KR100366774B1 - Device for producing ultra fine metal powder products - Google Patents

Abstract

The present invention uses the raw material for the production of metal injection molding raw material chamber 11 having a glove box 41 for manual work; A storage chamber 12 for storing and weighing ultra-fine metal powder and having a glove box 41 for manual operation and an inlet 32 for entering and exiting an object; A forming chamber 13 for use in forming and sintering ultra-fine metal powder and having a glove box 41 for manual operation and an inlet 33 for entering and exiting an object; Passages (21) (22) (23) (24) installed to communicate with the raw material chamber (11), the storage chamber (12), and the molding chamber (13) in a row, and having doors open and closed at both ends thereof; And a vacuum pump 50 for evacuating the raw material chamber 11, the storage chamber 12, and the molding chamber 13, a gas tank 60 for injecting an inert or protective gas, a pressure gauge for detecting vacuum and gas pressure. And an atmosphere adjusting means including the valves 43 and 44 for controlling the flow path.

Accordingly, it is cheaper than the ultra-high vacuum equipment and has a low maintenance cost, thus industrialization is possible, and the product can be manufactured without being constrained by the ultrafine metal powder production method without oxidation contamination of the ultrafine metal powder.

Description

Device for producing ultra fine metal powder products

The present invention relates to an ultra-fine metal powder product manufacturing apparatus, and more particularly, it is possible to industrialize because of the low cost and low maintenance cost compared to the ultra-high vacuum device, and is not limited to the ultra-fine metal powder production method. The present invention relates to an ultrafine metal powder product manufacturing apparatus capable of producing a product without oxidation contamination.

Nanometal powder is generally a material having a particle size of 0.1 μm or less, and has new and excellent properties which do not appear in conventional metal powder. Because of these excellent characteristics, researches on nano metal powders have been conducted for many years in Korea as well as in developed countries.

At present, the domestic level of nano metal powder is pilot plant stage in some companies such as Nanotech, and it is produced and applied in powder form in developed countries, but it cannot be industrialized by the bulk material with structure. Staying. One of the reasons is that even though the metal powder having a particle size of 30 nm or less was manufactured in order to obtain more excellent characteristics, the oxidation and ignition problems caused by particle micronization were not solved.

Conventional methods of manufacturing bulk materials using nanometal powders (laboratory research levels) have only been made as general glove boxes by preparing nanometal powders to reduce exposure time to the atmosphere and placing them in containers filled with inert gas. It goes into the molding and takes it out again to heat treatment.

In this way, the problem of ignition of nano metal powder was solved. However, the problem is that it is difficult to avoid exposure to the atmosphere for a short time in the process of the container, the oxidation reaction occurs and the inert gas must continue to flow. In addition, when molded and taken out, it is oxidized while being exposed to the atmosphere. Oxidized and contaminated raw materials require a separate process to remove oxides, and the added value is lowered because the performance of the product is degraded. The failure to industrialize the production of bulk materials using nanometal powders is due to the lack of solutions to oxidation problems.

Therefore, in order to manufacture bulk materials using nanometal powders, there is an urgent need for a device capable of manufacturing raw metal injection molding (Feedstock) and pre-sintered products from oxidation of nanometal powders. Feedstock and presinter are stable in the air.

To prevent oxidation or ignition of ultrafine metal powders produced by inert gas condensation or chemical vapor condensation, ultra-high vacuum equipment is often used to collect, form and sinter powders. Ultra-high vacuum equipment is generally very expensive. Therefore, it requires a lot of equipment investment cost and high technical skills as well as high cost to maintain ultra-high vacuum.

As such, huge production investment and maintenance costs inevitably raise the production cost of the product and lower the price competitiveness.

Therefore, an object of the present invention is to solve the above problems, and it is possible to industrialize because of the low cost and low maintenance cost compared to the ultra-high vacuum apparatus, and is not restricted by the ultrafine metal powder production method and without oxidation pollution of the ultrafine metal powder. Provided is an ultrafine metal powder product manufacturing apparatus capable of manufacturing a product.

1 is a block diagram schematically showing the apparatus according to the invention from the front,

FIG. 2 is a schematic view schematically showing the apparatus of FIG. 1 in plan view; FIG.

Figure 3 is a graph showing the comparison of the results of the oxidation analysis by the X-ray diffraction method in the embodiment using the apparatus of the present invention and a comparative example thereof.

Explanation of symbols on the main parts of the drawings

11, 12, 13: chamber 21, 22, 23, 24: passage

32, 33: opening 41: glove box

42: pressure gauge 43, 44: valve

45: monitoring window 50: vacuum pump

60 gas tank

In order to achieve the above object, the present invention is for use in the manufacture of raw materials for metal injection molding, and includes a glove box 41 for manual work, and has a raw material chamber 11 having a passage 21 leading to the outside on one side wall. It is used for storing and weighing ultra-fine metal powder, and includes a glove box 41 for manual operation and an inlet 32 for entering and exiting an object, and one side wall is sealed to the other side wall of the raw material chamber 11. Storage chamber 12 having a communication passage 22; It is used for forming and sintering ultra-fine metal powder, and includes a glove box 41 for manual work and an inlet 33 for entering and exiting an object, and having one side wall. A molding chamber 13 having a passage 23 sealingly communicating with the other side wall of the storage chamber 12, the other side wall having a passage 24 communicating with the outside; the raw material chamber 11, It communicates with the storage chamber 12 and the molding chamber 13, respectively, A vacuum pump 50 for exhausting the gas tank 60 communicating with the raw material chamber 11, the storage chamber 12, and the molding chamber 13 to inject an inert or protective gas therein; A pressure gauge (42) connected to each of the chamber (11), the storage chamber (12), and the shaping chamber (13) to detect vacuum and gas pressure inside the chambers (11) (12) (13); And connecting tubes between the chambers 11, 12, 13 and the vacuum pump 50, and connecting tubes between the chambers 11, 12, 13 and the gas tank 60. Valves 43 and 44 installed at and intercepting the flow path, wherein the passages 21, 22, 23, 24 have doors open and closed at both ends, respectively, and the storage The nanometal powder production apparatus 71 is hermetically communicated with the inlet 32 of the chamber 12, and the sintering apparatus 72 is hermetically communicated with the inlet 33 of the molding chamber 13. In addition, the vacuum pump 50, the gas tank 60, the pressure gauge 42 and the valves 43, 44 are through the passages 21, 22, 23, 24, the raw material chamber ( 11), the storage chamber 12, the molding chamber 13, characterized in that the exhaust or gas injection is made.

At this time, the atmosphere control means is such that the exhaust or gas injection to the raw material chamber 11, the storage chamber 12, the molding chamber 13 through the passage (21) 22 (23) (24).

The core of the present inventors integral cleaning device is that the device can stably handle the nano metal powder and can produce the bulk material without oxidation. The design concept of the cleaning device is to manufacture nanometal powder, and then to continuously feed in an inert or protective gas atmosphere with an organic binder on the nanometal powder to produce a feedstock for metal injection molding or to form and manufacture nanometal powder. By pre-sintering to make a bulk material, it is possible to produce a product free from oxidation pollution. The present invention is mainly applicable to the production of small and functional articles. These products are small in volume and can create high added value, so they can be manufactured with venture-scale devices. Feedstock for metal injection molding is stable because the powder surface is coated with an organic binder. However, since the raw material for metal injection molding is manufactured by heating to 150 ° C. or higher, when the nano metal powder is used, this clean device is essential. The present invention relates to a nano-metal powder product manufacturing apparatus containing the above concept.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a schematic view showing the apparatus according to the present invention from the front, and FIG. 2 is a schematic view showing the apparatus of FIG.

The raw material chamber 11 is used for manufacturing a metal injection molding feedstock and has a glove box 41 for manual operation. The raw material chamber 11 is a process chamber for mixing ultra-fine metal powder with an organic binder for metal injection molding. The storage chamber 12 is for ultra-fine metal powder storage and weighing, and has a glove box 41 for manual operation and an inlet 32 for entering and exiting an object. The storage chamber 12 is a process chamber which takes powder from an ultrafine metal powder production apparatus and stores it in a container or measures the amount of powder. The forming chamber 13 is used for forming and sintering ultra-fine metal powder and includes a glove box 41 for manual operation and an inlet 33 for entering and exiting an object. Glove box 41 refers to a glove-type mechanism that can be put in the hands of the worker from the outside to work in the interior space.

The monitoring window 45 is installed on the front of each of the chambers 11, 12 and 13 so that the worker can work by using the glove box 41 while looking inside. The openings 32 and 33 installed in the storage chamber 12 and the molding chamber 13 are doors installed and openable.

In addition, according to the present invention, passages 21, 22, 23, 24 having doors open and closed at both ends communicate with the raw material chamber 11, the storage chamber 12, and the molding chamber 13 in a row. To be installed. That is, the raw material chamber 11 and the storage chamber 12 communicate with each other, and the storage chamber 12 and the molding chamber 13 communicate with each other. The passages 21, 22, 23, 24 are simple pipe-type connecting devices, which can be increased or decreased by an appropriate number depending on the powder production method.

At this time, the passages 21, 22, 23, 24 are provided to isolate the process chambers and to prevent contamination by impurities that may be discharged from the respective processes. Doors installed at both ends of 24) require airtightness and can be opened and closed from both inside and outside. In this way, the process chamber from which the pollutant such as vaporized organic matter is discharged is separated from the process chamber requiring cleanness.

Further, according to the present invention, the raw material chamber 11, the storage chamber 12, the vacuum pump 50 for evacuating the forming chamber 13, the gas tank 60 for injecting inert or protective gas, vacuum and gas pressure And an atmosphere adjusting means having a pressure gauge 42 for detecting the oil, a valve 43 and 44 for controlling the flow path, and the like. Pressure gauges 42 use photohelical instruments and valves 43 and 44 use solenoid valves. Using the vacuum pump 50 and the gas tank 60 to supply the argon gas, the gas inside the chambers 11, 12, 13 is automatically replaced, and when the argon gas pressure is lowered, it is continuously replenished. Can be maintained.

At this time, the atmosphere control means is such that the exhaust or gas injection to the raw material chamber 11, the storage chamber 12, the molding chamber 13 through the passage (21) 22 (23) (24). The vacuum pump 50 and the gas tank 60 are connected to the passages 21, 22, 23, 24, as needed, without being directly connected to the chambers 11, 12, 13.

Although not shown, the apparatus of the present invention is provided with a heat treatment gas and a coolant connection to supply and discharge the gas and the coolant required for the heat treatment. When the heat treatment is not performed, the valves 43 and 44 are closed to prevent the argon gas pressure from lowering.

As shown in FIG. 2, the nanometal powder production apparatus 71 is connected to the rear of the storage chamber 12, and the sintering apparatus 72 is connected to the rear of the molding chamber 13. Hydrogen gas is supplied to the nano-metal powder manufacturing apparatus 71 and the sintering gas is supplied to the sintering apparatus 72 so that piping is connected.

The vacuum pump 50 and the argon-filled gas tank 60 are connected to the photohelical instrument system according to the present invention, and the chambers 11, 12 and 13 are completely replaced with argon (purity: 99.9% or more) gas. . After gas replacement, the two red needles of the photohelical instrument are properly adjusted to the positive pressure, and the valve 44 of the vacuum pump 50 connection pipe is closed to maintain the pressure higher than atmospheric pressure at all times. When the ultrafine metal powder is manufactured, the door of the inlet 32 is opened, brought into the storage chamber 12, and the door is closed. The ultrafine metal powder is then placed in a container.

In the manufacture of metal injection molding raw materials, the prepared powder is mixed with an organic binder in the raw material chamber 11 to prepare raw materials for metal injection molding of granules. At this time, since the vaporized organic binder may contaminate the storage chamber 12 of the side, the door of the passage 22 is closed. The manufactured raw materials are taken out through the exchange box.

The powder produced during molding and sintering is molded and pre-sintered in the molding chamber 13 to make it in a state in which it is not oxidized even in contact with air. The presintered product is taken out through the exchange box.

The following two cases describe the operation process in more detail.

(1) Manufacture of Nano Metal Powders (Feedstock) for Metal Injection Molding

If you need manual work in the clean device, put your hand into the glove of the glove box (41) to work. While the argon gas pressure in the cleaning apparatus is always kept slightly higher than 1 atm, the powder produced in the raw material chamber 11 is introduced into the storage chamber 12 by opening the inlet 32. At this time, the nano-metal powder manufacturing apparatus 71 is maintained in a state that does not enter the outside air to prevent the oxidation of the powder. When argon gas escapes when the inlet 32 is opened and approaches 1 atm, the photohelic gauge device automatically opens the argon inlet valve 43 of the gas tank 60 to continuously charge the argon gas.

When the powder enters the storage chamber 12, the inlet 32 is closed. In the passage 22, the valves 43 and 44 are alternately opened and closed to replace with argon gas in the storage chamber 12. Then open the right door of the passage 22 and transfer the powder onto the passage 22, then close the right door of the passage 22 and open the left door to bring the powder to the raw material chamber 11, where the feedstock is fed. Manufacture.

The argon gas of the raw material chamber 11 is substituted on the passage 21 in the same manner as described above. Thereafter, the right door of the passage 21 is opened, the raw material is placed on the passage 21, the left door is opened, and the raw material is taken out.

(2) In case of manufacturing nano metal powder bulk material

The process of manufacturing the feedstock is the same as described above. The same is true for replacing the passage 23 with the argon gas of the storage chamber 12. Open the left door of passage 23 and transfer powder onto passage 23. The left door of the passage 23 is closed and the right door is opened to bring the powder into the forming chamber 13. The powder is molded in the molding chamber 13 and the sintering apparatus is maintained in an inert atmosphere. The inlet 33 is opened and the molded body is put into the sintering apparatus 72. After pre-sintering the molded body in the sintering apparatus 72, the inlet 33 is opened to bring the sintered body into the molding chamber 13.

In the same manner, the argon gas of the molding chamber 13 is replaced on the passage 24. The left door of the passage 24 is opened to put the sintered body into the passage 24, then the left door is closed and the right door is opened to take out the sintered body.

By using the apparatus of the present invention, ultrafine metal powder (20-50 nm) prepared by a Mechanochemical process could be kept in an unoxidized state.

Figure 3 is a graph showing the comparison of the results of the oxidation analysis by the X-ray diffraction method in the embodiment using the apparatus of the present invention and a comparative example thereof.

The ultrafine W-Cu composite powder raw material for metal injection molding prepared in the air as shown in b of FIG. 3 was oxidized to W as a main component, but was not oxidized to W as manufactured in a clean device as shown in FIG. Cu oxide is formed by oxygen that is decomposed in the organic binder.

Therefore, it is possible to manufacture the ultrafine metal powder product in which oxidative contamination is eliminated with the device of the present invention that is economical compared to the ultrahigh vacuum equipment.

According to the above configuration and operation, it is possible to industrialize due to low cost and low maintenance cost compared to ultra-high vacuum apparatus, and to produce products without oxidation contamination of ultra-fine metal powder without being restricted by ultra-fine metal powder production method. .

It is apparent to those skilled in the art that the present invention is not limited to the described embodiments, and that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, such modifications or variations will have to belong to the claims of the present invention.

Claims (2)

A raw material chamber 11 for use in manufacturing a metal injection molding raw material, having a glove box 41 for manual operation, and having one side wall with a passage 21 leading to the outside; It is used for storing and weighing ultra-fine metal powder, and includes a glove box 41 for manual operation and an inlet 32 for entering and exiting an object, and one side wall is sealingly connected to the other side wall of the raw material chamber 11. A storage chamber 12 having a passage 22 formed therein; It is used for forming and sintering ultra-fine metal powder, and includes a glove box 41 for manual operation and an inlet 33 for entering and exiting an object, and one side wall is sealingly connected to the other side wall of the storage chamber 12. A forming chamber 13 having a passageway 23 formed therein, and the other side wall having a passageway 24 communicating with the outside; A vacuum pump 50 communicating with the raw material chamber 11, the storage chamber 12, and the molding chamber 13 to exhaust the air therein; A gas tank 60 communicating with the raw material chamber 11, the storage chamber 12, and the molding chamber 13 to inject an inert or protective gas therein; A pressure gauge 42 connected to each of the raw material chamber 11, the storage chamber 12, and the molding chamber 13 to detect vacuum and gas pressure inside the chambers 11, 12, 13; And To the connections between the chambers 11, 12, 13 and the vacuum pump 50 and between the chambers 11, 12, 13 and the gas tank 60. And valves 43 and 44 installed to intercept the flow path, Here, the passages 21, 22, 23, 24 have doors openable at both ends, respectively, In addition, the nano-metal powder manufacturing apparatus 71 is hermetically communicated with the inlet 32 of the storage chamber 12, In addition, the sintering device 72 is hermetically connected to the inlet 33 of the molding chamber 13, In addition, the vacuum pump 50, the gas tank 60, the pressure gauge 42 and the valve 43, 44 is through the passages 21, 22, 23, 24 through the raw material chamber 11 ), Ultra-fine metal powder product manufacturing apparatus characterized in that the exhaust chamber or the gas injection is made to the storage chamber (12), the forming chamber (13). delete