JP2001355081A - Heat resistant member and its production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material as a heat resistant member in which high temperature corrosive deterioration, thermal deterioration or the like are hard to occur, producible by a simple method at a low cost and further applicable even to complicated shape parts. SOLUTION: In this heat resistant member, the surface of a metallic substrate is provided with a nickel-aluminum alloy film obtained by diffusing aluminum metal into a nickel plating film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant member used for engines, turbines, various industrial furnaces and the like, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, high-temperature operation and long operation time of engines, turbines, and the like used in cogeneration and the like have been performed in order to improve energy conversion efficiency. Under such severe operating conditions, in particular, metal parts in a high temperature gas flowing part such as a combustion part, an exhaust part, a heat exchange part, such as an engine and a turbine, are mainly subjected to corrosion deterioration due to oxygen, heat deterioration, etc. Occurs, which is a serious problem in practical use.

For this reason, a nickel-based heat-resistant alloy may be used as a metal member in some cases. However, it has become difficult to provide both high-temperature strength and oxidation resistance with a heat-resistant alloy alone.

Therefore, it has been proposed to apply various coatings to the surface of the metal member in order to suppress the oxidative deterioration and the thermal deterioration of the metal member at a high temperature.

[0005] Among these coatings, those obtained by directly subjecting a metal member to aluminum diffusion treatment have been partially put to practical use.

However, the metal material subjected to the aluminum diffusion treatment is excellent in oxidation resistance at high temperatures, but since the aluminum in the surface layer diffuses into the metal member during use at high temperatures, the There is a problem that embrittlement of the material occurs.

[0007]

SUMMARY OF THE INVENTION The main object of the present invention is to:
It is hard to cause corrosion deterioration, heat deterioration, etc., engine, turbine,
An object of the present invention is to provide a heat-resistant member suitable for use in various industrial furnaces and the like.

Another object of the present invention is to provide a method of manufacturing a heat-resistant member which can be manufactured at a low cost by a simple method and can be easily applied to a complicated shape portion.

[0009]

The inventor of the present invention has conducted intensive studies in view of the above-mentioned problems of the prior art, and as a result, after forming a nickel-based plating film on a metal substrate, the nickel-based plating film was formed. It has been found that a nickel-aluminum alloy film whose aluminum content gradually decreases from the surface in the depth direction can be formed by diffusing aluminum into the film. Since the alloy film has good oxidation resistance and can prevent aluminum from diffusing into a metal member during use at a high temperature, the member on which this film is formed is extremely resistant as a heat-resistant member. Have been found to exhibit excellent characteristics, and the present invention has been completed here.

That is, the present invention provides the following heat-resistant member and a method for manufacturing the same. 1. A heat-resistant member having a nickel-aluminum-based alloy film formed by diffusing aluminum in a nickel-based plating film on a metal substrate. 2. Item 2. The heat-resistant member according to item 1, wherein the nickel-aluminum-based alloy film has a reduced aluminum content from the surface in a depth direction. 3. Item 3. The heat-resistant member according to Item 1 or 2, which is a member for a combustion portion, an exhaust portion, or a heat exchange portion of an engine or a turbine. 4. Engine or turbine piston top, piston ring, cylinder liner, exhaust valve back, turbine combustor, rotor blades, vanes, shroud turbine casing, turbocharger exhaust turbine, wastegate valve, exhaust manifold, exhaust flue, Item 4. The heat-resistant member according to item 3, which is a member for an oil cooler or an after cooler. 5. An engine or turbine provided with any one of the above items 1 to 4. 6. After forming a nickel-based plating film on a metal substrate,
A method for producing a heat-resistant member having a nickel-aluminum-based alloy film, wherein a heat treatment is performed in an aluminum penetrant containing aluminum powder to diffuse aluminum into the nickel-based plating film. 7. After forming a nickel-based plating film on a metal substrate,
A method for producing a heat-resistant member having a nickel-aluminum-based alloy film, comprising forming an aluminum film and then performing a heat treatment to diffuse aluminum metal into the nickel-based plating film. 8. Item 8. The method according to Item 7, wherein the method for forming the aluminum film is a hot-dip plating method, a metal spraying method, a vacuum evaporation method, a cathode sputtering method, or an ion plating method.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The heat-resistant member of the present invention is obtained by forming a nickel-aluminum-based alloy film formed by diffusing aluminum in a nickel-based plating film on a metal substrate.

The kind of metal serving as a base of the heat-resistant member of the present invention is not particularly limited as long as it is a metal forming a heat-resistant member used for an engine, a turbine, or the like. , Heat-resistant steel, stainless steel, etc.),
Copper, copper alloys, nickel, nickel alloys, cobalt, cobalt alloys and the like can be mentioned.

In order to form a nickel-aluminum alloy film on such a metal substrate, first, a nickel-based plating film is formed on the metal substrate, and then aluminum is diffused into the formed plating film. .

In order to form a nickel-based plating film, a plating treatment may be carried out using an electrolytic plating solution or an electroless plating solution according to a conventional method.

The nickel-based plating film is not only a plating film of nickel metal alone, but also one or more alloying elements such as cobalt, chromium, copper, manganese, tin, tungsten, boron and phosphorus in addition to nickel. It may be a nickel alloy plating film contained. In such a nickel alloy plating film, the nickel content is preferably about 50% by weight or more based on nickel and the alloy metal. Further, the nickel-based plating film may contain inorganic fine particles such as silicon oxide, aluminum oxide, titanium oxide, chromium oxide, zirconia oxide, yttrium oxide, hafnium oxide, silicon carbide, and silicon nitride. It is preferable that the content of these inorganic fine particles be about 20% by weight or less in the plating film. Further, when an electroless plating solution is used, phosphorus or boron as a component in the reducing agent is taken into the plating film.
The content of phosphorus or boron derived from these reducing agents is about 15% by weight or less for phosphorus and 10% or less for boron.
It is preferable that the content be not more than about% by weight.

The types of the electrolytic plating solution and the electroless plating solution are not particularly limited. Electrolytic plating solutions or electroless plating solutions of various known compositions containing a nickel salt as an essential component can be used.

As a plating method, electrolytic plating or electroless plating may be performed after pretreatment such as degreasing and pickling according to a conventional method. Further, in order to improve the adhesion of the nickel-based plating film to the substrate, if necessary, the nickel-based plating film may be formed after performing strike plating by a known method. When performing electroless plating directly on a substrate having no catalytic activity for electroless plating, the electroless plating may be performed after applying a catalyst according to a conventional method.

Regarding the thickness of the nickel-based plating film,
It varies depending on the material and shape of the member, the environment in which the member is used, the type of matrix metal, and the like.
It may be about 00 μm.

Next, after a nickel-based plating film is formed, aluminum is diffused into the plating film to form a nickel-aluminum-based alloy film.

The following method can be exemplified as a method for diffusing aluminum into the nickel-based plating film.

In the first method, after a nickel-based plating film is formed, the member on which the nickel-based plating film has been formed is placed in a powdery penetrant containing aluminum metal powder and subjected to a heat treatment to form a nickel-based plating film. This is a method in which aluminum is diffused and penetrated into the film. Heating temperature is 900-10
The heating temperature is preferably about 00 ° C., and the heating atmosphere may be a non-oxidizing atmosphere such as nitrogen or argon. The heating time may be set as appropriate according to the required diffusion amount of aluminum.

As an example of the composition of the powdery penetrant, a powdery composition composed of about 5 to 20% by weight of aluminum metal powder, about 0.1 to 5% by weight of ammonium chloride and the balance of alumina can be exemplified. By adding about 10 to 30% by weight of chromium metal powder to the penetrating agent, excessive reaction of aluminum can be suppressed and the degree of diffusion and penetration can be adjusted. In this case, a small amount of chromium diffuses into the plating film, but there is no adverse effect.

The particle size of the powdery penetrant is not particularly limited, but is usually not more than about 50 mesh (size of sieve 300 μm), preferably not more than about 100 mesh (size of sieve 150 μm), and further, Preferably, the mesh size is about 200 mesh (size of sieve: 75 μm) or less.

As a second method for diffusing aluminum into a nickel-based plating film, a nickel-based plating film is formed, an aluminum film is formed on the plating film, and then a heat treatment is carried out to form the nickel-based plating film. A method of diffusing aluminum into the system plating film can be exemplified.

The method of forming the aluminum film on the nickel-based plating film is not particularly limited, and examples thereof include a hot-dip plating method, a metal spraying method, a vacuum evaporation method, a cathode sputtering method, and an ion plating method. be able to. The specific conditions of these methods are not particularly limited, and may be in accordance with ordinary methods.

The thickness of the aluminum film is not particularly limited, and may be appropriately determined according to the amount of aluminum to be diffused and infiltrated. Usually, the thickness of the aluminum film is set so that aluminum does not excessively diffuse and adversely affect the metal substrate. It is preferable that the thickness be equal to or less than half the thickness of the nickel-based plating film.

For the heat treatment method, for example, a temperature of 8
It may be heated at about 00 to 1000 ° C. for about 1 to 5 hours. The atmosphere for the heat treatment may be a non-oxidizing atmosphere such as nitrogen or argon.

By the method described above, a nickel-aluminum alloy film can be formed by diffusing aluminum into the nickel-based plating film.
The formed nickel-aluminum alloy film has a structure in which the surface portion has the highest aluminum content and the aluminum content gradually decreases in the depth direction.

In the present invention, in order to prevent aluminum from diffusing into the metal substrate of the heat-resistant member, nickel-
It is preferable that the portion of the aluminum-based alloy film that is in contact with the metal substrate is made of only the nickel-based plating film without aluminum diffusion. Usually, a film in which a nickel-aluminum-based alloy film is formed by diffusion of aluminum in a nickel-based plating film (aluminum diffusion layer) and a portion (a nickel layer) consisting only of a nickel-based alloy in which aluminum is not diffused. The thickness ratio may be about 1: 99-99: 1, preferably about 30: 70-90: 10, and more preferably about 50: 50-90: 10. More preferred. The film thickness ratio between the aluminum diffusion layer and the nickel layer can be appropriately set by adjusting the thickness of the formed aluminum film, the heat treatment temperature, the heat treatment time, and the like.

The aluminum content in the nickel-aluminum alloy coating is not particularly limited, and is preferably about 20 to 70% by weight at the surface of the alloy coating, but more or less than this. May be contained in the surface portion of the alloy film.

According to the present invention, a heat-resistant member can be obtained by a simple method and at low cost by diffusing aluminum into a nickel-based plating film. The heat-resistant member on which such a nickel-aluminum alloy film is formed hardly undergoes high-temperature corrosion deterioration, heat deterioration, and the like. This is because Ni ₃ Al (Ni: 86.7% by weight-Al: 1) is contained in the nickel-aluminum alloy film.
(3.3% by weight). The Ni ₃ Al phase is called the γ prime phase, and
It is known to have very good mechanical strength at high temperatures of not less than ° C.

Further, since the aluminum content in the nickel-aluminum alloy film decreases from the surface in the depth direction, no aluminum is diffused or a small amount of aluminum is in contact with the metal substrate. It becomes a nickel-based plating film in which only aluminum is diffused. For this reason, there is a problem in the conventional method of directly performing aluminum diffusion treatment on a metal material. During use at a high temperature, aluminum in a surface layer diffuses into a metal member serving as a base and embrittlement of the metal material occurs. Can prevent it from happening.

The heat-resistant member of the present invention is applied to a combustion section, an exhaust section, a heat exchange section, etc. of an engine or a turbine.

The combustion section includes a piston top surface, a piston ring, a cylinder liner, a backside of an exhaust valve, a turbine combustor, a moving blade, a stationary blade, a shroud or a turbine casing. The exhaust unit includes a turbocharger exhaust turbine, a wastegate valve, an exhaust manifold, an exhaust flue, and the like. The heat exchange unit includes an oil cooler, an after cooler, and the like.

The member of the present invention can be effectively used as a material of a heat-resistant member used for these engines or turbines.

Further, the heat-resistant member of the present invention includes burners, radiant tubes, recuperators, hearth rolls, conveyor belts, skid hardware, various types of industrial furnaces such as a heating furnace, an annealing furnace, a heat treatment furnace, a baking furnace, and an incinerator. Heat shield plates, other metal parts, liquefaction and gasification of coal, oil shale and tar sands refining equipment, power boilers, petroleum refining, petrochemical industry, other chemical industry reaction vessels, reaction tubes, heat exchangers, transportation Can also be used as pipes and other various high-temperature members,
This is an extremely valuable member.

[0037]

The heat-resistant member of the present invention is hardly subject to high-temperature corrosion deterioration and heat deterioration, and can be manufactured by a simple method at low cost.

According to the surface treatment method employed in the present invention, even a member having a complicated shape can be easily manufactured.

[0039]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1 Electroplating was performed as follows. 1) Preparation of nickel strike plating solution A plating solution having the following composition was prepared.

Nickel chloride 245 g / l Hydrochloric acid 120 g / l 2) Preparation of electrolytic nickel plating solution A plating solution having the following composition was prepared.

Nickel sulfate 280 g / l Nickel chloride 45 g / l Boric acid 30 g / l 3) The following plating method was used as a material to be plated. Turbine blade Material: Ni heat resistant alloy MAR-M247 (Co: 10% by weight, Cr: 9% by weight, Mo: 0.8% by weight, W: 10% by weight, Al: 5.5% by weight, Ti: 1) 0.2% by weight, C:
0.1% by weight) Dimensions: Height 52mm, Width 15mm, Depth 40mm-Turbine stationary blade Material: Co heat-resistant alloy MAR-M509 (Ni: 10% by weight, Cr: 24% by weight, W: 7% by weight, Ti : 0.2% by weight) Dimensions: height 25mm, width 15mm, depth 45mm-Test piece (material: SUS304, 50mm x 50mm, thickness 3mm) The above-mentioned turbine rotor blade, turbine stationary blade and test piece are alkali degreasing liquid. Then, plating was performed by the following method using a negative electrode.

First, a nickel strike treatment was carried out for 2 minutes at a solution temperature of 25 ° C. and a current density of 10 A / dm ² using a nickel strike bath containing a nickel strike plating solution having the composition of 1) above.

Next, using a plating tank containing an electrolytic nickel plating solution having the composition of the above 2), a solution temperature of 50 ° C. and a pH of 4.
Electroplating was performed until the film thickness became 100 μm with screw stirring under the conditions of 0 and a current density of 4 A / dm ² to form an electrolytic nickel plating film. After the plating was completed, it was washed with water and dried at 100 ° C. for 5 minutes. 4. The material to be plated having the aluminum diffusion treatment and the electrolytic nickel plating film formed thereon was buried in a SUS container filled with a powdery penetrant having the following composition, and heated at 900 ° C. for 10 hours in an argon atmosphere. Aluminum 12.0% by weight Chromium 20.0% by weight Ammonium chloride 3.0% by weight Alumina 65.0% by weight Using a test piece, EPMA (JXA manufactured by JEOL Ltd.) was used.
-8900 RL), the quantitative analysis of the surface of the nickel-aluminum alloy film was as follows. <Surface analysis composition> Al: 34% by weight, Cr: 2% by weight, Ni: 61% by weight, O: 2% by weight. 70μ aluminum diffusion layer
m. The aluminum content was 34% by weight at the surface, 26% by weight at a depth of 10 μm from the surface, 21% by weight at a depth of 30 μm from the surface, 12% by weight at a depth of 50 μm from the surface, At a depth of 70 μm, the aluminum content decreased to 0% by weight in the depth direction.

The rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were installed at the first stage (atmospheric temperature 1150 ° C.) of a 2000 kW gas turbine.
The operation was performed for 00 hours.

After the operation for 1000 hours, the rotor blade and the stationary blade on which the nickel-aluminum-based alloy film was formed were cut, and the cross sections were analyzed with a metallographic microscope. Protected material, no oxide scale layer, Ni alloy substrate and Co
There was no oxidative deterioration of the alloy substrate.

Example 2 Electroplating was performed as follows. 1) Preparation of nickel strike plating solution A plating solution having the following composition was prepared.

Nickel chloride 245 g / l Hydrochloric acid 120 g / l 2) Preparation of electrolytic nickel-cobalt alloy plating solution A plating solution having the following composition was prepared.

Nickel sulfate 240 g / l Nickel chloride 45 g / l Boric acid 30 g / l Cobalt sulfate 15 g / l 3) Plating method The same moving blades, stationary blades and test pieces as in Example 1 were used. After degreasing with a degreasing solution, a nickel strike treatment was performed using the negative electrode.

Next, using a plating tank containing an electrolytic nickel-cobalt alloy plating solution having the composition of 2) above,
Electrolytic plating was performed under the conditions of a liquid temperature of 60 ° C., a pH of 4.0, and a current density of 4 A / dm ² with stirring with a screw until the film thickness became 100 μm to form an electrolytic nickel-cobalt alloy plating film. After plating, wash with water
Dry for 5 minutes at ° C. 4. The material to be plated having the aluminum diffusion treatment and the electrolytic nickel-cobalt alloy plating film formed thereon was buried in a SUS container filled with a powdery penetrant having the following composition, and treated at 900 ° C. for 10 hours in an argon atmosphere. <Penetrant composition> Aluminum 12.0% by weight Chromium 20.0% by weight Ammonium chloride 3.0% by weight Alumina 65.0% by weight Using a test piece, the surface of the nickel-aluminum alloy film was treated in the same manner as in Example 1. The results of the quantitative analysis were as follows. <Surface analysis composition> Al: 35% by weight, Cr: 2% by weight, Ni: 51% by weight, Co: 9% by weight, O: 2% by weight Also, the aluminum analysis in the cross-section depth direction of the test piece was performed in Example 1. As a result, the aluminum diffusion layer was 70 μm. Aluminum content is 3 on the surface
5% by weight, but 27% at a depth of 10 μm from the surface.
20% by weight at a depth of 30 μm from the surface, 11% by weight at a depth of 50 μm from the surface, 70 μm from the surface
At a depth of 0% by weight, the aluminum content decreased in the depth direction.

The rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were installed on the first stage (atmospheric temperature 1150 ° C.) of a 2000 kW gas turbine.
The operation was performed for 00 hours.

After 1000 hours of operation, the rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were cut, and the sections were analyzed with a metallurgical microscope. The material was protected, there was no oxide scale layer, and there was no oxidative degradation of the Ni alloy substrate and the Co alloy substrate.

Example 3 Electroplating was performed as follows. 1) Preparation of nickel strike plating solution A plating solution having the following composition was prepared.

Nickel chloride 245 g / l Hydrochloric acid 120 g / l 2) Preparation of electrolytic nickel-tungsten alloy plating solution A plating solution having the following composition was prepared.

Nickel sulfate 60 g / l Sodium tungstate 60 g / l Citric acid 90 g / l 3) Plating method Blades, stationary blades and test pieces similar to those in Example 1 were degreased with an alkaline degreasing solution in the same manner as in Example 1. After that, a nickel strike treatment was performed using the negative electrode.

Then, using a plating bath containing an electrolytic nickel-tungsten alloy plating solution having the composition of the above 2), screw stirring was performed under the conditions of a solution temperature of 65 ° C., a pH of 6.0, and a current density of 7 A / dm ^2. Meanwhile, electrolytic plating was performed until the film thickness became 100 μm to form an electrolytic nickel-tungsten alloy plating film. After the plating was completed, it was washed with water and dried at 100 ° C. for 5 minutes. 4. The material to be plated, on which an aluminum-diffusion treatment and an electrolytic nickel-tungsten alloy plating film are formed, is buried in a SUS container filled with a powdery penetrant having the following composition, and is baked under an argon atmosphere.
The treatment was performed at 0 ° C. for 10 hours. <Penetrant composition> Aluminum 12.0% by weight Chromium 20.0% by weight Ammonium chloride 3.0% by weight Alumina 65.0% by weight Using a test piece, the surface of the nickel-aluminum alloy film was treated in the same manner as in Example 1. The results of the quantitative analysis were as follows. <Surface analysis composition> Al: 35% by weight, Cr: 2% by weight, Ni: 42% by weight, W: 18% by weight, O: 2% by weight In addition, aluminum analysis in the section depth direction of the test piece was performed in Example 1. As a result, the aluminum diffusion layer was 70 μm. Aluminum content is 3 on the surface
5% by weight, but 25% at a depth of 10 μm from the surface.
% By weight, 19% by weight at a depth of 30 μm from the surface, 12% by weight at a depth of 50 μm from the surface, 70 μm from the surface
At a depth of 0% by weight, the aluminum content decreased in the depth direction.

The rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were installed on the first stage (atmospheric temperature 1150 ° C.) of a 2000 kW gas turbine.
The operation was performed for 00 hours.

After 1000 hours of operation, the rotor blade and the stationary blade on which the nickel-aluminum-based alloy film was formed were cut, and the sections were analyzed with a metallographic microscope. The material was protected, there was no oxide scale layer, and there was no oxidative degradation of the Ni alloy substrate and the Co alloy substrate.

Example 4 Electroplating was performed as follows. 1) Preparation of nickel strike plating solution A plating solution having the following composition was prepared.

Nickel chloride 245 g / l Hydrochloric acid 120 g / l 2) Preparation of electrolytic nickel-ZrO ₂ composite plating solution A plating solution having the following composition was prepared.

Nickel sulfate 280 g / l Nickel chloride 45 g / l Boric acid 30 g / l ZrO ₂ (containing 8% by weight of Y ₂ O ₃ ) 100 g / l 3) Plating method The same moving blade, stationary blade and blade as in Example 1 The test piece was degreased with an alkaline degreaser in the same manner as in Example 1, and then used as a negative electrode and subjected to a nickel strike treatment.

Next, using a plating tank containing an electrolytic nickel-ZrO ₂ composite plating solution having the composition of 2) above,
Electrolytic plating was performed under a condition of a liquid temperature of 50 ° C., a pH of 4.0, and a current density of 1 A / dm ² with a screw agitation until the film thickness became 100 μm to form an electrolytic nickel-ZrO ₂ composite plating film. After plating, wash with water
Dry for 5 minutes at ° C. 4. The material to be plated on which the aluminum-diffusion treatment and the electrolytic nickel-ZrO ₂ composite plating film were formed was buried in a SUS container filled with a powdery penetrant having the following composition, and 900 ° C. in an argon atmosphere.
For 10 hours. <Penetrant composition> Aluminum 12.0% by weight Chromium 20.0% by weight Ammonium chloride 3.0% by weight Alumina 65.0% by weight Using a test piece, the surface of the nickel-aluminum alloy film was treated in the same manner as in Example 1. The results of the quantitative analysis were as follows. <Surface analysis composition> Al: 32% by weight, Cr: 2% by weight, Ni: 48% by weight, Zr: 12% by weight, Y: 1% by weight, O: 4% by weight When the aluminum analysis was performed in the same manner as in Example 1, the aluminum diffusion layer was 70 μm. Aluminum content is 3 on the surface
2% by weight, but 26% at a depth of 10 μm from the surface.
20% by weight at a depth of 30 μm from the surface, 10% by weight at a depth of 50 μm from the surface, 70 μm from the surface
At a depth of 0% by weight, the aluminum content decreased in the depth direction.

The rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were installed on the first stage (atmospheric temperature 1150 ° C.) of a 2000 kW gas turbine.
The operation was performed for 00 hours.

After 1000 hours of operation, the rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were cut, and the sections were analyzed with a metallographic microscope. The material was protected, there was no oxide scale layer, and there was no oxidative degradation of the Ni alloy substrate and the Co alloy substrate.

Example 5 Electroless plating was performed as follows. 1) Preparation of nickel strike plating solution A plating solution having the following composition was prepared.

Nickel chloride 245 g / l Hydrochloric acid 120 g / l 2) Preparation of electroless nickel-boron alloy plating solution A plating solution having the following composition was prepared.

Nickel sulfate 27 g / l Sodium succinate 55 g / l Ammonium chloride 30 g / l Sodium citrate 30 g / l Boric acid 30 g / l Dimethylamine borane 3 g / l 3) Plating method Same as in Example 1, blade and static The blade and the test piece were degreased with an alkaline degreasing solution in the same manner as in Example 1, and then used as a negative electrode and subjected to a nickel strike treatment.

Next, using a plating tank containing an electroless nickel-boron alloy plating solution having the composition of 2),
Under a condition of a liquid temperature of 65 ° C. and a pH of 6.5, electroless plating was performed until the film thickness became 100 μm while stirring with a screw to form an electroless nickel-boron alloy plating film. After the plating was completed, it was washed with water and dried at 100 ° C. for 5 minutes. 4. The material to be plated, on which an aluminum diffusion treatment and an electroless nickel-boron alloy plating film are formed, is buried in a SUS container filled with a powdery penetrant having the following composition, and 900 ° C. in an argon atmosphere.
For 10 hours. <Penetrant composition> Aluminum 12.0% by weight Chromium 20.0% by weight Ammonium chloride 3.0% by weight Alumina 65.0% by weight Using a test piece, the surface of the nickel-aluminum alloy film was treated in the same manner as in Example 1. The results of the quantitative analysis were as follows. <Surface analysis composition> Al: 34% by weight, Cr: 2% by weight, Ni: 60% by weight, B: 1% by weight, O: 2% by weight In addition, aluminum analysis in the section depth direction of the test piece was performed in Example 1. As a result, the aluminum diffusion layer was 70 μm. Aluminum content is 3 on the surface
4% by weight, but 25% at a depth of 10 μm from the surface.
20% by weight at a depth of 30 μm from the surface, 10% by weight at a depth of 50 μm from the surface, 70 μm from the surface
At a depth of 0% by weight, the aluminum content decreased in the depth direction.

The rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were installed at the first stage (atmospheric temperature 1150 ° C.) of a 2000 kW gas turbine.
The operation was performed for 00 hours.

After 1000 hours of operation, the rotor blade and the stationary blade on which the nickel-aluminum-based alloy film was formed were cut, and the sections were analyzed with a metallographic microscope. The material was protected, there was no oxide scale layer, and there was no oxidative degradation of the Ni alloy substrate and the Co alloy substrate.

Example 6 In the same manner as in Example 1, the material to be plated on which the electrolytic nickel plating film 100 μm was formed was washed with water and dried at 100 ° C. for 5 minutes. Next, it was immersed in a molten aluminum plating bath at 700 ° C. for 1 minute to perform molten aluminum plating. After naturally cooling to room temperature, heat treatment was further performed at 800 ° C. for 3 hours to diffuse the aluminum plating layer on the surface into the nickel plating layer.

Using the test piece, a quantitative analysis of the surface of the nickel-aluminum alloy film was performed in the same manner as in Example 1, and the results were as follows. <Surface analysis composition> Al: 60% by weight, Ni: 38% by weight, O: 2% by weight Aluminum analysis in the cross-section depth direction of the test piece was performed in the same manner as in Example 1. It was 90 μm. Aluminum content is 6 at the surface
0% by weight, but 46% at a depth of 10 μm from the surface.
% By weight, 34% by weight at a depth of 30 μm from the surface, 21% by weight at a depth of 50 μm from the surface, 70 μm from the surface
At a depth of 10% by weight, and 0% at a depth of 90 μm from the surface.
The aluminum content decreased in the depth direction with respect to the weight%.

The rotor blade and the stationary blade on which the nickel-aluminum alloy film was formed were installed on the first stage (atmospheric temperature 1150 ° C.) of a 2000 kW gas turbine.
The operation was performed for 00 hours.

After 1000 hours of operation, the blades and vanes on which the nickel-aluminum-based alloy film was formed were cut, and the cross sections were analyzed with a metallographic microscope. The material was protected, there was no oxide scale layer, and there was no oxidative degradation of the Ni alloy substrate and the Co alloy substrate.

Comparative Example 1 A turbine and a stationary blade similar to those in Example 1 were installed on the first stage (atmospheric temperature 1150 ° C.) of a 2000 kW turbine without forming a plating film, and operated for 1000 hours. Was. The blade and the stationary blade after the operation for 1000 hours were cut, and the cross section was analyzed with a metallographic microscope.
An oxide scale layer was observed, and the nickel alloy of the moving blade and the cobalt alloy of the stationary blade were oxidized and degraded.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F01L 3/02 F01L 3/02 J 4K044 F02B 39/00 F02B 39/00 U F02C 7/00 F02C 7/00 C F02F 1/00 F02F 1/00 G 3/12 3/12 5/00 5/00 F F23R 3/42 F23R 3/42 CF term (reference) 3G002 EA05 EA06 3G005 FA13 GB22 GB81 GB86 JA16 KA05 KA07 3G024 AA25 AA26 AA27 FA09 FA14 GA18 HA07 4K024 AA03 AA14 AB01 BA01 BA02 BA07 BA09 BB04 BB26 BB28 BC10 GA16 4K028 CA02 CB02 CB04 CB05 CB06 CC01 CC03 4K044 AA02 AA06 AB10 BA06 BA10 BB04 BC11 CA18 CA18

Claims (8)

[Claims] 1. A heat-resistant member having a nickel-aluminum-based alloy film formed by diffusing aluminum in a nickel-based plating film on a metal substrate. 2. The heat-resistant member according to claim 1, wherein the nickel-aluminum-based alloy film has an aluminum content decreasing from a surface in a depth direction. 3. The heat-resistant member according to claim 1, which is a member for a combustion portion, an exhaust portion, or a heat exchange portion of an engine or a turbine. 4. A piston top surface of an engine or a turbine, a piston ring, a cylinder liner, an exhaust valve backside, a turbine combustor, a moving blade, a stationary blade, a shroud turbine casing, a turbocharger exhaust turbine, a wastegate valve, an exhaust manifold. The heat-resistant member according to claim 3, which is a member for an exhaust flue, an oil cooler, or an after cooler. 5. An engine or turbine comprising the member according to claim 1. 6. Nickel characterized in that after forming a nickel-based plating film on a metal substrate, heat treatment is performed in an aluminum penetrant containing aluminum powder to diffuse aluminum into the nickel-based plating film. -A method for producing a heat-resistant member having an aluminum-based alloy film. 7. A nickel plating method comprising: forming a nickel-based plating film on a metal substrate, forming an aluminum film, and then performing a heat treatment to diffuse aluminum metal into the nickel-based plating film. A method for producing a heat-resistant member having an aluminum-based alloy film. 8. The method according to claim 7, wherein the method for forming the aluminum film is a hot-dip plating method, a metal spraying method, a vacuum evaporation method, a cathode sputtering method or an ion plating method.