Apparatus and method for manufacturing thin alloy ribbon

Abstract

An apparatus 1 for manufacturing a thin alloy ribbon includes: a tapping nozzle 35 for tapping molten alloy M; and a cooling roll 40 arranged so that the outer peripheral surface faces the tapping nozzle 35. On the rotating cooling roll 40, an alloy ribbon T is formed by tapping the molten alloy M from the tapping nozzle 35 and rapidly cooling same, and the thin alloy ribbon T is peeled off from the cooling roll 40 to fly for collection. The apparatus further includes a storage body 50, the inside of which is maintained in an inert gas atmosphere. The storage body 50 includes: a cooling part 54 with which the thin alloy ribbon T flying from the cooling roll 40 collides; and a discharge part 52a for discharging the thin alloy ribbon T, which has dropped due to collision with the cooling part 54.

Description

Alloy ribbon manufacturing apparatus and manufacturing method

[0001] The present invention relates to an apparatus and method for producing an alloy ribbon.

[0002] In recent years, iron-based amorphous alloys, whose main raw materials are iron (Fe), boron (B), and silicon (Si), have been used for various passive elements such as inductors and reactors used as electronic components, as well as for transformers. A widely known method for producing amorphous alloys is the melt spinning method, in which molten metal is sprayed from a nozzle onto a rotating roll and then rapidly cooled to produce an amorphous alloy ribbon.

[0003] For example, Patent Document 1 discloses an apparatus in which molten metal in a molten metal storage container is poured from a pouring nozzle onto the surface of a water-cooled roll provided in a quenching tank into which an inert gas is supplied, and the molten metal is rapidly cooled and solidified by rapid rotation of the water-cooled roll to continuously produce amorphous alloy ribbons in the quenching tank, and the resulting broken pieces are then compressed and discharged from the quenching tank.

[0004] Japanese Patent Application Publication No. 8-277403

[0005] The apparatus disclosed in the above-mentioned Patent Document 1 maintains an inert gas atmosphere in a quenching tank to prevent oxidation when the molten metal is quenched on the surface of a water-cooled roll to produce an alloy ribbon. However, when the thickness of the alloy ribbon is relatively large or when the alloy composition of the alloy ribbon has a low amorphous phase forming ability, it becomes difficult to sufficiently cool the entire alloy ribbon by the water-cooled roll, which poses a problem that the quenching tank needs to be enlarged to ensure the cooling time of the alloy ribbon.

[0006] SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus and method for producing an alloy ribbon that can produce a high-quality alloy ribbon with a compact configuration.

[0007] The above-mentioned object of the present invention can be achieved by an alloy ribbon manufacturing apparatus comprising a discharge nozzle for discharging molten alloy and a cooling roll arranged so that its outer peripheral surface faces the discharge nozzle, wherein the molten alloy is discharged from the discharge nozzle onto the rotating cooling roll to form an alloy ribbon by rapid cooling, and the alloy ribbon is recovered by peeling off the cooling roll and flying, the apparatus further comprising a container whose interior is maintained in an inert gas atmosphere, the container comprising a cooling section with which the alloy ribbon flying from the cooling roll collides, and a discharge section which discharges the alloy ribbon that collides with the cooling section and falls.

[0008] The alloy ribbon manufacturing apparatus may further include a winding device that winds the alloy ribbon discharged from the discharge section onto a bobbin.

[0009] The cooling section is preferably formed in a flat plate shape and is preferably arranged along the wall surface of the container.

[0010] The container preferably has a lower portion tapered downward, and the discharge portion is preferably formed at the lowest end of the container.

[0011] The container preferably has a peeling nozzle disposed therein for spraying an inert gas to peel the alloy ribbon from the cooling roll.

[0012] Furthermore, the above-mentioned object of the present invention can be achieved by a method for manufacturing an alloy ribbon, comprising the steps of: discharging a molten alloy from a dispensing nozzle onto a rotating chill roll and rapidly cooling it to form an alloy ribbon; peeling the alloy ribbon from the chill roll and causing it to fly; and cooling the alloy ribbon flying from the chill roll by colliding it with a cooling section in an inert gas atmosphere.

[0013] According to the alloy ribbon manufacturing apparatus and manufacturing method of the present invention, a high-quality alloy ribbon can be manufactured with a compact configuration.

[0014] 1 is a schematic configuration diagram of an alloy ribbon manufacturing apparatus according to an embodiment of the present invention.

[0015]

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a schematic diagram of an alloy ribbon manufacturing apparatus according to one embodiment of the present invention. As shown in Fig. 1, the alloy ribbon manufacturing apparatus 1 includes a tilting furnace 10, a hot water storage tank 20, a pressurizing tank 30, a cooling roll 40, a container 50, and a winding device 60.

[0016] The tilting furnace 10 heats raw materials placed in a crucible 11 made of alumina, SiC, or the like with an induction heating coil 12 and melts them in an inert gas atmosphere such as argon gas, to produce a molten alloy M. The crucible 11 is supported so as to be tiltable about a tilting axis 13, and the molten alloy M can be supplied to a storage tank 20 by tilting the crucible 11.

[0017] The molten alloy M supplied from the tilting furnace 10 to the crucible 22 through the opening 21 a is heated by an induction heating coil 23 to maintain the temperature of the molten alloy M. The opening 21 a can be sealed with a sealing lid 24.

[0018] The crucible 22 is equipped with a filter 25 for filtering the molten alloy M and a discharge tube 26 for discharging the molten alloy M from the bottom, and by supplying an inert gas such as argon gas under pressure into the casing 21 with the sealing lid 24 closed, the molten alloy M is supplied to the pressurized tank 30 via the discharge tube 26. The discharge tube 26 can be opened and closed by operating a molten alloy introduction valve 27.

[0019] The pressurized vessel 30 has a tundish 32 disposed within a casing 31, and the molten alloy M supplied to the tundish 32 from a discharge tube 26 inserted into the top opening of the casing 31 is heated by high-frequency induction heating or an electric heater 33 made of a Kanthal heater, SiC, or the like, to maintain the temperature of the molten alloy M. The pressurized vessel 30 is supported by an elevator (not shown) so as to be movable up and down, and the discharge tube 26 can be detached from the casing 31 by lowering the pressurized vessel 30, allowing replacement or maintenance of the pressurized vessel 30 to be performed.

[0020] The tundish 32 has a mechanism for maintaining the temperature of the molten alloy M by arranging heaters such as Kanthal heaters or SiC heaters around it, and also has a filter 34 for filtering the molten alloy M and a discharge nozzle 35 consisting of a BN nozzle or the like for discharging the molten alloy M from the bottom, and the molten alloy M is ejected from the discharge nozzle 35 by supplying pressurized inert gas such as argon gas into the casing 31. The discharge nozzle 35 has electric heaters 36 such as Kanthal heaters arranged around it, and can be opened and closed by raising and lowering a nozzle stopper 37.

[0021] The chill roll 40 is configured to be water-coolable, is disposed so that its outer peripheral surface 41 faces the tapping nozzle 35, and is driven to rotate in the direction indicated by the arrow around a rotation axis 42. The molten alloy M tapped from the tapping nozzle 35 is quenched on the rotating chill roll 40, and an alloy ribbon T is formed.

[0022] The container 50 is configured such that an upper member 51 and a lower member 52, each having an internal storage space, are in communication with each other. A receiving port 51a capable of partially receiving the cooling roll 40 is formed in the side wall of the upper member 51, and the alloy ribbon T formed on the cooling roll 40 is introduced into the upper member 51 through the receiving port 51a.

[0023] A peeling nozzle 53 is provided inside the upper member 51, which sprays an inert gas such as nitrogen gas to peel the alloy ribbon T from the chill roll 40. The inert gas sprayed from the peeling nozzle 53 is discharged to the outside through a gap between the chill roll 40 and the periphery of the receiving port 51 a, for example.

[0024] A cooling section 54 facing the outer peripheral surface 41 of the chill roll 40 is provided inside the upper member 51. The cooling section 54 is formed in a flat plate shape and is arranged along the inner wall surface of the upper member 51 so that the alloy ribbon T peeled off from the chill roll 40 and flying collides with the cooling section 54. The cooling section 54 is made of a metal material with high thermal conductivity, such as copper, and can be cooled by water cooling or the like.

[0025] The lower member 52 is formed in a conical shape tapering downward, and its bottom end is open to form a discharge portion 52a. A gas inlet 52b and a gas outlet 52c are formed in the upper and lower parts of the lower member 52, respectively. By operating a pump 56 provided in the circulation line 55, an inert gas such as argon gas is introduced through the gas inlet 52b and discharged through the gas outlet 52c, and circulated. The alloy ribbon T cooled in the container 50 is discharged from the discharge portion 52a.

[0026] The winding device 60 includes a disk-shaped support 61 rotatably supported around a rotation shaft 62, and a plurality of bobbins 63 rotatably supported on the support 61. Each bobbin 63 is driven to rotate in the direction of the arrow by a drive device (not shown) at the winding position P, thereby winding up the alloy ribbon T discharged from the discharge portion 52a.

[0027] Next, a method for producing an alloy ribbon using the alloy ribbon production apparatus 1 having the above-described configuration will be described. First, in the tilting furnace 10, an Fe-based alloy ingot, which is a raw material blended to a predetermined composition ratio, is melted while flowing argon gas to produce a molten alloy M. Next, argon gas is supplied into the casing 21 of the molten alloy storage tank 20, and the molten alloy M is supplied from the tilting furnace 10 to the molten alloy storage tank 20 with the molten alloy introduction valve 27 closed. After that, the sealing lid 24 is closed, and the molten alloy M is heated and maintained in the molten alloy storage tank 20 in an inert gas atmosphere.

[0028] Next, argon gas is supplied into the casing 31 of the pressurized vessel 30 to create an inert atmosphere inside, and the tundish 32 is preheated to a heating temperature of, for example, 1400°C or higher by energizing the electric heater 33. A nozzle cap (not shown) having an electric heater such as a Kanthal heater is attached to the molten metal discharge nozzle 35, and by energizing the nozzle cap and the electric heater 36 together, the molten metal discharge nozzle 35 is preheated to a heating temperature of, for example, 1200°C or higher. Thereafter, the nozzle cap is removed, and the molten metal introduction valve 27 is opened, thereby supplying a predetermined amount (e.g., 50 kg) of molten alloy M from the molten metal storage tank 20 to the pressurized vessel 30 and heating it in the pressurized vessel 30.

[0029] When the temperature of the molten alloy M in the tundish 32 reaches the tapping temperature, the atmospheric pressure of the argon gas in the casing 31 is increased to a predetermined injection pressure (e.g., 10-50 kPa), and the nozzle stopper 37 is raised, thereby starting the tapping of the molten alloy M from the tapping nozzle 35. In this way, the molten alloy M is tapped from the tapping nozzle 35 onto the rotating chill roll 40, and the process of forming an alloy ribbon T by quenching is performed.

[0030] The amount of the molten alloy M in the pressurized tank 30 that is reduced by tapping can be replenished from the molten alloy storage tank 20 by increasing the pressure in the molten alloy storage tank 20 to a predetermined level by supplying pressurized argon gas and adjusting the opening of the molten alloy introduction valve 27. In addition, the molten alloy M can be replenished in the molten alloy storage tank 20 by appropriately melting the raw materials in the tilting furnace 10.

[0031] The alloy ribbon T formed on the chill roll 40 is introduced into the container 50 by the rotation of the chill roll 40, and is peeled off from the chill roll 40 by the injection of nitrogen gas from the peeling nozzle 53. In this way, the process of peeling off the alloy ribbon T from the chill roll 40 and flying is performed.

[0032] The alloy ribbon T peeled off from the cooling roll 40 and flying away collides with the cooling section 54, and is then discharged from the discharge section 52a. During cooling of the alloy ribbon T inside the container 50, an inert gas atmosphere is maintained by circulating nitrogen gas sprayed from the peeling nozzle 53 and argon gas by operating the pump 56. In this way, the alloy ribbon T flying away from the cooling roll 40 is cooled by colliding with the cooling section 54 under the inert gas atmosphere.

[0033] In order to prevent the alloy ribbon T from being pulverized when it collides with the cooling section 54, the alloy ribbon T formed on the cooling roll 40 is preferably an Fe-based alloy such as an Fe—Si alloy or an Fe—B alloy having an amorphous structure excellent in strength and viscous toughness. More specifically, the composition of the molten alloy M forming such an alloy is, for example, Fe, balance Si, which is an alloy composition with low amorphous formation ability. 12.15 Atomic %, Fe balance B ｘ Si yExamples of the alloy composition include an alloy composition expressed by a composition formula in atomic percent that satisfies 10.0≦x≦15.0 and 0≦y≦3.0.

[0034] Furthermore, if the peripheral speed of the cooling roll 40 is too fast, the impact when the alloy ribbon T collides with the cooling section 54 becomes large, and the alloy ribbon T becomes easily damaged, whereas if the peripheral speed is too slow, it becomes difficult to obtain the desired amorphous (non-crystalline) structure. ３ ~10 ７ This can be easily maintained in the range of K / sec.

[0035] The leading end of the alloy ribbon T discharged from the container 50 is set in the winding device 60 and wound around the bobbin 63 at the winding position P. As a result, tension is gradually applied to the alloy ribbon T from the slack state immediately after collision with the cooling section 54, and the alloy ribbon T is reliably guided to the winding device 60 via the discharge section 52a and collected. After the winding of a predetermined length of the alloy ribbon T is completed, the support 61 is rotated in the direction indicated by the arrow to move the next bobbin 63 to the winding position P, and winding of the alloy ribbon T by this bobbin 63 is started, and the bobbin 63 on which the winding of the alloy ribbon T has been completed is replaced with a new bobbin 63. By repeating these operations in the winding device 60 until the supply of the molten alloy M from the pressurized tank 30 is completed, the alloy ribbon T can be wound and collected around a plurality of bobbins 63.

[0036] According to the alloy ribbon manufacturing apparatus 1 of this embodiment, when the alloy ribbon T formed on the cooling roll 40 is wound up by the winding device 60, a portion of the alloy ribbon T is maintained in contact with the cooling section 54 in an inert gas atmosphere, thereby enabling the configuration to be made compact while reliably preventing oxidation of the alloy ribbon T until it is sufficiently cooled, thereby enabling high-quality alloy ribbon T to be obtained.

[0037] REFERENCE SIGNS LIST 1 Alloy ribbon manufacturing apparatus 10 Tilting furnace 20 Hot water storage tank 30 Pressurized tank 35 Melt discharge nozzle 40 Cooling roll 50 Container 52a Discharge section 54 Cooling section 60 Winding device 63 Bobbin M Molten alloy T Alloy ribbon

Claims

1. An apparatus for manufacturing alloy ribbons, comprising: a dispensing nozzle for dispensing molten alloy; and a cooling roll arranged so that its outer peripheral surface faces the dispensing nozzle; the apparatus dispenses the molten alloy from the dispensing nozzle onto the rotating cooling roll to form an alloy ribbon by quenching, and recovers the alloy ribbon by peeling it off the cooling roll and flying it; the apparatus further comprises a container the interior of which is maintained in an inert gas atmosphere; the container comprises a cooling section with which the alloy ribbon flying from the cooling roll collides, and a discharge section which discharges the alloy ribbon that collides with the cooling section and falls.

2. The alloy ribbon manufacturing apparatus according to claim 1, further comprising a winding device for winding the alloy ribbon discharged from the discharge section onto a bobbin.

3. The alloy ribbon manufacturing apparatus according to claim 1, wherein the cooling section is formed in a flat plate shape and is arranged along the wall surface of the container.

4. An alloy ribbon manufacturing apparatus according to claim 1, wherein the container has a lower portion tapered downward, and the discharge portion is formed at the lowest end of the container.

5. An alloy ribbon manufacturing apparatus according to claim 1, wherein a peeling nozzle is provided inside the container for spraying an inert gas to peel the alloy ribbon from the cooling roll.

6. A method for manufacturing an alloy ribbon, comprising the steps of: discharging a molten alloy from a dispensing nozzle onto a rotating chill roll and rapidly cooling it to form an alloy ribbon; peeling the alloy ribbon from the chill roll and causing it to fly; and cooling the alloy ribbon flying from the chill roll by colliding it with a cooling section in an inert gas atmosphere.

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