KR20030032387A - Sialon powder for thermal spraying, method for making the same, and thermal spray coating method using it - Google Patents

Abstract

PURPOSE: A sialon powder which is manufactured by milling the sintered mixture after sintering a mixture of alumina (Al2O3) and silicon nitride (Si3N4), method for manufacturing the sialon powder, and a thermal spray coating method using the sialon powder are provided. CONSTITUTION: The sialon powder for thermal spraying is manufactured by milling the sintered mixture after sintering a mixture in which alumina (Al2O3) is mixed with silicon nitride (Si3N4) in a weight ratio of 1:5 to 7:2 at a temperature of 1450 to 1800 deg.C in an inert atmosphere, wherein the mixture is added to 20 to 80 wt.% of zirconium oxide (ZrO2) as the balance, wherein the mixture is added to 5 to 50 wt.% of titanium oxide (TiO2) as the balance, wherein the mixture is added to a composite additive of 20 to 50 wt.% of zirconium oxide (ZrO2) and 5 to 20 wt.% of titanium oxide (TiO2) as the balance, and wherein oxides of one or more elements selected from the group consisting of lithium, magnesium, calcium, scandium, and yttrium is added in an amount of 1 to 7 wt.% for the total weight. The method for manufacturing the sialon powder for thermal spraying comprises steps of mixing alumina (Al2O3) with silicon nitride (Si3N4) in a weight ratio of 1:5 to 7:2; sintering the mixture at a temperature of 1450 to 1800 deg.C in an inert atmosphere; and milling the sintered material. In a thermal spray coating method for thermal spraying a coating material on a matrix by detonation gun spraying or high velocity oxygen fuel spraying, the thermal spray coating method is characterized in that the sialon powder is used as the coating material.

Description

Sialon powder for thermal spray coating, preparation method thereof and thermal spray coating method using the same {Sialon powder for thermal spraying, method for making the same, and thermal spray coating method using it}

The present invention relates to a sialon powder for thermal spray coating, a method for manufacturing the same, and a thermal spray coating method using the same. More particularly, the present invention is obtained by mixing alumina and silicon nitride, followed by sintering and crushing. A spray coating for sialon powder having a coexistence form of X-sialon to be in a state and β-sialon coated without melting during the spraying process, a manufacturing method thereof, and a method of spray spraying or high-speed flame spraying using the same It is about.

In general, plasma spraying and explosion spraying are used as the nonmetal spray coating method.

When the plasma spraying method is used, the powder is exposed to plasma at a temperature of 10,000 ° C. or higher, so that sialon is decomposed, and the structure of the coating layer is not formed precisely. Alumina is formed (S. Sodeoka, K. Ueno, Y. Hagiwara and S. Kose, Journal of Thermal Spray Technology, Vol. 1 (2) June, 1992, p153). When it is used at a high temperature of 700 ℃ or more by changing the volume while causing a phase transformation into a phase alumina, there is a problem that easily cracks inside the coating layer and peels off the coating layer.

Detonation-Gun is a method of spray coating by melting powder using combustion heat that mixes gas or liquid fuel with oxygen and burns it. In general, metal is not included because of low flame temperature. It is known that it can be used as a method of thermal spray coating of a non-metal type, because the flame temperature is higher than that of flame spray and high velocity oxygen fuel (HVOF).

In addition, in the case of the thermal spraying method using some high speed flame sprayers in addition to the two thermal spraying methods, it is known that thermal spray coating of oxides such as alumina (Al ₂ O ₃ ) can be carried out.

The sialon (SiAlON) used as the thermal spray coating material of the present invention is a general term meaning a nitride oxide composed of elements of Si, Al, O, and N. Depending on the desired properties, Li, Mg, Ca, Sc, Y and other rare earth elements may be added in addition to the above four elements.

1 is a pseudo state diagram showing that various phases of sialon such as X and β may be formed according to the component ratio of Si ₃ N ₄ -AlN-Al ₂ O ₃ -SiO ₂ , and in particular, β-sialon is Si The range of components may be indicated as _6-z Al _z O _z N _8-z (0 <Z <4.2). This type of sialon (β-sialon) is excellent in high temperature oxidation resistance, excellent in mechanical strength, and excellent in corrosion resistance to molten metal, and thus can be applied to applications such as engines, cutting tools, bearings, ceramic gas turbines, and the like. It is also widely used as a protective tube for thermocouples and heating elements used in direct contact with molten aluminum and molten zinc.

Due to these excellent properties of sialon has been studied to apply to a wider range of components manufactured in the form of a coating, in particular spray coating, but did not obtain excellent results that can be used for industrial purposes.

In accordance with such a request, Japanese Patent Publication No. 194-228724 discloses the use of silicon nitride (Si ₃ N ₄ ) or sialon for rolls used in a hot dip galvanizing bath, but no method for producing the same is disclosed.

The present invention is provided in order to solve the above-described needs, by mixing alumina and silicon nitride in a specific component ratio and then sintering under specific sintering conditions, the thermal spray present in the coexistence form of X-sialon and β-sialon By providing a coating sialon powder and a method of manufacturing the same, and using the coating material as a coating material by thermal spraying or explosion spraying, X-sialon is melted during the spraying process to act as a binder and β-sialon is almost decomposed. The purpose is to obtain a good coating layer because it is not. In addition, by adding a zirconium oxide and titanium oxide alone or a complex additive in addition to the above mixture to prepare a thermal spraying sialon powder for reinforcing the thermal shock resistance and improve the hardness and wear resistance, using this as a coating material The purpose is to provide a spray coating method.

1 is a diagram showing a phase of a Si ₃ N ₄ -AlN-Al ₂ O ₃ -SiO ₂ four-component system.

2 is a pseudo equilibrium diagram of a Si ₃ N ₄ -AlN-Al ₂ O ₃ -SiO ₂ four-component system of the present invention.

FIG. 3 is a diagram illustrating an X-ray diffraction analysis of Comparative Example 2 sintered powder. FIG.

4 is a diagram showing the results of X-ray diffraction analysis of Example 1 sintered powder.

5 is a view showing the results of X-ray diffraction analysis of the coating layer of Preparation Example 1.

6 is a diagram showing an X-ray diffraction analysis result of Example 2 sintered powder.

7 is a view showing the results of X-ray diffraction analysis of the coating layer of Preparation Example 2.

8 is a view showing the results of X-ray diffraction analysis of Example 3 sintered powder.

9 is a view showing the results of X-ray diffraction analysis of the coating layer of Preparation Example 3.

The spray coating sialon powder according to the present invention for achieving the above object is inert to the mixture of alumina (Al ₂ O ₃ ): silicon nitride (Si ₃ N ₄ ) in a weight ratio of 1: 5 to 7: 2. And sintered at a temperature of 1450 to 1800 ° C. under an atmosphere.

In the sialon powder, a mixture of the alumina and silicon nitride as a residual amount is added to 20 to 80% by weight of zirconium oxide (ZrO ₂ ), or the alumina as the residual amount to 5 to 50% by weight of titanium oxide (TiO ₂ ). And a mixture of silicon nitride or a mixture of alumina and silicon nitride as a remainder in a composite additive of 20 to 50% by weight of zirconium oxide (ZrO ₂ ) and 5 to 20% by weight of titanium oxide (TiO ₂ ). It is done.

In the sialon powder, an oxide of at least one element selected from the group consisting of lithium, magnesium, calcium, scandium or yttrium is added in an amount of 1 to 7% by weight based on the total weight.

On the other hand, the method for producing a spray coating sialon powder according to the present invention comprises the steps of mixing alumina (Al ₂ O ₃ ): silicon nitride (Si ₃ N ₄ ) in a weight ratio of 1: 5 to 7: 2; Sintering the mixture at a temperature of 1450-1800 ° C. under an inert atmosphere; And crushing the sintered material.

Further, in the method for producing sialon powder, a mixture of the alumina and silicon nitride as a residual amount is added to 20 to 80% by weight of zirconium oxide (ZrO ₂ ), or the remaining amount to 5 to 50% by weight of titanium oxide (TiO ₂ ). A mixture of the alumina and silicon nitride is added, or a mixture of the alumina and silicon nitride is added to the composite additive of 20 to 50% by weight of zirconium oxide (ZrO ₂ ) and 5 to 20% by weight of titanium oxide (TiO ₂ ). It is characterized in that to manufacture.

In addition, the method for producing sialon powder, characterized in that it is prepared by adding an oxide of at least one element selected from the group consisting of lithium, magnesium, calcium, scandium or yttrium in an amount of 1 to 7% by weight based on the total weight. It is done.

On the other hand, the thermal spray coating method according to the invention is characterized in that the spray coating method to spray the coating material on the matrix by the explosion spray or high-speed flame spray method, using the sialon powder as a coating material.

Hereinafter, the present invention will be described in detail.

In preparing the spray coating sialon powder of the present invention, alumina (Al ₂ O ₃ ) and silicon nitride (Si ₃ N ₄ ) are used as essential components, zirconium oxide (ZrO ₂ ), titanium oxide (TiO ₂ ) is negative. It may be further added as a component, and an oxide of lithium, magnesium, calcium, scandium or yttrium may be further added as an auxiliary component.

The essential components and / or subcomponents and / or auxiliary components are mixed in an appropriate weight percent, followed by sintering at a temperature of 1450 to 1800 ° C. under an inert atmosphere, and then crushed to simultaneously assemble X-sialon and β-sialon. Once formed and subcomponents are added, a sialon powder suitable for spray coating with other phases coexists.

Explosion spraying or high speed flame spraying on the matrix using the sialon powder prepared by the above method as a coating material, the X-sialon is melted during the spraying process to act as a binder, and the β-sialon spray coating layer is left as it is. Are manufactured.

Hereinafter, the operation of the spray coating sialon powder of the present invention according to the configuration and the effect of the spray coating method using the powder will be described in detail.

FIG. 2 shows a quasi-equilibrium phase diagram at 1800 ° C. for a Si ₃ N ₄ -AlN-Al ₂ O ₃ -SiO ₂ four-component system as in FIG. Various images that can be shown are shown. In FIG. 2, the phase denoted by J means J-sialon (hereinafter, referred to as “X-sialon”), and represents the same phase as the X-sialon denoted by X in FIG. 1. The composition of the phase falls in the range of Si ₆ Al ₁₀ O ₂₁ N ₄ and Si ₃ Al ₆ O ₁₂ N ₂ . In general, as shown in the state diagrams of FIGS. 1 and 2, sialon is composed of Al ₂ O ₃ , Si ₃ N ₄ , SiO ₂ , AlN 4-component or Al ₂ O ₃ , Si ₃ N ₄ , AlN 3-component in an appropriate ratio. The mixture is prepared by sintering in an inert atmosphere, but it can also be prepared using only Al ₂ O ₃ and Si ₃ N ₄ two components as in the present invention.

According to Figure 2 by mixing alumina (Al ₂ O ₃ ) and silicon nitride (Si ₃ N ₄ ) in a weight ratio of less than 1: 5 X-sialon is not formed when the amount of Al ₂ O ₃ is insufficient, 7: When the amount of Al ₂ O ₃ becomes excessive by mixing at a weight ratio of more than ₂ , Al ₂ O ₃ phases coexist in addition to X-sialon and β-sialon. Thus, when Al ₂ O ₃ phase is formed in the thermal spray powder Transform into a statue. In the spray coating layer In the presence of a phase, if the temperature is raised to a temperature of 700 ° C. or higher, a phase transformation occurs to the α phase again, thereby causing a volume change to cause cracking or peeling of the coating layer. Thus, there is a problem in that the thermal spray coating layer cannot be used at a high temperature. Therefore, in the preparation of the spray coating sialon powder of the present invention, in order to form a zone where X-sialon and β-sialon coexist, alumina (Al ₂ O ₃ ) and silicon nitride (Si ₃ N ₄ ) are 1: It is preferable to mix in the weight ratio of 5-7: 2. If the weight ratio of Al ₂ O ₃ increases within the above range, the amount of X-sialon increases relatively, and if the weight ratio of Si ₃ N ₄ increases, the amount of β-sialon tends to increase relatively.

In addition, as an sintering condition, an inert atmosphere and an appropriate temperature are required. In general, during sintering, the sintering process is carried out by pressurizing the nitrogen to about 8 to 10 atm, which increases the pressure of the nitrogen, which leads to the formation of more stable nitrides, as well as the volatilization of some of the sintered components. but because of the advantages that can minimize a phenomenon of eroding the refractory material, the experimental results, even if the pressure of the nitrogen to the atmospheric pressure Z = 3 of β- siAlON is Si ₃ Al ₃ O ₃ N _5, and between the X- sialon to the binder role Since it is easily formed, it is not necessary to sinter by pressurizing the pressure of nitrogen, and in the present invention, sintering under an inert atmosphere such as a nitrogen atmosphere is preferable.

In order to spray, the sintered body should be manufactured in powder form. If the sintering temperature is less than 1450 ℃, the strength of the sintered body is weak, so it breaks too fine in the process of crushing the sintered body into powder, and X-sialon Although β-sialon is formed, there is a problem in that it is not formed. The higher the sintering temperature, the more severe the erosion of the refractory. However, when it exceeds 1800 ° C, the quality of the produced sintered body is adversely affected, so that sintering at a temperature of 1450-1800 ° C is preferred. desirable. More preferably, the sintering temperature is a temperature of 1500 to 1700 ℃.

It is sufficient to sinter for 30 minutes or more under the above sintering conditions and it is not necessary to sinter for more than 2 hours.

In addition to alumina (Al ₂ O ₃ ) and silicon nitride (Si ₃ N ₄ ), zirconium oxide (ZrO ₂ ) and titanium oxide (TiO ₂ ) may be selectively added alone or in combination.

The zirconium oxide (ZrO ₂ ) is the most commonly used material at high temperature, and zirconium oxide having a thermal expansion coefficient of 10 × 16 ⁻⁶ / K is added during the production of sialon having a thermal expansion coefficient of 3 to 4 × 16 ⁻⁶ / K. In this case, zirconium oxide does not participate in the reaction to form sialon, but exists as a separate oxide phase, thereby making a composite material in which sialon and zirconium oxide are separately present. The composite material of sialon + zirconium oxide obtained at this time has a coefficient of thermal expansion that is about half that of sialon and zirconium oxide. Therefore, in forming the sialon coating layer, forming the metal base material / ZrO ₂ coating layer / (sialon + ZrO ₂ ) composite coating layer / sialon coating layer stepwise mitigates the thermal shock caused by the difference in thermal expansion coefficient between the base material and the sialon coating layer. Since the peeling of the coating layer does not easily occur during cooling, it can be used for a long time even at high temperature. When added in an amount of less than 20% by weight of the ZrO ₂ to the total mixture the total weight, because an increase of thermal expansion coefficient truly effective, and 80% by weight, the addition in an amount of more than ZrO ₂ substantially similar to the coefficient of thermal expansion of the sole, ZrO ₂ Is preferably added in an amount of 20 to 80% by weight, based on the total weight of the mixture. The ZrO ₂ may be added alone or in combination with the following titanium oxide (TiO ₂ ), and the remaining amount except for this alone or composites may be alumina (Al ₂ O ₃ ), silicon nitride (Si ₃ N ₄ ), and / or lithium, An oxide of at least one element selected from the group consisting of magnesium, calcium, scandium or yttrium is occupied.

Meanwhile, the titanium oxide (TiO ₂ ) is reacted with nitrogen in an inert atmosphere to form TiN. When TiO ₂ is added in the preparation of the thermal spray powder, a composite of (X-sialon + β-sialon + TiN) can be finally formed to increase the hardness and wear resistance of the coating layer. When TiO ₂ is added in an amount of less than 5% by weight based on the total weight of the mixture, the hardness or abrasion resistance is hardly improved.When the amount of TiO ₂ is added in an amount of more than 50% by weight, the amount of X-sialon is small, resulting in a dense coating layer structure. Difficult to obtain Therefore, TiO ₂ is preferably added in an amount of 5 to 50% by weight based on the total weight of the mixture.

Meanwhile, in addition to the alumina (Al ₂ O ₃ ) and silicon nitride (Si ₃ N ₄ ), the zirconium oxide (ZrO ₂ ) and titanium oxide (TiO ₂ ) may be added in combination, and zirconium oxide (ZrO ₂ ) is 20 to 50% by weight of titanium oxide (TiO ₂₎ is 5 to 20% by weight when the oxidation mixture so weak a coating layer delamination and increases the hardness and abrasion resistance of the coating layer of zirconium (ZrO ₂₎ 20~50% by weight of titanium oxide (TiO ₂ ) It is preferable to use a composite additive with 5 to 20% by weight. The use of smaller amounts of zirconium oxide or titanium oxide has little effect of increasing the coefficient of thermal expansion or little increase in hardness and abrasion resistance. The use of more excess zirconium oxide or titanium oxide does not alleviate thermal shock or make it difficult to obtain a dense coating structure. have.

In addition, one or more selected from the group consisting of lithium, magnesium, calcium, scandium or yttrium, in addition to alumina (Al ₂ O ₃ ), silicon nitride (Si ₃ N ₄ ), zirconium oxide (ZrO ₂ ) and titanium oxide (TiO ₂ ) Oxides of the elements may optionally be added.

The oxide of lithium, magnesium, calcium, scandium or yttrium lowers the melting point of X-sialon, which acts as a binder in the present invention, so that it melts well during the thermal spraying process, so that the structure of the coating layer is dense or the real rate of powder ("feeding powder"). Ratio of the amount of the powder forming the coating layer to the amount "means Deposition Efficiency). When the oxide is added in an amount of less than 1% by weight based on the total weight of the mixture, it hardly lowers the melting point of X-sialon, and when it is added in an amount of more than 7% by weight, the characteristics of the coating layer at high temperatures are deteriorated. The oxide of at least one element selected from the group consisting of lithium, magnesium, calcium, scandium or yttrium is preferably added in an amount of 1 to 7% by weight based on the total weight of the mixture.

It is possible to produce a spray coating sialon powder in which X-sialon and β-sialon coexist under the above-described components, component ratios, and sintering conditions.

On the other hand, by using the sialon powder prepared by the above-described method by explosion spraying or high-speed flame spraying according to a conventional method, X-sialon is melted to act as a binder to prepare a spray coating layer coated β-sialon Can be. This is because the X-sialon has a lower melting point than β-sialon and thus melts in the flame to act as a binder, and β-sialon remains in the coating layer without being decomposed in the flame.

Although an Example and a comparative example are given to the following and this invention is demonstrated to it further more concretely, this invention is not limited only to these examples.

Example 1

180 g of alumina (Al ₂ O ₃ ) having a size of 0.3 μm and 130 g of silicon nitride (Si ₃ N ₄ ) having a size of 1 μm were mixed, and then sintered at a temperature of 1550 ° C. under nitrogen atmosphere for 1 hour, and then crushed to 20 to 75. It was made of a sintered powder having a size of μm.

Example 2

117 g of 0.3 μm alumina (Al ₂ O ₃ ), 127 g of silicon nitride (Si ₃ N ₄ ) of 1 μm, 123 g of zirconium oxide (ZrO ₂ ) of 1 μm, 33 g of titanium oxide (TiO ₂ ) of 1 μm After mixing the mixture was sintered for 1 hour at a temperature of 1600 ℃ under nitrogen at 1 atmosphere and then crushed to prepare a sintered powder of 20 ~ 75㎛ size.

Example 3

182 g of 0.3 μm alumina (Al ₂ O ₃ ), 133 g of 1 μm silicon nitride (Si ₃ N ₄ ), 59 g of titanium oxide (TiO ₂ ) of 1 μm, and 26 g of magnesium oxide (MgO) of 1 μm After mixing, the mixture was sintered for 1 hour at a temperature of 1550 ° C. under nitrogen atmosphere and then crushed to prepare a sintered powder having a size of 20 to 75 μm.

Comparative Example 1

180 g of alumina (Al ₂ O ₃ ) having a size of 0.3 μm and 130 g of silicon nitride (Si ₃ N ₄ ) having a size of 1 μm were mixed, sintered at a temperature of 1400 ° C. under vacuum atmosphere for 1 hour, and then crushed to 20 to 75 μm. It was made of sintered powder of size.

Comparative Example 2

180 g of alumina (Al ₂ O ₃ ) having a size of 0.3 μm and 130 g of silicon nitride (Si ₃ N ₄ ) having a size of 1 μm are mixed, and then sintered at a temperature of 1400 ° C. under nitrogen atmosphere for 1 hour, and then crushed to 20 to 75. It was made of a sintered powder having a size of μm.

4, 6 and 8 show the results obtained by X-ray diffraction analysis of the sintered compacts of Examples 1 to 3, and FIG. 3 shows the results obtained by X-ray diffraction analysis of the sintered compact of Comparative Example 2 Is shown.

As shown in Figure 4, the sintered compact powder of Example 1 can be seen that the X-sialon and β-sialon coexist, the other peaks do not appear to be the most alumina (Al ₂ O ₃ ) and silicon nitride (Si ₃ N ₄ ) were used for the sialon formation reaction.

In addition, as shown in FIG. 6, X-sialon and β-sialon coexist in the sintered compact of Example 2 as in FIG. 4, and other ZrO ₂ present The m-ZrO ₂ peak, which is a monolithic phase peak, the t-ZrO ₂ peak, which is a tetragonal phase peak, and the T peak, which is a peak of TiN formed by nitriding during TiO ₂ sintering, appeared.

In addition, as shown in Figure 8, the sintered compact powder of Example 3 can be seen that the X-sialon and β-sialon coexist in the same manner as in Figure 4, the other T peak Increasing the content of TiO ₂ was much larger than the T peak of FIG.

Meanwhile, as shown in FIG. 3, it can be seen that X-sialon is formed in the sintered compact powder of Comparative Example 2, but β-sialon is not formed. In addition, although not shown, the sintered compact of Comparative Example 1 did not generate a sialon reaction, and only peaks of alumina (Al ₂ O ₃ ) and silicon nitride (Si ₃ N ₄ ), which are raw powders, appeared.

On the other hand, the microhardness of the sintered compact powders of Examples 1 to 3 and Comparative Examples 1 and 2 using the MVH (Micro Vickers Hardness) hardness tester is shown in Table 1 below. At this time, the load was 300 g.

Microhardness (Unit: HV 300g) Example 1 580 Example 2 600 Example 3 650 Comparative Example 1 550 Comparative Example 2 530

As can be seen in Table 1, the more the amount of titanium oxide (TiO ₂ ) is added tends to increase the microhardness.

Hereinafter, the present invention will be described in more detail with reference to production examples, but the present invention is not limited only to these examples.

[Production Example 1]

A spray coating layer was prepared by using a sintered compact of Example 1 having a size of 20 to 75 μm as a coating material by thermal spraying or high speed flame spraying according to a conventional method.

[Production Example 2]

A spray coating layer was prepared by using a sintered compact of Example 2 having a size of 20 to 75 μm as a coating material by thermal spraying or high speed flame spraying according to a conventional method.

[Manufacture example 3]

A spray coating layer was prepared by using a sintered compact of Example 3 having a size of 20 to 75 μm as a coating material by explosion spraying or high speed flame spraying according to a conventional method.

Meanwhile, the results obtained by X-ray diffraction analysis of the coating layers of Preparation Examples 1 to 3 are shown in FIGS. 5, 7 and 9.

As shown in FIG. 5, the coating layer of Preparation Example 1 did not show an X-sialon peak present in the sintered compact powder of FIG. 4, and only a β-sialon peak was clearly visible, and a peak near 30 ° was convex. It can be seen that the X-sialon melted in the flame and quenched as it collided with the base metal to form a glass phase.

In addition, as shown in FIG. 7, the coating layer of Preparation Example 2 did not show the X-sialon peak present in the sintered compact powder of FIG. 6, and only the β-sialon peak was clearly seen. On the other hand, ZrO ₂ present in phase transformation occurred during the thermal spraying process, whereas the tetragonal phase peak t-ZrO ₂ peak predominantly in contrast to the sintered powder, and the monolithic phase m-ZrO ₂ peak decreased relatively. In addition, it can be seen that the TiN formed in the powder is included in the coating layer as it is almost not decomposed during the spraying process.

In addition, as shown in FIG. 9, the X-sialon peak present in the sintered compact powder of FIG. 8 was not formed in the coating layer of Preparation Example 3, and only β-sialon peaks were clearly seen. In addition, it can be seen that the TiN formed in the powder was further increased in the coating layer.

As can be seen from the above, X-sialon is melted during the thermal spraying process by preparing a spray coating sialon sintered powder for spray coating of the present invention and spray coating by using a thermal spraying or high speed flame spraying as a coating material The β-sialon is hardly decomposed to obtain a good coating layer, and the thermal shock resistance is reinforced by spray coating the sintered body powder prepared by adding zirconium oxide and titanium oxide alone or in combination to the mixture as a coating material. Since it improves the hardness and wear resistance there is an advantage that can be widely used for industrial purposes.

Claims (12)

Alumina (Al ₂ O ₃ ): silicon nitride (Si ₃ N ₄ ) in a weight ratio of 1: 5-7: 2, the mixture is sintered at a temperature of 1450 ~ 1800 ℃ under an inert atmosphere and then crushed Sialon powder for spray coating. The method of claim 1, 20 to 80% by weight of zirconium oxide (ZrO ₂ ) is added to the mixture as a residual amount sialon powder for thermal spray coating. The method of claim 1, A sialon powder for thermal spray coating comprising adding the mixture as a residual amount to 5 to 50% by weight of titanium oxide (TiO ₂ ). The method of claim 1, A sialon powder for thermal spray coating, characterized in that the mixture is added as a remainder to a composite additive of 20 to 50% by weight of zirconium oxide (ZrO ₂ ) and 5 to 20% by weight of titanium oxide (TiO ₂ ). The method according to any one of claims 1 to 4, A sialon powder for thermal spray coating, characterized in that an oxide of at least one element selected from the group consisting of lithium, magnesium, calcium, scandium or yttrium is added in an amount of 1 to 7% by weight based on the total weight. Mixing alumina (Al ₂ O ₃ ): silicon nitride (Si ₃ N ₄ ) in a weight ratio of 1: 5 to 7: 2; Sintering the mixture at a temperature of 1450-1800 ° C. under an inert atmosphere; And Method for producing a spray coating sialon powder, characterized in that comprising the step of crushing the sintered product. The method of claim 6, Method for producing a spray coating sialon powder, characterized in that for adding the mixture as a residual amount to 20 to 80% by weight of zirconium oxide (ZrO ₂ ) in the mixing step. The method of claim 6, Method for producing a spray coating sialon powder, characterized in that the addition of the mixture as a residual amount to 5 to 50% by weight of titanium oxide (TiO ₂ ) in the mixing step. The method of claim 6, A method for producing a sialon powder for thermal spray coating, characterized in that the mixture is added as a remainder to a composite additive of 20 to 50% by weight of zirconium oxide (ZrO ₂ ) and 5 to 20% by weight of titanium oxide (TiO ₂ ). The method according to any one of claims 6 to 9, A method for producing a spray coating sialon powder, characterized in that for adding an oxide of at least one element selected from the group consisting of lithium, magnesium, calcium, scandium or yttrium in an amount of 1 to 7% by weight based on the total weight. In the thermal spray coating method for spraying the coating material on the matrix by the explosion spray or high-speed flame spray method, Spray coating method characterized in that to use the sialon powder of any one of claims 1 to 4 as the coating material. In the thermal spray coating method for spraying the coating material on the matrix by the explosion spray or high-speed flame spray method, Spray coating method characterized in that to use the sialon powder of claim 5 as the coating material.