JPS6233701A - Molding method for pulverous powder molding - Google Patents

Abstract

PURPOSE:To produce a molding having uniform quality with high efficiency by circulating a molding material together with a hard grinding medium in the state of jets in a grinding chamber to pulverize said material, sucking the pulverized material into metallic molds subjected to evacuation and packing and solidifying the pulverized material in a pressurized state. CONSTITUTION:A parting material is coated on the inside surface of perforated plates 15 in the metallic molds 11 and the wear-resistant fluid grinding medium such as superhard steel is put into the grinding chamber 5. The molding material (for example, Al2O3 powder) is supplied from a supply port 10 into the grinding chamber. A blower 8 and a vacuum pump 18 are started to eject air from a nozzle 9 and to evacuate the inside of the metallic molds 11. The air is spirally circulated toward A so as to collide alternately against upper and lower baffle plates 2, 3 and is sucked into the metallic molds 11. The molding material and the grinding medium are thereby brought into collision against each other and the material is pulverized by the collision against the baffle plates 2, 3 and the wall surface of the chamber 5. The pulverized material ascends into a diffusion chamber 4 from which the material is sucked together with the air into the metallic molds 11 and is packed and solidified in the pressurized state so as to be pressed to the perforated plates 15. The moldings are thus obtd. The moldings are taken out of the baffle plates 11 and are sintered in a sintering furnace.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for manufacturing parts in which a product is obtained by molding and sintering fine powder of metal or non-metal, in which fine powder is molded by pressurizing it in a mold. This invention relates to a method for forming a molded article.

[Conventional technology]

A method of manufacturing parts is known in which fine metal powder or fine non-metal powder mixed therein is pressurized and molded in a mold, and the molded product is taken out of the mold and sintered to obtain a product. Is this product porous? Do you have cutting processing? It is widely used in various fields because it fosters characteristics such as unnecessary. Especially ultrafine powder such as AkOs? In recent years, demand for ceramics for use in IC parts, parts for precision machinery, etc. has been increasing.

Conventionally, methods for manufacturing this type of parts include mechanical crushing,
The metal powder is crushed using physicochemical methods such as reduction and electrolytic methods, then filled into a mold, pressurized with a press or water pressure, etc. to form the product, and then the molded product is removed from the mold. The most popular method is sintering in a sintering furnace.

[Problems to be Solved by the Invention] However, in such conventional manufacturing methods, when molding the entire fine powder molded product, as described above, the fine powder is completely filled into the mold and pressurized by pressing or water pressure. Since F-forming was used for pressing, the transmission of pressure tends to be uneven, leading to problems such as the molded product becoming non-uniform, reducing the quality of the sintered body, and impairing dimensional accuracy. Tsuno.

The present invention was created in view of the above points, and its entire purpose is to provide a novel method for molding fine powder molded products that makes it possible to obtain molded products with uniform properties with high efficiency.

[Friendly means to solve all problems]

In order to achieve all of these objectives, the present invention circulates the molding material supplied into the crushing chamber and a hard fluidized crushing medium in a jet flow within the crushing chamber to pulverize the molding material. The mixture was filled by suction into the mold, which was depressurized using a vacuum device.

[For production]

When the molding material and the fluidized grinding medium circulate in the grinding chamber in a jet form with jet air, they are pulverized by friction with the fluidized grinding medium and collision with the outer wall of the grinding chamber, but at this time, the inside of the mold is depressurized by a vacuum device. As a result, the pulverized molding material is drawn into the mold by the pressure difference and is pressed against the inner wall surface of the mold, filling it under pressure and solidifying it. The molded product taken out from the mold is sent to a sintering process.

〔Example〕

Figures 1 and 2 are the tth diagrams illustrating the entire method for molding a fine powder molded product according to the present invention. Vertical section view. In the figure, a crushing tower 1 is formed into a closed cylindrical shape, and a collision plate 2 formed in the shape of an umbrella with a small diameter is installed in the middle and high part of the crushing tower 1. Further, at the bottom of the crushing tower 1, a lower collision plate 3 formed in a dish shape is installed. A diffusion chamber 4 and a crushing chamber 5 are separated above and below the collision plate 2, and at the center of the lower end of the crushing chamber 5 is a pulp 6? Between the growing piping 7 and the blower device 8? The connected nozzles 9 are opened upward. 'f: In the outer wall of the crushing chamber 5, a raw material supply port 10 for supplying powder of, for example, A1203 as a molding material is opened at the peripheral edge of the collision plate 3.

On the other hand, above the crushing tower 1, a plurality of molds 11 are connected to a diffusion chamber 4 through a pipe 13 for pulping 12 kN, and each mold 11 is used for molding the pulp as shown in FIG. It has a cavity 14 having the same shape as the product, and is formed in a t-half shape, and is clamped with a conventional mold clamping/opening device, a bolt, or the like. Maku,
The cavity 14 is lined with a perforated plate 15. 1
6 is a dust removal device connected to each mold 11 by an open pipe 1T, and a vacuum pump 18 is connected to the pipe 19.
It is configured to suck all the air inside the mold 11, remove dust, and then discharge it outside the machine.

A method of molding a fine powder molded product using the molding apparatus configured as described above will be explained. After applying a mold release agent such as a polyimide alcohol solution to the inner surface of the perforated plate 15 of a plurality of molds 11 having cavities 14 having the same shape as the molded product, pipes 13 and 17 are connected to the crushing tower 1 and the dust removal device 16. Connect with ′!
In the grinding chamber 5, a fluid grinding medium having a diameter of about 0.5 mm and having wear resistance such as diamond or super hard steel is placed. For example, At! as a molding material is supplied from the raw material supply port 10! After the powder of No. 03 is completely supplied, when the air blower and the vacuum pump 18 are fully started, the air ejected from the nozzle '9 collides alternately with the upper and lower collision plates 2 and 3 as shown by arrow A in the figure. At the same time, the air inside the mold 11 is sucked. For example, A t203 powder and diamond particles circulate together with air in the grinding chamber 5, causing mutual damage. ! A due to the collision between the collision plates 2 and 3 and the collision with the wall of the crushing chamber 5.
The t20s powder is pulverized to 1 μm or less. This fine powder rises from around the collision plate 2 into the diffusion chamber 4 and is sucked into the mold 11 together with air, and due to the reduced pressure inside the mold 11, the porous plate 1
The JN shaped product 20 is produced by being filled into the mold 11 under pressure so as to be extruded into the mold 11 and solidified.

On the other hand, the air discharged from the mold 1 is removed from the dust removal device 1.
After the dust 2 is removed at step 16, it is discharged outside the machine. After molding, the unsintered molded product is taken out by dividing it in half into the mold 11.
By sintering in a sintering furnace, a product of 9 AtzOs ceramics is obtained.

In this example, Al2O5 powder was used as the molding material, but other gold powders may also be used, or non-metallic powders may be mixed in.

〔Effect of the invention〕

As is clear from the following explanation, according to the present invention, as a method for molding a fine powder molded product, the molding material supplied into the crushing chamber and the hard flow-side crushing medium are circulated in the crushing chamber in a jet-like manner. Is there a method in which the molding material is pulverized by friction with the pulverizing media and by collision with the wall of the pulverizing chamber, and the pulverized powder is sucked into the mold, which has been depressurized by a vacuum cleaner, and then filled under pressure? As a result, the mold is uniformly filled with fine powder, which makes the molded product homogeneous and improves the quality of the product.The molding cycle can also be completed in a short time, improving productivity.

[Brief explanation of the drawing]

Fig. 1 shows the molding process, Fig. 2 shows I\Ik for explaining the entire molding method of the fine powder molded product according to the present invention, and Fig. 1 shows the molding equipment l.
Figure 2 is a vertical sectional view of the mold after molding. 1... Crushing base, 2, 3... Collision plate, 5...
Grinding chamber, 8... Air blower, 9... Nozzle, 10
...Raw material supply port, 11...Mold, 14 building...
Cavity, 18...Vacuum bonder, 20...φ molded product. Figure 1

Claims (1)

[Claims] The molding material supplied into the crushing chamber and the hard fluidized crushing medium are circulated in the crushing chamber in the form of a jet using jet air, and the molding material is pulverized by collision with the wall surface and friction between the molding material and the fluidized crushing medium. A method for molding a finely powdered molded product, which is characterized by sucking a finely divided molding material into a mold that has been depressurized using a vacuum device, and filling and solidifying it under pressure.