JP2000126848A - Device and method for manufacturing quenched alloy foil band - Google Patents

Abstract

(57) [Problem] To reliably and quickly produce a ribbon-shaped or flake-shaped hydrogen storage alloy having a thin thickness of a directionally solidified alloy foil strip, to simplify the production equipment and reduce the equipment cost. The present invention provides a quenched alloy foil strip manufacturing facility and a method thereof. A tundish (32) holding molten metal (34) inside and continuously dropping from a lower nozzle (33), a rotatable first cooling roll (35) provided at a molten metal drop position below the nozzle, and a first cooling roll (35). A second cooling roll 36 rotatably arranged opposite to the cooling roll, an endless belt 37 that is wrapped between the cooling rolls, tuned and rotated, and the quenched alloy powder 34 ′ is placed and conveyed thereto; And a tension roll 38 for applying tension to the endless belt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quenched alloy foil strip manufacturing apparatus and method for quenching molten metal to produce a ribbon or flake shaped alloy foil strip of a directionally solidified alloy.

[0002]

2. Description of the Related Art A single roll method and a twin roll method are known as a primary raw material production method of a metal powder, and a rotating disk method is known as a direct production method of a powder. As a single roll method,
For example, “Method for manufacturing permanent magnet material” (Japanese Patent Laid-Open No. 4-55)
No. 042) is disclosed. In this method, as shown in the schematic diagram of FIG. 2, a molten alloy 1 is injected from a nozzle 2 and collides with a peripheral surface of a single cooling roll 5 composed of a rotating base material 3 and a surface layer 4. Next, an inert gas is blown from a predetermined angle to the upper surface of the alloy 6 existing near the peripheral surface of the cooling roll 5 and cooled by the cooling roll 5, so that the lower surface of the alloy 6 is Extend contact time. As a result, the cooling effect can be improved, and the ribbon-shaped permanent magnet material 7 can be manufactured.

[0003] As a rotating disk method, for example,
"Method for producing amorphous alloy" (Japanese Patent Laid-Open No. 58-199)
647) and the like. In this method, as shown in the schematic diagram of FIG. 3, a flat disk-shaped disk 10 made of copper is fixed to a drive shaft 12 of a motor 11 and an alloy injection nozzle 14 for injecting an alloy 13 held therein with argon gas. On the other hand, they are arranged while maintaining an inclination angle of 30 degrees. In this state, the alloy 13 heated to a predetermined high temperature is extruded from the alloy injection nozzle 14 with an argon gas onto the rotating disk 10 at a predetermined speed, and is injected to produce spherical particles or fiber-like non-oxidized amorphous alloy. I have.

[0004]

The hydrogen storage alloy is used, for example, as a negative electrode of a nickel-metal hydride storage battery having a high energy density and capable of rapid charging and discharging. This hydrogen storage alloy controls the structure by cooling the molten metal from one direction and solidifying (unidirectionally solidified alloy), thereby controlling the structure to 1 to 10 μm.
Optimally, it should be a flat ribbon-like or flake-like solid state having a length of m and hold a plurality of streak-like grain boundaries formed substantially parallel to the length direction. . Hydrogen is absorbed and stored in the plurality of streak-like grain boundaries of the flakes, or has a property of discharging the stored hydrogen from the grain boundaries of the hydrogen storage alloy. When the shape of the hydrogen storage alloy is spherical grains, the grain boundaries are formed radially toward the center point of the spherical grains. However, in the case of spherical grains, the content density of hydrogen sucked into the grain boundaries becomes higher toward the center, and gradually larger internal stress is generated, eventually causing cracks and shortening the life of hydrogen storage. On the other hand, in the case of a ribbon-shaped or flake-shaped unidirectionally solidified alloy, a plurality of streak-like grain boundaries are formed in a substantially parallel state as described above. Can increase the repetition life.

However, in the case of powder production using a single roll shown in FIG. 2, when the molten alloy 1 is ejected from the nozzle 2 and collides with the peripheral surface of the cooling roll 5, the molten alloy 1 is centrifugally generated due to the rotation of the cooling roll 5. 1 is flipped off, and a part thereof is not formed into a ribbon shape but formed into a spherical particle. In the case of powder production using twin rolls, a similar problem occurs due to generation of centrifugal force due to rotation of the cooling roll.

In the case of powder production by the rotating disk method shown in FIG. 3, since the alloy 13 injected to the rotating disk 10 solidifies as a multilayer ingot, a substantially flat ribbon or flake required for a hydrogen storage alloy is used. It cannot be formed into a shape.

On the other hand, for example, a method of manufacturing a quenched metal ribbon by combining a single roll and a belt conveyor, for example, "Transportation and Apparatus of a Quenched Metal Strip" (Japanese Patent Application Laid-Open No. 5-277672) is disclosed. In this apparatus, as shown in the schematic diagram of FIG. 4, the molten metal ejected from the cooling nozzle 21 is rapidly cooled and solidified by the heat removal of the cooling roll 20 to form a rapidly cooled thin plate 22.
The thin plate 22 adhering to the cooling roll 20 is separated by air jetted from an air knife 23, and is guided by a magnetic force on a magnet conveyor 24 including an endless belt 24a, a magnet 24b, and a magnet roll 24c, and a pinch roll 25 for applying tension. Are transported to a winder (not shown) by a transport cart 28 having a blower 27 and a blower 27 mounted thereon, thereby producing a continuous ribbon without breakage. However, the above-described centrifugal force is generated when the molten metal is jetted from the cooling nozzle 21 to the cooling roll 20, and there is a problem that spherical particles are similarly formed. Therefore, the speed of the cooling roll is limited. There is also a problem that the configuration of the apparatus is complicated and the equipment cost is increased.

The present invention has been made to solve such a problem. That is, the object of the present invention is:
A quenched alloy foil strip manufacturing apparatus capable of reliably and quickly manufacturing a ribbon-shaped or flake-shaped hydrogen storage alloy having a thin thickness of a directionally solidified alloy foil strip, simplifying the manufacturing equipment and reducing equipment costs. It is to provide the method.

[0009]

According to the present invention, there is provided a tundish for holding molten metal therein and continuously dropping the molten metal from a lower nozzle, and a rotatable first and second rotatable metal member provided at a lower position of the molten metal below the nozzle. (1) a cooling roll, a rotatable second cooling roll disposed opposite to the first cooling roll, and an endless belt that is wrapped between the cooling rolls, tuned and rotated, and a quenched alloy foil strip is placed and transported. A tension roll disposed at a lower position between the cooling rolls to apply tension to the endless belt.

Further, according to the present invention, the first rotatable first metal provided at a drop position of the molten metal below the tundish for holding the molten metal therein and continuously dropping it from a lower nozzle is provided.
A cooling roll and a second cooling roll arranged opposite to the first cooling roll and tuned and rotated by an endless belt are arranged, and the molten metal dropped from the nozzle is placed on the endless belt stretched between the cooling rolls. A rapidly quenched alloy foil strip which is continuously quenched while being conveyed at a predetermined speed to produce a ribbon-shaped or flake-shaped alloy foil strip of a unidirectionally solidified alloy.

According to the apparatus and method of the present invention, since an endless belt having an infinite radius is stretched between two cooling rolls, the generation of centrifugal force due to the rotation of the cooling roll conventionally used is eliminated. Can be. Therefore, the molten metal (powder of the hydrogen storage alloy) due to the generation of the centrifugal force is not repelled, so that the formation of spherical particles can be prevented. Also, even if the molten metal held in the tundish falls from the nozzle onto the endless belt stretched between the cooling rolls, the lower surface of the molten metal comes into contact with the endless belt to ensure stable and stable cooling. While rapidly and continuously quenched, a substantially flat ribbon-shaped or flake-shaped alloy foil strip of the directionally solidified alloy can be formed. Further, since the conveying speed of the endless belt can be adjusted, it is possible to easily and quickly select and manufacture a thin ribbon or flake alloy as required.

Further, since the equipment for producing the directionally solidified alloy is composed of two cooling rolls, an endless belt and a tension roll, the equipment can be simplified and the equipment cost can be reduced. Further, since a predetermined tension can be easily applied to the endless belt by providing a tension roll, slipping of the endless belt can be prevented, and a thin ribbon-shaped or flake-shaped alloy foil strip of good quality can be manufactured.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In addition, the same reference numerals are given to the common parts in the respective drawings, and the duplicate description will be omitted. FIG. 1 is an overall configuration diagram of a quenched alloy foil strip manufacturing apparatus of the present invention. As shown in this figure, a quenched alloy foil strip manufacturing apparatus 30 of the present invention is a tundish in which a molten metal (hydrogen storage alloy) 34 is housed in a vacuum chamber 31 and is continuously dropped from a lower nozzle 33. 32, a rotatable first cooling roll 35 provided at a drop position of the molten metal 34 below the nozzle 33, a rotatable second cooling roll 36 disposed opposite to the first cooling roll 35, and a cooling roll 35 , 36, an endless belt 37 on which a quenched alloy foil strip (hydrogen storage alloy formed into a unidirectionally solidified alloy) 34 ′ which is tuned and rotated and placed is placed and transported;
A tension roll 38 disposed at a lower position between the cooling rolls 35 and 36 to apply a predetermined tension to the endless belt 37;
(Two in this figure).

The inside of the vacuum chamber 31 is evacuated by a vacuum pump (not shown) so that the inside of the vacuum chamber 31 is maintained at a high vacuum. Note that the vacuum chamber 31 may be filled with an inert gas such as argon.

With the above configuration, the cooling rolls 35, 3
Since the endless belt 37 with an infinite radius was stretched between 6
The generation of centrifugal force due to the rotation of the cooling roll conventionally used can be eliminated. Thereby, since the molten metal droplet is not repelled by the generation of the centrifugal force, the formation of spherical particles can be prevented, and a cooling foil strip suitable for creating a hydrogen storage alloy can be manufactured.

Further, even if the molten metal 34 held in the tundish 32 is dropped from the nozzle 33 onto the endless belt 37 extended between the cooling rolls 35 and 36, the lower surface of the molten metal comes into contact with the endless belt to ensure the reliability. The contact surface with the endless belt 37 can be rapidly and continuously cooled while being transported to form a substantially flat ribbon-like or flake-like alloy foil strip of the directionally solidified alloy 34 '. it can. Further, with respect to the first cooling roll 35 provided with a predetermined gap at the position where the molten metal 34 falls below the nozzle 33, the other second cooling roll 36 maintains a predetermined inclination angle. Since they are arranged, the one-way solidified alloy 34 ′ can be easily conveyed to the downstream side while being guided on the endless belt 37 without difficulty. Further, by adjusting the transport speed of the endless belt 37, it is possible to easily and quickly select and manufacture a thin ribbon-shaped or flake-shaped alloy foil strip having a different thickness as required.

Further, a facility for producing a unidirectionally solidified alloy foil strip is provided.
Since the cooling rolls 35 and 36, the endless belt 37, and the tension roll 35 are used, the equipment can be simplified, and the equipment cost can be reduced. Further, since the tension roll is provided, a predetermined tension can be easily applied to the endless belt, so that the endless belt can be prevented from slipping and a thin ribbon-shaped or flake-shaped alloy foil strip of good quality can be manufactured. it can.

Next, the method for manufacturing a rapidly quenched alloy foil strip of the present invention will be described with reference to FIG. Tundish 32 holding molten metal 34 inside and continuously dropping from lower nozzle 33
A first cooling roll 35 rotatably provided at a drop position of the molten metal 34 below the first cooling roll 35, and a second cooling roll 36 arranged opposite to the first cooling roll 35 and rotated in synchronization with an endless belt 37 are arranged. The dropped molten metal 34 is placed on an endless belt 37 stretched between cooling rolls 35 and 36, and then rapidly cooled while being conveyed at a predetermined speed to form a unidirectionally solidified alloy foil strip 34 '. Manufacture ribbon or flake alloy foil strips. By this method, a hydrogen storage alloy capable of storing a large amount of hydrogen can be continuously and efficiently produced.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the present invention.

[0020]

As described above, the quenched alloy foil strip manufacturing apparatus and method of the present invention can reliably and quickly manufacture a ribbon-shaped or flake-shaped hydrogen storage alloy having a thin unidirectionally solidified alloy foil strip. It has excellent effects such as simplification of manufacturing equipment and reduction of equipment cost.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a quenched alloy foil strip manufacturing apparatus of the present invention.

FIG. 2 is a schematic view of a conventional single roll method.

FIG. 3 is a schematic view of a conventional rotating disk method.

FIG. 4 is a schematic diagram in which a conventional single roll and a belt conveyor are combined.

[Explanation of symbols]

Reference Signs List 1 molten alloy 2 nozzle 3 base material 4 surface layer 5, 20 cooling roll 6, 13 alloy 7 ribbon-shaped permanent magnet material 10 disk 11 motor 12 drive shaft 14 alloy injection nozzle 21 cooling nozzle 22 quenched thin plate 23 air knife 24 magnet conveyor 24a , 37 Endless belt 24b Magnet 24c Magnet roll 25, 26 Pinch roll 27 Blower 28 Conveyor cart 30 Quenched alloy foil strip manufacturing device 31 Vacuum chamber 34 Molten metal (hydrogen storage alloy) 34 'Quenched alloy (formed in one-way solidified alloy) (Hydrogen storage alloy) 35 First cooling roll 36 Second cooling roll 38 Tension roll

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Norio Iwanami 1-term Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishikawashima Harima Heavy Industries, Ltd. F-term in the Yokohama Engineering Center (reference) 4E004 DB02 TA02 TA06 4K017 AA04 CA03 DA09 EC02

Claims (2)

[Claims] 1. A tundish holding molten metal inside and continuously dropping from a lower nozzle, a first cooling roll rotatably provided at a position where the molten metal falls below the nozzle, and a first cooling roll. A second cooling roll that is rotatably opposed to and disposed between the cooling rolls, an endless belt that is wrapped between the cooling rolls, tuned and rotated, and a quenched alloy foil strip is placed and conveyed, and disposed below the cooling rolls. And a tension roll for imparting tension to the endless belt. 2. A rotatable first cooling roll provided at a drop position of a molten metal below a tundish for holding the molten metal therein and continuously dropping the molten metal from a lower nozzle;
A second cooling roll is disposed opposite to the cooling roll and rotates synchronously with the endless belt. The molten metal dropped from the nozzle is placed on the endless belt stretched between the cooling rolls, and is conveyed at a predetermined speed. A quenched alloy foil strip which is continuously quenched to produce a ribbon-shaped or flake-shaped alloy powder material of a directionally solidified alloy.