KR20130113941A - Object produced by thermal spraying and method of thermal spraying therefor - Google Patents

Abstract

An object of the present invention is to prolong the life of a thermal sprayed coating sprayed on a molten metal member and to prevent adhesion of molten metal. MEANS TO SOLVE THE PROBLEM In order to solve the said subject, according to this invention, the thermal spray coating is a molten metal member which covered the contact site which contact | connects the molten metal containing Zn and / or Al with the thermal spray coating, The average particle diameter is made into the median diameter. By using the oxide-based ceramic thermal sprayed particles having a particle size of 10 μm or less, the thermal sprayed particles are formed by spraying at a high-speed flying particle speed of 1000 m / sec or more while the surface is semi-melt while the inside is solid, and the corrosion resistance to molten metal, It is characterized by increasing insulation, corrosion resistance to acid washing, and prevention of adhesion of molten metal.

Description

OBJECT PRODUCED BY THERMAL SPRAYING AND METHOD OF THERMAL SPRAYING THEREFOR}

The present invention relates to a target to be sprayed onto the sprayed particles and a method for producing the target.

As a method of forming a film on the surface of a steel plate, the method of immersing a steel plate in the pool in which molten metals, such as zinc, aluminum, a zinc-aluminum alloy, were accommodated is known. The transfer roll which conveys a steel plate is provided in this pool, and there exists a possibility that this conveyance roll may penetrate and corrode with molten metal. Therefore, as a countermeasure against penetration corrosion, the method of covering the surface of a conveyance roll with a protective film is known.

As a method of forming a protective film of this kind, a high speed gas spraying method is known. Patent documents 1 and 2 disclose the method of thermally spraying a WC-Co type | system | group or a WC-B-Co type | system | group cement material by the high speed gas spraying method. Patent document 3 discloses the method of performing a hole sealing process to the sprayed layer formed by plasma-spraying ceramics, such as chromia, on this film. Patent document 4 discloses the method of producing a chromium carbide and hole-sealing by the surface and the pore part of a sprayed layer. Patent document 5 discloses a method of thermally spraying a composite ceramic made of SiO ₂ -Cr ₂ O ₃ -Al ₂ O ₃ on a surface of a substrate with a plasma gun or a gas spray gun, and sealing the hole with Cr oxide. . Patent document 6 discloses a method in which the difference between the immersion potentials is 80 kPa or less by adjusting the components of the binder as a countermeasure to prevent localization of WC and Co in the thermal sprayed cement and forming a local battery in molten zinc. .

JPS48-11237 A JP 2553937 B JPH5-209259 A JPH8-109458 A JP 2002-4016 A JP 2009-19271 A

However, in the thermal spraying method and hole sealing treatment described in Patent Documents 3 to 5, the bonding force between the ceramic particles is weak, the porosity is high, and the porosity is high. .

Even in the method described in Patent Document 6, it is impossible to set the corrosion potential to zero, and the promotion of dissolution loss cannot be prevented.

Therefore, an object of this invention is to provide the to-be-injected body provided with the oxide ceramic thermal sprayed coating which is strong, the density | concentration is small, there is little alteration, and insulation is high.

In order to solve the above problems, the object to be sprayed according to the present invention uses an oxide-based ceramic sprayed particles having an average particle diameter of 10 μm or less as a median diameter, and is compact, deteriorated and highly insulating oxide-based ceramics. Have a warrior coat. Here, an average particle diameter is a median diameter measured by the laser diffraction scattering measurement method.

According to the present invention, it is possible to provide a sprayed object having a strong and dense bonding force between the sprayed particles, which has little alteration and has an insulating ceramic sprayed coating having high insulation.

1 is a cross-sectional optical micrograph of a conventional WC-B-Co-based cement high-speed gas spray coating immersed in molten metal of 55 wt% aluminum / 45 wt% zinc of 873K for 16 days;
2 is an optical micrograph of a film in which oxide-based ceramics (chromia) are thermally sprayed on a WC-B-Co-based cement high-speed gas thermal spray coating according to Patent Document 3;
Fig. 3 shows a hole unsealed film sprayed by a high speed gas sprayer using a 6 μm finely divided gray alumina thermal sprayed particles using a high speed gas sprayer on a cement sprayed film sprayed with a high speed gas spraying device. Optical photomicrograph of cross section of test piece immersed in molten metal of 55 wt% aluminum / 45 wt% zinc for 16 days
4 is a sectional view of a high speed gas spray device;
5 is a cross-sectional view of a high speed gas spraying apparatus of JP2009-179846A;
6 is a schematic view of a blast wear test apparatus.

The to-be-sprayed body of this invention contains the various member which the oxide ceramic sprayed coating which is excellent in the bonding force between the spray particles, is compact, there is little alteration, and high insulation is needed. Such a member includes a member in contact with the molten metal, a conveying roller for conveying a high temperature glass of 473 K or more, and a hearth roll disposed in a heat treatment furnace of a steel sheet.

In the member which contacts molten metal, the conveyance roll which conveys a steel plate in the storage container in which the molten metal for steel plate plating was stored, the conveyance roll which conveys the steel plate with molten metal from the exterior of a storage container, and a molten metal flow in The conveying pump which conveys a mold, the ladle used for a mold, and a molten metal is included.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment is described in detail using the member which contacts molten metal as an example.

As a property required for the thermal spray coating sprayed on the molten metal member, such as a conveyance roll used for hot-dip galvanizing, as described in patent documents 4 and 6, (1) erosion by molten zinc hardly occurs, (2 ) It is hard to wear even when it comes into contact with stripe (steel plate), (3) Easy peeling and maintenance inspection of attached molten zinc, (4) Long life and low cost as plating member, (5) Hot melting It is required to withstand thermal shock when immersed in zinc, (6) low corrosion potential in components of cement spray coating in molten zinc.

However, the thermal spray coating which sprayed the cement material of WC-Co type | system | group or WC-B-Co type | system | group of patent documents 1 and 2 by the high-speed gas spraying method is a Co-binder is eroded by molten zinc and aluminum, and through a through pore and a pore, These molten metals penetrate and corrode the thermal spray coating, and at the same time, a corrosion potential is generated and the thermal spray coating is peeled off and worn out. Moreover, the molten metal which permeated the sprayed coating will become stuck in the sprayed coating, and it will not peel easily, but will reduce the plating quality of a steel plate.

The coating of thermally sprayed oxide ceramics on the cement spray coatings described in Patent Literatures 3 to 5 is easily cracked and peeled off due to thermal shock, and has a low film strength and abrasion resistance. . However, since the bonding structure is fragile, mechanical external force and thermal stress act, so that cracking and peeling easily occur, and insulation is low. Also, since the ceramic thermal sprayed coating is a pumice-like structure in which pores and through pores of about 15% to 25% exist, molten metal easily penetrates into pores and through pores of the ceramic thermal sprayed coating, and the molten metal and its oxide (Dross) becomes a state in which the thermal spray coating is lodged, and is not easily peeled off, which degrades the plating quality of the steel sheet.

Background Art In recent years, on the background of cost reduction and improvement in production efficiency, further longer life of the conveying roll is required, and the quality of the plated steel sheet is advanced, and the molten metal and the oxide thereof adhered to the conveying roll ( As a countermeasure against plating quality defects by dross), the ease of peeling of molten metals and their oxides is strongly demanded.

In addition, since the conveyance rolls are reused by dissolving zinc and aluminum adhered by washing with acids such as sulfuric acid and hydrochloric acid, the lifespan of acid corrosion is required.

This inventor analyzed the conventional thermal spray coating, and analyzed the cause which a thermal spray coating peeled and was damaged. FIG. 1 is a photograph taken with an optical microscope of a cross section of a conventional WC-B-Co-based cement high-speed gas spray coating, which was immersed in a molten metal of 55 wt% aluminum / 45 wt% zinc of 873K for 16 days. Zinc and aluminum which are molten metal components penetrate into a thermal spray coating, and a crack arises in a thermal spray coating, and it exists just before peeling. Co, which is a binder of the thermal spray coating, corrodes and infiltrates the molten metal, and the molten metal is infiltrated and corroded through the through pores and pores.

FIG. 2 is a photograph of a cross section of a film sprayed with oxide ceramics (chromia) on a WC-B-Co-based cement high-speed gas thermal spray coating according to Patent Document 3; Ceramics are usually thermally sprayed using a plasma gun because of their high melting point. Since the plasma temperature of the plasma gun is about 30,000 K, the sprayed particles are completely melted and become a volume to impinge on the substrate, but the sprayed particles have a low velocity of about 250 m / sec, so that 15% to 25% of pores exist in the sprayed coating. However, although the bonding force between the sprayed particles is low and the hole sealing treatment material is connected between the sprayed particles, it is not possible to fill all the pores, and the ceramic oxide itself does not react with the molten metal, but the molten metal is embedded in the pores to peel off the molten metal. Disturbing. In addition, cracks and peelings occur in the hole sealant due to mechanical external force and thermal stress caused by contact with the steel sheet, whereby molten metal is further embedded therein to make the molten metal more difficult to peel off.

In addition, since plasma-sprayed oxide-based ceramic particles are quenched from a volume state, many fine cracks are present, resulting in a decrease in mechanical strength and deterioration in insulation.

MEANS TO SOLVE THE PROBLEM When an oxide-type ceramic sprayed coating with a low density and high insulation with a high density of interparticle bonding is realized, this inventor has favorable peelability of zinc, prevents generation of a corrosion potential, and prevents acid penetration and acid washes. It was found that a long-life soldering metal member of wear-resistant and corrosion-resistant metal corrosion resistant to the repetition of.

The thermal spray coating used for the molten metal member receives a large thermal shock upon contact with the molten metal. In the ceramic thermal spraying material which is inferior in toughness compared with metal and cement thermal spraying material, the method which conventionally employ | adopted the method which relieve thermal stress to thermal deformation as a structure by making pore-formed organization of pumice-shaped shape. On the other hand, since the plasma temperature of the plasma gun is about 30,000K, the sprayed particles are completely melted and become a volume and collide with the substrate, but the sprayed particle velocity is low at about 250m / sec, so that 15% to 25% of pores are inevitably in the sprayed coating. exist. In addition, the ceramics, once dissolved and thermally sprayed, are phase-changed and deteriorated, so that they are similar to the original ceramics as bulk bodies, but are different.

MEANS TO SOLVE THE PROBLEM This inventor is an injectable body excellent in the thermal shock property which has a thermal sprayed coating sprayed by the oxide type ceramics thermal sprayed particle whose average particle diameter is 10 micrometers or less in a median diameter, and the said thermal sprayed particle in the said thermal sprayed coating was once heat-melted. Then, the target object contacted with the solidified surface layer part and the molten metal formed by the inner layer part which was not heat-melted at the time of spraying was found.

4 is a cross-sectional view of the high speed gas spraying device. The thermal spray coating is thermally sprayed by the high speed gas thermal spraying apparatus shown in FIG. 4. Kerosene or kerosene, which is a fuel filled in the combustion chamber 2, is burned with high pressure oxygen, and the combustion chamber is at a high pressure of about 0.7 MPa. Combustion gas is produced | generated by the high temperature and supersonic gas of 3270K, about 3000m / sec by the Laval nozzle 3 provided in the combustion chamber exit. The sprayed particles sprayed from the sprayed-particle spray nozzle 4 are supplied here. The sprayed sprayed particles are heated and accelerated to be sprayed onto the sprayed material.

The structure of the high speed gas spraying machine shown in FIG. 4 is demonstrated in detail. This high-speed gas spraying machine is divided into a combustion chamber tail plug 1 disposed at a rear end, a combustion chamber 2 in front of the spraying direction, and a thermal spray nozzle 5 connected to the combustion chamber 2. It is.

The combustion chamber tail plug 1 has a fuel supply hole 7 for supplying fuel such as kerosene or kerosene at high speed in the spraying direction and an oxygen supply hole for supplying oxygen gas at high speed in the spraying direction ( 8) is arranged.

The combustion chamber 2 with the combustion chamber tail stopper 1 is formed in the shape of a cylinder, and is connected to the thermal spray nozzle 5 in a shape in which the diameter of the combustion chamber 2 is narrowed and then gradually widened. Is formed.

The thermal spray nozzle 5 connected through the combustion chamber 2 and the laval nozzle 3 is a copper pipe which has an internal diameter of about 11 mm and has a length of about 10 cm-20 cm, and is cooled by water from the outside. The thermal spray material supply part 4 which supplies a thermal spray material is arrange | positioned at the laval nozzle 3 side of the thermal spray nozzle 5. As a thermal spraying material, the material which added Ni, Ni-Cr type, or Co type alloy to the material which suited the required characteristic, such as abrasion resistance, is used.

When spraying, the kerosene or kerosene supply hole 7 and the oxygen supply hole 8 provided in the combustion chamber tail stopper 1 are first burned in the combustion chamber 2. At this time, the combustion gas in the combustion chamber 2 has a pressure of about 0.7 MPa and a combustion temperature of about 3000 ° C. Then, the combustion gas is sent to the Laval nozzle, accelerated from the sound speed to the supersonic speed when passing through the Laval nozzle 3, and is supplied to the thermal spray nozzle (5). And at the connection part of the laval nozzle 3 and the thermal spray nozzle 5, the thermal spray material is injected from the thermal spray material supply part 4 with respect to the accelerated combustion gas. The thermal spray material is accelerated by the combustion gases and simultaneously heated. The combustion gas and the thermal spraying material are rectified by passing through the thermal spraying nozzle 5 to increase convergence and are injected from the tip of the thermal spraying nozzle 5. Thereby, the thermal spraying material can be sprayed at a very high speed and the thermal sprayed material can be sprayed onto the thermal sprayed material.

Although the thermal spray test was carried out to the high speed gas spraying apparatus of FIG. 4 by spraying white alumina which is an oxide type ceramics with an average particle diameter of 40 micrometers as a median diameter, the thermal spraying test was not carried out at all.

Therefore, the surface temperature of the thermal sprayed particles measured at 2053K and the thermal sprayed particles velocity of 815 m / sec were measured using an Accuraspray thermal spray measuring apparatus manufactured by Sulzer Metco. On the other hand, the melting point of white alumina was 2302K, and it turned out that it was not formed due to lack of temperature and speed.

If the sprayed particles are assumed to be perfect spheres, the surface area is proportional to the square of the diameter and the volume is proportional to the third power of the diameter. Therefore, the specific surface area becomes large in inverse proportion to the diameter. For example, when the sprayed particle diameter is reduced from 40 µm to 4 µm, the specific surface area increases by 10 times. The weight is 1/1000. Since the sprayed particles injected into the combustion gas are heated on the surface and injected through the flow of the combustion gas, it is expected that the temperature and speed of the sprayed particles increase when the sprayed particles are made fine.

White alumina particles having an average particle diameter of 4 µm as the median diameter were sprayed and measured using an Accuraspray thermal spraying device manufactured by Sulzer Metco. The surface temperature of the thermal sprayed particles was 2700 K, and the thermal spray particles had a speed of 2750 m / sec. This exceeded 2302K of melting | fusing point of white alumina, and actually sprayed, and it formed 6 micrometers per 1 pass. When the film was x-ray diffracted, the film remained in the α phase, which is the bulk material of white alumina, and it was confirmed that the γ phase produced when molten was only a part, and the physical properties of the film were very close to the bulk material of the white alumina.

White alumina particles having an average particle diameter of 10 µm as the median diameter were sprayed and measured using a Accuraspray thermal spraying device manufactured by Sulzer Metco, and the surface temperature of the thermal sprayed particles was 2400K and the thermal spray particle speed was 1000 m / sec. This exceeded 2302K of melting | fusing point of white alumina, and actually sprayed, and it formed 1 micrometer per pass.

By using an oxide-based ceramic sprayed particle having an average particle diameter of 10 μm or less as a median diameter, and spraying the sprayed particles at a high-flying particle speed of 1000 m / sec or more while the sprayed particles are in a semi-melt state while the surface is in a solid state, The spraying of the oxide type ceramics which was considered not to form into a film was discovered by the high speed gas spraying apparatus.

On the other hand, in the conventional high-speed gas spraying device, although spraying can be performed for a short time, the thermal spraying defects called spitting are formed because the thermal sprayed particles adhere to and peel off the inner surface of the nozzle 5. Occurred.

5 is an example of the high speed gas spraying apparatus of JP 2009-179846A by the present inventor, and is provided at the tip of the high speed gas spraying apparatus 1. The inner diameter of the inner cylinder 2 is the same diameter as the inner diameter of the nozzle of a high speed gas spraying apparatus. Air, nitrogen gas, or the like injected from the gas injection hole 4 is injected from a cylindrical gap with the outer cylinder 3 to form a cylindrical gas tunnel, thereby preventing the oxidation of the thermal sprayed particles. On the other hand, it is not necessary to use when spraying oxide ceramics. The fine-spray spray particles are injected from the thermal spray powder injection section 5 into the center and inside the combustion gas 6 at high temperature and high speed, and are at high temperature and high speed.

When the oxide-based ceramics were thermally sprayed using the high speed gas spraying apparatus of FIG. 5, nozzle wear and spitting did not occur, and thus the thermal spraying was performed stably.

Oxide-based ceramic thermal sprayed particles injected into the high-speed gas spraying apparatus with a fine particle having an average particle diameter of 10 µm or less as a median diameter are heated and accelerated at a surface temperature and a speed close to the combustion gas of the high-speed gas thermal spraying apparatus. Since the distance from the thermal sprayer to the sprayed material (200 mm in this test example) is short and the heating time is short, the oxide-based ceramic thermal sprayed particles in flight are semi-molten and the solid inside. In this case, the workpiece is impacted at a supersonic speed of 1000 m / sec or more. As a result, unlike the thermal spray coating of the oxide ceramics by the conventional plasma gun, it is dense and becomes an insulating thermal spray coating with very little alteration with high interparticle bonding force. In addition, since high compressive residual stress remains in the thermal spray coating, it exhibits high intergranular bonding force, mechanical external force, crack resistance due to thermal shock, and peeling resistance. That is, the thermal sprayed particle which collided with the to-be-sprayed material has the surface layer part which solidified after thermal spraying of the thermal sprayed particle, and the inner layer part before the thermal spraying particle is injected into a high speed gas spraying apparatus without thermal melting. By spraying this surface layer part firmly with the surface layer part of the adjacent sprayed particle | grains without a clearance, the sprayed coating provided with the said characteristic can be obtained. In addition, the hole sealing process is conventionally required, and in the example of the roll used in a zinc bath, although spraying was one day, four days were required for hole sealing and heat processing. In the present invention, since the hole sealing becomes unnecessary, there is a great effect on cost and air.

Fig. 3 shows a hole-unsealed film sprayed by a high speed gas sprayer using a 6 μm finely divided gray alumina sprayed particles on a Mo-Co and Cr-based cement sprayed film sprayed using a high speed gas spray device. It is an optical micrograph of the test piece cross section immersed for 16 days in molten metal of 873K 55% aluminum / 45% zinc zinc. The fine powder gray alumina thermal spray coating layer was dense, and adhesion of the molten metal was not seen. Moreover, the fine powder gray alumina layer of the surface protected the cement spray coating of the lower layer, and the cement spray coating was also completely sound. Although the test piece was immersed in sulfuric acid for 12 hours and subjected to an acid resistance test, both the finely divided gray alumina coating on the surface layer and the cement spray coating on the lower layer were completely sound, showing excellent properties as a molten metal member. As a result, even if the oxide-based ceramic thermal spray coating for molten metal subjected to thermal shock is not formed as a pumice-shaped multiporosity structure, it is compact, and it can be put to practical use as an oxide-based ceramic thermal spray coating with little alteration due to high interparticle bonding force and high insulation. It turned out to be.

EMBODIMENT OF THE INVENTION Based on the above knowledge, embodiment of this invention is described in detail.

(Embodiment 1)

(1) A sprayed body having excellent thermal shock resistance having a sprayed coating sprayed by an oxide-based ceramic sprayed particles having an average particle diameter of 10 µm or less as a median diameter, wherein the sprayed particles in the sprayed coating are once hot melted. It is formed by the solidified surface layer portion and the inner layer portion which is not thermally melted during thermal spraying.

Oxide-based ceramics are stable because they are oxides, and have excellent characteristics such as abrasion resistance, corrosion resistance at high temperatures, corrosion resistance to acids, heat insulation, insulation, and the like, and are used in molten metals containing Zn and / or Al that are not used in a reducing atmosphere. It can withstand long-term use as the solvent-resistant metal member in contact. Moreover, this invention is not limited to the molten metal containing Zn and / or Al, It can use also in high temperature glass of 473K or more.

(Embodiment 2)

(2) In the structure of said (1), it is preferable that the film thickness of the said oxide type ceramic film is 50 micrometers or less.

Conventional thermal spray particles had a mean particle diameter of about 40 μm as a median diameter, and thus required a film thickness of 200 μm, which is 5 times the minimum particle diameter, to prevent through pores reaching the substrate, but the average particle of the present invention was used. In a dense, highly insulating coating having a diameter of 10 µm or less as the median diameter, even if the spraying thickness is 50 µm or less, its performance is exhibited and the cost is greatly reduced.

(Embodiment 3)

(3) In the configuration of (1) or (2), the base thermal sprayed coating includes a base thermal sprayed coating made of a cement or metal thermal sprayed coating as a base thermal sprayed coating of the oxide ceramic sprayed coating, and has a film thickness of 200 µm or less. Is preferably set to.

Table 1 shows the thermal expansion coefficients of various materials. Generally, in the molten zinc bath, cracks due to thermal expansion difference do not occur when the difference in thermal expansion rate is about 60%, but when it exceeds 60%, cracks are likely to occur. Oxide-based ceramics used for the upper layer generally have a low coefficient of thermal expansion, while stainless used as a substrate has a high coefficient of thermal expansion. Therefore, the crack by the thermal expansion difference can be prevented by performing the thermal spraying which the thermal expansion coefficient is intermediate between both a base material and an upper layer.

When spraying gray alumina, if the base material is SUS316L of austenitic stainless steel, it is preferable to perform metal spraying by STELITE # 6 and WC-B-Co cement spraying on the base.

In the configuration of (1), gray alumina or white alumina can be used as the thermal spray particles. In this case, the thermal spraying particle in the thermal sprayed coating is a γ phase in which the crystal structure of the surface layer portion is changed from the α phase due to thermal melting, and the crystal structure of the inner layer portion is α phase.

material Thermal expansion Remarks Upper layer
Gray alumina 7.4 × 10 ^-6 / K Oxide ceramics White alumina 8.0 × 10 ^-6 / K Oxide ceramics substratum

WC-B-Co series 9.3 × 10 ^-6 / K Cement Mo-Co, Cr-B system 9.2 × 10 ^-6 / K Cement STELITE # 6 15.0 × 10 ^-6 / K Metal system materials

SUS316L 19.3 × 10 ^-6 / K Austenitic SUS SUS410 11.7 × 10 ^-6 / K Martensitic SUS SUS430 11.9 × 10 ^-6 / K Ferritic Stainless Steel

As shown in Table 3, although there are many oxide ceramics, gray alumina is manufactured by melting and reducing natural bauxite directly in an arc electric furnace, so that it has a low melting point, easy spraying, and impact resistance, abrasion resistance, Solvent metallurgical, acid resistance, and molten metal peeling property were good, and as shown in the optical micrograph of FIG. 3, no damage was observed even when immersed in molten metal of 55 wt% aluminum / 45 wt% zinc of 873K for 16 days.

FIG. 6 shows a specimen 1 in which gray conventional alumina particles having a particle size of 25 μm in the median diameter are sprayed with a plasma gun, and a gray alumina in which the average particle diameter of the present application is 6 μm in the median diameter using the blast wear test apparatus of FIG. 6. The bonding force between the thermal spray particles in the thermal sprayed coating was compared with respect to the test piece 2 sprayed with the high speed gas spraying apparatus of 5. Alumina blasting material of # 70 was sprayed at 1 kg at an angle of 60 ° and a distance of 65 mm to measure and compare the loss weight of the thermal sprayed coating. By colliding a blast material from an angle of 60 degrees, between the thermal spray particles in a thermal sprayed coating is peeled off and deteriorated. It is possible to compare the binding force between the particles by comparing the amount of loss. As shown in Table 2, it turned out that the test piece 2 of this invention has a high 5.6 times the particle-to-particle binding force with respect to the test piece 1 of the conventional thermal sprayed coating. It is estimated that Test Piece 1 contained 21% of pores and did not physically bind, and also dissolves the thermal spray particles completely in a plasma of about 30,000 K, thereby contributing to deterioration. have.

Item Test piece 1
Conventional spray coating Test piece 2
Invention Warrior Plasma gun
Sulzer Metco 10MB Gun High speed gas spray device
5 Thermal spray particle size 25 μm 6 μm Thermal Spray Thickness 200 μm 200 μm Porosity 21% 0.1% Loss ratio 5.6 1 (standard) Adhesion Ratio Between Particles 1 (standard) 5.6

kind chief ingredient(%) Linear Expansion Coefficient 10 ^-6 / K Melting Point (K) Alumina Gray alumina Al ₂ O ₃ : Bal
TiO ₂ : 2.5
SiO ₂ : 1.0 7.4 2128 White alumina Al ₂ O ₃ +98 8.0 2272 Alumina
Titania 15% Titania Al ₂ O ₃ : Bal
TiO ₂ : 15 5.3 2113 40% Titania Al ₂ O ₃ : Bal
TiO ₂ : 40 7.5 2113 Alumina Zirconia Al ₂ O ₃ : Bal
ZrO ₂ : 24 6.3 2143 Zirconia 8% yttria ZrO ₂ : Bal
Y ₂ O ₃ : 8 9.7 2973 25% yttria ZrO ₂ : Bal
MgO: 24 8.7 2873 zircon ZrO ₂ : Bal
SiO ₂ : 33 7.6 2048 Alumina Chromia Al ₂ O ₃ : Bal
Cr ₂ O ₃ : Bal 8.0 2403 Chromia Cr ₂ O ₃ : 9.6 2573 Mullite 3Al ₂ O ₃ 2SiO ₂ 5.6 2163

Claims (6)

A thermally spray resistant body having a thermal sprayed coating having a thermal sprayed coating by an oxide-based ceramic thermal sprayed particle having an average particle diameter of 10 µm or less as a median diameter, wherein the thermal sprayed particles in the thermal sprayed coating are solidified after being thermally melted once. And, the sprayed object to be formed by the inner layer portion that is not heat-melted during spraying. The spray target according to claim 1, wherein the oxide ceramic spray coating has a thickness of 50 µm or less. 3. A to-be-sprayed body according to claim 1 or 2, wherein the sprayed spray has an underspray coating made of cement-based or metal-sprayed coating as a underspray of the oxide-based ceramic sprayed coating, and has a film thickness of 200 µm or less. . The subject according to any one of claims 1 to 3, wherein the oxide ceramics are gray alumina. The said sprayed object is a molten metal member which covered the molten metal containing Zn and / or Al, or the contact site which contacts the high temperature glass of 473K or more with the said thermal sprayed coating. Subject to be characterized in that the subject. The target object according to claim 1, wherein the thermal spraying particles are gray alumina or white alumina, the crystal structure of the surface layer portion is a γ phase changed from the α phase by thermal spraying, and the crystal structure of the inner layer portion is an α phase.

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