JPS60262310A - Method of producing nb3sn superconductive 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 [Technical Field of the Invention] The present invention relates to a method for manufacturing an Nb5Sn superconducting wire, and particularly to a method for manufacturing an Nb5Sn superconducting wire having an internally diffused multicore structure.

[Technical background of the invention and its problems]

Nb58n superconducting wire exhibiting good superconducting properties in a high magnetic field is generally manufactured by heat treating a ternary composite wire containing Nb18n and Ou. This is 100
This is because the direct reaction between Nb and 8n, which requires a high temperature of 0° C. or higher, is reduced to about 600° C. by using O as a diffusion path.

An internal diffusion method is known as a method for manufacturing such Nbl 8n superconducting wire.

Internal diffusion methods include a bronze method in which Nb is placed in an OuSn alloy, and a pipe structure method in which 8n is placed in a Nb pipe through O, but the former requires a lot of intermediate annealing to work harden the bronze. The latter has the disadvantage that it is difficult to manufacture ultra-fine wires, that is, to manufacture superconducting wires with a multifilament structure.

An application has been filed for a method for manufacturing Nb3Sn superconducting wire, which is characterized in that a mixture of powders, etc. is press-molded, then placed in a Cu pipe, and then processed to reduce its cross section to give it a final shape, and then heat-treated. (Japanese Patent Application No. 58-58973 and Japanese Patent Application No. 72496-1983).

However, in these methods, the Ou powder and the Ou vibe are contaminated with Sn, so a stabilizing material must be placed separately. It is also possible to arrange Qu-vibes as materials in order and heat-treat them after processing, but since Nb-vibes are used,
When a high degree of surface reduction processing is performed, the Nb vibrator tends to break in the circumferential direction or in the axial direction, and the stabilizing material is easily contaminated with Sn. The present invention was made in order to solve the above-mentioned difficulties, and the object is to provide a method for manufacturing an Nbs 8n superconducting wire that can be made ultra-fine by adding Zr to the Nb tube.

[Summary of the invention]

The method for manufacturing the Nb, an superconducting wire of the present invention includes
A Sn or Sn-based alloy rod coated with Cu or Ou-based alloy was housed inside □1' of the N6-based alloy tube to which at% of Zr was added, and a stabilizing O was placed outside the Nb-based alloy tube. After applying reduction processing to the composite, N
b. It is characterized in that it is subjected to heat treatment to generate Sn.

In the present invention, the amount of Zr added to the Nl)-based alloy tube must be in the range of 0.1 to 2 at%, especially 9
．． A range of 5 to 1.05 at% is suitable.

Outside the above range, the wire breakage rate of the Nb-based alloy tube increases significantly when the multi-core structure is made to be ultra-thin.

Further, the heat treatment in the present invention is performed at a temperature range of 600 to 800°C, and the heat treatment time is appropriately selected in the range of several tens of hours to over 100 hours depending on the structure of the wire.

[Embodiments of the invention]

Examples of the present invention will be described below.

Example 1 N b -1a t%Z with outer diameter 8Mφ and inner diameter 5.6mmφ
C, u coating 8nM with outer diameter 5.4jl@φ inside r alloy tube
(xs, s3t%Sn), outer diameter IQ, 3
After arranging the smφ Qu tube, this was subjected to cross-section reduction processing to produce a single wire with a parallel plane opening movement of 1112.52fi.

Seven of these single wires have an outer diameter of 10.3φ and an inner diameter of 8.1
700 to 1 box with an outer diameter of 0.287 mm and obtained by applying cross-section reduction processing to it after placing it inside the gate φ.
``CX 96 hours of heat treatment was applied to produce a super'r# conductor.The critical current value of this super 1!conductor was 2 at 10'L'.
It was 1A.

Actual Blood Example 2 N l) The outer diameter of the O u tube placed on the outer periphery of the alloy tube is 9.7
A single wire with a parallel surface opening of 11i 2.27 M was manufactured by subjecting a composite body constructed in the same manner as in Example 1 except that the diameter was changed to φ to reduce the cross section. After housing 264 of these single wires in a Cu tube with an outer diameter of 49 mm and an inner diameter of 43.5 m,
When this was subjected to cross-section reduction processing to reach the wire drawing processing limit for Nb tubes, no breakage of the Nb tube occurred up to an outer diameter of 30 μmφ, and when processed to a diameter smaller than this, the wire breakage rate of the Nb tube increased significantly and wire drawing It became impossible to process.

Comparative Example 1 When the same processing as in Example 1 was performed using a Nb tube instead of the N1)-Zr alloy tube in Example 1, the expansion/contraction processing limit was 0.43 Mφ.

〔Effect of the invention〕

As described above, according to the present invention, after heat treatment, Nb3
By adding a small amount of Zr to the N + ) tube that generates Sn, it is possible to easily manufacture a multicore Nb, 8n superconducting wire.

Continuing from page 1 ■Int, CI,' Identification code Internal reference number 0 Inventor Nobuo Aoki Inside Oda Sakae, Kawasaki-ku, Kawasaki City ' 2-1-1 Showa Electric Wire & Cable Co., Ltd.

Claims (1)

[Claims] An 8N or Sn alloy rod coated with Ou or Qu alloy is housed inside a Nb-based 4 alloy tube to which 0.1 to 2 at % of Zr is added, and a stabilized rod is placed outside the Nb-based alloy tube. A method for producing a Nb38n superconducting wire, which comprises subjecting a composite in which O is arranged to a reduction processing and then subjecting it to heat treatment to generate Nb18n.