JP2013249824A - Method for manufacturing member for steam turbine plant, member for steam turbine plant, governing valve and steam turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a member for a steam turbine plant capable of presenting oxidation resistance even in high-temperature environment, and to provide a member for a steam turbine plant, a governing vale and a steam turbine.SOLUTION: A member for a steam turbine plant includes: a metal member made of a first metal material and having heat resistance; and a diffusing layer which is formed from a surface of the metal member to the inside of the metal member and where a second metal material different from the first metal material is diffused. The member for the steam turbine plant also includes a porous piled layer where the second metal material deposits on the surface of the metal member where the diffusing layer is formed. Moreover, the member for the steam turbine plant includes an oxide film formed on the surface of the piled layer and comprising an oxide of the second metal material.

Description

  Embodiments described herein relate generally to a method for manufacturing a member for a steam turbine facility having an oxide film on the surface, a member for a steam turbine facility, a steam control valve, and a steam turbine.

  In recent years, power generation equipment (steam turbine equipment) using a steam turbine is required to have high power generation efficiency, and the steam temperature tends to increase. When the steam temperature is 566 ° C. to 630 ° C., 9 to 12% Cr-based stainless steel or nickel-base heat-resistant alloy steel is generally used as a member used for steam turbine equipment.

  As an example of steam turbine equipment, for example, a steam control valve has a structure in which a valve rod, a bush, a sleeve, and a valve body slide in order to control the steam flow rate. Conventionally, a sliding member having such a sliding structure has been subjected to nitriding treatment in order to improve wear resistance.

  However, since oxidation resistance cannot be obtained by nitriding treatment, when the steam control valve is oxidized by high-temperature steam, the gap between the sliding members is reduced due to the generated oxide scale as the operation time elapses. As a result, there is a problem that the sliding member is fixed unless the oxide scale is removed for each periodic inspection.

  Further, as another example of the steam turbine equipment, for example, in the main steam pipe and the reheat steam pipe, there is a problem that the generated oxide scale grows and peels off.

JP-A-6-101769

  Thus, the conventional method for manufacturing a member for steam turbine equipment, a member for steam turbine equipment, a steam control valve, and a steam turbine have a problem that the oxidation resistance of the member is not sufficient. Embodiments of the present invention have been made to solve such a problem, and a method for manufacturing a member for a steam turbine facility capable of exhibiting oxidation resistance even in a high temperature environment, a member for a steam turbine facility, and a steam control valve It aims to provide a steam turbine.

  The steam turbine equipment member according to the embodiment includes a metal member made of a first metal material and having heat resistance, and a second member different from the first metal material formed from the surface of the metal member to the inside. A diffusion layer in which a metal material is diffused is provided. Furthermore, a porous deposition layer in which a second metal material is deposited on the surface of the metal member on which the diffusion layer is formed is provided. In addition, an oxide film made of an oxide of the second metal material is provided on the surface of the deposited layer.

It is sectional drawing which shows the structure of the member for steam turbine equipment of 1st Embodiment. It is a figure which shows the structure of the manufacturing apparatus for enforcing the manufacturing method of 1st Embodiment. It is a flowchart which shows the manufacturing method of 1st Embodiment. It is sectional drawing which shows the mode of the member for steam turbine equipment in the manufacturing method of 1st Embodiment. It is sectional drawing which shows the mode of the member for steam turbine equipment in the manufacturing method of 1st Embodiment. It is sectional drawing which shows the mode of the member for steam turbine equipment in the manufacturing method of 1st Embodiment. It is sectional drawing which shows the mode of the member for steam turbine equipment in the manufacturing method of 1st Embodiment. It is sectional drawing which shows the mode of the member for steam turbine equipment in the manufacturing method of 1st Embodiment. It is sectional drawing which shows the structural example of the steam control valve using the member manufactured by the manufacturing method of 4th Embodiment. It is a figure which shows the structural example of the steam turbine using the member manufactured with the manufacturing method of 5th Embodiment.

(Member for Steam Turbine Equipment of First Embodiment)
In the steam turbine equipment member of the first embodiment, the oxidation resistance that can be used for a long time under high-temperature oxidation conditions is that the oxide film formed on the surface of the member in the initial stage of oxidation has protection. It is exhibited by preventing the subsequent generation of new oxides. The protective property exhibited by the oxide film varies depending on the type of oxide forming the film, but the film needs to be dense. Such a dense oxide film not only does not allow oxygen in the atmosphere to permeate, but also prevents a metal component constituting the steam turbine equipment member from being eluted through the oxide film. Accordingly, generation of metal oxide (oxide scale) can be suppressed. In the manufacturing method of the first embodiment, a porous deposition layer is formed by pulse discharge. This deposited layer is not only porous, but also has a high hardness. Furthermore, by heating the deposited layer under predetermined conditions, the electrode material in the deposited layer generates a dense oxide not only on the surface of the deposited layer but also on the surface of the vacancies in the deposited layer. Therefore, it can have a dense and high hardness and excellent oxidation resistance, protective property, and sliding property.

  Thus, according to the steam turbine equipment member of the embodiment, generation of new oxide (on the oxide film) during operation of the steam turbine equipment is suppressed, and use at a higher temperature or for a longer period of time. Is possible. Further, the turbine equipment member of the embodiment has excellent slidability, and can maintain this slidability even when used at high temperatures.

  FIG. 1 shows an example of the configuration of a steam turbine equipment member according to the first embodiment. As shown in FIG. 1, in the steam turbine equipment member 1 of the first embodiment, a diffusion layer 12 is formed on a surface layer portion of one surface of a metal member 10 as a base material. In the steam turbine equipment member 1 according to this embodiment, the deposition layer 25 is formed on the surface of the metal member 10 corresponding to the diffusion layer 12. The deposited layer 25 is a porous layer having pores.

  The diffusion layer 12 is a modified layer in which the electrode material 22 diffuses and penetrates from the surface to be processed of the metal member 10 constituting the steam turbine equipment member 1 toward the inside. In the diffusion layer 12, the electrode material 22 dissolves with the components constituting the metal member, the electrode material 22 diffuses and penetrates into the metal member 10, and the content of the electrode material 22 is directed toward the surface of the metal member 10 in the thickness direction. It shows the properties of a compositionally graded layer that gradually increases.

  An oxide film 26 is formed on the surface of the deposited layer 25. The oxide film 26 is formed on the surface of the deposition layer 25, that is, the surface of the deposition layer 25 including the inner wall surface of the pores inside the deposition layer 25. The oxide film 26 is composed of part or all of the oxide of the electrode material 22 in the deposition layer 25. In the present embodiment, the metal member 10, the diffusion layer 12, the deposition layer 25, and the oxide film 26 do not necessarily have a clear boundary, and may have a continuous composition. It goes without saying that the oxide film 26 may be part or all of the deposited layer 25.

  As a manufacturing method of the member 1 for steam turbine equipment which concerns on 1st Embodiment, first, in the liquid or air which has electrical insulation, the to-be-processed surface of the metal member 10 (1st metal material), metal In a state where the electrode 20 made of a material different from that of the member 10 is held in the minute gap, a pulsed discharge is generated in the minute gap. The diffusion layer 12 and the deposited layer are formed by welding and depositing the electrode material 22 constituting the electrode 20 on the surface of the metal member 10 by the energy of this discharge. The diffusion layer 12 exhibits the property of a composition gradient layer because the welded portion is partially heated when the electrode material 22 is welded to the surface to be treated of the metal member 10 by pulsed discharge. This is because of diffusion into the metal member 10. Further, as will be described later, a porous deposition layer can be formed by appropriately determining the composition and physical properties of the electrode material 22, conditions for pulse discharge, and the like. Thereafter, the deposited layer 25 can be obtained by oxidizing the deposited layer formed on the metal member 10.

(Production apparatus of the first embodiment)
Next, with reference to FIG. 2, the manufacturing apparatus used for the manufacturing method of the member for steam turbine equipment of 1st Embodiment is demonstrated.

[Configuration of manufacturing equipment]
FIG. 2 shows an outline of the manufacturing apparatus 2 used in the manufacturing method of the first embodiment. As shown in FIG. 2, the manufacturing apparatus 2 according to the first embodiment includes a processing tank 30 that stores a processing liquid 40. The metal member 10 to which the connection line is connected is immersed in the processing liquid 40 of the processing tank 30. In the vicinity of the surface to be processed of the metal member 10, a rod-shaped electrode 20 is disposed so as to face the surface to be processed.

  The metal member 10 and the electrode 20 form a closed circuit. That is, the metal member 10 is connected to the positive electrode of the DC power source E, and the electrode 20 is connected to the negative electrode of the DC power source E via the current limiting resistor R and the switching element Tr. The processing liquid 40 is, for example, oil having electrical insulation. The working fluid 40 acts to prevent the metal member 10 and the electrode material 22 from being oxidized without being controlled. This is because the oxide film 26 becomes inhomogeneous due to natural oxidation without being controlled, and the protective property may be inferior. The switching element Tr applies or stops applying the voltage of the DC power source E between the electrode 20 and the metal member 10.

  Connected between the metal member 10 and the electrode 20 is a discharge detector 50 that detects a discharge generated between the metal member 10 and the electrode 20. For example, the discharge detection unit 50 monitors the potential difference between the metal member 10 and the electrode 20 and detects the occurrence of the discharge by detecting the fluctuation of the potential difference caused by the discharge. The detection result of the discharge detection unit 50 is given to the control unit 60. The control unit 60 controls the open / closed state of the switching element Tr based on the presence or absence of occurrence of discharge detected by the discharge detection unit 50.

  In the example shown in FIG. 2, the switching element Tr is realized by a bipolar transistor element. That is, the control signal of the control unit 60 is received at the base terminal, and the connection of the current limiting resistor R connected to the negative electrode and the emitter of the DC power supply E connected to the collector is controlled on and off.

  The current limiting resistor R sets a current value flowing through the closed circuit. This current value is a parameter that determines the mode of discharge generated between the metal member 10 and the electrode 20. In addition, the control unit 60 controls the opening / closing timing of the switching element Tr to control the voltage waveform applied to the metal member 10 and the electrode 20 to a predetermined shape. This voltage waveform is also a parameter that determines the mode of discharge generated in the metal member 10 and the electrode 20. That is, the discharge state of the metal member 10 and the electrode 20 can be controlled by adjusting the resistance value of the current limiting resistor R and the control signal of the control unit 60. Since the generation of the discharge is detected and the pulse discharge is generated, the homogeneous diffusion layer 12 and the deposition layer 25 can be formed in the manufacturing method of the present embodiment in which the energy for each pulse can be made constant.

  When a material having a relatively high resistance value such as Si (silicon) is used as the electrode material 22, a voltage drop caused by a current flowing through the electrode 20 at the time of occurrence of discharge is a voltage between the metal member 10 and the electrode 20 at the time of pulse discharge. Therefore, there is a possibility that the discharge detection unit 50 cannot recognize the occurrence of the discharge. In this case, the voltage application time and the stop time are determined in advance, and the voltage for each pulse can be controlled without detecting the pulse discharge by periodically applying and stopping the voltage.

  Since the manufacturing method of this embodiment uses pulse discharge as described above, the thickness of the diffusion layer 12 and the deposited layer 25 can be easily adjusted by changing the number of discharge pulses and the pulse discharge time. Since the diffusion layer 12 and the deposition layer 25 are formed only in the portion where the discharge occurs, it can be locally formed in a desired portion.

(Manufacturing method of the first embodiment)
Then, the manufacturing method of 1st Embodiment is demonstrated in detail with reference to FIGS. 2-3, 4A-4E. In the manufacturing apparatus 2 shown in FIG. 2, as shown in FIG. 4A, the electrode 20 is held near the surface to be processed of the metal member 10 (step 100; hereinafter referred to as “S100”). The holding of the electrode 20 may be realized by using an arm or an electrode feeding mechanism (not shown), or may be held directly by an operator.

  The distance between the metal member 10 and the electrode 20 is a distance at which a pulsed discharge is generated by applying a voltage, and the electrode material 22 can diffuse and penetrate from the surface of the metal member to the inside and be deposited. is there. In the first embodiment, the metal member 10 and the electrode 20 are held at intervals according to the magnitude of the voltage applied between them.

[Pulse discharge]
The controller 60 controls the switching element Tr to turn it on and applies a voltage to the metal member 10 and the electrode 20. When the distance between the metal member 10 and the electrode 20 approaches, a discharge occurs between the metal member 10 and the electrode 20 as shown in FIG. 4B (S102).

  At this time, the resistance value and the voltage waveform calculated based on the current value and pulse width (discharge duration) of the current pulse supplied to the metal member 10 and the electrode 20 and the discharge pause time (time during which no voltage is applied) are preliminarily represented as current. The limit resistor R and the control unit 60 are set in advance. When the discharge occurs, the discharge detection unit 50 detects the occurrence of discharge based on the voltage drop and reduction timing between the metal member 10 and the electrode 20, and the control unit 60 performs a predetermined time from the detection of the discharge occurrence. After (pulse width), the switching element Tr is controlled to be turned off. The control unit 60 turns the switching element Tr on again after a predetermined time (resting time) from when the switching element Tr is turned off. By repeating these operations, a discharge corresponding to the set current waveform can be continuously generated.

[Deposition layer formation]
When discharge is continuously generated between the metal member 10 and the electrode 20, the electrode material 22 constituting the electrode 20 jumps out toward the surface to be processed of the metal member 10 as shown in FIG. 4B. Further, as shown in FIG. 4C, the electrode material 22 released to the surface to be processed of the metal member 10 by the electric discharge diffuses inward from the surface to be processed of the metal member 10 to form the diffusion layer 12 and Deposits on the treated surface. As a result, a porous deposition layer 24 is formed on the surface to be processed of the metal member 10 (S104).

  The deposited layer 24 is generally composed of the electrode material 22, and the electrode material 22 is in an extremely dense state. In the surface layer portion (diffusion layer 12) of the surface to be processed of the metal member 10, the composition ratio of the electrode material 22 in the metal member 10 gradually increases from the surface to be processed toward the inside of the metal member 10 in the thickness direction of the surface to be processed. It exhibits the properties of a composition gradient layer that becomes smaller.

Here, the thickness of the diffusion layer 12 is preferably about 10 [μm]. This is because if the thickness of the diffusion layer 12 is too thick, the amount of heat input increases and the metal member may be deformed or altered, or its strength may be reduced. The diffusion layer 12 and the deposition layer 24 can be formed on all or part of the surface of the metal member 10 as necessary.
After the deposition layer 24 is formed, the upper surface of the deposition layer 24 is processed with a machine tool or the like to the minimum if necessary, so that the steam turbine equipment member 1 has a predetermined shape and size. The surface of 1 can have a desired surface roughness (S105).

[Heat oxidation treatment of deposited layer]
In the manufacturing method of this embodiment, after forming the deposited layer 24, a heating oxidation process is performed by the heating means 35 as shown in FIG. 4D. By this heat oxidation treatment, an oxide film 26 is formed on the surface of the deposited layer 25 and the surface of the vacancies in the deposited layer 25. By such treatment, it is possible to obtain a deposited layer 25 that is densified and has improved protection. Moreover, the surface layer part of the member 1 for steam turbine equipment can be made dense and harder, and the slidability can be improved.

  The temperature of the heat oxidation treatment is equal to or lower than the tempering temperature of the metal member 10. This is to prevent a decrease in protection due to a decrease in strength, alteration or deformation of the metal member 10 and the deposited layer 25, and a coarsening of crystal grains in the deposited layer 25 or the oxide film 26. Specifically, the temperature of the heat oxidation treatment is preferably about 600 to 650 ° C. which is equal to or lower than the tempering temperature of the metal member 10 and at which the electrode material 22 is oxidized. The heating means 35 is not limited as long as it can obtain the above-described temperature. Specifically, heating methods such as a burner, an electron beam, a laser, arc heating with an arc current, and plasma heating are exemplified. Further, a method of heating using heat generated when the particles collide (for example, a peening process described later) or other known methods capable of local heating can be used.

  Moreover, in the manufacturing method of this embodiment, the porous deposition layer 25 with very small pores is formed by pulse discharge. The deposited layer 25 is formed with a certain thickness and is formed of the electrode material 22, and therefore the deposited layer 25 itself has a high hardness. Further, since the deposited layer 25 is porous, it has excellent slidability. Furthermore, by oxidizing the electrode material 22 on the surface of the deposited layer 25, it can be made denser and excellent in oxidation resistance and slidability. Furthermore, since the oxide film 26 has a high hardness, it has excellent slidability and can improve wear resistance due to sliding. Here, when the electrode material 22 is a Co-based hard alloy (Cr content is 10 to 30 weights), Co itself has oxidation resistance, so that generation of oxide scale in the oxide film 26 can be further suppressed. If the generation of oxide scale is suppressed, not only can the gap between the members constituting the steam turbine be properly maintained for a long period of time, but also slidability can be improved.

  As described above, the manufacturing method of the present embodiment makes it possible to obtain the steam turbine equipment member 1 having excellent sliding characteristics and oxidation resistance.

In the manufacturing method of this embodiment, since pulse discharge is used, it is easy to make the deposited layer 25 porous compared to methods such as welding and thermal spraying. By making the deposited layer 24 porous as shown in FIG. 4C, the oxide film 26 is formed on the upper surface of the deposited layer 25 and the surface of the pores in the deposited layer 25 (shown in FIGS. 4D and 4E). Can be. Elements that make the deposited layer 25 porous include the following 1) to 6). In the manufacturing method of the present embodiment, the diffusion layer 12 and the porous deposited layer 25 are formed in consideration of these elements. Can do.
1) Constituent particle diameter of electrode material 2) Coupling force of constituent particles of electrode material 3) Thermal conductivity and heat transfer coefficient of electrode material, metal member and machining fluid 4) Current value during discharge process 5) During discharge process Pulse time setting (ON / OFF time)
6) Fine particle concentration in machining fluid

  The electrode 20 of the present embodiment is configured by a method of compression molding a powder of the electrode material 22 that is the second metal material. The powder of the electrode material 22 is ejected from the electrode 20 toward the metal member 10 by discharge energy and is deposited while melting. The surface area of the powder is proportional to the square of the particle size, whereas the volume is proportional to the cube of the particle size. At this time, the smaller the particle diameter of the powder, the larger the thermal energy per unit volume. Yes (element 1).

  Further, in the pulse discharge treatment of the present embodiment, pulse discharge is repeatedly generated, and small bulges (projections) including the electrode material 22 are gradually laminated and welded with discharge energy. By increasing the discharge time or increasing the discharge current, the energy for each pulse can be increased. If it does so, the protrusion formed by one discharge (pulse) and the space | gap between protrusions will become large. Further, the size of the projections and the gaps between the projections are determined according to the energy for each pulse, the constituent particle diameter of the electrode material 22, the binding force of the constituent particles of the electrode material 22 (elements 1 and 2). .

  In the manufacturing method of the present embodiment, the electrode material 22 is discharged toward the surface of the metal member 10 using pulse discharge. The electrode material 22 is melted and welded to the surface of the metal member 10 by the heat of discharge and diffuses and penetrates from the surface of the metal member 10 to the inside. When the thermal conductivity of the metal member 10 and the electrode material 22 is large, the heat of the molten electrode material 22 is conducted and diffused into the metal member 10 and the deposited layer 24. Then, the molten electrode material 22 is re-solidified to form a deposited layer 24. Further, the electrode material 22 is deposited by repeating the discharge. Therefore, when the thermal conductivity of the metal member 10 and the electrode material 22 is large, heat can be diffused even if the contact area between the particles constituting the metal member 10 and the electrode material 22 is small, and the molten electrode material 22 is solidified. Happens fast. Therefore, if the thermal conductivity of the metal member 10 or the electrode material 22 is large, it solidifies before the gaps between the projections stacked by discharge are filled, so that the deposition layer 24 can be made porous (element 3).

  Considering the thermal conductivity of the electrode material 22 as described above, the particle diameter of the particles constituting the electrode material 22, pulse discharge conditions, and other factors, the deposited layer 24 having minute pores can be formed. .

[Operation of Manufacturing Method of First Embodiment]
In the manufacturing method of this embodiment, the porous deposition layer 24 is formed by pulse discharge. Then, the electrode material 22 on the surface of the deposition layer 24 (including the surface of vacancies in the deposition layer 24) is oxidized to obtain the deposition layer 25 on which the oxide film 26 is formed. Since the deposited layer 24 is porous, it has many pores, and oxide is also generated at the interface of the pores. The deposited layer 25 is extremely dense, highly protective, and has high hardness. In addition, voids in the pores are reduced by the generated oxide, and the deposited layer 24 becomes a denser deposited layer 25. Furthermore, since the electrode material 22 of the above-described embodiment is used, the oxide film 26 is dense and hard and is not easily broken or eroded, and the protection can be enhanced. For example, when Cr ₂ O ₃ (chromium oxide) derived from Cr of the electrode material 22 is generated as the oxide film 26, the protective properties are excellent. This is because Cr ₂ O ₃ has a corundum type structure and is stable to heat, and is passive and has excellent oxidation resistance.

When the amount of the electrode material 22 is small, an oxide scale is generated. These are, for example, Cr contained in the electrode material 22 or the metal member 10, and FeCr ₂ O ₄ , Fe ₃ O ₄ , NiCr ₂ O ₄ , CoCr ₂ O _4, etc. generated by Fe, Ni, Co, or the like. In the manufacturing method of the present embodiment, the deposited layer 25 made of the electrode material 22 is formed using pulse discharge, and the oxide film 26 having excellent protection can be obtained.

  Since the deposited layer 25 of this embodiment is porous, its thermal conductivity is smaller than that of a general solid metal material. Therefore, during the heat oxidation treatment, heat from the surface is not easily transmitted to the metal member 10 as the base material, and heat input to the metal member 10 can be minimized.

  The oxide film 26 formed by heating is dense and has excellent slidability. Further, since the deposited layer 25 is porous, it can absorb and store thermal energy. Therefore, energy is accumulated at a high temperature, diffusion bonding between particles is promoted, and grain boundaries and voids are reduced. As a result, the bond strength between the particles increases, that is, the hardness and strength of the deposited layer 25 and the oxide film 26 can be improved, and the slidability can be improved.

Moreover, in the manufacturing method of 1st Embodiment, the surface modification of the to-be-processed surface of the metal member 10 is performed by pulsed discharge. That is, the heat input to the member can be reduced as compared with the conventional coating by welding, thermal spraying, sintering, or the like. Therefore, the target member is hardly deformed. Furthermore, in the manufacturing method of this embodiment, in the diffusion layer 12, the components of the electrode material 22 penetrate from the surface of the metal member 10 to the inside and are melted and joined. Therefore, the diffusion layer 12 is not peeled off from the metal member 10. Further, no welding is used, and no residual stress is generated in the diffusion layer 12. The diffusion layer 12 is a functionally graded material, and the thermal stress for reducing the difference in linear expansion coefficient is alleviated. Therefore, no crack occurs in the diffusion layer 12.
As an existing technique, there is a method of forming a built-up portion in which a Co-based hard alloy (for example, Stellite (registered trademark)) is built up by plasma welding. In the manufacturing method of this embodiment, the deposited layer 25 can be made to have a low hardness by pulse discharge as compared with the existing plasma welding overlay. Therefore, by combining the manufacturing method of this embodiment and the manufacturing method using plasma welding, a difference in both surface hardnesses can be produced, which is desirable from the viewpoint of galling prevention. Moreover, in the manufacturing method of this embodiment, the oxide film 26 is formed on the surface of the porous deposition layer 25, and the steam turbine equipment member having excellent slidability that is not present in the built-up portion by the existing plasma welding. 1 can be obtained. Thus, according to the manufacturing method of 1st Embodiment, the member 1 for steam turbine equipment which is precise | minute and hard and cannot be easily destroyed or eroded can be manufactured.

  In the manufacturing method and manufacturing apparatus of the above-described embodiment, a transistor is used as the switching element Tr. However, any element can be used as long as it can control the application of voltage. Moreover, in the said embodiment, although control of the current value is implement | achieved by the current limiting resistor R, it cannot be overemphasized that another method may be sufficient if a current value can be controlled.

[Base materials and electrodes]
Here, the metal member 10 and the electrode 20 in the present embodiment will be described. The metal member 10 (first metal material) of the steam turbine equipment member 1 in this embodiment is made of a material generally used as a high-temperature material for a steam turbine plant. For example, chromium-molybdenum steel containing any of Cr (chromium), Mo (molybdenum), V (vanadium), W (tungsten), Mn (manganese), Ti (titanium), Ni (nickel), and Co (cobalt). Further, chromium-molybdenum-vanadium steel, chromium-molybdenum-tungsten-vanadium steel, 9% chromium steel, 12% chromium steel, Ni-base or Co-base heat-resistant alloy steel, and the like can be used.

  The electrode material 22 may be made of a metal suitable for forming the oxide film 26, such as Co, Cr, Ni, W, Mo, Fe, Si, Ti, Zr, Cu, and Al.

  The electrode material 22 of the present embodiment uses a metal material having high thermal conductivity in order to make the deposited layer 25 porous. Specifically, the electrode material 22 preferably has a thermal conductivity of 90 [W / m · K] or more. Examples of the material having a thermal conductivity of 90 [W / m · K] or more include Co, Ni, Cu, Al, and alloys thereof. By using the material as the electrode material 22, a porous deposited layer can be obtained. Further, for the same reason as described above, it is desirable that the metal member 10 as the base material also has a high thermal conductivity.

  Among the above, Co is excellent in oxidation resistance. Therefore, in this embodiment, the production | generation of the oxide scale originating in the metal member 10 can be suppressed because the electrode material 22 contains Co which is excellent in protective property. When the electrode material 22 of this embodiment is a Co-based hard alloy (Cr content is 10 to 30% by weight), generation of oxide scale can be suppressed even at high temperatures. Moreover, Co has a higher hardness than steel materials, and the hardness does not decrease much at high temperatures. Therefore, when the electrode material 22 contains Co, the turbine equipment member 1 excellent in oxidation resistance and erosion resistance can be obtained, and is particularly suitable for a member having a sliding portion and a fitting portion.

When the electrode material 22 used in the manufacturing method of the present embodiment contains Cr, the turbine equipment member 1 having excellent oxidation resistance and slidability can be obtained. This is because Cr (chromium) generates Cr ₂ O ₃ having lubricity at high temperature by oxidation. This is also because Cr ₂ O ₃ is passive and stable to heat. Thus, if the electrode material 22 contains Cr, a dense and highly protective oxide film 26 can be generated. The Cr content with respect to the electrode material 22 is preferably 10% by weight or more. When the Cr content is 10% by weight or more, Cr ₂ O ₃ is easily generated, and the friction coefficient of the oxide film 26 can be reduced, so that the slidability can be improved.

When the electrode material 22 used in the manufacturing method of the present embodiment contains Ni (nickel), it is possible to impart ductility to the deposited layer 25 and to reduce the occurrence of cracks and defects during and after the pulse discharge process. In particular, crack resistance can be improved when a pulse discharge treatment is applied to a large area. In this case, the Ni content is preferably less than 20% by weight. If the Ni content is 20% by weight or more, the coefficient of friction on the surface of the oxide film 26 is large and the slidability may be poor. Moreover, there is a possibility of inhibiting the formation of Cr ₂ O ₃ at high temperatures.

When the electrode material 22 used in the manufacturing method of the present embodiment contains Si (silicon), silicon oxide is generated at a high temperature, and the sliding characteristics are improved by a synergistic effect with Cr ₂ O ₃ . SiO _{2 which} is silicon oxide is amorphous. In the manufacturing method according to the present embodiment, the electrode material particles melted by the discharge energy are stacked to form the deposition layer 25, and therefore there is a grain boundary between the particles, that is, a grain boundary in the deposition layer 25. Formation of SiO _{2 at the} crystal grain boundary prevents oxygen permeation into the deposition layer 25 under high temperature conditions, and as a result, suppresses the metal member 10 from being oxidized and generating oxide scale. it can. By using the second metal material containing Fe and Si and setting the Si content of the deposited layer 25 to 1 to 20% by weight, excellent oxidation resistance and erosion resistance can be obtained. In this case, the thickness of the deposited layer 25 is preferably 5 to 10 μm. Furthermore, the deposited layer 25 preferably contains amorphous silicon oxide, preferably has a Si content of 3 to 11% by weight and a hardness of 600 to 1100 HV.

  Further, when the electrode material 22 used in the manufacturing method of the present embodiment further contains C (carbon) or N (nitrogen), the electrode material 22 (second metal) is formed on the surface of the deposition layer 25 during the heat oxidation process described later. Material) carbides and nitrides can be produced. Since this carbide and nitride have heat resistance and excellent strength, a stronger member 1 for steam turbine equipment can be obtained. As the electrode material 22, a metal, a metal compound, or ceramic can be used.

  The electrode 20 of the present embodiment can be configured by a molded body compression-molded from a powder of the electrode material 22 (second metal material) or a molded body heat-treated. The shape of the electrode 20 can be determined in accordance with the shape and application of the steam turbine equipment member 1 to be manufactured and the mode of the apparatus used for the pulse discharge process. For example, when the cross-sectional shape of the electrode 20 is rectangular according to the width or axial length of the metal member 10, or when the metal member 10 is cylindrical, the surface of the electrode 20 is the outer periphery of the metal member 10. It can be arcuate along the surface. By appropriately changing the shape of the electrode 20, a pulsed discharge can be stably generated, and the diffusion layer 12 and the deposition layer 25 can be formed uniformly. Further, the diffusion layer 12 and the deposition layer 25 can be formed on a desired portion of the metal member 10.

(Modification of the manufacturing apparatus of the first embodiment)
In the said embodiment, although discharge is generated in the processing liquid 40 stored in the processing tank 30, it is not limited to this. For example, the same effect can be obtained by discharging in an inert gas such as argon instead of the working fluid. That is, as long as it is in an atmosphere that does not oxidize the metal member randomly, it may be processed in any environment.

  Specifically, for example, as in TIG welding, a torch to which the electrode 20 is attached and a gas cylinder that supplies gas to the torch via a gas pipe are prepared. The inert gas supplied from the gas cylinder is configured to be ejected from the periphery of the electrode 20 toward the surface to be processed of the metal member 10 through the gas pipe and the gas flow path formed in the torch. In order to prevent the diffusion of the inert gas, a cover may be provided around the torch. The torch to which the electrode 20 is attached includes a scanning arm for manually or supporting the torch and moving the torch to perform a scanning operation, a scanning arm driving mechanism for driving the scanning arm, and the like. The electrode material is made of, for example, Cr, and the electrode has a rod shape suitable for a torch or a wire shape for continuous supply.

  With the manufacturing apparatus having such a configuration, the degree of freedom of the pulse discharge work is increased (workability is improved) and, for example, the pulse discharge process can be performed on the metal member 10 having a three-dimensional curved surface. It becomes possible to manufacture the member 1 for steam turbine equipment and the member 1 for steam turbine equipment of the magnitude | size which cannot be immersed in a processing tank.

  That is, in the embodiment of the present invention, the oxidizing material that forms the oxide film 26 is formed as the deposition layer 25 on the steam turbine equipment member 1 by pulse discharge, so that the metal member 10 that is the material of the steam turbine equipment member 1 is used. Is not particularly limited.

  According to the first embodiment, almost no difference in linear expansion coefficient occurs in the diffusion layer 12. Therefore, it is not necessary to consider the difference in linear expansion coefficient. Therefore, the degree of freedom in selecting and combining the metal member 10 and the electrode material 22 that can form the diffusion layer 12 can be increased and determined according to the steam temperature and the high temperature strength.

(Second Embodiment)
Next, a manufacturing method according to the second embodiment will be described. The manufacturing method of this embodiment is a modification of the heating method in the heat oxidation treatment of the first embodiment. In the following description, elements that are the same as those in the first embodiment are denoted by the same reference numerals, and redundant descriptions are omitted.

  As shown in FIG. 4C, the metal member 10 on which the deposited layer 24 is formed is used to manufacture a part that is exposed to high-temperature steam in a steam turbine facility. Thereafter, by operating the equipment, the surface of the vacancies in the deposited layer 25 and the electrode material 22 on the upper surface of the deposited layer 25 are oxidized by high-temperature steam (S106). As a result, an oxide film 26 is formed on the surface of the deposited layer 25.

  In the manufacturing method of this embodiment, after forming the deposition layer 24, it applies to a steam turbine plant as it is. Since the plant in operation is extremely hot, the high temperature steam reacts with the electrode material 22 within several hours to several tens of hours from the start of operation, and the oxide film 26 can be formed in a very short time.

  The deposited layer 25 formed with the oxide film 26 thus obtained can provide the same operations and effects as the oxide film 26 of the first embodiment. That is, also in this embodiment, it is possible to provide the steam turbine equipment member 1 having excellent sliding characteristics and oxidation resistance.

(Third embodiment)
In the manufacturing method of the third embodiment, peening is performed after the oxide film 26 is formed in the manufacturing method of the first embodiment (after step 106 in FIG. 3). In the following description, elements that are the same as those in the first embodiment are denoted by the same reference numerals, and redundant descriptions are omitted.

  In the pulse discharge process, the heat input to the metal member 10 is extremely small, but the metal member 10 and the electrode material 22 are repeatedly melted and re-solidified in the process of repeating the pulse discharge. Therefore, a residual tensile stress accompanying shrinkage during resolidification occurs in the surface layer portion of the deposited layer 25. By peening the surface layer of the deposited portion 25 on which the oxide film 26 is formed, the residual tensile stress can be removed, and the slidability and mechanical characteristics can be further improved.

Specific examples of the peening treatment include shot peening, laser peening, and WPC. These methods are a kind of surface modification technique for improving various characteristics of a member surface by injecting metal or ceramic particles onto the member surface or irradiating a laser. In the present embodiment, peening is performed by causing particles to collide with the surface layer of the deposition layer 25 by shot peening or WPC.
In the manufacturing method of the present embodiment, for example, particles are injected toward the deposition layer 25 at a speed of 50 m / sec or higher or an injection pressure of 3 kg / cm ² . The hardness of the particles to be ejected is equal to or higher than the hardness of the deposited layer 25 of the present embodiment. As such particles, powders in which metal, silica beads, glass beads, ceramics, or the like are formed into particles can be used. In the peening process in the manufacturing method of the present embodiment, the aforementioned particles continuously collide with the deposited layer 25, and the residual compressive stress is applied by the impact force, and as a result, the residual tensile stress is removed. Further, when the particles collide, the temperature of the deposited layer 25 and the oxide film 26 on the surface of the deposited layer 25 rises, and after the temperature becomes microscopically high, it is rapidly cooled. Thus, the composition of the deposited layer 25 and the oxide layer 26 is refined, the voids are reduced, and the bonds between crystals are strengthened.

In the manufacturing method of this embodiment, the cracking resistance and the erosion resistance can be improved by performing a peening treatment. By the peening treatment, microcracks on the surface generated by the pulse discharge treatment can be repaired. Therefore, according to the manufacturing method of the present embodiment, the steam turbine equipment member 1 having high hardness, excellent toughness, and excellent mechanical characteristics can be obtained. Moreover, since the member 1 for steam turbine equipment obtained by the manufacturing method of this embodiment has high hardness and excellent mechanical characteristics, it is particularly suitable for a member having a sliding portion.
In this embodiment, the peening process is performed after S106 in FIG. 3, but the present invention is not limited to this. The same effect can be obtained even after S104 or S105 in FIG. 3, that is, after the deposition layer 25 is formed.

(Modification 1 of 3rd Embodiment)
In this modification, the particles used in the peening process described above are Cr or Cr compounds. In this modification, it is possible to improve the characteristics of the processed part by utilizing the normal temperature diffusion phenomenon caused by the heat generated when colliding with the processed part. The part where the particles collide becomes extremely hot locally and becomes active. At that time, the collided particles and the composition of the surface layer of the treated part react and adsorb and bond. As a result, the particles can be diffused and penetrated into the portion to be processed. In the diffusion phenomenon, lattice diffusion in which the elements constituting the metal member 10 and the diffusing elements form a solid solution, such as Fe (C) that can be solidified in the Fe lattice, is formed in the crystal lattice. There are grain boundary diffusion (diffusion that proceeds along the crystal grain boundary) and surface diffusion (diffusion that proceeds along the surface).

  In the manufacturing method of this modification, peening is performed using particles to be injected as particles of Cr or Cr compounds. Therefore, due to the normal temperature diffusion phenomenon, Cr and Cr compounds can be abundantly present in the surface layer portion of the deposited layer 25 which is the processing target portion. Therefore, it is possible to form the oxide film 26 having better oxidation resistance and protection by subjecting the deposited layer 25 rich in Cr to heat oxidation.

(Modification 2 of the third embodiment)
In this modification, in the third embodiment, metal, a metal compound, ceramic powder, or the like is injected into a minute hole of the porous deposition layer 25 and interposed. Then, the deposited layer 25 containing the inclusions is subjected to heat oxidation treatment by the same means as that shown in the first or second embodiment. The oxide film 26 can be formed by heat treatment. In this way, it is possible to form the steam turbine equipment member 1 having more excellent oxidation resistance and protection.

(Fourth embodiment)
Next, a steam control valve according to a fourth embodiment will be described. The steam control valve of this embodiment is configured by using the steam turbine equipment member 1 manufactured by the manufacturing method of the first embodiment. In the following description, elements that are the same as those in the first embodiment are denoted by the same reference numerals, and redundant descriptions are omitted.

  As shown in FIG. 5, the steam control valve 3 used in the front stage of the high-pressure turbine includes a steam valve main body 200, a bush 201, an upper lid 202, a valve seat 203 as a steam outlet, a valve body 204, a valve rod 205, steam An opening 207 which is an inlet for the steam, an opening 208 which is an outlet for steam, an opening 209 which is an insertion port for the valve rod 205 and the valve body 204.

  The steam valve main body 200 includes an opening 207 that is an inlet of steam, a valve seat 203 that is an outlet from which the steam that flows in from the opening 207 flows out, an opening 209 that is provided to face the valve seat 203, A steam chamber 210 which is a space provided in the center is provided.

  A valve seat 203 is provided in the steam chamber 210 of the steam valve main body 200. The valve seat 203 is provided with an opening 208 serving as a steam outlet. The opening 208 allows the steam to flow out from the steam valve main body 200.

  In the steam valve main body 200, the valve body 204 opens and closes the opening 208 (outlet) of the valve seat 203 by the axial movement of the valve rod 205 inserted into the steam chamber 210 through the opening 209.

  The upper lid 202 is fixed to the upper part of the opening 209 of the steam valve main body 200 and closes the upper surface of the steam valve main body 200. The upper lid 202 is provided with a through-hole penetrating in the vertical direction and continues to the opening 209. A hydraulic drive mechanism 206 is supported above the upper lid 202. A valve stem 205 is supported (connected) downward (vertically) by the hydraulic drive mechanism 206.

  The valve rod 205 is reciprocated up and down by a hydraulic drive mechanism 206. In the case of this example, since the through hole of the upper lid 202 becomes a sliding surface with the valve rod 205, a cylindrical bush 201 made of a metal resistant to friction is inserted into this portion.

  The bush 201 and the upper lid 202 are collectively referred to as a valve stem support portion. This valve stem support portion is provided above the opening 209 of the steam valve main body 200 so as to surround the valve stem 205. The valve stem support portion supports (guides) the valve stem 205 that moves in the axial direction so that it does not shake sideways.

  That is, the steam control valve 3 causes steam from the boiler to flow In into the steam chamber 210 through the opening 207, and the hydraulic drive mechanism 206 performs an operation (reciprocating operation) to lift or push the valve body 204 at the tip of the valve rod 205. As a result, the opening 208 of the valve seat 203 opens and closes, and the outflow of steam from the steam chamber 210 is controlled.

  The valve body 204 is provided so as to contact the valve seat 203 and open and close the opening of the valve seat 203. The valve body 204 is provided at the tip of a valve rod 205 inserted into the through hole of the upper lid 202 inside the steam valve main body 200.

  In the steam control valve 3 having such a structure, when the valve rod 205 is driven in the vertical direction by the hydraulic drive mechanism 206, the valve body 204 comes into contact with or separates from the valve seat 203 to open and close the steam flow path, The rotation speed of the high-pressure turbine is controlled by controlling the amount of steam flowing to the high-pressure turbine.

  The valve body 200, the bush 201, the valve body 204, the valve rod 205, the upper lid 202, and the like that are in contact with the high-temperature steam sent from the boiler are manufactured by the manufacturing method according to the first embodiment, and the parts and surfaces that are in contact with the high-temperature steam are oxidized. A film 26 (initial oxide film) is formed.

  According to the steam control valve 3 of this embodiment, since it is configured using the steam turbine equipment member 1 according to the first embodiment, a dense and rigid structure can be obtained, and destruction and erosion are prevented. be able to. Moreover, since generation | occurrence | production of an oxide scale is prevented, while being able to make the space | interval of each member of the steam control valve 3 small, a space | interval can be managed and this space | interval can be kept appropriate for a long period of time. In particular, when the bush 201 and the valve stem 205 are the steam turbine equipment member 1 of the present embodiment, the amount of steam leakage from the gap can be reduced to provide a highly efficient and reliable valve device. When the steam turbine equipment member 1 according to the first embodiment is applied to the member of the steam control valve 3 having these sliding portions, the slidability is not deteriorated due to generation of oxide scale. In addition, by applying the steam turbine equipment member 1 of the first embodiment using Cr or a metal containing Cr as the electrode material 22 to a member having a sliding portion, the slidability can be improved. . When a Co (cobalt) -based hard alloy is used as the electrode material 22, the steam control valve 3 of the present embodiment is not broken or eroded even on sliding surfaces such as the valve stem 205 and the bush 201 that are likely to be eroded. Can be provided.

  Further, the turbine equipment member 1 of the present embodiment using the electrode material 22 containing a large amount of Si as a member having fitting parts such as the steam valve main body 200, the bush 201, the upper lid 202, the valve seat 203, and the valve body 204. Thus, the steam control valve 3 having excellent erosion resistance can be obtained. Around these fitting parts, the flow velocity is fast and the environment is erosion. Due to erosion, an oxide scale is likely to be generated in a minute gap of the fitting portion, and the disassembling work at the regular inspection becomes difficult. By configuring the member having the fitting portion with the steam turbine equipment member 1 of the first embodiment in which the oxide film 26 having a Si content of 1 to 20% by weight is formed, oxidation resistance and erosion resistance A steam turbine member having the following can be obtained.

In addition, although the steam control valve 3 of this embodiment was comprised using the member 1 for steam turbine equipment manufactured with the manufacturing method of 1st Embodiment, it is not limited to this. You may comprise the steam control valve 3 using the member 1 for steam turbine equipment manufactured by the manufacturing method of 2nd, 3rd embodiment.
Moreover, although the steam control valve 3 is demonstrated here, the other steam turbine steam which has the operation | movement and function similar to the steam control valve 3 using the member 1 for steam turbine equipment which concerns on 1st Embodiment. It goes without saying that the same effect can be obtained even if the valve is configured.

(Fifth embodiment)
Next, a steam turbine according to a fifth embodiment will be described. The steam turbine of this embodiment comprises a steam turbine using the member 1 for steam turbine equipment manufactured with the manufacturing method of 1st Embodiment. In the following description, elements that are the same as those in the first embodiment are denoted by the same reference numerals, and redundant descriptions are omitted.

  As shown in FIG. 6, the steam turbine 4 includes a double-structure casing that includes an inner casing 320 and an outer casing 321 provided outside the inner casing 320. Further, a turbine rotor 323 in which a moving blade 322 is planted in the inner casing 320 is penetrated. The turbine rotor 323 is rotatably supported by a rotor bearing 324.

  On the inner side surface of the inner casing 320, stationary blades 325 are disposed so as to alternate with the moving blades 322 in the axial direction of the turbine rotor 323. Between the turbine rotor 323 and each casing, ground labyrinth portions 326a, 326b, 326c, and 326d are provided in order to prevent leakage of steam, which is a working fluid, to the outside.

  As shown in FIG. 6, a nozzle box 327 is provided at the inlet portion 320 a of the inner casing 320. The nozzle box 327 is disposed between the inner casing 320 and the turbine rotor 323 (that is, the inner portion of the inlet portion 320a of the inner casing 320), and the first stage stationary blade 325 (first stage) is disposed at the outlet portion of the nozzle box 327. Nozzle). The steam supplied to the nozzle box 327 passes through the first stage stationary blade 325 and is guided to the first stage moving blade 322.

  Between the inlet part 321a of the outer casing 321 and the inlet part 320a of the inner casing 320, an inlet sleeve pipe 340 that functions as a steam inlet pipe is provided. The inlet sleeve tube 340 guides the steam from the main steam tube 328 into the nozzle box 327.

  The steam turbine 4 flows in a steam passage in the inner casing 320 while performing expansion work, and an exhaust flow that guides steam, which is a working fluid that has passed through the rotor blade 322 in the final stage, from the inside of the inner casing 320 to the outside of the steam turbine 4. A road 329 is provided.

In the steam turbine 4 of this embodiment, the inner casing 320, the moving blade 322, the turbine rotor 323, the stationary blade 325, the ground labyrinth portions 326a, 326b, 326c, and 326d, the inlet sleeve tube 340, the exhaust passage 329, and the main steam tube 328 The member 1 for steam turbine equipment in which the oxide film 26 (initial oxide film) according to the first embodiment is formed in a component part that is in contact with high-temperature steam, such as, is used. Therefore, it is possible to provide a steam turbine that has excellent oxidation resistance, long life, and excellent maintainability. In particular, since high slidability can be obtained in components such as the moving blade 322, the turbine rotor 323, the stationary blade 325, and the ground labyrinth portions 326a, 326b, 326c, and 326d, a long-life steam turbine can be provided. it can.
Therefore, if the turbine equipment member 1 of the first embodiment is used, it is possible to provide a steam turbine that can be properly operated for a long period of time and has excellent maintainability.

Further, the rotor blade 322 and the stationary blade 325, which are likely to generate erosion, are configured by the steam turbine equipment member 1 according to the first embodiment using a Co (cobalt) -based hard alloy as an electrode material. It is possible to provide a steam turbine that is excellent in performance and has a long life and excellent maintainability.
Further, according to the manufacturing methods of the first to third embodiments, since the diffusion layer 12 and the deposition layer 25 are formed only in the portion where the discharge occurs, it can be locally formed in a desired portion. Therefore, it is possible to form the oxide film 26 only in parts where erosion is particularly likely to occur, such as the moving blade 322 and the stationary blade 325.

  If the rotor blade 322 and the ground labyrinth portion 326 that is a ground portion of high-pressure steam are configured by the turbine equipment member 1 of the first embodiment using the electrode material 22 containing a large amount of Si, excellent erosion resistance is achieved. A steam turbine having In these parts, the steam flow rate is high and erosion is particularly likely to occur. Erosion makes it easy to generate oxide scale in minute gaps, making disassembly work during periodic inspection difficult. A steam turbine having oxidation scale resistance and erosion resistance is formed by configuring the member with the steam turbine equipment member 1 according to the first embodiment in which the oxide film 26 having a Si content of 1 to 20% by weight is formed. Can be obtained.

In addition, although the steam turbine of this embodiment was comprised using the member 1 for steam turbine equipment manufactured by the manufacturing method of 1st Embodiment, it is not limited to this. You may comprise a steam turbine using the member 1 for steam turbine equipment manufactured by the manufacturing method of 2nd, 3rd embodiment.
In addition, the steam turbine equipment member 1 in which the oxide film 26 according to the first to third embodiments is formed is prevented from generating oxide scale even if the operation time elapses after being applied to the steam turbine. Therefore, as part of the member 1 for steam turbine equipment, the oxide film 26 according to the first embodiment is formed on each of the opposing fitting surfaces of a member having a narrow groove-like assembly structure such as a fitting portion. Thereby, the space | interval of the fitting part of the member 1 for steam turbine equipment can be kept appropriate for a long period of time. In addition, since the seizure phenomenon of the fitting portion due to the oxide scale can be eliminated, the disassembling work for each periodic inspection can be facilitated, and the maintainability can be improved.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Steam turbine equipment member, 2 ... Steam turbine equipment manufacturing apparatus, 3 ... Steam control valve, 4 ... Steam turbine, 10 ... Metal member, 20 ... Electrode, 30 ... Processing tank, 40 ... Processing liquid, 50 DESCRIPTION OF SYMBOLS ... Discharge detection part, 60 ... Control part, R ... Current limiting resistor, Tr ... Switching element, E ... DC power supply.

Claims (16)

A metal member made of a first metal material and having heat resistance;
A diffusion layer formed from the surface of the metal member to the inside, in which a second metal material different from the first metal material is diffused;
A porous deposition layer containing the second metal material on the surface of the metal member on which the diffusion layer is formed;
An oxide film formed on the surface of the deposited layer and made of an oxide of the second metal material;
A member for steam turbine equipment, comprising:   The member for steam turbine equipment according to claim 1, wherein the oxide film is formed on an outer surface of the deposited layer and a hole wall surface in the deposited layer.   The said 2nd metal material contains 1 or more types of metals chosen from Co (cobalt), Ni (nickel), Fe (iron), Cu (copper), and Al (aluminum). Or the member for steam turbine equipment of 2.   The second metal material includes one or more selected from Co (cobalt), Cr (chromium), Ni (nickel), Mo (molybdenum), W (tungsten), and Si (silicon). The member for steam turbine equipment according to any one of claims 1 to 3.   The said 2nd metal material contains Co (cobalt) 30weight% or more, Cr (chromium) 10weight% or more, and Ni (nickel) 20weight% or less, The any one of Claim 1 thru | or 4 characterized by the above-mentioned. The steam turbine equipment member according to claim 1. The oxide film includes at least one of Cr ₂ O ₃ and SiO ₂ ;
The member for steam turbine equipment according to claim 1, wherein the deposited layer contains Fe and 1 to 20 wt% of Si.   The member for a steam turbine equipment according to any one of claims 1 to 6, wherein a thickness of the deposited layer is 5 to 10 [µm]. A steam chamber,
An inlet portion formed on the wall surface of the steam chamber for receiving steam;
An outlet that is formed on the wall surface of the steam chamber and discharges the steam;
A valve seat formed at the outlet,
A through-hole formed in the wall surface of the steam chamber facing the outlet portion;
A valve stem inserted into the steam chamber through the through hole;
A valve body disposed at an end of the valve stem and corresponding to the valve seat for opening and closing the valve seat;
A steam control valve comprising: a steam turbine equipment member according to any one of claims 1 to 7; and a bush disposed in the through hole and in sliding contact with the valve rod. A turbine rotor,
A moving blade comprising the steam turbine equipment member according to any one of claims 1 to 7 and implanted in the turbine rotor;
A stationary blade comprising the member for a steam turbine facility according to any one of claims 1 to 7 and arranged alternately with the moving blade,
A steam turbine comprising a nozzle box for supplying steam to the moving blade and the stationary blade. A first member comprising the steam turbine equipment member according to any one of claims 1 to 7, having a fitting portion, and having the oxide film on a fitting surface of the fitting portion;
It consists of the member for steam turbine equipments of any one of Claims 1 thru | or 7, It has a fitting part fitted to a said 1st member, The said oxide film is provided in the fitting surface of the said fitting part. A second member to
A steam control valve characterized by comprising: A first member comprising the steam turbine equipment member according to any one of claims 1 to 7, having a fitting portion, and having the oxide film on a fitting surface of the fitting portion;
It consists of the member for steam turbine equipments of any one of Claims 1 thru | or 7, It has a fitting part fitted to a said 1st member, The said oxide film is provided in the fitting surface of the said fitting part. A second member to
A steam turbine comprising: Holding a metal member made of a first metal material having heat resistance and an electrode made of a second metal material different from the first metal material, with a gap therebetween;
A voltage is applied to the metal member and the electrode to generate a discharge in the gap, thereby forming a deposited layer having the second metal material on the surface of the metal member and the second in the metal member. A diffusion layer in which the metal material is diffused,
A method for manufacturing a member for steam turbine equipment, comprising forming an oxide film made of an oxide film of the second metal material on a surface of the deposited layer.   The method of manufacturing a member for a steam turbine equipment according to claim 12, wherein the electrode is formed by heating or compressing the powder of the second metal material or the powder of the second metal material compound.   The method for manufacturing a member for a steam turbine equipment according to claim 12 or 13, wherein the oxide film is formed by heating the deposited layer at a temperature equal to or lower than a tempering temperature of the first metal material.   The method for manufacturing a member for a steam turbine equipment according to any one of claims 12 to 14, wherein the electrode further contains one or more selected from C (carbon) and N (nitrogen).   16. The method for manufacturing a member for a steam turbine equipment according to claim 12, wherein the deposited layer is further peened.

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