KR101986306B1 - Vacuum suspension plasma spray aparattus and vacuum suspension plasma spray method - Google Patents

Abstract

The present invention relates to a vacuum suspension plasma spraying apparatus and a vacuum suspension plasma spraying method, and a vacuum suspension plasma spraying apparatus according to an embodiment of the present invention includes a vacuum chamber; A pressure regulating device for maintaining the pressure inside the vacuum chamber at 10 to 500 mbar; A plasma gun disposed in the vacuum chamber, the plasma gun including a plasma generating unit generating a plasma and an ejection port ejecting the generated plasma; A drip free atomizing nozzle arranged to supply a suspension to the plasma ejected from the plasma gun; And a suspension supply part communicating with the drip free atomizing nozzle and supplying suspension to the drip free atomizing nozzle, wherein the suspension is a mixture of a powder and a solvent, and the powder is a metal powder, an oxide based ceramic powder, And a non-oxide ceramic powder, wherein the solvent comprises at least one of water, alcohol, benzene, or toluene.

Description

TECHNICAL FIELD [0001] The present invention relates to a vacuum suspension plasma spraying apparatus and a vacuum suspension plasma spraying method,

The present invention relates to a vacuum suspension plasma spraying apparatus and a vacuum suspension plasma spraying method.

Ceramics refers to materials made by combining metallic elements with non-metallic elements and is largely classified into oxide ceramics and non-oxide ceramics. Ceramics is characterized by its excellent mechanical properties (strength, hardness, etc.), high heat resistance properties (high temperature stability and insulation), unique electronic properties (dielectric, insulating, semiconducting and piezoelectric), magnetic properties (ferromagnetic and paramagnetic) (Light transmittance, light absorption, etc.) and chemical properties (corrosion resistance, etc.), which are indispensable materials for the development of modern civilization. Ceramics have a disadvantage that they are more fragile and difficult to mold than metal or polymer materials. In order to overcome these disadvantages, techniques for coating ceramics with various means have been actively developed.

There are various kinds of coating methods such as PVD, CVD, aerosol deposition, and plasma spraying. PVD or CVD is a method of coating ceramics such as DLC, TiN, CrN, and ZrO2 on a surface of a cutting tool or a part frequently abraded, and has an advantage of controlling the composition and crystallinity of the coating. In addition to abrasion resistant parts, it can be applied to various coatings such as semiconductors, solar cell display coatings and optical coatings depending on the application range. Typically, the coating thickness is in the range of 2-5 mu m called thin film, although a thicker coating is also possible, which requires a considerable amount of time and a special process.

The aerosol deposition method (KR 10-0818188) is a method of spraying a fine ceramic powder onto a substrate to form a coating on the substrate, which can form a dense, crack-free coating capable of high-speed coating of about 180 μm per minute There is a problem that the kind of powder that can be coated is limited and the thickness of the coating is limited to a few micrometers as in the above case.

Plasma spraying is a technique for instantly melting a powdery material using a high-temperature and high-speed plasma flame and colliding with the substrate at high speed to form a rapidly solidified coating. With this method, a wide range of materials such as metals, ceramics and intermetallic compounds can be coated at a high speed up to several mm thick. As described above, the spraying method requires spraying powder having a small size for dense / uniform coating and rapid coating due to the characteristic of the process of injecting the powdery material into the high energy flame from the outside and melting and accelerating the powder. However, as the size of the powder becomes smaller, the fluidity is lowered, such as aggregation or aggregation, in the transferring process of the powder, and uniform coating is not achieved.

Korean Patent Publication No. 10-0818188

Disclosure of Invention Technical Problem [8] The present invention has been made in view of the above problems, and it is an object of the present invention to provide a method of spray coating a suspension containing fine powder, The present invention provides a vacuum suspension plasma spraying method which solves the problem of energy degradation and oxidation and forms a dense and thick coating in a short time.

A vacuum suspension plasma spraying apparatus according to an embodiment of the present invention includes a vacuum chamber; A pressure regulating device for maintaining the pressure inside the vacuum chamber at 10 to 500 mbar; A plasma gun disposed in the vacuum chamber, the plasma gun including a plasma generating unit generating a plasma and an ejection port ejecting the generated plasma; A drip free atomizing nozzle arranged to supply a suspension to the plasma ejected from the plasma gun; And a suspension supply part communicating with the drip free atomizing nozzle and supplying suspension to the drip free atomizing nozzle, wherein the suspension is a mixture of a powder and a solvent, and the powder is a metal powder, an oxide based ceramic powder, And a non-oxide ceramic powder, wherein the solvent comprises at least one of water, alcohol, benzene, or toluene.

The drip free atomizing nozzle may include a suspension supply pipe, a gas supply pipe, a suspension blocking unit for blocking supply of suspension from the suspension supply pipe, a suspension supplied from the suspension supply pipe, and a gas supplied from the gas supply pipe Wherein the suspension blocking portion is in an open state such that a suspension flows from the suspension supply pipe to the discharge port when gas is supplied from the gas supply pipe and when the gas is not supplied from the gas supply pipe And may be in an off-state such that the suspension from the suspension supply pipe to the discharge port is blocked.

The diameter of the suspension outlet of the dripping atomizing nozzle may be 100 to 1000 탆.

Also, the suspension supply flow rate of the suspension supply unit may be 1 g / min to 2000 g / min.

The suspension supply unit may further include a flow rate adjusting device for adjusting a suspension flow rate and a flow rate measuring device for measuring a suspension flow rate.

The drip free atomizing nozzle may further include a blocking member for blocking the vacuum chamber and the suspension supply unit when the suspension is not supplied from the suspension supply unit.

A vacuum suspension plasma spraying method according to an embodiment of the present invention is a method of forming a coating layer using a vacuum suspension plasma spraying apparatus, comprising: preparing a suspension and a substrate; And disposing the substrate in a vacuum chamber; And forming a coating layer on the substrate, wherein the suspension is a mixture of a powder and a solvent, and the powder is a mixture of a metal powder, an oxide-based ceramic powder and a non-oxide-based ceramic powder Wherein the solvent comprises at least one of water, alcohol, benzene, or toluene, and wherein the vacuum suspension plasma spray apparatus includes a drip free atomizing nozzle arranged to supply a suspension.

The diameter of the powder may be 10 to 1000 nm.

The present invention provides a suspension in which a suspension of nanometer-sized metal, oxide-based ceramic or non-oxide ceramic powder dispersed in a solvent is supplied into a vacuum plasma spraying chamber having a pressure lower than atmospheric pressure, There is an advantage in that a dense and thick coating can be formed in a short time under a vacuum or an inert atmosphere through decomposition of the suspension, heating and melting of the solid particles by the plasma flame, and acceleration of the supplied suspension.

The vacuum suspension plasma spraying method according to the present invention does not need to granulate the fine powder because the sprayed plasma spraying method transfers the fine particles of sprayed powder having a size of less than 1 탆, There is an advantage that the formation of a nonuniform coating due to unstable melting can be suppressed and a fine and dense coating can be formed. In addition, since the conventional vacuum plasma spraying apparatus is used as it is, the fine powder of nanometer size is directly injected into the plasma flame under a vacuum or an inert atmosphere to melt and accelerate the collision and lamination with the substrate, Which is advantageous in that a high-quality dense coating can be economically achieved.

1 is a structural view of a vacuum suspension plasma spraying apparatus according to an embodiment of the present invention.
2 is a side cross-sectional view of a drip free atomizing nozzle of a vacuum suspension plasma spraying apparatus according to an embodiment of the present invention.
3 shows a suspension supplied by a plasma sprayed in a vacuum suspension plasma spraying apparatus and a drip free atomizing nozzle according to an embodiment of the present invention.
4 shows a flow diagram of a vacuum suspension plasma spraying method according to an embodiment of the present invention.
5 is a photograph of a vacuum suspension plasma spray coating surface and side cross-section formed by Example 1. Fig.
6 is a photograph of the surface of the vacuum suspension plasma spray coating formed by Example 2 and the side cross-section thereof.
7 is a photograph of a vacuum suspension plasma spray coating surface and side cross-section formed by Example 3. Fig.
8 is a photograph of a vacuum suspension plasma spray coating surface and side cross-section formed according to Example 4. Fig.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Further, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings may be exaggerated for clarity of description, and the elements denoted by the same reference numerals in the drawings are the same elements. In the drawings, like reference numerals are used throughout the drawings. In addition, "including" an element throughout the specification does not exclude other elements unless specifically stated to the contrary.

Vacuum Suspension plasma  Spraying device

1 is a structural view of a vacuum suspension plasma spraying apparatus according to an embodiment of the present invention.

Referring to FIG. 1, a vacuum suspension plasma spraying apparatus 1000 according to an embodiment of the present invention includes a vacuum chamber 1100; A pressure regulator 1200 for maintaining the pressure inside the vacuum chamber 1100 at 10 to 500 mbar; A plasma gun (1300) disposed in the vacuum chamber (1100), the plasma gun (1300) including a plasma generating unit generating plasma and a jetting port for jetting the generated plasma; A drip free atomization nozzle 1400 arranged to supply a suspension to the plasma ejected from the plasma gun 1300; And a suspension supply unit 1500 communicating with the drip free atomization nozzle 1400 and supplying suspension to the drip free atomization nozzle 1400.

The suspension is a mixture of powder and solvent, and the powder includes at least one of metal powder, oxide ceramic powder and non-oxide ceramic powder, and the solvent includes at least one of water, alcohol, benzene, or toluene .

The vacuum chamber is a space for performing vacuum suspension plasma spraying, and the inner atmosphere can be controlled to a pressure of 10 to 500 mbar. In addition, the vacuum chamber may be controlled to an atmosphere containing at least one of argon, helium or nitrogen, which is an inert atmosphere, in order to minimize the effect of the atmosphere when the vacuum suspension plasma spraying is performed.

If the pressure inside the vacuum chamber is less than 10 mbar, a large amount of energy may be required to maintain the atmosphere in the plasma chamber. If the pressure inside the vacuum chamber exceeds 500 mbar, the uniformity of the coating layer may deteriorate due to the small size of the plasma flame. .

The diameter of the powder may be 10 to 1000 nm.

When the diameter of the powder is 10 nm or less, there is a problem that the kinetic energy of the particles is low and it is difficult to produce a powder having a size of 10 nm. Also, when the diameter of the powder is more than 1000 nm, the powder may not form a dense thin film.

The plasma gun may be disposed in the vacuum chamber, and may include a plasma generating unit for generating plasma and a plasma ejecting opening for ejecting the generated plasma. The plasma generator includes a cathode and an anode for generating a plasma, and a mainstream gas generating a plasma may be injected into the plasma generator.

2 is a side cross-sectional view of a drip free atomizing nozzle of a vacuum suspension plasma spraying apparatus according to an embodiment of the present invention.

2, the drip free atomizing nozzle 1400 includes a suspension supply pipe 1410, a gas supply pipe 1420, a suspension blocking unit 1430 for blocking supply of suspension from the suspension supply pipe 1410, And a discharge port 1440 in which a suspension supplied from the suspension supply pipe 1410 and a gas supplied from the gas supply pipe 1420 are mixed and sprayed, The suspension may be in an on-state such that the suspension flows from the suspension supply pipe to the discharge port, and may be off-state such that suspension from the suspension supply pipe to the discharge port is blocked when no gas is supplied from the gas supply pipe .

The suspension supply pipe 1410 can communicate with the suspension supply unit to supply the suspension. The gas supply pipe may supply gas to discharge the suspension supplied from the suspension at a controlled flow rate and speed, and the gas supply pipe may be connected to a device such as an air pump.

The diameter of the suspension outlet of the drip free atomizing nozzle may be 100 to 1000 mu m.

If the diameter of the suspension outlet of the drip free atomizing nozzle is less than 100 μm, it may be difficult to increase the suspension flow rate. If the diameter of the suspension outlet of the drip free atomizing nozzle exceeds 1000 μm, control of the suspension flow rate regulator Capacity, and even if supplied, it may be difficult to coat uniformly because of the large amount of particles.

The suspension supply flow rate of the suspension supply part may be 1 g / min to 2000 g / min.

If the suspension supply flow rate of the suspension supply unit is 1 g / min, the productivity may deteriorate due to a decrease in coating efficiency. If the suspension supply flow rate of the suspension supply unit exceeds 2000 g / min, the control capacity of the suspension flow rate adjustment apparatus is exceeded, Even if supplied, it may be difficult to coat uniformly since the amount of particles is large.

The suspension supply unit may further include a flow rate adjusting device 1600 for adjusting the suspension flow rate and a flow rate measuring device 1700 for measuring the suspension flow rate.

The drip free atomizing nozzle may further include a blocking member for blocking the vacuum chamber and the suspension supply unit when the suspension is not supplied from the suspension supply unit.

3 shows a suspension supplied by a plasma sprayed in a vacuum suspension plasma spraying apparatus and a drip free atomizing nozzle according to an embodiment of the present invention.

Referring to FIG. 3, the drip free atomizing nozzle may be arranged to supply the suspension 200 to the plasma 100 ejected from the plasma gun.

The suspension 200 is supplied through the drip free atomizing nozzle to be injected into the plasma flame 100 and then decomposed by the plasma flame 100 to heat and melt the solid particles 210, Volatilization of the molten metal 220 and acceleration of the molten metal can be performed, and a dense and thick coating can be formed in a short time in a vacuum or an inert atmosphere.

The drip free atomizing nozzle may be configured to communicate with the suspension supply unit and supply the suspension supplied from the suspension supply unit at a predetermined flow rate to the plasma.

The drip free atomizing nozzle can supply the suspension in a controlled flow rate and controlled geometry. The drip-free atomizing nozzle may be supplied to the plasma, preferably in the form of separated droplets or droplets, rather than supplying the suspension to the plasma in a continuous form.

Vacuum Suspension plasma  How to spray

4 shows a flow diagram of a vacuum suspension plasma spraying method according to an embodiment of the present invention.

Referring to FIG. 4, a vacuum suspension plasma spraying method according to an embodiment of the present invention is a method of forming a coating layer using a vacuum suspension plasma spraying apparatus, comprising: preparing a suspension and a substrate; And disposing the substrate in a vacuum chamber; And forming a coating layer on the substrate, wherein the suspension is a mixture of a powder and a solvent, and the powder is a mixture of a metal powder, an oxide-based ceramic powder and a non-oxide-based ceramic powder Wherein the solvent comprises at least one of water, alcohol, benzene, or toluene, and wherein the vacuum suspension plasma spray apparatus includes a drip free atomizing nozzle arranged to supply a suspension.

First, the steps of preparing the suspension and the substrate will be described.

The suspension is a mixture of powder and solvent, and the powder includes at least one of metal powder, oxide ceramic powder and non-oxide ceramic powder, and the solvent includes at least one of water, alcohol, benzene, or toluene .

The diameter of the powder may be 10 to 1000 nm.

When the diameter of the powder is 10 nm or less, the kinetic energy of the particles is low and it may be difficult to produce a powder having a size of 10 nm. Also, when the diameter of the powder is more than 1000 nm, the powder may not form a dense thin film.

The substrate may include at least one of a ceramic substrate, a metal substrate, and a composite substrate, but is not particularly limited thereto. In addition, the shape of the substrate is not particularly limited and can be used.

Next, the step of disposing the substrate in the vacuum chamber will be described.

The vacuum chamber is a space for performing vacuum suspension plasma spraying, and the inner atmosphere can be controlled to a pressure of 10 to 500 mbar. In addition, the vacuum chamber may be controlled to an atmosphere containing at least one of argon, helium or nitrogen, which is an inert atmosphere, in order to minimize the effect of the atmosphere when the vacuum suspension plasma spraying is performed.

If the pressure inside the vacuum chamber is less than 10 mbar, a large amount of energy may be required to maintain the atmosphere in the plasma chamber. If the pressure inside the vacuum chamber exceeds 500 mbar, the uniformity of the coating layer may deteriorate due to the small size of the plasma flame. .

The plasma gun may be disposed in the vacuum chamber, and may include a plasma generating unit for generating plasma and a plasma ejecting opening for ejecting the generated plasma. The plasma generator includes a cathode and an anode for generating a plasma, and a mainstream gas generating a plasma may be injected into the plasma generator.

The substrate may be arranged to correspond to the plasma in the vacuum chamber. The substrate can be rotated at a constant speed by the substrate control means, thereby forming a uniform coating layer.

Next, the step of forming the coating layer on the substrate by performing the vacuum plasma spraying using the suspension supplying part of the vacuum suspension plasma spraying apparatus will be described.

The vacuum plasma spraying apparatus includes a drip free atomizing nozzle arranged to supply a suspension.

The drip free atomization nozzle may be arranged to supply a suspension to the plasma ejected from the plasma gun. The drip free atomizing nozzle may be configured to communicate with the suspension supply unit and supply the suspension supplied from the suspension supply unit at a predetermined flow rate to the plasma.

The drip free atomizing nozzle 1400 includes a suspension supply pipe 1410, a gas supply pipe 1420, a suspension blocking unit 1430 for blocking the supply of suspension from the suspension supply pipe 1410, And a discharge port 1440 through which gas supplied from the gas supply pipe 1420 is mixed with the suspension supplied from the suspension supply pipe 1410 and the gas supplied from the gas supply pipe 1420. When the gas is supplied from the gas supply pipe, The suspension may be in an on-state such that the suspension flows, and in a case where no gas is supplied from the gas supply pipe, the suspension may be off-state such that suspension from the suspension supply pipe is blocked to the discharge port.

The drip free atomizing nozzle can supply the suspension in a controlled flow rate and controlled geometry. The drip-free atomizing nozzle may be supplied to the plasma, preferably in the form of separated droplets or droplets, rather than supplying the suspension to the plasma in a continuous form. Accordingly, the vacuum suspension plasma spraying method according to the embodiment of the present invention does not require separate granulation, and can decompose the suspension, heat and melt the solid particles, accelerate the melt, and form a dense and thick coating in a short time have.

Example

Example 1

Preparing Suspension

8 wt% YSZ commercial powder (Northwest Mettech Corp.) having an average particle size distribution of 200 nm was added to the ethanol solvent at a concentration of 10 wt%, and a suspension in which the YSZ powder was uniformly dispersed was prepared using a stirrer.

Substrate preparation

A Ni-based super heat resistant alloy substrate was prepared as a substrate to be subjected to vacuum suspension plasma spraying. NiCoCrAlY (Oerlikon Metco, particle size 40 μm, composition Co 18.0 - 26.0, Cr 13.0 - 21.0, Al 10.0 - 15.0, Y 0.1 - 1.0 and residual Ni) powder was used as a bonding coating layer on the Ni series super heat resistant alloy substrate. Layer was deposited to a thickness of 200 [mu] m.

Vacuum Suspension plasma Spray layer  formation

A substrate prepared before a vacuum chamber controlled at a nitrogen pressure of 1000 mbar was placed.

A plasma gun was placed in the vacuum chamber, and argon and hydrogen were injected into the plasma gun as a mainstream gas to generate a plasma. The flow rate of the atmosphere gas was adjusted so that the pressure of the chamber was maintained at 400 mbar, and the distance between the plasma gun and the substrate was adjusted to 80 mm.

A YSZ coating layer having a thickness of 100 탆 was formed while supplying the suspension prepared before the plasma at a flow rate of 50 g / min.

5 is a photograph of a vacuum suspension plasma spray coating surface and side cross-section formed by Example 1. Fig. Referring to FIG. 5, it can be seen that the YSZ coating layer is densely coated on the NiCoCrAlY junction layer.

Example 2

Preparing Suspension

8 wt% YSZ commercial powder (Northwest Mettech Corp.) having an average particle size distribution of 200 nm was added to the ethanol solvent at a concentration of 10 wt%, and a suspension in which the YSZ powder was uniformly dispersed was prepared using a stirrer.

Substrate preparation

A Ni-based super heat resistant alloy substrate was prepared as a substrate to be subjected to vacuum suspension plasma spraying. A NiCoCrAlY layer was deposited as a bonding coating layer on the Ni-based super-high temperature alloy substrate to a thickness of 200 μm.

Vacuum Suspension plasma Spray layer  formation

A YSZ coating layer having a thickness of 150 탆 was formed in the same manner as in Example 1 except that the vacuum plasma spraying pressure was adjusted to 250 mbar and the distance between the plasma gun and the substrate was adjusted to 70 mm .

6 is a photograph of the surface of the vacuum suspension plasma spray coating formed by Example 2 and the side cross-section thereof. Referring to FIG. 6, it can be seen that the YSZ coating layer is densely coated on the NiCoCrAlY junction layer.

Example 3

Preparing Suspension

8 wt% YSZ commercial powder (Northwest Mettech Corp.) having an average particle size distribution of 200 nm was added to the ethanol solvent at a concentration of 10 wt%, and a suspension in which the YSZ powder was uniformly dispersed was prepared using a stirrer.

Substrate preparation

A Ni-based super heat resistant alloy substrate was prepared as a substrate to be subjected to vacuum suspension plasma spraying. A NiCoCrAlY layer was deposited as a bonding coating layer on the Ni-based super-high temperature alloy substrate to a thickness of 200 m.

Vacuum Suspension plasma Spray layer  formation

A YSZ coating layer having a thickness of 50 탆 was formed in the same manner as in Example 1 except that the vacuum plasma spraying pressure was adjusted to 100 mbar in Example 1 and the distance between the plasma gun and the substrate was adjusted to 90 mm .

7 is a photograph of a vacuum suspension plasma spray coating surface and side cross-section formed by Example 3. Fig. Referring to FIG. 7, it can be seen that the YSZ coating layer is densely coated on the NiCoCrAlY junction layer.

Example 4

Preparing Suspension

8 wt% YSZ commercial powder (Northwest Mettech Corp.) having an average particle size distribution of 200 nm was added to the ethanol solvent at a concentration of 25 wt%, and a suspension in which the YSZ powder was uniformly dispersed was prepared using a stirrer.

Substrate preparation

A Ni-based super heat resistant alloy substrate was prepared as a substrate to be subjected to vacuum suspension plasma spraying. A NiCoCrAlY layer was deposited as a bonding coating layer on the Ni-based super-high temperature alloy substrate to a thickness of 200 m.

Vacuum Suspension plasma Spray layer  formation

The YSZ film was formed to a thickness of 270 탆 under the same conditions except for the change of the YSZ weight content of the suspension in Example 1 above.

8 is a photograph of a vacuum suspension plasma spray coating surface and side cross-section formed according to Example 4. Fig. Referring to FIG. 8, it can be seen that the YSZ coating layer is densely coated on the NiCoCrAlY junction layer.

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The present invention is not limited to the above-described embodiment and the accompanying drawings, but is intended to be limited by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

1000: Vacuum Suspension Plasma Sprayer
1100: Vacuum chamber
1200: Pressure regulator
1300: Plasma gun
1400: Drip-free atomization nozzle
1410: Suspension supply pipe 1420: Gas supply pipe
1430: Suspension interrupter 1440: Suspension outlet
1500: Suspension supply
1600: Flow regulator
1700: Flow measuring device
100: Plasma
200: Suspension
210: Particle 220: Solvent

Claims (8)

A vacuum chamber;
A pressure regulating device for maintaining the pressure inside the vacuum chamber at 10 to 500 mbar;
A plasma gun disposed in the vacuum chamber, the plasma gun including a plasma generating unit generating a plasma and an ejection port ejecting the generated plasma;
A drip free atomizing nozzle arranged to supply a suspension to the plasma ejected from the plasma gun; And
And a suspension supply part communicating with the drip free atomizing nozzle and supplying the suspension to the drip free atomizing nozzle,
The suspension may be a mixture of powder and solvent, and the powder may include at least one of metal powder, oxide ceramic powder and non-oxide ceramic powder, and the solvent may include at least one of water, alcohol, benzene, and toluene and,
The drip free atomizing nozzle includes a suspension supply pipe, a gas supply pipe, a suspension blocking unit for blocking discharge of the suspension from the nozzle, a suspension supplied from the suspension supply pipe, and a gas supplied from the gas supply pipe, And a discharge port for discharging the vacuum suspension plasma.
The method according to claim 1,
The suspension blocking portion is in an open state such that a suspension flows from the suspension supply pipe to the discharge port when gas is supplied from the gas supply pipe. When the gas is not supplied from the gas supply pipe, Is in a closed state (Off-state) so that the suspension is blocked.
The method according to claim 1,
Wherein the diameter of the suspension outlet of the drip-free atomizing nozzle is 100 to 1000 mu m.
The method according to claim 1,
And the suspension supply flow rate of the suspension supply unit is 1 to 2000 g / min.
The method according to claim 1,
Wherein the suspension supply unit further comprises a flow rate adjusting device for adjusting a suspension flow rate and a flow rate measuring device for measuring a suspension flow rate.
The method according to claim 1,
Wherein the drip free atomizing nozzle further comprises a blocking member for blocking the vacuum chamber and the suspension supply unit when no suspension is supplied from the suspension supply unit.
A method of forming a coating layer using a vacuum suspension plasma spraying apparatus,
Preparing a suspension and a substrate; And
Disposing the substrate in a vacuum chamber; And
Supplying the suspension to the plasma, and forming a coating layer on the substrate,
The suspension is a mixture of powder and solvent, and the powder includes at least one of metal powder, oxide ceramic powder and non-oxide ceramic powder, and the solvent includes at least one of water, alcohol, benzene or toluene, The vacuum suspension plasma spraying apparatus includes a drip free atomizing nozzle arranged to supply a suspension, and the drip free atomizing nozzle blocks the suspension supply pipe, the gas supply pipe, and the suspension from being discharged from the nozzle to the inside of the nozzle Wherein the suspension blocking portion includes a suspension blocking portion, a suspension supplied from the suspension supply pipe, and a discharge port through which a gas supplied from the gas supply pipe is mixedly injected, wherein the suspension blocking portion includes a suspension from the suspension supply pipe to the discharge port when the gas is supplied from the gas supply pipe, Open phase to flow Wherein the suspension tube is in an on-state, and when gas is not supplied from the gas supply pipe, the suspension is shut off from the suspension supply pipe to the discharge port in an off-state.
8. The method of claim 7,
Wherein the powder has a diameter of 10 to 1000 nm.

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