JPS59201321A - Method of producing multicore 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 a superconducting wire, and particularly to a method for manufacturing a multi-core superconductor i19 that enables stable extrusion during hydrostatic extrusion.

[Technical Background of the Invention] Hitherto, as a method for efficiently manufacturing a superconducting wire having a multi-core structure, a method using (2) before hydrostatic extrusion has been known.

In this method, for example, Qu shown in FIG.
Alloy superconducting water such as Nb-Ti and Nb-7r in the stabilizing material 1! ! Composite line 3 with 2 pushed in, or the same figure (b
), metals 4.5 each containing either an element or an alloy that can form a superconductor compound such as Nb5sn or V 3 Ga by heat treatment are added to the IC11 stabilizing material 1'. Composite line 3' placed through 6
As shown in FIG. 2(0), a large number of the tubes were housed in a Cu tube 6 made of a stabilizing material, and as shown in FIG. 2(a),
After applying a vacuum to the inside thereof and capping both ends with a tip member 7 and a rear end member 8 forming a nose,
A C billet 9 is manufactured by electron beam welding the C1l tube 6, the tip member 7, and the rear end member 8, and then this billet is hydrostatically extruded and covered, thereby manufacturing a multicore superconducting wire.

The material of the tip member 7 of [Pyrene]・9 has a material in which the extrusion pressure of the tip member is lower than the extrusion pressure of the billet body <K
Alloys such as Cu-Cr and Cu-Be are selected so that

[Problems with Soda technology] However, in the above method, the average hardness of the billet 9, that is, the value obtained by distributing the hardness of each material in the cross section perpendicular to the axial direction of the billet 90 by the area ratio. The average value (approximate to the extrusion pressure in the portions of the billet where the cross-sectional area is the same) is calculated between the tip member 7 and the portion where the composite wire 3 is accommodated, as shown in FIG. 2(b). During hydrostatic extrusion of the billet, the extrusion pressure increases rapidly when the part where the composite wire is housed reaches the vicinity of the die, and the shock causes the composite wire 3 to break through the wall of the CII tube 6. The tip member 7 is ll1ff
There was a risk that it would come off.

Such a phenomenon is more likely to occur as the copper ratio (ratio of Cu stabilizing material to superconducting material) of the composite wire becomes smaller, and therefore it has been difficult to hydrostatically extrude a multicore superconducting wire with a small copper ratio.

``Object of the Invention 1 The present invention was made to solve the conventional drawbacks mentioned in 1, and is a method for stably hydrostatically extruding multicore superconducting wires by improving the structure of the extrusion billet. The purpose is to provide

3- [Summary of the Invention 1 Method for manufacturing a multi-core superconducting wire of the present invention] [(embedding a superconducting material or heat-treated metal in a plurality of metal 71-ricks) In a method of hydrostatically extruding a composite wire into an extruded pyrene 1 formed by housing a composite wire in a metal tube and sealing both ends thereof with a tip and a rear end member, after the extrusion billet of the tip member is It is characterized by a reinforcing material having higher hardness than the tip member embedded in the end side.

In the present invention, since a reinforcing material having a higher hardness than the tip member is pushed into the rear end side of the extruded billet of the tip member, the average hardness from the tip member to the part where the composite wire is accommodated during hydrostatic extrusion is It is possible to prevent a sudden increase in extrusion pressure by tying up the material in stages or continuously.

This reinforcing material can be embedded in multiple locations rather than in one location, and its shape can be reduced in cross-sectional area stepwise toward the rear end of the extruded billet, or tapered. It can also be formed to increase the area.

The material of the reinforcing material is Cu-Cr, similar to the tip member.

Alloys such as Cu-Ni and Cu-Be are used, but
It is necessary to change the composition ratio and heat treatment conditions so that it has higher hardness than the tip member.

In the present invention, the metal matrix and metal tube of the composite wire are pure Cu (OF
HC) and C11 alloys, such as Cu-Ni alloys, are used for special purposes.

Furthermore, the composite wire itself can have a multicore structure, for example, a plurality of Nb in the CIJ or CLI alloy matrix.
By using a structure in which the Ti wire or the CLI coated S gold wire is placed in the Nb tube, it is possible to easily increase the number of cores.

In the extruded billet used in the present invention, for example, a large number of composite wires (single wires or multi-wires) with a regular hexagonal cross section are housed in a tube made of a stabilizing material, and the tip and rear ends are used as the tip member and the rear end. After the parts are assembled, the tube and the leading and trailing parts can be manufactured by electron beam welding. Since the billet is held in a vacuum system during this welding, the inside of the billet can be evacuated at the same time, and the composite assembly 11 can be perfectly bonded during extrusion.

[Embodiments of the invention] An embodiment of the present invention will be described below.

Each (a) of FIG. 3 to FIG. 6 shows a longitudinal cross-sectional view of extrusion billet 1 to 1 according to the present invention, and each (b) of the same shows each amount (X) of the corresponding extrusion billet. It shows the average hardness (T1).

In FIGS. 3 to 6, the same parts as in FIG. 2 are indicated by the same symbol Y (.

In FIGS. 3 and 5, reinforcing materials 10 and 10' are embedded at one or more locations from the billet to the rear end of the tip member 7' of the extruded throat 9'. The cross-sectional area of the reinforcing material (in Figure 5 -C is the total cross-sectional area) is set to a value that is between the average hardness of the tip member 7' to the circle 11 and the average hardness of the billet body B. has been done.

In addition, in FIGS. 4 and 6, reinforcing material 11.11
' has a tapered shape that increases the cross-sectional area from the billet l to the rear end side, and in this case, the extrusion pressure increases even more smoothly, and the average hardness including this reinforcing material 11.11' The average value is set to be an intermediate value between the average hardness of the cylindrical portion A and the average hardness of the billet body portion B.

Although not shown in detail, it is also possible to eliminate the stepwise increase in extrusion pressure by making the tip end of the tapered reinforcing material conical, for example, and by selecting the material of the tapered reinforcing material.

A concrete C11 tube with an exception diameter of 100uφ and an inner diameter of 85φ has a copper ratio of 0.
301 Nb-Ti composite wires of No. 7 were accommodated, and the tip member was formed of a Cu-Cr alloy with a hardness of Hv=150. The structure of the billet in this case corresponds to Fig. 2(a),
The average hardness of the part where the composite wire is accommodated is Hv=180
Met.

On the other hand, the average hardness Hv=
Reinforcement material 7- made of Cu-13e alloy of 210 (height 401111, parallel planes 551 mφ and 70
A billet with the structure shown in Fig. 4(a) is made by inserting a circle ε1 of miφ into a base), and these extruded billets are
Using a die of 0 ■φ (as a result of hydrostatic extrusion processing, 6
In the billet of person f, the maximum pressure cuff of the tip member is 0
The extrusion pressure suddenly increased from 00 kg/cl to 9,000 kg/cl, which reached the billet main body where the composite wire was housed, causing the C1l tube to burst and the tip member to fly off with a roaring sound.

In the case of one-thrower Pilet I., 7000 kg/
Gradually back pressure from cl to extrusion pressure of 9000 kg/d
It was possible to extrude uniformly over the entire length of billet 1.

[Effects of the Invention] As explained above, according to the present invention, it is possible to prevent a sudden increase in extrusion pressure during hydrostatic extrusion processing, so that a superconducting wire having a multicore structure can be manufactured in a stable state.

[Brief explanation of drawings]

Figures 1 (a) and (b) are cross-sectional views of compound wires to explain the manufacturing process of conventional extrusion billets, and Figure 1 (C).
2(a) is a cross-sectional view showing a composite wire housed in a CIJ tube, FIG. 2(a) is a longitudinal sectional view of a conventional extruded billet, and FIG.
b) is an explanatory diagram showing the average hardness at each position, Figures 3 to 6 show examples of extruded billets used in the present invention, and each figure (a) is a longitudinal cross-sectional view of the extruded billet. , each figure (b) is an explanatory diagram showing the average hardness at each position of the extruded billet corresponding to figure (a). 3.3'...Composite line 6...COO 127'...Tip member 8......Rear end member 9.9' ...Billets 10.10', 11.11'... Reinforcement agent attorney Suyama Sa - (1 idiot) Figure 1 (C) The falsification at the end of the list in Figure 2 is Fig. 5 ◆-1 χ Fig. 4 φ-1 φ-1

Claims (6)

[Claims] (1) A plurality of composite wires consisting of a superconducting material or a metal that forms a superconducting material through heat treatment embedded in a metal matrix are housed in a metal tube, and both ends thereof are sealed using front and rear end members. In a method of isostatically extruding an extruded billet formed by Superconducting wire! ll
ll method. (2) The method for manufacturing a multicore superconducting wire according to claim 1, wherein the metal matrix is made of C11 or a C11 alloy. (3) A method for manufacturing a multicore superconducting wire according to claim 1, wherein a plurality of superconducting materials or metals forming superconducting materials by heat treatment are embedded in a metal matrix. (4) The method for manufacturing a multi-core superconducting wire according to claim 1, wherein the metal tube is made of C++ or C11 alloy. (5) The method for manufacturing a multi-core superconducting wire according to claim 1, wherein the reinforcing material is embedded in a plurality of locations. (6) A method for manufacturing a multi-core superconducting wire according to any one of claims 1 to 5, wherein the reinforcing material has a cross-sectional area increasing toward the rear end side of the extruded billet.