WO2010056077A9

WO2010056077A9 - High-hardness coating powder, and preparation method thereof

Info

Publication number: WO2010056077A9
Application number: PCT/KR2009/006719
Authority: WO
Inventors: 박희섭; 류민호; 엠 다우쉬왈리드; 홍순형
Original assignee: 일진다이아몬드(주)
Priority date: 2008-11-14
Filing date: 2009-11-16
Publication date: 2010-10-07
Also published as: WO2010056077A2; KR20100054511A; WO2010056077A3; KR101492969B1

Abstract

The present invention provides a method for preparing of high-hardness coating powder to easily coat the surface of a base with a coating material, said method comprising the steps of (a) dissolving a first chlorine (Cl)-based salt and a second fluorine (F)-based salt into a solvent to obtain a solution, (b) mixing a base, and a coating material containing titanium, with the solution, and drying the mixture, (c) putting the mixture obtained in said step (b) into a reaction furnace, and (d) heating the reaction furnace at a predetermined temperature, and keeping the reaction furnace at said predetermined temperature to cause a molten salt reaction wherein said first salt and said second salt are molten. The present invention also provides a high-hardness coating powder prepared by said method.

Description

High hardness-coated powder and a method of manufacturing the same

The invention more particularly relates to also a powder coating and a method of manufacturing a high hardness, to a powder produced by the method and a method to easily coat the coating material on the surface of the base material.

The cutting tool wear occurs as a continuous cutting process proceeds. Thus, the cutting tool has high hardness and is formed using the materials. By typically mixing and sintering a base material and a metal, such as diamond forms the cutting tool.

For the durability of the cutting tool, it is important the bonding of the base material and the metal. In addition, the sintering temperature is high temperature, so it is important that the high temperature stability and anti-oxidation of the base surface of the base material.

Prior to sintering by mixing the base material and the metal for them has been a technique of forming a coating layer on the surface of the base study. By coating the surface of the base material can be prevented from oxidation and increase the bonding strength between the metal and improving the high temperature stability.

However, that is the particles of the base material submicrometer several nanometers to several if the fine particles of the micrometer is in the process of coating the coating material on the surface of the base the base material is agglomerated, and the coating material is coated nonuniformly on the surface of the base high hardness coating powder there is a limit to obtain.

The invention has high hardness can be easily coated with the coating material to the surface of the base material can provide a powder coating and a method of manufacturing the same.

The invention (a) chlorine (Cl) forming a first solution by dissolving the second salt of a primary salt, a fluorine (F) based on a solvent-based, (b) placing a coating material containing a base material, the titanium in the solution mixing and drying, (c) the first salt and the second salt is melted by holding step for loading the reactor the mixture obtained in step (b) and (d) after heating the reactor to a predetermined temperature which also discloses a method for manufacturing a high-hardness coating powder comprising a molten salt reaction step takes place.

The first salt in the present invention may include at least two selected from the group consisting of KCl, NaCl and BaCl2.

In the present invention, the second salt may include at least one selected from the group consisting of NaF, K ₂ TiF ₆ and NaK ₂ TiF _6.

In the present invention the solvent may comprise ethanol.

In the present invention, the step (d) may be carried out at 800 ℃ to 1000 ℃.

In the present invention, the step (d) may be carried out the reaction with stirring in an Ar gas atmosphere inside the reactor.

In the present invention then proceeds to the step (d) may comprise the step of the reaction steps of the sonication, insert the powder obtained after the reaction in the molten salt in the reaction solution in distilled water and hydrochloric acid and.

And then proceed to step (d) in the present invention may further comprise the step of removing the coating material remaining in the wet chaejil method.

And then proceed to step (d) in the present invention may comprise the step of the crystallization proceeds by heat treatment in a hydrogen atmosphere.

In the present invention, the base powder may comprise a freezing one selected from the group consisting of diamond, cubic boron nitride and a carbon nanotube.

According to another aspect of the present invention also discloses a coating of high hardness powders produced by the production method of claim one of the above methods.

High hardness coating powder and its manufacturing method are uniform the coating material to the surface of the base material comprising the fine particles to the coating to improve the strength and improve the surface properties high hardness at high temperature stability superior in accordance with the present invention it is possible to obtain a coating powder.

Figure 1 is a high-hardness of the present invention is also a flow chart sequentially showing a method of manufacturing a coated powder.

2 is a view showing the device with a schematic for explaining the manufacturing method of Fig. 1 in Fig.

Figure 3 is an enlarged view of A of FIG.

Figure 4 is a photograph of measuring a powder formed according to the production method of the high hardness coating powder according to an embodiment of the present invention with an electron microscope.

5 is a diagram showing the X-ray (X-ray) diffraction pattern of the powder of Fig.

6 is a view of measuring a powder formed according to the production method of the high hardness coating powder according to another embodiment of the present invention with an electron microscope.

7 is a view showing the X-ray diffraction pattern of the powder of Fig.

8 is a view of measuring the cross-section of Figure 6 using a focused ion beam (FIB) powder.

9 is a view of measuring the cross-section of the powder of Figure 6 using a transmission electron microscope (TEM).

10 is a view showing the measurement of components of the B part of Fig.

11 is a view of measuring the cross-section using a transmission electron microscope after the heat treatment of the powder of Fig.

12 is a diagram showing a diffraction pattern of a limited field of view 11.

13 is a view for explaining a glass transition temperature of the powder of Fig.

14 is a view of measuring a powder formed according to the production method of the high hardness coating powder according to still another embodiment of the present invention with a transmission electron microscope.

Figure 15 is an enlarged view of the FIG. 14 C.

16 is a view showing the restricted field of view of the powder diffraction pattern of FIG.

200: with electric: 210 in reaction

202: crucible 203: thermocouple

204: stirrer 205: gas inlet

206: gas outlet 310: a molten salt

320: 330 base dressings

Embodiment of the invention illustrated in the accompanying drawings with reference to an example will be described the construction and operation of the present invention;

1 is a view showing the device with a schematic for explaining the manufacturing method of the high-hardness Fig 2 is a flow chart sequentially showing a method of manufacturing a coated powder according to the present invention; Fig.

Hardness method of manufacturing a coated powder according to the present embodiment Referring to Figure 1 for example, a first salt, comprising the steps of mixing by placing a step 101, the base material, the coating material in the solution to form a solution by dissolving the second salt in the solvent (102 ), removing the drying step 103, the steps for loading the dry mixture in the reactor 104, a step of heating and maintaining the reactor 105, a step to remove residual salt (106), and the remaining coating material to 107 and a step 108 for heat treatment.

Prepare the members required for the production process related to the embodiment before proceeding with the steps of this example.

The primary salt contains at least two selected from the group consisting of KCl, NaCl and the BaCl2 salt of chlorine series. In that the molten salt as a step to be described later to lower the melting temperature to select two or more salt to ensure the safety and high-temperature molten salt in a uniform distribution. That is, the first salt may include two or more salts. That is, the first salt may be KCl and NaCl, may be BaCl2 and NaCl, may be KCl and BaCl2. In addition, the primary salt may be NaCl and KCL and BaCl2.

The second salt comprises at least one selected from the group consisting of NaF, K ₂ TiF ₆ and NaK ₂ TiF _6.

The base material has a number particle size of less than a micrometer can be formed by using various materials. The base material comprises any one selected from the group consisting of a high hardness diamond, cubic boron nitride and a carbon nanotube.

First, for convenience of description it will be described an embodiment of the case of using a diamond base material.

The coating material comprises a titanium. Titanium is coated on the surface of the base particles comprising diamond and prevents oxidation of the base material particle surfaces and to ensure the safety at a high temperature and improve the bonding strength of the cutting tool in forming the base material powder and the metal powder at a later date. Dressings can be prepared in various forms. In other words the coating material may be a powder, a foil, a pellet form. But it is easily uniformly molten in a reaction to take place the coating material is preferably in powder form.

Preparing each material, and then, first forming a second solution by dissolving a first salt and a second salt in a solvent. At this time, the solvent may be ethanol. Then put the base powder containing the diamond in place the coating material solution containing titanium in solution.

Then the stirring the mixture to form the powder mixture to create a uniform dry.

The particle size of the base powder containing the diamond is a micrometer or less. Preferably less than 5 nanometers 5 micrometers.

To the particle size of the base powder containing the diamond is less than 5 nanometers, a dispersion is well designed aggregation between the base powder particles by the force of Van der Waals between each base material powder up coating the coating material in each of the base powder it is limited. So it is preferable that the particle size of the base powder containing the diamond is less than 5 nanometers.

Also, if the particle size of the base powder containing the diamond is more than 5 microns decreases the toughness of the cutting tool in the case of forming a cutting tool with a base material. Therefore, the particle size of the base powder containing the diamond is preferably not more than 5 micrometers.

Since the particle size of the base powder is small in the process of coating a coating material on the surface of the base particles are to each other the base material particles is agglomerated with each other by the force (van der Waals' force) of the van der Waals.

However, in this embodiment, using the ethanol to form a first solution by dissolving a first salt and second salt, the base material and coating material. Through which facilitates dispersion of the individual particles. In particular, the process of forming the solution and then stirred evenly made as uniform dispersion of the particles. And it can remove unwanted solvent component by drying to form a powder mixture of a first salt in a uniform state, and the second salt, a base material and coating material.

And then it performs the step of melting the mixed powder. And FIG. Referring to Figure 2 into the mixed powder shown in the reaction to proceed with the process schematically.

And the reactor 200 comprises an electric 201, the crucible 202, the thermocouple 203, the agitator 204, a gas inlet 204 and gas outlet 205. The above-described mixed powder is put in a crucible (202). Encompassing the crucible 202 has a mixed powder in supplying heat from an electrically 201. Crucible 202 may be molten. Into an electric (201) is a method of supplying heat by using electric energy. However, the present invention if it can supply the heat needed to melt the mixed powder in the crucible 202 is not limited to this it is possible to use various forms of heat source.

The temperature in the process and the process of agitation which the molten powder mixture using a thermocouple 203 can measure and control the heat supply of the electric furnace supplying heat to the crucible (202) (201). The first salt is a mixed powder is melted, the reaction in which the second molten salt is to take place at 800 ℃ to 1000 ℃.

The first salt and the second salt the melting temperature is at least about 600 ℃. Also the reaction rate by diffusion of titanium atoms when the molten coating material containing titanium is proportional to the temperature. The melting temperature of the atmosphere is less than 800 ℃ decreases the uniformity of the reaction after the speed of the diffusion of titanium atoms away from the coating material is coated on a base material formed of the coating layer. Thus, the mixed powder is first melted salt, which is the second reaction salts melt is adjusted to take place at more than 800 ℃.

In addition, the atmosphere at a temperature exceeding 1000 ℃ durability is weakened by embrittlement of the base material. Thus, the mixed powder is first melted salt, which is the second reaction salts melt is adjusted to occur in less than 1000 ℃.

Agitator 204 when the mixed powder is melted so that the first salt and second salt, the base material and cover material are stirred evenly. Stirrer 204 is preferably in the form of an impeller (impeller).

The argon (Ar) gas is introduced and discharged through the gas entrance 205 and a gas outlet (206). This reaction can melt the mixed powder inside the crucible may take place in an inert atmosphere throughout.

Figure 3 is an enlarged view of A of FIG. With reference to Fig. 3 there is shown that when one of the first salt and the second salt is a base material 320 and cover material 330 to the molten salt melt (310) evenly distributed.

The mixed powder is melted in the crucible (202) for a period of time while remaining coating material is coated on the surface of the coating material is a base material by an oxidation and reduction reaction in the molten salt. Specifically, the following reactions take place in sequence.

(1) Ti-> 2Ti ²⁺

^{(2) 2Ti 2+ -> Ti} + Ti 4+

(3) C (diamond) + Ti-> TiC

First, in the claim 1, a salt and the second salt is a molten salt melted coating material is melted causing a reaction of (1) of the above reaction. In particular, with ₂ TiF ₆ or K ₂ TiF ₆ as NaK second salt, the second molten salt so as to form a tetravalent titanium ions in the molten salt Ti + Ti ⁴⁺ -> causing a reaction of ² 2Ti.

The surface of the base powder causing a reaction of the above (2) reaction. That is titanium divalent ions formed in the molten salt is reduced in the base material surface. The generated tetravalent titanium ions again promotes the oxidation reaction of titanium in a molten salt.

And then causing a reaction of the base metal surface (3). I.e. by the diamond and titanium to react at high temperature in the surface of the particles of the base material containing the diamond to form titanium carbide. I.e., to form the coated powder coating material is coated on the surface of the base material.

A coated powder collected in a crucible 202 is because lumps immediately after the melting of the high temperature end. In addition, because the salts and the cover material remained without reacting with the base material in a melting process to stick together with the powder coating process is required to remove these.

First and stirred into the powder to stick together in the coating powder and the remaining salts and the residual coating material in distilled water to remove residual salts. Then remove salts remaining in the ultrasonic treatment. At this time can be quickly and easily advance the process to a hydrochloric acid solution was added after the ultrasonic treatment.

After removal of the remaining salt and remove the base material and the coating material which remains unreacted. The powder coating material remaining over the wet chaejil can be easily removed. I.e., releasing the powder, which remains coated with the titanium powder to stick together in a liquid such as distilled water to chaejil a liquid form of a powder to remove residual titanium powder.

Then, using a centrifuge to remove the solution employed during the wet chaejil. And it can be removed by the addition of distilled water to dissolve the remaining salt in a very small amount.

Then the coating powder is recovered by vacuum filtering. That is, recovering the diamond powder is coated with titanium.

The recovered coated powders are heat treated after drying in a vacuum atmosphere. Heat treatment proceeds in a hydrogen atmosphere at temperatures above 800 ℃. This titanium carbide formed on the surface of the base through the crystallization and improving the adhesion between the base material and the coating material and improves the durability.

Figure 4 is a photograph of measuring a powder formed according to the production method of the high hardness coating powder according to an embodiment of the present invention with an electron microscope, Figure 5 is showing the X-ray (X-ray) diffraction pattern of the powder of Fig. 4 diagram.

More specifically, the primary salt using KCl, NaCl and BaCl ₂ and NaF and a NaK ₂ TiF ₆ was used as the second salt. KCl, NaCl and BaCl2 are ready to 10g, respectively, were prepared in 10g NaF and 5g of NaK2TiF6. The base material contains a diamond, and the diamond particles have a size less than 1.5 micrometer. The coating material is made ready to 2g of titanium powder was titanium powder have a particle size of 100mesh.

When Fig. 4 (a) to FIG. 4, 4 (c) Preparation method diamond prior to using the powder, and Fig. 4 (b) is a formula in the coating material is coated with diamond powder of the present example, in the example is a scanning electron microscope (SEM) pictures indicating that the enlarged view 4 (b).

Figure 4 (a) and Figure 4 (b) and may be compared to 4 (c) shows that the surface of respective particles of the base powder containing the diamond coating material is coated. Referring to Figure 5 it is possible to easily determine the components thereof. (A) of Figure 5 (b) of the diamond powder, 5 prior to the coating by the method of the present example is a measure of the diamond powder after the coating by the method according to the present embodiment; The peak marked with an inverted triangle is to exist in both the (a) and 5 (b) This refers to the diamond component. However circled peak is present only in (b) of Figure 5, which indicates a titanium carbide. This is the titanium on the surface of the fine diamond particles produced by the method according to this embodiment can be seen that through evenly coated.

Figure 6 is a view of measuring a powder formed according to the production method of the high hardness coating powder according to another embodiment of the present invention with an electron microscope, Figure 7 is a view showing the X-ray diffraction pattern of the powder of Fig.

For convenience of explanation will be described about the embodiment different from that described above. The present embodiment is the use of the difference between the base material as compared to the embodiments described above cubic boron nitride instead of diamond.

To form a first solution by dissolving a first salt and a second salt in a solvent as in the above-described embodiments. At this time, the solvent may be ethanol. Then put the base powder containing the cubic boron nitride in a solution put the coating material containing titanium in solution. Then the stirring the mixture to form the powder mixture to create a uniform dry.

The particle size of the base powder containing the cubic boron nitride is a micrometer or less. Preferably less than 50 nanometers 5 micrometers.

The particle size of the base powder containing the cubic boron nitride is less than 50 nm is a limit to coat the coating material on each of the base metal powder particles designed well-disperse up agglomeration by the force of Van der Waals between each cubic boron nitride particles, have. So, the particle size of the base powder containing the cubic boron nitride is preferably not less than 50 nanometers.

Also, if the particle size of the base powder containing the cubic boron nitride is more than 5 microns decreases the toughness of the cutting tool in the case of forming a cutting tool with a base material. Therefore, the particle size of the base powder containing the cubic boron nitride is preferably not more than 5 micrometers.

The mixed powder is melted in the crucible (202) for a period of time while remaining coating material is coated on the surface of the coating material is a base material to the oxidation and reduction reactions in the molten salt. Specifically, the following reaction takes place.

(1) Ti-> 2Ti ²⁺

^{(2) 2Ti 2+ -> Ti} + Ti 4+

(3) 3Ti + 2BN-> TiB 2 + 2TiN

The surface of the base powder causing a reaction of the above (2) reaction. That is titanium divalent ions formed in the molten salt is reduced in the base material surface.

And then causing a reaction of the base metal surface (3). I.e. by the boron and titanium, the nitrogen and titanium to react at high temperature in the surface of the particles of the base material containing cubic boron nitride to form a titanium boride and titanium nitride.

Then hardness proceeds to the subsequent steps such as removing residual salt, the remaining coating material is removed, and heat-treating the coating material to the surface of the base material is also coated to obtain a coated powder. Specific details of the subsequent steps is omitted the same as in the foregoing embodiments.

When Fig. 6 (a) to Figure 6 is a cubic boron nitride powder prior to using the manufacturing method according to this embodiment, FIG. 6 (b) covering the coated cubic boron nitride powder in a manufacturing process of the present example, FIG. 6 (c) is a scanning electron microscope (SEM) pictures indicating that the close-up 6 (b) Fig.

Figure 6 (a) and Figure 6 (b) and a coating material to the surface of the individual particles of the base powder containing the cubic boron nitride can be seen that the coated and compared to 6 (c). Referring to Figure 7 it is possible to easily determine the components thereof. (A) of Figure 7 (b) of cubic boron nitride powder, 7 prior to the coating by the method of the present example is a measure of the cubic boron nitride powder after the coating by the method of the present example will be. The peak indicated by the inverted triangle to exist in both the (a) and 7 (b) This refers to the cubic boron nitride component. However circled peak is present only (b) of Figure 7, and which refers to the titanium nitride. This is the titanium on the surface of fine cubic boron nitride particles by the production process related to the present embodiment can be seen that through evenly coated.

Referring to Figure 8 it can be seen that the formed uniform coating layer containing titanium is formed on the surface of the cubic boron nitride. In Figure 8 a) the part that points is a layer for protecting the surface of the sample from a platinum (Pt), focused ion beam (FIB) with a protective layer formed in order to experiment. In Figure 8 b) the coating layer and the c) is the base material in Fig. Referring to Figure 8 in the form of a thin film to the thickness of the coating layer 200nm.

Figure 9 is a view of measuring the cross-section of the powder of Figure 6 using a transmission electron microscope (TEM), FIG. 10 is a view showing the measurement of components of the B part of Fig.

In Figure 9 (a) has the base portion, (c) the covering layer portion and (b) shows a boundary between the base material and the coating layer. 10 is a graph showing a composition analysis result of each section. In Figure 10 (a) is boron, (b) is a nitrogen, (c) an oxygen, (d) refers to the titanium.

Referring to Figure 10 (a) the base part forms the nitrogen, boron main ingredient because it contains a cubic crystal boron nitride. And a coating material of titanium increases in a boundary portion (b), and most of the titanium present in the coating layer (c) portion. It is the coating material containing titanium on the surface of the particles of the base material containing cubic boron nitride can be seen that reliably covered with the via.

11 is a view and Figure 12 a measure of the cross-section using a transmission electron microscope after the heat treatment of the powder of Fig. 6 is a diagram showing a diffraction pattern of a limited field of view 11. In Figure 11 a) refers to the coating point to the base material b). 11 and 12 the coating layer containing titanium has a polycrystalline structure consisting of crystals with a size of less than several tens of nanometers.

13 is a view for explaining a glass transition temperature of the powder of Fig. Specifically, the left Y-axis coordinates in Fig. 13 is a differential scanning calorimetry (differential scanning calorimetry; DSC) indicates that a measure of the heat flow by, and shows that the higher the temperature reduces the heat flow, the right side of Fig. 13, the Y-axis coordinates indicates a value that varies according to the fine temperature variation as a differential heat flow the value of the left Y coordinate values. Referring to Figure 13, a glass transition temperature of around 950 ℃. This means that the coating layer containing titanium on cubic boron nitride surfaces crystallized at 950 ℃ and out in an amorphous state. The present invention can easily form a crystallized coating layer as above and heat treating the coated mother material powder in a hydrogen atmosphere.

Figure 14 is a view of measuring a powder formed according to the production method of the high hardness coating powder according to still another embodiment of the present invention with a transmission electron microscope, Figure 15 is an enlarged view of the 14 C. 16 is a view showing the restricted field of view of the powder diffraction pattern of FIG.

For convenience of explanation will be described about the embodiment different from that described above. The present embodiment is the difference between the base material as compared with the above embodiment the use of the carbon nanotube instead of diamond or cubic boron nitride.

To form a first solution by dissolving a first salt and a second salt in a solvent as in the above-described embodiments. At this time, the solvent may be ethanol. Then insert the base material containing carbon nanotubes in a solution put the coating material containing titanium in solution. Then the stirring the mixture to form the powder mixture to create a uniform dry.

The particle size of the base powder containing the carbon nanotube is a micrometer or less. Preferably at least 5 nanometers greater than 50 nanometers.

The particle size of the base powder containing the carbon nanotubes is less than 5 nanometers to each base powder particle designed well the distribution of the base metal powder particles up agglomeration between particles by the force of Van der Waals between each base powder particle there is a limit to coat the coating material. So it is preferable that the particle size of the base powder containing the diamond is less than 5 nanometers.

Also, if the particle size of the powder of the base material containing carbon nanotubes greater than 50 nanometers it decreases the toughness of the cutting tool in the case of forming a cutting tool with a base material. Therefore, the particle size of the powder of the base material containing carbon nanotubes is preferably not more than 5 micrometers.

(1) Ti-> 2Ti ²⁺

^{(2) 2Ti 2+ -> Ti} + Ti 4+

(3) Ti + C (CNT) -> TiC

And then causing a reaction of the base metal surface (3). That is to the carbon and titanium to react at high temperature in the surface of the particles of the base material including the carbon nanotubes to form the titanium carbide.

When 14 and 15 it can be seen that the coating layer formed on the surface of the carbon nanotubes, the base material. In addition, it can be seen that even through the covering material 16 containing titanium on the surface of the carbon nanotube is coated the titanium carbide formed in the coating layer.

This is the titanium on the surface of fine cubic boron nitride particles by the production process related to the present embodiment can be seen that through evenly coated.

It has been described in the embodiment shown in the drawings as it will be understood that it is the only, and those skilled in the art various modifications and equivalent other embodiments are possible from it as exemplary. Therefore, the true technical protection scope of the invention as defined by the technical spirit of the appended claims.

Carbon nanotubes may be, and studies to use a cutting tool of a material having a high strength, high elastic coefficient, high electrical conductivity, high thermal conductivity characteristic of the. However, when using the carbon nanotubes in the base material and the binding force is evenly distributed and the coating material is a problem in the interface.

In this embodiment, it is possible to uniformly coat the coating material containing titanium on the surface of the base material containing carbon nanotubes. Hardness of a high hardness and improved surface properties improved through which also it is possible to easily form a coating powder.

Claims

(A) chlorine (Cl) forming a first solution by dissolving the second salt of a primary salt, a fluorine (F) based on the solvent of the series;

(B) mixing and drying by placing a coating material containing a base material, the titanium in the solution;

(C) a step for loading the reaction mixture obtained in the step (b); And

(D) The method of the first salt and a high hardness coating that contains the molten salt takes place step reaction in which the second molten salt is kept after heating the powder to the reactor at a predetermined temperature.
According to claim 1,

It said first salt is prepared in at least two high-hardness coating powder comprising selected from the group consisting of KCl, NaCl and BaCl2.
According to claim 1,

The second salt is NaF, K ₂ TiF ₆ and NaK ₂ TiF _6, at least one high hardness method for producing a coated powder comprising selected from the group consisting of.
According to claim 1,

The solvent is a high-hardness comprising ethanol process for producing a coated powder;
According to claim 1,

The step (d) is a method for manufacturing a high-hardness coating powders to proceed at 800 ℃ to 1000 ℃.
According to claim 1,

The step (d) is a method for manufacturing a high hardness to proceed with the reaction while stirring the inside of the reactor also covered with the powder in an Ar gas atmosphere.
In the first, wherein

After then proceeding to step (d) into the powder obtained after the reaction in the molten salt to the reaction in distilled water to a sonication step; And

High hardness, comprising hydrochloric acid and also reaction process for producing a coated powder.
In the first, wherein

Method for manufacturing a high-hardness coating powder further comprises the step of proceeding to the step (d), and then removing the coating material remaining in the wet chaejil method.
In the first, wherein

And then proceed to step (d) high hardness, comprising the crystallization proceeds by heat treatment in a hydrogen atmosphere The method of coating powder.
In the first, wherein

The base metal powder production method of diamond, cubic boron nitride and a carbon nanotube-coated powder comprising a high hardness even freezing one selected from the group consisting of.
In the first, wherein

Hardness method for producing a coated powder in which the base powder comprises a diamond particle having a size of 5 nanometers to 5 micrometers.
In the first, wherein

Hardness method for producing a coated powder in which the base powder comprises a cubic boron nitride particles having a size of 50 nanometers to 5 micrometers.
In the first, wherein

Hardness method for producing a coated powder to the base material powder includes a carbon nanotube having a particle size of 5 nanometers to 50 nanometers.
Wherein any one of claims 1 to 13, wherein any one of the claim a high hardness coating powder produced by the production method of the.