was decomposed and oxidized on the surface of the conductor wire 1 (Y
Ba) An oxide layer represented by Cu2O is formed. The deposition and heat treatment are repeated until the thickness of the oxide layer is the desired size. After the thickness of the oxide layer reaches a desired thickness, the temperature of the synthesis heat treatment furnace 6 is raised to, for example, 800° C. and heated for about 5 hours, thereby converting the oxide layer into an oxide superconductor layer having a perovskite structure. It can be done. In the elementary process of using octylate as an oxide, the temperature of the synthesis heat treatment furnace 6 is increased and the time is increased to achieve a perovskite structure, and the deposition of salt solution and the formation of a perovskite type oxide are repeated to achieve the desired thickness of superconductivity. It is of course also possible to obtain a body layer. Wire rod 70 with a superconductor layer formed on the surface
A 5i02 coating is formed on the surface by, for example, sputtering or vapor deposition by an insulating material deposition device 8, and if necessary, it is shaped to a predetermined size by a final dimension processing device 9, and then processed by a wire winding device. 10.

FIGS. 2 to 5 show the shapes of the superconducting wires manufactured in this manner.

2 and 3 show shapes suitable for direct current superconducting wires; FIG. 2 shows an example of a wire with a circular cross section, and FIG. 3 shows an example of a tape-shaped wire with a flat cross section. In both figures, 11 is a conductor wire, 12 is an oxide superconductor formed on the conductor wire 11, and 13 is a surface insulating layer.

1 Figure 4 shows the shape of an AC superconducting wire. A plurality of spiral grooves, JoA, are formed on the surface of the conductive material 21 having a circular cross section, and an oxide superconductor 22 is formed in the groove 21A. An insulating layer (not shown) is provided covering the conductor 21 and the superconductor 22 to complete the oxide superconducting wire. In this way, the oxide superconductor 22 is inserted into the groove 21 of the conductor 21.
If formed in the shape A, it is possible to prevent destruction of the superconductor 22 due to alternating stress acting on the superconductor 22 due to the magnetic field generated when a large alternating current is passed through the superconductor 22.

FIG. 5 shows another example of a superconducting wire manufactured according to the present invention. In this example, the conductor 31 is tape-shaped with a flat cross section. Groove 31A is groove IA in yg4 diagram
It is a groove in the same way as the groove. 32 is an oxide superconductor, 3
3 is an insulating film made of 5102 or the like. The cross-sectional shape and dimensions of the conductor for forming the oxide superconductor on its surface can be arbitrarily determined as necessary. The salt for forming the oxide superconductor is not limited to octylate, and the type and ratio of each constituent element can also be selected depending on the material of the intended oxide superconductor. Furthermore, since the oxide superconductor layer can pass a large current even if it is thin, the manufactured superconducting wire can maintain its flexibility.

[Effects of the Invention] As explained above, according to the present invention, a long and flexible superconducting wire can be manufactured using an oxide superconductor that has a high critical temperature but is brittle and difficult to make into a wire. It is possible to do so.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram explaining the present invention in detail, and FIGS. 2 to 5 are diagrams showing the shape of a superconducting wire manufactured according to the present invention. DESCRIPTION OF SYMBOLS 1... Conductor wire, 2... Conductor wire supply device, 3.4... Cleaning device, 5... Deposition device, 6... Synthetic heat treatment device, 7... Superconducting wire, 8... - Insulating material adhesion device, 9... Final dimension processing device, 10... Superconducting wire winding device, 11, 21.31... Conductor wire, 12, 22.32... Oxide superconductor, 21A , 3
1A... Groove, 13, 33... Surface insulating layer. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A step of depositing a mixture of salts of elements constituting an oxide superconductor on the surface of a conductor wire, and heating the conductor wire to which the salt is attached to decompose and oxidize the salt to form an oxide. A method for manufacturing an oxide superconductor wire, comprising the steps of: forming an oxide superconductor with a perovskite structure; and forming an insulating layer on the surface of the superconductor.