JPS62290806A - Production of metallic flake - Google Patents

Abstract

PURPOSE:To make mass production of uniform metallic flakes in a short period by ejecting a compressed gas to the molten metal flow dropped from plural conduits to pulverize the metal and bringing the pulverized metal into collision against the outside wall of a rotating cylinder, the inside of which is forcibly cooled, from the lateral side. CONSTITUTION:The molten metal 1 is put into a refractory vessel 2 and is held therein. The molten metal is dropped from the plural conduits 3 to create to fine flow of the molten metal 1. Nozzles 4 are respectively horizontally installed near the bottom ends of the respective conduits 3 to inject the pressurized gas to the molten metal flow, thereby pulverizing the metal. The pulverized metal 1 collides against the rotating cylinder 5 installed forward in the injecting direction of the pressurized gas. Since a cooling medium flows in the cylinder 1, the pulverized metal 1 is quickly solidified while flattened by the surface of the cylinder. Flattened and solidified metal 1 is scraped from the cylinder 5 by a wire brush 8 or the like. The scraped metals are captured and the metallic flakes having the uniform size and high quality are obtd.

Description

[Detailed Description of the Invention] & Detailed Description of the Invention [Industrial Application Field] The present invention provides a method for producing metal flakes suitable for producing large-sized metal flakes from molten metal.

[Conventional technology and problems]

Conventionally, in order to produce flaky metal elements or alloys (in the present invention, these are simply referred to as metals), for example, IJ obtained by cutting a metal ingot,) in-shaped cut pieces, or by rolling the metal. Thin flakes obtained by making molten metal fall onto a rotating disk as a trickle are made into thin flakes with a thickness of several microns or a few mm using stamp mills, Zeel mills, etc., and these are further divided into thin pieces. It is made of thin metal flakes.

These manufacturing methods involved many steps and were complicated, but the inventor first developed a method in which molten metal was dropped through a thin tube, and compressed gas ρ) was injected into the falling molten metal flow through a nozzle. However, they succeeded in easily obtaining metal flakes in a single step by colliding the pulverized bath water against a rotating disk (Japanese Patent Publication No. 16391/1983).

This method makes it possible to obtain metal flakes of various flatness qualities, and the equipment that implements this method has various advantages such as extremely low noise and vibration, but it is possible to obtain metal flakes in large quantities. In this case, it is difficult to increase the size of the device due to its structure, or, for example, if the structure is such that the IC thin tubes are arranged in the radial direction of a rotating disk, the rotating disk In addition to the different manufacturing conditions such as different circumferential speeds, there were also problems such as a decrease in the uniformity of the metal powder. Therefore, a large number of the same devices are required, which poses problems in terms of production efficiency and equipment costs.

[Purpose of the invention]

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a method for manufacturing metal flakes with extremely high production efficiency by which a large amount of metal flakes can be manufactured in a short time. There is one thing.

[Structure of the invention]

The object of the present invention is to drop molten metal through a plurality of conduits provided on both sides of a rotating cylinder whose inner surface is forcibly cooled, and jet compressed gas from nozzles from both sides to each falling molten metal flow. However, this can be achieved by a method for manufacturing metal flakes, which is characterized in that the molten metal flow is made to collide with the outer wall of a rotating cylinder while being pulverized.

Hereinafter, an apparatus implementing the method of the present invention will be described in detail with reference to Figure 10F.

As shown in Figure 1, put Kin 8 bath water 1 into a fireproof container 2 and use an appropriate strainer to keep it warm, and strain it to about 0.5 to 5 m1.
Create a trickle of molten metal through the yI conduit.

In addition, in this example, the bath water metal (metal and its alloy) is not limited to P#, but at 1400°C
The following low melting points are preferred.

On the other hand, by injecting pressurized gas through a nozzle 4 installed horizontally near the lower end of the conduit 6, the molten metal flow flowing out from the conduit 3 is pulverized. The compressed gas used here is, for example, air or a non-oxidizing gas such as nitrogen, carbon dioxide, arsenic, or argon, which is appropriately selected and used for the molten metal. The pulverized molten metal collides with a rotating cylinder 5 installed forward in the direction of pressurized gas injection. This rotating cylinder 5 is rotated by an IIA moving device (not shown) via, for example, a gear 10 provided on a rotating shaft 6, and a cooling medium flows inside the rotating cylinder 5.

The structure for flowing this coolant is, for example, by making the rotating cylinder 5 double-walled, and by feeding a coolant such as water into the rotating cylinder 5 from one side of the hollow rotating shaft 6, so that one rotation @ 6 It is acceptable to have a structure that discharges water from the air. In addition, at least the surface of the rotating cylinder 5 is required to have properties that are difficult to alloy with the molten sprayed metal, have heat resistance, and allow metal powder that collides and becomes flat to be easily peeled off. It is preferable to use a metal plate baked with ceramics or a thermosetting resin such as Teflon, silicone, or epoxy.

The 'Jr' collided with the rotating cylinder 5 which was being forcibly cooled as described above. The M-differentiated or slender molten metal is ``I'' on the cylindrical surface.
The scaly metal powder that has been rapidly cooled and solidified is in a state where it is extremely easy to peel off without being stuck on the cylinder surface. 7. It can be scraped off and collected very easily with a wire brush 8 or an air brush (not shown). Note that the metal powder layered on the cylinder surface is completely removed from the muff where the sprayed metal collides with it again. For example, wire brushes 8, etc., are installed in double or triple layers so that the brushes 8 can be dropped into the air.In addition, the casing housing the above-mentioned components is designed to reduce the pressure effect of the compressed gas ejected from the nozzle 4. For this purpose, for example, a suction port 9 for forced suction is provided.

A plurality of the above-mentioned conduits 3 are arranged along the axis of rotation of the rotating cylinder 50 at appropriate intervals, and the nozzles 4 are also arranged corresponding to the conduits 3. Therefore, by increasing the number of conduits 3 through which the molten metal flows out, it is possible to easily increase the amount of metal powder produced, and it is also possible to increase the amount of metal powder produced. For example, it is possible to obtain flat metal powder with a uniform size and quality even though the metal powder is manufactured in different time periods.

That is, this embodiment has a configuration using one rotating body such as the rotating cylinder 5, and the molten metal discharged from the plurality of conduits 3 is controlled by the rotational speed of the rotating cylinder 50, the degree of cooling, and the distance from the nozzle to the cylinder surface. There is 〒 because the distance etc. are processed under the same conditions.

Although a thin tube of about 0.5 to 5 mm yi was used as the conduit 3 in the above embodiment, the conduit of the present invention is not limited to a relatively thin tube within this range, and a thicker tube can also be used. . That is, depending on various conditions such as the gas pressure of the compressed gas, it is also possible to use a thick conduit.

Further, in the above embodiment, the number of nozzles 4 is equal to the number of conduits 6, but the present invention is not limited to this. A structure that can be covered by one nozzle with Of course, it is also possible to have a bottom structure in which a plurality of nozzles are appropriately arranged for one conduit 6.

The shape and size of the scaly metal powder obtained by the method of the present invention are determined by the temperature and thinness of the molten metal flow, the shape of the nozzle and the injection speed of the high-pressure gas, the distance from the nozzle to the surface of the rotating cylinder, and the distance between the nozzle and the surface of the rotating cylinder. The oxidation of the metal powder can be prevented by selecting the atomizing gas and the degree of cooling of the rotating disk, and if necessary, using an atomizing medium. It can also be completed.

〔Effect of the invention〕

As mentioned above, according to the proposed method, it is possible to easily obtain VC @ flaky metal powder directly from molten metal by setting appropriate conditions, and the thickness and size of the metal powder can be easily adjusted. Not only is it easy to use, but the time from molten metal to spray solidification is short without the use of mechanical operations or grinding aids, so by selecting a spray medium, you can efficiently produce high-quality metal powder with little surface oxidation and few impurities in a short time. You can get a lot of things! Wear. Moreover, the present invention eliminates the steps of cutting, rolling, and rolling and crushing that are used in the production of copper powder, brass powder, or aluminum powder for paints and pigments.
It is possible to eliminate pollution problems such as noise and vibration during spreading and crushing with 1% grinding.

As described above, the method of the present invention can produce a large amount of highly active metal powder with a large surface area and low surface oxidation in one step, making it an extremely useful manufacturing method in the field of manufacturing gold catalysts and organic metals. There is a ma.

[Brief explanation of the drawing]

FIG. 1 is an enlarged schematic diagram of one embodiment of the apparatus using the method of the present invention, FIG. 2 is a schematic side view of the entire apparatus shown in FIG. 1, and FIG. 6 is a schematic side view of the entire apparatus shown in FIG. 1. FIG. 1... Molten metal, 2... Fireproof container, 3...
Conduit, 4... Nozzle, 5... Rotating cylinder, 6...
・Rotating shaft, 7...Doctor, 8...Wire brush, 9...Suction port, 10...Gear. (2 other people> ”” d. Figure 1)

Claims (1)

[Claims] 1) Molten metal is dropped through a plurality of conduits installed on the side of a rotating cylinder whose inner surface is forcibly cooled, and compressed gas is applied to each falling molten metal flow from the side from a nozzle. A method for producing metal flakes, characterized in that the molten metal flow is pulverized and collided with the outer wall of a rotating cylinder. 2) The method for producing metal flakes according to claim 1, wherein the inner surface of the rotating cylinder is cooled by flowing a coolant through a coolant passage provided along the inner wall of the cylinder.