JP2011014404A - Device and method of manufacturing superconducting wire material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing device and method, which can manufacture a high-quality superconducting wire material by securely joining a stabilized layer wire material and oxide superconducting layer wire material irrespective of their types, and can prevent degradation of productivity and workability.SOLUTION: The device of manufacturing a tape-like superconducting wire material 7 by joining the stabilized layer wire material 1 with the oxide superconducting layer wire material 2 through solder, includes a preheating means 3 for heating a composite material 6 formed by overlapping the stabilized layer wire material 1 and the oxide superconducting layer wire material 2 through a solder layer at a melting temperature of the solder or higher, and a pressurizing means 4 for pressurizing the composite material 6 through the preheating means 3, and joining the stabilized layer wire material 1 with the oxide superconducting layer wire material 2 to obtain the superconducting wire material 7. A position of the pressurizing means 4 can be adjusted with respect to a moving direction of the composite material 6.

Description

  The present invention relates to an apparatus and method for manufacturing a superconducting wire that can be applied to energy storage (SMES), a transformer, a motor, a generator, and the like, and more particularly, an oxide superconductor such as an yttrium oxide superconductor. The present invention relates to an apparatus and a method for manufacturing a tape-shaped superconducting wire by joining the used oxide superconducting layer wire and a stabilizing layer wire through solder.

A superconducting wire using an oxide superconductor such as an yttrium oxide superconductor is manufactured by coating a thin film of an oxide superconductor on a tape-like metal substrate.
In superconductors, the superconducting state is maintained within the range of critical conditions defined by the three parameters of critical temperature, critical current, and critical magnetic field. However, depending on the usage conditions of the superconductor, May become a normal conducting state and generate heat, which may cause a quench phenomenon in which the entire superconductor transitions to the normal conducting state.
Therefore, to prevent the quenching phenomenon, a superconducting metal stabilization layer is provided in combination with the superconductor to stabilize the current when a part of the superconductor becomes normal conducting state during energization. A structure that can be passed through the layer is employed to stabilize the superconducting state.

As an apparatus for forming the stabilization layer, there is an apparatus for forming a stabilization layer made of Ag by a film forming method such as sputtering or vapor deposition (see, for example, Patent Document 1). However, depending on the characteristics of the superconductor, the stabilization is thick. In recent years, it has been studied to join a tape-shaped stabilizing layer wire to a superconducting layer wire.
As an apparatus for joining the stabilization layer wire to the superconducting layer wire, the superconducting layer wire and the stabilization layer wire are immersed in molten solder and joined by solder (see Patent Document 2), the superconducting layer wire and the stabilization layer. There is an apparatus for joining a superconducting layer wire and a stabilizing layer wire by overlapping the wire with solder via a heating / pressurizing roll (see Patent Document 3).

JP 2006-236652 A JP 2008-60074 A JP 2009-48987 A

However, in the technique of forming a composite wire superposed via a solder layer formed by immersing in molten solder, such as the apparatus described in Patent Document 2, the superconducting layer wire and the stabilization layer wire are joined. In some cases, it was insufficient. Further, since the entire combined wire is covered with solder, the width and thickness of the wire may be uneven.
In addition, in the apparatus described in Patent Document 3, the superconducting layer wire and the stabilizing layer wire are brought into close contact with each other by passing the wire through a heating / pressurizing roll, and the solder is solidified, but depending on the thermal characteristics of the wire. The solder solidification timing becomes inadequate, and there is a possibility that the bonding between the superconducting layer wire and the stabilizing layer wire becomes insufficient.
This problem can be solved by limiting the wire feed speed or adjusting the timing of solder solidification by changing the condition settings such as heating and pressurization. There were problems such as taking time and effort.

  The present invention has been made in view of the above circumstances, and regardless of the types of the stabilizing layer wire and the oxide superconducting layer wire, it is possible to reliably bond them to produce a high-quality superconducting wire. In addition, an object is to provide a manufacturing apparatus and method that do not cause a decrease in productivity and workability.

The invention according to claim 1 of the present invention is an apparatus for producing a tape-shaped superconducting wire by joining a stabilizing layer wire and an oxide superconducting layer wire via solder, wherein the stabilizing layer wire is A first delivery means for delivering, a second delivery means for delivering the oxide superconducting layer wire, and a composite material obtained by superimposing the stabilizing layer wire and the oxide superconducting layer wire via a solder layer is melted in the solder. Preheating means for heating to a temperature or higher, and pressurizing means for pressurizing the composite material that has passed through the preheating means to join the stabilizing layer wire and the oxide superconducting layer wire to obtain the superconducting wire. The superconducting wire manufacturing apparatus is provided with at least the pressurizing means, the position of which can be adjusted with respect to the moving direction of the composite material.
The invention according to claim 2 of the present invention is the superconducting wire manufacturing apparatus according to claim 1, wherein the pressurizing means has a surface temperature lower than the solder melting temperature.
The invention according to claim 3 of the present invention is the superconducting wire manufacturing apparatus according to claim 1 or 2, wherein the pressurizing means has at least a surface made of a soft material.
According to a fourth aspect of the present invention, in any one of the first to third aspects, the direction changing means that shifts the moving direction of the superconducting wire in the thickness direction downstream of the pressurizing means. It is the manufacturing apparatus of the superconducting wire provided.

  A method for producing a superconducting wire according to claim 5 of the present invention is a method for producing a superconducting wire using the superconducting wire producing apparatus according to any one of claims 1 to 4, wherein The composite material is introduced into the preheating means and heated to a temperature equal to or higher than the melting temperature of the solder, and the composite material that has passed through the preheating means is pressurized by the pressurizing means, and the stabilizing layer wire and the oxide In joining the superconducting layer wire to make the superconducting wire, the position of the pressurizing means is introduced into the pressurizing means before the solder is solidified, and the solder is solidified under pressure. It is the manufacturing method of the superconducting wire made into the position which can be made to be.

According to the present invention, since the pressurizing means can adjust its position with respect to the moving direction of the composite material, by optimizing the position of the pressurizing means according to the thermal characteristics of the wire, Wires can be joined under suitable conditions.
For example, the composite material can be introduced into the pressurizing means before the solder is solidified, and the wire can be joined under the condition that the solder can be solidified under pressure.
Therefore, a superconducting wire in which the stabilization layer wire and the oxide superconducting layer wire are reliably bonded can be obtained regardless of the type of the wire.
Further, since the conditions for joining the wire can be optimized by adjusting the position of the pressurizing means, it is not necessary to limit the feed rate of the wire for the purpose of adjusting the timing of solder solidification, and the productivity is not lowered.
Furthermore, since it is not necessary to change the temperature of the preheating means, the pressure of the pressurizing means, etc., the setting of the apparatus can be changed in a short time with an easy operation, and the workability is good.

It is a block diagram of one Embodiment of the manufacturing apparatus of the superconducting wire of this invention. It is a figure which shows the principal part of the manufacturing apparatus shown in FIG. It is a graph which shows a test result.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of an embodiment of a superconducting wire manufacturing apparatus according to the present invention. FIG. 2 is a diagram showing a main part of the manufacturing apparatus shown in FIG.
As shown in FIG. 1, this manufacturing apparatus 10 is an apparatus that obtains a tape-shaped superconducting wire 7 by combining a stabilization layer wire 1 and an oxide superconducting layer wire 2 by joining them together with solder. is there.
The production apparatus 10 includes a first delivery means 11 for delivering the stabilizing layer wire 1, a second delivery means 12 for delivering the oxide superconducting layer wire 2, and a preheating furnace 3 (heating furnace) for heating the composite material 6 ( Preheating means), pressurizing roll 4 (pressurizing means) that pressurizes the composite material 6 to form a superconducting wire 7, and a direction changing roll 5 (direction changing means) that changes the moving direction of the superconducting wire 7. I have.

The stabilization layer wire 1 can be a tape-shaped substrate made of a metal such as copper, Cu—Ni alloy, Ni—Cr alloy, nickel, stainless steel or the like. The thickness is preferably 50 μm to 200 μm.
A solder layer 1a (for example, melting point 230 ° C.) is preferably formed on one surface of the stabilization layer wire 1 to a thickness of about 2 μm to 10 μm by plating or the like.
As the solder constituting the solder layer 1a, Sn-based solder (Sn—Cu based, Sn—Ag based, Sn—Ag—Cu based, etc.) is suitable.
The first delivery means 11 is a roller that can feed out the stabilizing layer wire 1, for example.

The oxide superconducting layer wire 2 preferably has a structure in which a thin film of an oxide superconductor is formed on a tape-like base material made of metal and a stabilization layer made of silver is provided thereon.
The constituent material of the base material is preferably a nickel alloy (such as Hastelloy), stainless steel, or copper alloy.
As an oxide _{superconductor, Y 1 Ba 2 Cu 3 O} 7-x, Y 2 Ba 4 Cu 8 O x, Y 3 Ba 3 Cu 6 O x, (Bi, Pb) 2 Ca 2 Sr 2 Cu 3 O x _{, (Bi, Pb) 2 Ca} 2 Sr 3 Cu 4 O x, Tl 2 Ba 2 Ca 2 Cu 3 O x, Tl 1 Ba 2 Ca 2 Cu 3 O x, etc. _{Tl 1 Ba 2 Ca 3 Cu 4} O x A representative oxide superconductor having a high critical temperature is preferable.
The thin film of the oxide superconductor can be formed by a pulse laser deposition method (PLD method) or the like.

An intermediate layer may be provided between the base material and the oxide superconductor thin film.
The intermediate layer controls the crystal orientation of the oxide superconductor thin film. Preferred material for the intermediate _{layer, Gd 2 Zr 2 O 7,} MgO, ZrO 2 -Y 2 O 3 (YSZ), SrTiO 3, CeO 2, Y 2 O 3, Al 2 O 3, Gd 2 O 3, Zr Examples thereof include metal oxides such as ₂ O ₃ , Ho ₂ O ₃ and Nd ₂ O ₃ . The intermediate layer may be a single layer or a plurality of layers. For example, a first intermediate layer made of Gd ₂ Zr ₂ O ₇ and a second intermediate layer (cap layer) made of CeO ₂ can be formed.
As a method for forming the intermediate layer, an ion beam assisted vapor deposition method (IBAD method), a pulse laser vapor deposition method (PLD method), or the like can be employed.
The 2nd sending means 12 is a roller which can pay out oxide superconducting layer wire 2, for example.

The preheating furnace 3 is configured so that the composite material 6 can be heated to a temperature higher than the melting temperature (melting point) of the solder. 1 and 2, reference numeral 3 a is an inlet of the preheating furnace 3, and reference numeral 3 b is an outlet of the preheating furnace 3.
The preheating furnace 3 is preferably one that can raise the composite material 6 to 30 ° C. or more higher than the melting temperature of the solder.

As shown in FIG. 2, a pair of pressure rolls 4 and 4 is provided, and the composite material 6 can be pressed in the thickness direction between them. The pressure applied to the composite material 6 by the pressure rolls 4 and 4 can be 100 MPa or less.
The positions of the pressure rolls 4 and 4 can be adjusted with respect to the moving direction of the composite material 6 (hereinafter referred to as a moving direction position). In the illustrated example, the pressure rolls 4 and 4 can move left and right within a predetermined range, and can be installed at any position within this range.

Although the positioning structure of the pressure rolls 4 and 4 is not particularly limited, for example, as shown in FIG. 2, a structure including a shaft support frame 9 that rotatably supports the shaft portion 4a of the pressure rolls 4 and 4 is provided. Is possible.
The shaft support frame 9 extends in the moving direction of the composite material 6 (left and right direction in FIG. 2), and can support the shaft portion 4a at an arbitrary position in this direction.

The pressure rolls 4 and 4 are preferably ones whose surface temperature can be set lower than the melting temperature of the solder. Thereby, the composite material 6 can be cooled to a temperature lower than the melting temperature of the solder by contact.
The pressure roll 4 may be made of a hard material such as a metal, but at least the surface is preferably made of a soft material such as a resin such as silicone rubber. The use of the soft material makes it difficult for the wires 1 and 2 to be damaged.

The pressure rolls 4 and 4 can be installed on the downstream side of the preheating furnace 3 (downstream side in the moving direction).
As shown in FIG. 2, the distance L1 from the outlet 3b of the preheating furnace 3 to the position where the pressure rolls 4 and 4 press the composite material 6 (pressure position 8) is the solder constituting the solder layer 1a. Can be set so as to decrease to a temperature lower than the melting temperature at or near the pressurizing position 8.

The direction changing roll 5 is provided on the downstream side of the pressure rolls 4 and 4 and shifts the moving direction of the superconducting wire 7 in the thickness direction.
In the example shown in FIG. 1, the direction of movement of the superconducting wire 7 is shifted downward by the direction changing roll 5, and the superconducting wire 7 moves in the horizontal direction between the pressure rolls 4, 4 and the direction changing roll 5. Unlike the material to be composited 6, it moves obliquely downward.
Thus, after passing through the pressure position 8, the superconducting wire 7 is not immediately separated from the pressure roll 4, but in a predetermined length region, the pressure roll 4 (in the illustrated example, the lower of the two pressure rolls 4) Therefore, even when the solidification of the solder is delayed, the wires 1 and 2 can be reliably bonded.
The direction changing roll 5 also has a function of cooling the superconducting wire 7.
In addition, the manufacturing apparatus of this invention can also be comprised without a direction change roll.

Next, an example of a method for manufacturing the superconducting wire 7 using the manufacturing apparatus 10 will be described.
The positions of the pressure rolls 4 and 4 are set in advance so that the temperature of the solder constituting the solder layer 1a is lowered to a temperature lower than the melting temperature at or near the pressure position 8 according to the characteristics of the wires 1 and 2. Is set.

  With the surface of the solder layer 1a of the stabilizing layer wire 1 and the surface of the silver stabilizing layer of the oxide superconducting layer wire 2 facing each other, these wires 1 and 2 are connected to the preheating furnace 3 from the inlet 3a. It was introduced into the inside and heated to a temperature higher than the solder melting temperature (for example, 250 ° C. or higher).

The composite material 6 is led out from the outlet 3b of the preheating furnace 3 and introduced between the pair of pressure rolls 4 and 4 (pressure position 8) before the solder solidifies, and is pressurized and from the solder melting temperature. It can be cooled to a low temperature (for example, 160 to 220 ° C. on the surface of the pressure roll 4).
Thereby, since the solder can be solidified under pressure, it is possible to efficiently and continuously produce the superconducting wire 7 in which the stabilization layer wire 1 and the oxide superconducting layer wire 2 are reliably bonded.

The thermal characteristics of the stabilizing layer wire 1 and the oxide superconducting layer wire 2, such as heat capacity and thermal conductivity, vary depending on the thickness and material. In particular, the thickness of the base material of the stabilizing layer wire 1 has a great influence on the thermal characteristics.
For this reason, depending on the thermal characteristics of the wires 1 and 2, the solidification of the solder may be accelerated or delayed, but in that case, it is stabilized by adjusting the moving direction position of the pressure rolls 4 and 4. Insufficient bonding between the layer wire 1 and the oxide superconducting layer wire 2 can be prevented.

For example, the wire rods 1 and 2 having a small heat capacity have a rapid temperature drop after leaving the preheating furnace 3, but in this case, the pressure rolls 4 and 4 are positioned relatively close to the preheating furnace 3 (reference numeral 4A in FIG. 2). Position).
Thus, the composite material 6 can be introduced into the pressure rolls 4 and 4 before the solder is solidified, and the solder can be solidified under pressure.
On the other hand, the wires 1 and 2 having a large heat capacity have a slow temperature drop after leaving the preheating furnace 3. 4B).
As a result, the composite material 6 can be introduced into the pressure rolls 4 and 4 after the solder temperature has dropped to a temperature close to the freezing point, and the solder can be solidified under pressure.

Thus, in the manufacturing apparatus 10, since the position of the pressure rolls 4 and 4 can be adjusted, by optimizing the position of the pressure rolls 4 and 4 according to the thermal characteristics of the wires 1 and 2, The wires 1 and 2 can be joined under suitable conditions.
For this reason, it is not necessary to limit the feed rate of the wires 1 and 2 for the purpose of adjusting the timing of the solder solidification, and the productivity is not lowered.
Moreover, since the conditions at the time of joining the wire rods 1 and 2 can be optimized by adjusting the positions of the pressure rolls 4 and 4, there is no need to change the temperature of the preheating furnace 3 or the pressure of the pressure rolls 4 and 4. Therefore, the setting of the apparatus can be changed in a short time with an easy operation, and the workability is good.
As described above, the manufacturing apparatus 10 can manufacture the high-quality superconducting wire 7 by reliably joining the wires 1 and 2 regardless of the types of the wires 1 and 2, and can improve productivity and workability. There is no reduction.

(Examples 1-3)
An intermediate layer made of Gd ₂ Zr ₂ O _{7 having a} thickness of 1 μm is formed on a substrate made of Hastelloy C276 having a thickness of 0.1 mm by ion beam assisted vapor deposition (IBAD method), and pulse laser deposition is performed thereon. A cap layer made of CeO _{2 having a} thickness of 0.5 μm is formed by the PLD method, and a thickness made of yttrium-based oxide superconductor (Y ₁ Ba ₂ Cu ₃ O _7-x ) is formed on the cap layer by the PLD method. A 2 μm oxide superconducting thin film was formed, and a 7 μm thick silver stabilizing layer made of silver was formed thereon to obtain an oxide superconducting layer wire 2. The oxide superconducting layer wire 2 had a width of 5 mm and a length of 1 m.

An Sn-based solder layer 1a having a thickness of 2 μm was formed on one surface of a tape-shaped substrate made of copper having a thickness of 0.1 mm by plating.
The width of the stabilizing layer wire 1 was 5 mm and the length was 1 m.

The superconducting wire 7 was manufactured as follows using the manufacturing apparatus 10 shown in FIG. 1 and FIG.
The surface of the solder layer 1a of the stabilizing layer wire 1 and the surface of the silver stabilizing layer of the oxide superconducting layer wire 2 were placed face to face and introduced into the preheating furnace 3 from the inlet 3a.
The temperature in the preheating furnace 3 was set to the melting temperature of solder plus 30 ° C.
The composite material 6 was led out from the outlet 3b of the preheating furnace 3, pressurized by the pressure rolls 4 and 4, and cooled to a temperature lower than the solder melting temperature. The surface temperature of the pressure rolls 4 and 4 was set to a solder melting temperature minus 40 ° C.
Thus, a superconducting wire 7 in which the stabilization layer wire 1 and the oxide superconducting layer wire 2 were joined was obtained.
The feeding speeds of the wires 1 and 2 were set to 25 m / h (Example 1), 50 m / h (Example 2), or 100 m / h (Example 3).

  About the superconducting wire 7 obtained in Examples 1 to 3, the width (bonding width) of the portion where the wires 1 and 2 were joined to each other was measured, and the ratio to the total width was calculated. The results are shown in Table 1.

  From Table 1, it can be seen that the bonding width varies depending on the feed rates of the wires 1 and 2.

(Examples 4 to 6)
Thickness by plating on one surface of a tape-shaped substrate made of copper having a thickness of 0.1 mm (Example 4), a thickness of 0.3 mm (Example 5), or a thickness of 0.5 mm (Example 6) A stabilization layer wire 1 in which a 2 μm Sn-based solder layer 1a was formed was prepared.
The oxide superconducting layer wire 2 was the same as in Example 1. The feeding speed of the wire materials 1 and 2 was 100 m / h.
Other test conditions were the same as in Example 1, and a superconducting wire 7 was produced.
Measure the bonding width of the wires 1 and 2 when the distance L1 (see FIG. 2) from the outlet 3b of the preheating furnace 3 to the pressure position 4 of the pressure rolls 4 and 4 is changed in the range of 0 to 15 cm, The ratio to the total width was calculated. The results are shown in FIG.

  As shown in FIG. 3, when the stabilizing layer wire 1 using a relatively thick substrate is used, the distance L1 is too short or too long. It can be seen that the junction width is maximized by setting to.

  DESCRIPTION OF SYMBOLS 1 ... Stabilization layer wire, 1a ... Solder layer, 2 ... Oxide superconducting layer wire, 3 ... Preheating furnace (preheating means), 4 ... Pressure roll (pressure means), DESCRIPTION OF SYMBOLS 5 ... Direction change roll (direction change means), 6 ... Composite material, 7 ... Superconducting wire, 10 ... Manufacturing apparatus, 11 ... 1st sending means, 12 ... 1st 2 sending means.

Claims (5)

An apparatus for producing a tape-like superconducting wire by joining a stabilizing layer wire and an oxide superconducting layer wire via solder,
First delivery means for delivering the stabilizing layer wire;
Second delivery means for delivering the oxide superconducting layer wire;
Preheating means for heating the composite material obtained by superimposing the stabilization layer wire and the oxide superconducting layer wire via a solder layer to a temperature equal to or higher than the melting temperature of the solder;
Pressurizing the composite material that has undergone the preheating means to join the stabilization layer wire and the oxide superconducting layer wire to obtain the superconducting wire,
The apparatus for producing a superconducting wire, characterized in that the position of the pressing means can be adjusted with respect to the moving direction of the composite material.   2. The superconducting wire manufacturing apparatus according to claim 1, wherein the pressurizing means has a surface temperature lower than the solder melting temperature.   The superconducting wire manufacturing apparatus according to claim 1 or 2, wherein at least the surface of the pressurizing means is made of a soft material.   The direction changing means for shifting the moving direction of the superconducting wire in the thickness direction is provided on the downstream side of the pressurizing means. Superconducting wire manufacturing equipment. A method for producing a superconducting wire using the superconducting wire production apparatus according to any one of claims 1 to 4,
The composite material is introduced into the preheating means and heated to a temperature higher than the melting temperature of the solder,
In forming the superconducting wire by joining the material to be composited through the preheating means, pressurizing by the pressurizing means, and joining the stabilizing layer wire and the oxide superconducting layer wire.
The position of the pressurizing means is a position where the composite material is introduced into the pressurizing means before the solder is solidified, and the solder can be solidified under pressure. Production method.

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