JPH07100805B2 - Metal powder manufacturing equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing a metal powder by injecting molten metal into a swirling moving cooling liquid layer.

[0002]

2. Description of the Related Art Rapidly solidified metal powders have fine crystal grains and can contain alloy elements in a supersaturated state. It has excellent material properties and is attracting attention as a material for machine parts.

A rotating drum method is a suitable method for producing the rapidly solidified metal powder. In this method, as shown in FIG. 3, the cooling liquid layer 62 is formed on the inner peripheral surface of the rotating cooling drum 61.
Is produced by the action of centrifugal force, the molten metal is injected into the cooling liquid layer 62, and finely divided to obtain a rapidly solidified metal powder. In the figure, 63 is an injection crucible as a molten metal injection means, a high frequency coil 64 for heating is attached to the outer peripheral surface thereof, and the injection nozzle 6 is provided on the lower side wall thereof.
5 has been opened. Molten metal 66 in the crucible 63
Is injected from the nozzle 65 by injecting an inert gas 67 into the crucible 63 under pressure. Then, when a certain amount of the metal powder in the cooling drum 61 is accumulated, the rotation of the cooling drum 61 is stopped, and the metal powder is collected together with the cooling liquid.
To be dried.

[0004]

However, in the rotary drum method, so-called batch type operation is performed and productivity is poor. Moreover, since the injection of the molten metal must be stopped when the powder is collected, there is a problem that the nozzle is likely to be clogged. Further, in order to keep the cooling temperature constant, it is necessary to supply and discharge the cooling liquid from the liquid surface of the cooling liquid layer to control the temperature, but at this time, the liquid surface is disturbed and the powder particle size and quality vary. There was a problem of easy occurrence.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a metal powder production apparatus capable of continuously producing metal powder of stable quality.

[0006]

The manufacturing apparatus of the present invention made to solve the above problems is provided with a cooling liquid jet pipe 7 for jetting and supplying the cooling liquid from the tangential direction along the inner peripheral surface. And a molten metal injection means 2 for injecting molten metal into the cooling liquid layer 21 formed on the inner peripheral surface of the cylindrical body 1 by the cooling liquid ejected from the cooling liquid ejection pipe 7. And a cooling liquid supply means 3 for supplying the cooling liquid to the cooling liquid ejection pipe 7, and a ring thickness adjusting ring 6A of the cooling liquid layer 21 is attached to the inner peripheral surface of the cylindrical body 1, A plurality of cooling liquid ejection pipes 7 are provided on the upper part thereof. In this case, the layer thickness adjusting ring 6B may be mounted between the adjacent stages of the cooling liquid ejection pipes 7.

[0007]

The cooling liquid ejected from the discharge port 8 of the cooling liquid ejection pipe 7 along the inner peripheral surface of the cylindrical body 1 flows down while swirling along the inner peripheral surface of the cylindrical body 1 for adjusting the layer thickness. The ring 6A overflows and flows downward. At this time, since a plurality of cooling liquid jetting pipes 7 are provided on the upper portion of the layer thickness adjusting ring 6A, the layer thickness of the cooling liquid layer 21 is increased due to the increase of the cooling liquid flowing speed at the upper portion of the ring 6A. The decrease can be prevented, and the cooling liquid layer 21 having a substantially constant inner diameter and a constant swirling flow velocity can be formed on the inner peripheral surface of the cylindrical body 1 in a long range. At this time, the thickness of the cooling liquid layer 21 and the stability of the flow velocity can be improved by mounting the layer thickness adjusting ring 6B also between the adjacent stages of the cooling liquid ejection pipes 7.

Since the cooling liquid layer 21 is always formed by a newly supplied cooling liquid, a constant temperature can be easily maintained. Therefore, it is not necessary to supply and discharge the cooling liquid from the liquid surface for temperature control, the liquid surface is less likely to be disturbed, and the stability is excellent. When the molten metal is injected and supplied to the inner peripheral surface of the upper cooling liquid layer 21, the molten metal is divided by the swirling flow, rapidly cooled and solidified, and the metal powder is continuously produced. Since this powder is formed by the cooling liquid layer 21 whose temperature and liquid surface state are stable and is sufficiently cooled, it has excellent quality stability.

[0009]

EXAMPLE FIG. 1 shows a metal powder manufacturing apparatus according to an example, in which a cooling cylinder 1 for forming a cooling liquid layer 21 for powdering and cooling on an inner peripheral surface, and a cooling liquid layer 21. An injection crucible 2 which is a means for injecting and supplying the molten metal 23 to the
A pump 3 as a means for supplying a cooling liquid to the cylindrical body 1 is provided.

The cylindrical body 1 has a cylindrical shape, and a lid 5 having an opening 4 of an appropriate size is centrally attached to the upper end of the cylindrical body 1. A plurality of discharge ports 8 of the cooling liquid ejection pipe 7 are opened on the inner peripheral surface of the cylindrical body 1, and the pipe axis direction of the ejection pipe 7 is set in a tangential direction slightly obliquely below the peripheral surface of the cylindrical body. There is. A ring thickness adjusting ring 6A of the cooling liquid layer 21 is attached to the inner peripheral surface of the lower portion of the cylindrical body 1 by bolts so as to be detachable and replaceable. The upper surface of the ring 6A is formed as a tapered surface whose diameter is reduced downward.

The number and the intervals of the cooling liquid jetting pipes 7 are the inner diameter of the cylinder, the discharge amount of the cooling liquid, the jetting pressure, and the layer thickness adjusting ring 6A.
Although it depends on the set distance and the like, the appropriate number of steps may be provided at substantially equal intervals so that the cooling liquid layer 21 having a substantially constant inner diameter can be obtained. A cylindrical draining net 9 is connected to the lower end of the cylindrical body 1, and a funnel body 10 for powder recovery is attached to the lower end thereof. A cover 11 is provided around the net body 9.

The cooling liquid jetting pipe 7 is connected to a tank 12 through a pump 3 by piping. Also, the cover 1
The bottom of 1 is piped to the tank 12, and the cooling liquid collected by the cover 11 is returned to the tank 12 and is circulated and used. Incidentally, the tank 12 is provided with a replenishing cooling liquid supply pipe (not shown), and a cooler may be appropriately interposed in the tank or in the middle of the circulation flow path. Water is generally used as the cooling liquid.

An injection crucible 2 as a molten metal supply means is provided on the upper portion of the lid 5, a heating coil 14 is wound around the outer periphery thereof, and a nozzle hole 15 is formed at the bottom thereof. Has been done. The injection crucible 2 has Ar or N ₂
Inert gas such as the above and molten metal are pressure-fed, and the molten metal 23 in the crucible 2 is injected into the cooling liquid layer 21 from the nozzle hole 15.

To carry out the present invention, first, the pump 3 is operated to form a cooling liquid layer 21 on the inner peripheral surface of the cylindrical body 1 which flows down while swirling at high speed. Next, Ar gas or the like is pressure-fed to the injection crucible 2 provided in the upper part of the cylindrical body 1, and the molten metal 23 in the crucible 2 is injected from the nozzle hole 15 toward the inner surface of the upper part of the cooling liquid layer 21. The injected molten metal flow is pulverized and rapidly solidified by the swirling flow of the cooling liquid layer 21 having a substantially constant layer thickness and flow velocity, and is sufficiently cooled while flowing down the cooling liquid layer 21. A powder having a uniform size and a substantially constant particle size is produced.

The rapidly solidified metal powder is sent to the net 9 through the lower end opening of the cylinder 1 together with the cooling liquid forming the cooling liquid layer 21. By the action of the centrifugal force of the cooling liquid itself, most of the cooling liquid is separated and discharged in the radial direction by the action of the centrifugal force of the cooling liquid itself. On the other hand, the metal powder that has been primarily deliquored by the mesh body 9 is discharged through the funnel body 10 and sequentially subjected to an appropriate deliquoring device such as a centrifuge, so that the liquid content almost disappears in a short time. Easily dried to product powder.

FIG. 2 shows a metal powder manufacturing apparatus according to another embodiment, and the same members as those in the first embodiment are designated by the same reference numerals. In this example, the layer thickness adjusting rings 6B are also mounted between adjacent stages of the cooling liquid ejection pipes 7 provided in plural stages. Thereby, the layer thickness and the flow velocity of the cooling liquid layer 21 can be further stabilized.

[0017]

As described above, in the metal powder manufacturing apparatus of the present invention, the layer thickness adjusting ring for the cooling liquid layer is attached to the inner peripheral surface of the cylinder, and the ring is connected to the upper portion along the peripheral surface of the cylinder. Since a plurality of cooling liquid ejection pipes for ejecting and supplying the cooling liquid from the direction are provided, a cooling liquid layer having a long cooling section can be easily formed with a substantially constant inner diameter, a constant temperature, and a constant flow velocity. Therefore, by injecting the molten metal into the cooling liquid layer, the rapidly solidified powder having a constant quality, which is pulverized under a certain condition and sufficiently cooled, is continuously produced, and the injection nozzle is not clogged.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view of a main part of a metal powder manufacturing apparatus according to an embodiment.

FIG. 2 is a cross-sectional explanatory view of a main part of a metal powder manufacturing apparatus according to another embodiment.

FIG. 3 is an explanatory cross-sectional view of a main part of a conventional metal powder manufacturing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling cylinder 2 Injection crucible (molten metal injection means) 3 Pump (cooling liquid supply means) 6A Layer thickness adjusting ring 6B Layer thickness adjusting ring 7 Cooling liquid ejection pipe 9 Liquid draining net 21 Cooling liquid layer

Claims (2)

[Claims] 1. A cooling cylinder (1) provided with a cooling liquid jet pipe (7) for jetting and supplying a cooling liquid from a tangential direction along an inner peripheral surface, and the cooling liquid jet pipe (7). Molten metal jetting means (2) for jetting molten metal to the cooling liquid layer (21) formed on the inner peripheral surface of the cylindrical body (1) by the cooling liquid jetted from the cooling liquid jetting pipe ( 7) is provided with a cooling liquid supply means (3) for supplying a cooling liquid, and a ring (6A) for adjusting the layer thickness of the cooling liquid layer (21) is attached to the inner peripheral surface of the cylindrical body (1). The metal powder manufacturing apparatus is characterized in that a plurality of cooling liquid ejection pipes (7) are provided on the upper portion thereof. 2. The apparatus for producing metal powder according to claim 1, wherein a layer thickness adjusting ring (6B) is mounted between adjacent stages of the cooling liquid jetting pipes (7).