KR20150000715A - Powder spray apparatus and coating method, coating structure using the same - Google Patents

Abstract

The powder spraying apparatus according to an embodiment of the present invention includes a vacuum body having a vacuum formed therein and a vacuum body connected to the vacuum body to heat the transfer gas so that the powder is injected into the vacuum body, And the like.
According to another aspect of the present invention, there is provided a coating method using the powder spraying apparatus, comprising the steps of: providing a coating member to the vacuum body; And a coating step of spraying the powder onto the coated member piled on the transfer gas heated by the heating injection unit.
In addition, in the coating structure according to another embodiment of the present invention, the coated member is formed of a metal, a ceramic, or a plastic material, and the powder may be provided as a sintering material of a metal or an organic material.

Description

[0001] The present invention relates to a powder spraying apparatus, a coating method using the powder spraying apparatus,

The present invention relates to a powder spraying apparatus, a coating method using the powder spraying apparatus, and a coating structure. More particularly, the present invention relates to a powder spraying apparatus, .

Particle coating refers to the physical state of PVD (Physical Vapor Deposition), CVD (Chemical Vapor Deposition), which is coated on the atomic or molecular basis, because the particles are in the state of particles and particles of several hundreds of nm to several tens of μm collide with the material at high speed. Vapor Deposition) and is characterized in that the chemical composition of the raw powder is not changed.

Examples of the particle coating method include a thermal spray method and a cold vacuum spray method, and are useful for coating solid powder such as metal, alloy, ceramic, and cermet. In these particle coating methods, temperature and injection speed are very important factors.

In thermal spraying, the thermal spray is heated near the molten state of the powder material and blows a high-pressure gas to the coating material by the combustion gas to collide with the material at a particle velocity of 340 to 1000 m / sec above the sonic velocity .

Cold spray is applied at a low temperature in comparison with thermal spraying method, and the transfer gas is heated together with the powder, but the powder does not reach the molten state, and the inside of the body having the coated member is not vacuum, And a spraying unit is sprayed at a high pressure to realize a high speed powder spraying speed by a pressure difference, whereby powder particles are plastically deformed and coated on a workpiece.

However, in the case of the thermal spraying method or the cold spraying method, the body to which the coated member is provided is at normal pressure. Since the high-pressure gas of a few MPa class is used for the powder conveying gas in order to increase the pressure difference with the normal pressure, There are many disadvantages.

Further, in order to realize a particle velocity for high-speed collision under the atmospheric pressure condition of the coated member, there is a problem that only expensive gases such as He and N ₂ should be used.

In other words, such a spraying method is generally used for coating a small area, and a particle size of several tens of micrometers is required for high-speed injection due to the air resistance problem at an atmospheric pressure condition, and due to problems such as coating layer defects and residual stress, It is necessary to form a thick film coating of several hundreds of micrometers thick, and a dense thin film coating of several micrometers is a real problem.

On the other hand, in the room temperature vacuum spraying method, in order to realize the pressure difference, a method of maintaining the pressure of the coating part at a low pressure (vacuum) is adopted unlike the spraying method. That is, as shown in FIG. 1, a coated member is provided inside the vacuum body, and the powder of the powder supplying part 210 'is coated on the transporting gas of the gas supplying part 220' do.

Such a room-temperature vacuum spraying method is advantageous in that the gas consumption is very small compared with the spraying method because the pressure of the transfer gas does not need to be high, and a dense thin film coating of a large area and several μm is possible.

However, since the spraying speed of the powder particles is slow compared to the spraying method, there is a limit to the coating material, and it is generally used for coating a brittle material such as ceramics.

Therefore, it is necessary to study the powder spraying apparatus, the coating method and the coating structure to solve the problems of the spraying method and the room temperature vacuum spraying method.

An object of the present invention is to provide a powder spraying device capable of spraying at a high pressure regardless of the size or kind of powder, a consumption amount of gas for high-pressure spraying is relatively small, .

The powder injector according to an embodiment of the present invention includes a vacuum body having a vacuum formed therein and a vacuum body connected to the vacuum body to heat the transfer gas so that the powder is injected into the vacuum body while being piled up with the flow of the transfer gas And the like.

The heating spray unit of the powder spraying apparatus according to an embodiment of the present invention is connected to the vacuum body and includes a powder supply part for supplying powder, a gas supply part connected to the vacuum body, And a gas heating unit provided in the gas supply unit to heat the supply unit.

The heating spray unit of the powder spraying apparatus according to an embodiment of the present invention may further include a powder heating unit provided in the powder supply unit to heat the powder supply unit.

In addition, the powder heating unit of the powder spraying apparatus according to an embodiment of the present invention may heat the powder to a glass transition temperature or a softening point or more.

The heating spray unit of the powder spraying apparatus according to an embodiment of the present invention is connected to the powder supply unit and the gas supply unit such that the powder is injected in a slanting manner with the transfer gas heated by the heating unit, And a nozzle unit provided in the vacuum body.

In the nozzle unit of the powder spraying apparatus according to an embodiment of the present invention, a plurality of gas transfer pipes of the gas supply unit are coupled to a peripheral portion of the nozzle unit, and a powder transfer pipe of the powder supply unit is coupled to a central portion of the nozzle unit , And may be extended longer than the gas transfer pipe to the inside of the nozzle portion.

Further, the vacuum body of the powder spraying apparatus according to an embodiment of the present invention may include a cooling part provided in the chamber part to maintain the chamber part and the inside thereof at a low temperature state.

Further, the cooling section of the powder spraying apparatus according to an embodiment of the present invention may be provided in a double structure so as to surround the outer surface of the chamber section so as to be cooled at the front surface of the chamber section.

Further, the cooling part of the powder spraying device according to an embodiment of the present invention may be provided inside the chamber part with a cooling coil or a cooling fin.

According to another aspect of the present invention, there is provided a coating method using the powder spraying apparatus, comprising the steps of: providing a coating member to the vacuum body; And a coating step of spraying the powder onto the coated member piled on the transfer gas heated by the heating injection unit.

In addition, in the coating structure according to another embodiment of the present invention, the coated member is formed of a metal, a ceramic, or a plastic material, and the powder may be provided as a sintering material of a metal or an organic material.

The powder spraying apparatus of the present invention, and the coating method and coating structure using the powder spraying apparatus of the present invention are advantageous in that they can be formed into high-pressure gas and sprayed without increasing consumption of gas by heating and supplying the transfer gas.

Since the high-pressure injection can be performed without increasing the gas consumption amount as described above, there is an advantage that the dense coating can be performed in a large area without being restricted to the density, size, kind, etc. of the powder to be injected.

In addition, since the inside of the vacuum body is also cooled, the pressure difference with the conveyance gas can be increased, and the pressure inside the vacuum body can be prevented from rising during the injection of the conveyance gas, There is an effect that it can be maintained to be sprayed.

In addition, the powder to be sprayed is also heated and provided, thereby further increasing the coating rate of the powder by plastic deformation.

1 shows a conventional coating apparatus by a room-temperature vacuum spraying method.
2 is a configuration diagram showing a first embodiment of the powder spraying apparatus of the present invention.
3 is a configuration diagram showing a second embodiment of the powder spraying apparatus of the present invention.
4 is a view showing that a coating layer is formed by plastic deformation of a powder.
5 is a cross-sectional view showing a nozzle unit in the powder spraying apparatus of the present invention.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventive concept. Other embodiments falling within the scope of the inventive concept may readily be suggested, but are also considered to be within the scope of the present invention.

The same reference numerals are used to designate the same components in the same reference numerals in the drawings of the embodiments.

The powder spraying apparatus of the present invention and the coating method using the powder spraying apparatus according to the present invention are used for heating and spraying a conveying gas provided for spraying the powders (2) while spraying the powders (2), and a vacuum body The invention relates to cooling.

According to this, it is possible to form and discharge the gas at a high pressure without increasing the consumption amount of the gas, so that the dense coating can be performed in a large area without being restricted to the density, size, kind and the like of the powder 2 to be sprayed.

In addition, by cooling the inside of the vacuum body 100, the pressure difference with respect to the conveyance gas can be increased, and the pressure inside the vacuum body 100 can be increased during the injection of the conveyance gas So that the powder 2 can be stably sprayed.

2 is a configuration diagram showing the first embodiment of the powder spraying apparatus 1 of the present invention, and Fig. 3 is a configuration diagram showing a second embodiment of the powder spraying apparatus 1 of the present invention .

2 and 3, a powder spraying apparatus 1 according to an embodiment of the present invention includes a vacuum body 100 having a vacuum formed therein and a powder body 2 connected to the vacuum body 100, And a heating injection unit 200 for heating and supplying the transfer gas so as to be injected into the vacuum body 100 on the basis of the flow of the transfer gas.

The heating injection unit 200 of the powder injecting apparatus 1 according to an embodiment of the present invention is connected to the vacuum body 100 and includes a powder supply unit 210 for supplying the powder 2, A gas supply unit 220 connected to the body 100 to supply a transfer gas and a gas heating unit 230 provided in the gas supply unit 220 to heat the gas supply unit 220.

The heating injection unit 200 of the powder injection apparatus 1 according to an embodiment of the present invention may further include a powder heating unit 240 provided in the powder supply unit 210 to heat the powder supply unit 210, As shown in FIG.

That is, the powder spraying apparatus 1 according to the present invention improves the high-speed spraying by forming the high-pressure gas by increasing the consumption amount of the gas beforehand by heating and supplying the sprayed gas and powder 2 before spraying It is possible to spray the powder 2 at a high speed by forming a high-pressure gas without increasing the consumption amount of the gas.

The vacuum body 100 may serve to provide a coating member 3 provided for coating. That is, the coating member 3 may be mounted on the vacuum body 100, and the coating member 3 may be mounted on the transfer member 3a to be coated in a predetermined direction So that the coating area can be widened.

The vacuum body 100 may include a chamber part 110 provided with the coated member 3 to form a vacuum and a vacuum 130 provided in the chamber part 110 .

The chamber 110 may be provided to be hermetically closed to maintain vacuum formation by the vacuum 130. The member transfer device 3a to which the coated member 3 is provided may be provided inside the chamber part 110. [

The vacuum chamber 130 may include a vacuum pump 131, a powder filter 132, and a cooler 133. The vacuum pump 131 may be a vacuum pump, And the like can be provided to the chamber part 110. That is, the vacuum chamber 130 can maintain the chamber 110 at a low vacuum of 0.01 to 10 Torr.

The vacuum pump 131 serves to provide a driving force for exhausting the air inside the vacuum chamber 130. The powder filter 132 is provided in the powder 2 sprayed from the heating injection unit 200, It is possible to prevent the vacuum pump 131 from malfunctioning by filtering the remaining powder 2 without being coated.

In addition, the cooler 133 serves to cool the powder 2 before contacting the powder filter 132 because the powder 2 can be provided at a high temperature.

That is, when the inside of the chamber 110 is sucked in by the vacuum cleaner 130 in order to form a vacuum inside the chamber 110, the vacuum is first cooled by the cooler 133, The suspended solids are filtered by the powder filter 132 and finally the air is discharged to the outside by the vacuum pump 131 so that the inside of the chamber 110 can be formed into a vacuum environment.

Meanwhile, the vacuum body 100 may further include a cooling unit 120 so that the temperature difference between the vacuum body 100 and the heating injection unit 200 will be further increased so that the vacuum body 100 can be ejected at a high speed by a larger pressure difference.

That is, the cooling unit 120 may be provided separately from the cooler 133 to maintain the temperature of the entire chamber 110 at a low temperature.

As a result, the powder 2 can be injected at a higher speed by increasing the pressure difference between the inside of the chamber 110 and the transfer gas, and at the same time, the transfer gas and the powder 2 The pressure inside the chamber 110 is prevented from rising and the powder 2 can be stably sprayed.

That is, the vacuum body 100 of the powder injection apparatus 1 according to an embodiment of the present invention includes a chamber 110 and a cooling unit (not shown) provided in the chamber unit 110 The cooling unit 120 may include a cooling unit 120 and a cooling unit 120. The cooling unit 120 may be provided in a double structure so as to surround the outer surface of the chamber unit 110 so as to be cooled on the front surface of the chamber unit 110, Or may be provided as a second embodiment provided inside the chamber part 110 with cooling fins.

When the cooling unit 120 is provided in a double structure, as shown in FIG. 2, since the cooling unit 120 can be provided in a double chamber structure outside the chamber unit 110, It is possible to cool the entire surface of the chamber 110, thereby speeding up the cooling rate and speeding up the temperature control inside the chamber 110.

To this end, the refrigerant is supplied to one end of the cooling part 120 having a double structure to cool it, and the refrigerant is discharged to the other end, so that the cooling can be performed by circulating the refrigerant.

3, when the cooling part 120 is provided inside the chamber part 110 with a cooling coil or a cooling fin, the cooling part 120 can be cooled directly in the chamber part 110, The cooling area can be widened, and the cooling efficiency can be increased.

The heating injection unit 200 may heat the transfer gas or the powder 2 and inject the high-speed injection gas into the vacuum body 100. Thus, the powder 2 can be coated on the coated member 3 provided in the vacuum body 100 by plastic deformation.

The heating injection unit 200 may include a powder supply unit 210, a gas supply unit 220, a gas heating unit 230, a powder heating unit 240, a nozzle unit 250, and the like. The nozzle unit 250 will be described later in detail with reference to FIG.

The powder supply unit 210 may provide a powder 2 to be coated on the coated member 3 and may be heated and supplied by a powder heating unit 240 to be described later.

The powder feeder 210 may provide a powder feed pipe 211 connected to the powder chamber to be connected to the vacuum body 100 and the powder feed pipe 211 may be connected to the powder heating unit 240 Or may be provided in a coil shape to enhance the heat absorption rate to be provided.

The powder supply unit 210 may adjust the supply amount of the powder 2 and may use a part of the transfer gas from the gas supply unit 220 as a driving force for initial transfer of the powder 2 have.

That is, a part of the transfer gas may be supplied from the connection pipe 223a connected to the gas distributor 223 of the gas supply unit 220, which will be described later, and may be used as energy for initial operation of floating or transferring the powder 2 And the pressure of the powder supply unit 210 may be controlled to 600 to 800 Torr.

Meanwhile, the powder 2 is not limited to a firing material which can be coated even at a relatively low jetting speed such as copper (Cu), nickel (Ni), etc., and can be provided as a high strength alloy as well as an Fe-based metal.

The gas supply unit 220 may supply a transfer gas for spraying the powder 2 at high speed. That is, when the powder (2) is injected into the vacuum body (100), when the transfer gas is injected, the powder is ejected by being piled on the transfer gas. Therefore, when the transfer gas is injected at high speed, The powder 2 can be injected at a high speed.

Examples of the transfer gas include nitrogen (N2), helium (He), and argon (Ar). However, dry air is preferable in consideration of the amount and price.

In addition, the gas supply unit 220 can be maintained at a high pressure state in order to inject the transfer gas at a high speed. In addition, a gas to be described later can be heated by the heating unit 230 to provide a high- do.

For this, the gas supply unit may include a gas storage chamber 221, a gas transfer pipe 222, a gas distributor 223, a dehumidifier 224, and the like.

The gas storage chamber 221 may be provided as a sealed reservoir for maintaining a high pressure gas and may be provided to control the pressure and the gas transfer pipe 222 may be connected to the gas distributor 223, And may be connected to the gas storage chamber 221 and the vacuum body 100 via the gas storage chamber 221 and the vacuum chamber 100.

Meanwhile, the gas transfer pipe 222 may be provided in a coil shape in order to increase the heat absorption rate provided by the heating unit 230, which will be described later.

The gas distributor 223 may be used as an initial driving force for moving the powder 2 in the powder supply unit 210 by supplying a part of the transfer gas to the powder supply unit 210.

In addition, the dehumidifier 224 serves to prevent the powder 2 from being deteriorated at the time of spraying the transfer gas by removing moisture inside the transfer gas.

The gas heating unit 230 may be provided in the gas supply unit 220 to heat the transfer gas. That is, in order to provide the transfer gas at a high pressure, the conventional method of increasing the input amount of the transfer gas is disadvantageous in that it consumes a large amount of consumed gas. In order to solve this problem, It is suggested.

That is, the gas heating unit 230 can increase the volume of the transport gas by heating the transport gas to provide the gas as a high-pressure gas. This can be seen from the result that the pressure increases when the temperature is raised in the ideal gas equation (Pv = RT, P is pressure, v is volume, R is constant, T is temperature).

As described above, the present invention provides the gas to further include the heating part 230 for the purpose of increasing the pressure by heating the transfer gas. That is, the gas is designed and constructed for the purpose of merely having the heating part 230, and the effect therefor has been described above.

Meanwhile, the gas heating unit 230 may be provided with a sensor S for measuring the temperature, and may be connected to the control unit C so that the gas can control the heating temperature by the heating unit 230.

Also, it is advantageous that the gas evolving portion 230 is provided to the gas conveying pipe 222 through which the gas moves, among the gas supplying portion 220. That is, since the gas transfer pipe 222 is provided in the form of a coil so that the gas can spread the contact area with the heat part 230, the gas heat transfer part 230 is provided to the gas transfer pipe 222 .

The powder heating unit 240 may be provided in the powder supply unit 210 to heat the powder 2. [ The heating of the powder 2 is intended to facilitate the plastic deformation of the powder 2, and a detailed description thereof will be described later with reference to FIG.

The powder heating unit 240 may be provided with a powder feed pipe 211 that can be provided in a coil shape of the powder feed unit 210 that can increase the contact area so as to increase the heating efficiency of the powder 2. [ Or the like.

Also, the powder heating unit 240 may be provided with a sensor S for temperature measurement, and may be connected to the control unit C to control the heating temperature.

FIG. 4 is a view showing that a coating layer is formed by plastic deformation of the powder 2. Referring to FIG. 4, the powder heating unit 240 of the powder spraying apparatus 1 according to an embodiment of the present invention, (2) can be heated to the glass transition temperature or above the softening point.

That is, by heating the powder 2 at a temperature higher than the glass transition temperature or the softening point, the powder heating unit 240 can maintain the powder 2 in an easily plastic deformation state.

4, when the powder 2 impinges on the coated member 3, the powder 2 is plastically deformed to deposit a layer on the coated member 3, The powder heating unit 240 is heated to a temperature not lower than the glass transition temperature or the softening point which facilitates the plastic deformation so that the powder 2 is easily stacked on the coated member 3. [ .

5 is a cross-sectional view illustrating a nozzle unit 250 in the powder spraying apparatus 1 of the present invention. Referring to FIG. 5, the heating spray unit 200 of the powder spraying apparatus 1 according to an embodiment of the present invention, Is connected to the powder supply part (210) and the gas supply part (220) so that the powder (2) is sprayed on the transfer gas heated by the heating part (230) And a nozzle unit 250 provided in the nozzle unit 250.

The nozzle unit 250 of the powder spraying apparatus 1 according to the embodiment of the present invention is configured such that the gas transfer pipe 222 of the gas supply unit 220 is connected to the peripheral portion 252 of the nozzle unit 250 A powder conveying pipe 211 of the powder supplying unit 210 is coupled to a central portion 251 of the nozzle unit 250 and is connected to the inside of the nozzle unit 250 As shown in Fig.

That is, it is possible to supply the conveying gas and the powder 2 with the vacuum body 100 through the nozzle unit 250. At this time, the powder 2 is ejected at high speed It can be.

Meanwhile, it is preferable that the distance between the nozzle and the coated member 3 is 10 to 20 mm. If the distance is shorter than 10 mm, the speed of accelerating the powder 2 in the vacuum state is shortened to shorten the speed of the powder 2, and if it is longer than 20 mm, the flow field of the transfer gas is reduced by friction, I do not.

In addition, the nozzle unit 250 can connect the powder transfer pipe 211 to the gas transfer pipe 222 in the injection direction longer than the gas transfer pipe 222, which is provided in the powder transfer pipe 211 And is injected into the vacuum body 100 by being transferred to the transfer gas supplied from the gas transfer pipe 222 as soon as the powder 2 is discharged.

In other words, when the transport gas is injected first to form a flow field, the powder 2 is provided to the nozzle unit 250 and can be easily ejected onto the transport gas.

A coating method according to another embodiment of the present invention is a coating method using the powder spraying apparatus 1, comprising the steps of: providing a coating member 3 to the vacuum body 100; A coating step of spraying the powder (2) onto the coated member (3) while being piled on the transfer gas heated by the heating injection unit (200) so as to be laminated on the coated member (3) .

That is, a coating method using the powder spraying apparatus 1 according to an embodiment of the present invention is shown. In the case of using the powder spraying apparatus 1 in such a coating method, the powder spraying apparatus 1 And serves as a coating apparatus.

The preparing step is a step of providing a coated member 3 to be coated on the inside of the vacuum body 100, thereby mounting the coated member 3 on the member feeder 3a.

In the coating step, the gas heating unit 230 heats the transfer gas supplied from the gas supply unit 220, and the powder 2 supplied from the powder supply unit 210 is heated by the powder heating unit 240 The heated transfer gas and the powder 2 are supplied to the nozzle unit 250 and sprayed to the vacuum body 100 at a high speed so that the coated member 3 ), And the coating layer can be formed.

That is, in the coating step, the conveying gas is heated without further feeding of the conveying gas to provide a high-pressure conveying gas, and the powder 2 is easily heated by plastic deformation to facilitate the formation of the coating layer .

In the coating structure according to another embodiment of the present invention, the coated member 3 is formed of a metal, a ceramic, or a plastic material, and the powder 2 may be provided as a sintering material of a metal or an organic material.

That is, the to-be-coated member 3 is Al, Cu, Ti, W, Ta, Zn, Mg, Ni, Cr, Fe metal, TiN, AlN, CrN, of Al ₄ C _3, B ₄ C, WC, Ceramic materials such as Al ₂ O ₃ , Zr ₂ O ₃ and Ti ₂ O ₃ , or plastic materials such as polystyrene, polypropylene, polyethylene, epoxy, nylon and Teflon.

The powder 2 may be provided not only as a metal powder such as Cu and Ni but also as an Fe-based metal, a high-strength alloy, etc. In the case of an organic material, any compound containing at least carbon, hydrogen and oxygen do.

Example 1

In the present embodiment, the application of the powder spraying apparatus 1 improves the spraying speed of the powder 2 and enlarges the usable particle size range.

Cold rolled steel was used as the material and Cu powder (2) was used as the coating material. The average particle size (D50) of the Cu powder (2) is 8 占 퐉 and the particle size has a normal distribution in the range of 1 to 15 占 퐉.

Under the coating conditions, the pressure of the initial vacuum body 100 was set to 5 x 0.01 Torr and the pressure of the powder feeder 210 was set to 700 Torr, and the Cu powder 2 was placed in the powder feeder 210 to perform a coating experiment . The flow rate of the gas was set at 10 L / min for the powder feed pipe 211 and 30 L / min for the gas feed pipe 222, and the nozzle unit 250 had a slit size of 0.7 mm × 20 mm by using a nozzle having a nozzle unit 250 fixed at a distance of 10 mm from the coating material while moving the material twice at a rate of 5 mm / sec.

The powder heating unit 240 is operated only to operate the gas heating unit 230 so that the transport gas temperature is changed to room temperature, 100 ° C., 300 ° C., and 600 ° C., The flow rate of the cooling water was adjusted so that the pressure of the cooling water 100 was 5 Torr or less. The thickness of the end face coating layer was measured using a scanning electron microscope (SEM) on the coated member 3, and the results are shown in Table 1 together with the coating conditions.

division Flow rate (L / min) Powder temperature
(° C) Gas temperature
(° C) Vacuum body
Pressure (Torr) Cu coating thickness
(μm) Powder transfer
pipe Gas transfer
pipe Comparative Example 1 10 30 Room temperature Room temperature 2.6 0.7 Inventory 1 10 30 Room temperature 100 3.1 1.1 Inventory 2 10 30 Room temperature 300 4.5 3.8 Inventory 3 10 30 Room temperature 600 4.7 5.3

It can be seen that as the transport gas temperature is increased, the thickness of the coating layer increases. This result is attributed to the fact that as the temperature of the transfer gas increases, the transfer gas becomes high in pressure and the injection speed of the powder 2 increases as the pressure difference between the high-pressure transfer gas and the internal pressure of the vacuum body 100 increases .

That is, only the Cu powder (2) having a small size is coated under the normal temperature condition of the comparative example 1, so that the thickness of the coating layer is thin, but the coatable particle size is increased by applying the high- will be.

Example 2

In this embodiment, the effect of heating the powder 2 in the powder spraying apparatus 1 will be described.

The other coating conditions were the same as in Example 1, and the powder heating unit 240 and the gas heating unit 230 were operated to perform the coating experiment by the temperature and the gas temperature of the powder 2 shown in Table 2. The thickness of the end face coating layer was measured using a scanning electron microscope (SEM) on the coated member 3, and the results are shown in Table 1 together with the coating conditions.

division Flow rate (L / min) Powder temperature
(° C) Gas temperature
(° C) Vacuum body
Pressure (Torr) Cu coating thickness
(μm) Powder transfer
pipe Gas transfer
pipe Honorable 4 10 30 300 100 3.0 1.7 Inventory 5 10 30 300 300 4.7 4.2 Inventory 6 10 30 500 300 4.8 6.8 Honorable 7 10 30 500 600 5.3 9.7

The coating thickness did not greatly increase as compared with the normal temperature condition (Inventive Example 2) at the temperature of the powder (2) of 300 ° C (Example 5), but at the temperature of 500 ° C of the powder (2) It can be seen that the coating thickness is increased by about two times as compared with the conditions (Inventive Example 2, Inventive Example 3).

It can be seen that the efficiency of the lamination is greatly increased by heating the powder 2 near the glass transition temperature to the softening point, and it is found that the effect is further increased by mixing with the conveying gas of high temperature and high pressure.

The reason why the coating thickness of the inventive example 4 is increased to some extent is that the increase in the flow rate is not large as compared with the case in which the gas transportation pipe 222 is heated because the flow rate of the gas is heated while the powder 2 is heated .

From the result that the coating thickness of the inventive example 4 is smaller than that of the inventive example 2, it can be seen that the high-pressure conveying gas effect of the example 1 is not due to the increase of the powder 2 temperature.

That is, although the temperature of the powder 2 may be increased in the process of mixing the high-temperature and high-pressure transport gas formed by heating the gas transfer pipe 222 with the powder transfer pipe 211, The main reason for the increase in the thickness of the coating layer as the temperature of the transfer gas increases in Example 1 is the increase in the speed of the powder 2 due to the formation of the transfer gas at high pressure.

As a result of measuring the coating density from the SEM image of the coating film in the above example of the invention, it was confirmed that a very dense coating film of 99 vol% or more was formed in all the test pieces.

1: Powder Injection Apparatus 2: Powder
3: Coated member 100: Vacuum body
110: chamber part 120: cooling part
130: Vacuum pump 131: Vacuum pump
132: Powder filter 133: Cooler
200: heating spray unit 210: powder supply unit
211: powder transfer pipe 220: gas supply part
221: gas storage chamber 222: gas transfer pipe
223: Gas distributor 224: Dehumidifier
230: gas heating part 240: powder heating part
250: nozzle part 251:
252:

Claims (11)

A vacuum body having a vacuum formed therein; And
A heating injection unit connected to the vacuum body and heating and supplying the transfer gas so that the powder is injected into the vacuum body in a flow of the transfer gas;
And the powder spraying device. The method according to claim 1,
The heating injection unit includes:
A powder supply unit connected to the vacuum body and supplying powder;
A gas supply unit connected to the vacuum body and supplying a transfer gas; And
A gas heating unit provided in the gas supply unit to heat the gas supply unit;
And the powder spraying device. 3. The method of claim 2,
The heating injection unit includes:
A powder heating unit provided in the powder supply unit to heat the powder supply unit;
Further comprising: The method of claim 3,
Wherein the powder heating unit heats the powder to a glass transition temperature or a softening point or higher. 3. The method of claim 2,
The heating injection unit includes:
A nozzle connected to the powder supply part and the gas supply part and provided to the vacuum body so that the powder is injected in a slant manner with the transfer gas heated by the heating part;
Further comprising: 6. The method of claim 5,
In the nozzle unit,
A plurality of gas transfer pipes of the gas supply unit are coupled to a peripheral portion of the nozzle unit,
Wherein the powder conveying pipe of the powder supplying unit is coupled to a central portion of the nozzle unit and extends longer than the gas conveying pipe to the inside of the nozzle unit. The method according to claim 1,
Wherein the vacuum body comprises:
A chamber portion; And
A cooling part provided in the chamber part so as to keep the inside at a low temperature state;
And the powder spraying device. 8. The method of claim 7,
Wherein the cooling portion is provided in a double structure so as to surround the outer surface of the chamber portion so as to be cooled at the front surface of the chamber portion. 8. The method of claim 7,
Wherein the cooling portion is provided inside the chamber portion with a cooling coil or a cooling fin. A coating method using the powder spraying apparatus according to any one of claims 1 to 9,
Providing a coating member to the vacuum body; And
A coating step of spraying the powder onto the coated member piled on the transfer gas heated by the heating injection unit so that the powder is plastically deformed and laminated on the coated member;
≪ / RTI > A coating structure formed by the coating method of claim 10,
The coated member may be formed of a metal, a ceramic, or a plastic material,
Wherein the powder is provided as a sintering material of a metal or an organic material.

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