JPS62262312A - Nb-ti alloy system superconductor wire material - 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 1. Field of Industrial Application The present invention is directed to the use of Nb-Ti alloy superconductors used in superconducting magnets, particularly cu/Cu-Ni/Nb-
The present invention relates to a composite multicore superconducting wire having a three-layer structure of Ti.

[Prior art and its problems 1. Superconducting magnets used in superconducting magnets used in pulsed C--mode or commercial frequency (501-1z or 60Hz) mode! The + line month is ■Cu to reduce AC loss.
/GO-Ni /Nb-Ti three-layer structure, ■Nb-1'i filament is progressing in the direction of ultra-fine filament of 10 μm or less.

The reason for using Cu-Nt is to reduce coupling loss and eddy current loss by providing a high electrical resistance layer.
The purpose of making the filament extremely thin is to reduce pinning n. In addition, Cu is a so-called stabilizing material and Nb-'r
Pf is provided for the purpose of bypassing the side flow when the superconducting state of the i section is broken. Therefore, the smaller the resistivity at cryogenic temperatures, the better it is as a stabilizing material.
Generally, oxygen-free copper with a purity of 1 is used.

In such a wire structure, the heat treatment during the manufacturing process increases the ratio of the reaction layer between different metals to the rest, and the wire drawability is C
A problem arises in that the stabilization capacity of the u part is reduced.

[Object of the invention] The object of the present invention is to solve the above-mentioned Cu/Cu-N i
The object of the present invention is to provide a superconducting wire that eliminates the drawbacks of the /Nb-Ti three-layer structure superconducting wire, has excellent workability, and has less contamination of stabilized copper, that is, has excellent thermal and electrical stability.

1 Komei IR requirements] The gist of the present invention is that Cu/Cu-Nt, Cu/
CU at the Nb-T1 and C+rN i /N b-T i interfaces.

Ni, a metal that does not easily react with the fi element, such as Nb or l
By arranging -a, one of the three types of reactions listed in L was achieved, and workability and stability were ensured.

In this case, the Nb or Ta layer has no function other than suppressing the diffusion reaction, and the fact that this layer is thick means that the Nb or Ta layer has no function other than suppressing the diffusion reaction.
The ratio of the layer to the entire wire becomes large, and the actual stability and F3-IC characteristics are lowered to 1"L5.

Therefore, its thickness should be as thin as possible, for example 1μrTl
The following is desirable.

Note that Nb-'i does not support the axe even if it is a ternary alloy containing a third element such as /r, '[a, @r, etc.

[Embodiment 1] Hereinafter, an embodiment will be described with reference to the drawings. Fig. 1 shows the manufacturing process of a composite multi-core super-fri conductor.

In the strand i shown in (a), a layer 1 of Qu is formed on the outside of the Nb-Ti alloy 3 with a layer 2 of Nb interposed therebetween.

In the example, a Nb tube with an outer diameter of 16 M and a wall thickness of 0.3 m was placed on the outside of a Nb-46,5% Ti rod with an outer diameter of 15 sI,
Furthermore, a wire (single Fil) was obtained by drawing an oxygen-free steel tube having an outer diameter of 2111 IIR and a wall thickness of 2.2 rm to an outer diameter of 1.2 m by drawing.

In the next step, this wire is made into a sub-multi wire in which many of the wires are covered with a layer 2 of Nb and a layer 3 of Cu--Ni alloy, as shown in FIG. 3(b).

In the example, Cu-1 has an outer diameter of 22.8st and a wall thickness of 1.4m.
A Nb tube with an outer diameter of 19.4!191 and a wall thickness of 0.2 rtm is placed inside the 0% Ni alloy tube, and a single wire of 361 wood is inserted into the Nb tube, and the outer diameter is adjusted by drawing. The wire was drawn to 1.2 m.

The wire shown in FIG. 1(C) is a dummy wire in which a Cu--Ni alloy P:A4 is formed on the outside of a Cu layer 2 with an Nb layer 2 interposed therebetween.

In the example, a Nb tube with an outer diameter of 19.4 mm and a wall thickness of 0.2 m was placed outside an oxygen-free copper rod with an outer diameter of 18#Ill+, and a Cu- tube with an outer diameter of 23#L and a wall thickness of 1.5aa+ was placed outside. A 10% Ni alloy tube was placed and the assembly was pulled out (hanging 1.2
The wire was drawn to m.

In the next step, a layer 4 of CU-Ni alloy is formed on the outside of the plurality of sub-multi lines arranged around the plurality of dummy lines.

In the example, Ctl-1 has an outer diameter of 21.8M and a wall thickness of 1.4mm.
A 0% N1 alloy tube with a dummy wire of 109 mm in the center and a rib mulch wire of 252 mm on the outer periphery is added to the 0% N1 alloy tube. Perform twisting near the wire diameter,
The wire was drawn to a final outer diameter of 0.65 m, and the wire drawability was extremely good, with no defects such as I2 observed. In addition, the final outer diameter is 0
．． Nb-T at 65m5! 1 filament, outer diameter approximately 1
It was μm.

When I made a prototype similar to Habo without NIl'i'3,
Heat treatment at 350-400℃ for 50-100 hours III! (
There were many wire breaks, and there was a clear difference in stretchability.
child. Table 1 shows various properties of the wire rods of the examples, and it is clear that the wire rods of the present invention in which the Nb layer is provided are superior.

Also, the above two types of I! When 1144 was heat treated at 250℃ for 2 hours, the residual resistance ratio of the steel part of the conventional Xn material was 35.
In contrast, the present invention I! il shrine is 150
and the electrical resistance became extremely small.

Furthermore, even when Ta tubes were used instead of Nb tubes, both wire drawability and performance were almost the same as those using Nb tubes. However, considering economic efficiency, Nb tubes are preferable1).

FIG. 2 shows another example of a single line, in which parts of the same material are designated by the same reference numerals as in FIG.

In addition, for the high surface configuration of the final wire, use a dummy wire in the center! I
11! Although we have shown the case where the dummy wire is installed, even if it is an all-rib multi-type that does not include the dummy wire, it is still possible.

Further, although a tube material was used to form the NbIPl, this may be substituted by winding a cheap plate material.

Table 1 [Effects of the Invention] The present invention uses Nb or Ta, which does not easily react with Cu, Ti, and Ni.
is installed at each interface, the reaction during heat treatment is suppressed, the processability is excellent, and the relative lowness of 00 parts is small. A superconducting wire can be provided.

[Brief explanation of drawings]

FIG. 1 shows the manufacturing process of superconducting wire according to the present invention.
FIG. 2 is a diagram showing another example of a single line as a modified array. 1: Cu, 22Nb, 3: Nb-Ti, 4: Cu-Ni.

Claims (2)

[Claims] (1) In a composite multicore superconducting wire with a Cu/Cu-Ni/Nb-Ti three-layer structure, Cu/Cu-Ni, Cu
Nb-Ti characterized in that Nb or Ta is arranged at each interface of /Nb-Ti and Cu-Ni/Nb-Ti
Alloy superconducting wire. (2) The superconducting wire according to item 1 above, wherein the thickness of Nb or Ta is 1 μm or less.