JP2011074797A - Blade, manufacturing method therefor, and rotary machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blade having excellent erosion resistance and fouling resistance in such an environment as contacting with gas directly. <P>SOLUTION: The blade is equipped with a blade-shaped base 13, a hard material layer 20 composed of a hard material and provided in a first range A1 at the uppermost layer being part of the surface of the base 13, and a fouling resisting material layer 21 composed of a fouling resisting material and provided in a second range A2 at the uppermost layer except the first range A1 on the surface of the base 13. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a blade having a blade shape, a method for manufacturing the blade, and a rotary machine including the blade.

  Conventionally, for example, blades used in rotating machines such as steam turbines, compressors, and pumps have been subjected to surface treatment in consideration of heat resistance, corrosion resistance, and the like. For example, in a steam turbine, steam, which is a working fluid, is driven by being jetted onto the moving blades of the turbine, and blades such as moving blades and stationary blades are in direct contact with the steam. In addition, a compressor that is used in a chemical plant or the like and compresses various fluids receives power from the outside and rotates a blade to compress the fluid. Even in such a compressor, the blade directly contacts the gas. Here, there is a problem that erosion wear occurs on the surface due to the water droplets contained in the gas colliding with the blade at high speed. When such erosion wear occurs, the blade vibrates, and the vibration may damage the component.

In the blade used in the rotating machine as described above, a so-called fouling phenomenon may occur in which ceramic components such as SiO ₂ contained in the gas adhere. Thus, when a ceramic component adheres to the blade, there is a problem that the efficiency of the entire apparatus is lowered because the operation efficiency is lowered due to the change in the blade shape.

  As a countermeasure for preventing the erosion wear and fouling, a method of coating a film for suppressing the above phenomenon on the surface of the substrate is generally employed. For example, as a measure for suppressing the erosion wear, a hard film 103a, 103b having a laminated structure as shown in FIGS. 24A and 24B and made of TiN, CrN or the like is formed by physical vapor deposition. There is known a technique of forming on a substrate 101 by a (PVD: Physical Vapor Deposition) method and further forming an intermediate layer 102 made of Cr or the like as necessary (for example, see Patent Document 1). In addition, it is known that overlay welding of Stellite (registered trademark) is performed, and that a hard film 104 made of WC-NiCo or the like is formed on the substrate 101 by thermal spraying as shown in FIG. (For example, refer to Patent Documents 2 and 3).

  On the other hand, as a countermeasure for preventing the fouling, for example, as shown in FIG. 25 (a), fluorine resin particles 111b are formed by dispersing fluorine resin particles 111b in a plating 111a on a substrate 110. Techniques for forming the plating film 111 have been proposed (see, for example, Patent Documents 4 and 5). Further, as shown in FIG. 25 (b), in addition to the method of coating the fluororesin layer 113 in which the ceramic particles 113b are dispersed in the fluororesin 113a via the sprayed layer 112 on the base 110, the fluororesin 113 is used. A technique for forming a thermallon coating which is a resin-based film is also known (see, for example, Patent Document 6).

Further, as a fouling prevention measure, in addition to the above, in gas equipment parts, a method of coating a fluororesin on a base material (see, for example, Patent Document 7) or fluorine with reduced surface energy is contained. A method for forming a film on a substrate (for example, see Patent Document 8), a method for smoothing a hard nitride film on a substrate and reducing physical adsorption (for example, see Patent Document 9), etc. have been proposed. Yes.
However, since the film having the fouling resistance as described above is soft and has low erosion resistance, there is a problem that the film peels in an environment where erosion such as direct contact with gas is likely to occur. there were.

Japanese Patent Publication No.8-30264 JP 2004-27289 A JP 2003-27206 A JP 2007-71031 A JP 2007-71032 A JP 2006-291307 A JP 2004-283699 A JP 2007-213715 A JP 2007-162613 A

However, the erosion-resistant hard coatings as described in Patent Documents 1 to 3 do not have fouling resistance, so that the erosion resistance is improved, but the fouling resistance is low. was there.
On the other hand, since the film having the fouling resistance as described in Patent Documents 4 to 9 is soft and has a low erosion resistance, the film does not form in an environment where erosion such as direct contact with gas is likely to occur. There was a problem of peeling.
For this reason, in blades used in an environment where both erosion and fouling occur, it is not possible to ensure fouling resistance when attempting to ensure erosion resistance, but ensure fouling resistance. There has been a problem that erosion resistance cannot be ensured.

  The present invention has been made in view of the above-described circumstances, and provides a blade excellent in erosion resistance and fouling resistance in an environment in direct contact with gas.

In order to solve the above problems, the present invention proposes the following means.
The blade of the present invention includes a wing-shaped base material, a hard material layer made of a hard material provided in the uppermost layer in a first range that becomes a part on the surface of the base material, and a surface of the base material. And a fouling-resistant material layer made of a fouling-resistant material provided in the uppermost layer in a second range other than the first range.

  The blade manufacturing method of the present invention includes a hard material layer forming step of forming a hard material layer made of a hard material in at least a first range that is a part on the surface of a wing-shaped base material, and the base A fouling-resistant material layer forming step of forming a fouling-resistant material layer made of a fouling-resistant material as the uppermost layer in the second range other than the first range on the surface of the material. Yes.

  According to this configuration and method, in the first range, since the hard material made of the hard material is formed in the uppermost layer on the surface of the base material, the progress of erosion can be suppressed. On the other hand, on the surface of the base material, in the second range, a fouling-resistant material layer made of a fouling-resistant material is formed on the uppermost layer, so that fouling occurs in which mixed components contained in the gas adhere. To be suppressed. For this reason, the range where the occurrence of erosion is dominant on the substrate surface is the first range, and the range where the occurrence of fouling is dominant is the second range, thereby ensuring both erosion and fouling. Can be prevented.

  Further, in the above blade, the hard material layer is formed on each of the first range and the second range on the surface of the base material, and the fouling-resistant material layer includes the second anti-fouling material layer. It is preferable that the upper layer is formed above the hard material layer.

  In the blade manufacturing method, the hard material layer forming step forms the hard material layer in the first range and the second range, and the fouling resistant layer forming step includes the hard material layer forming step. It is preferable to form the anti-fouling material layer above the material layer.

  According to this configuration and method, after the hard material layer is formed in the hard material layer forming step, the anti-fouling material layer is formed in an upper layer than the hard material layer in the anti-fouling material layer forming step. . For this reason, in the hard material layer forming step, not only the first range but also the hard material layer may be formed on the entire substrate surface, and the hard material layer can be easily formed.

  In the blade, the anti-fouling material layer is formed in the vicinity of the boundary between the first range and the second range so that the thickness gradually decreases toward the boundary. Is preferred.

  According to this configuration, a smooth surface without a step is formed in the vicinity of the boundary between the first range and the second range by forming the anti-fouling material layer so that the thickness gradually decreases toward the boundary. It can be. For this reason, it can prevent that stress concentration arises by the level | step difference of a surface, and peeling of a fouling-proof material layer will be induced.

  In the blade manufacturing method, the anti-fouling material layer forming step includes a first step of forming the anti-fouling material layer in both the first range and the second range, It is preferable to have a second step of removing the anti-fouling material layer formed in the first range.

  According to this method, in the first step, the anti-fouling material layer can be easily formed by forming it on the entire surface of the base material, while in the first step, By removing the anti-fouling material layer, the hard material layer can be exposed as the uppermost layer in the first range.

  In the blade manufacturing method, the second step is preferably performed by spraying a granular abrasive on the anti-fouling material layer and performing a polishing process.

  According to this method, only the anti-fouling material layer that needs to be removed can be easily removed by spraying the abrasive material and removing the anti-fouling material layer by the polishing process.

  In the blade manufacturing method, the direction in which the abrasive is sprayed on the base material in the second step is substantially the same as the relative direction of the fluid flowing around the blade to be manufactured when the blade is used. It is preferable to set so as to.

  According to this method, by setting the spraying direction of the abrasive to the base material so as to substantially coincide with the relative direction of the fluid flowing around the blade to be manufactured during use, the abrasive is eroded. It sprays on the range which is easy to generate | occur | produce, a fouling-proof material layer can be removed as a 1st range, and a hard material layer can be exposed. Further, erosion is less likely to occur and fouling is likely to occur from a range where erosion is likely to occur, that is, the polishing effect by the abrasive gradually weakens in the vicinity of the boundary between the first range and the second range. For this reason, by forming the anti-fouling material layer so as to gradually become thinner from the second range toward the first range, a smooth surface without a step can be obtained. As a result, it is possible to prevent stress concentration from occurring due to a step on the surface and induce peeling of the anti-fouling material layer.

  In the blade manufacturing method, the second step includes attaching the base material to the shaft body in a direction similar to the direction in which the blade to be manufactured is attached to the rotation shaft, and rotating the shaft body. However, it is preferable to carry out.

  According to this method, it is possible to remove the fouling-resistant material layer in a portion where erosion is likely to occur by spraying the abrasive in a state closer to the time of use. Moreover, by attaching a plurality of base materials to the shaft body, the second step can be performed simultaneously on a plurality of objects, which is efficient.

  In the blade manufacturing method, the second step includes a rough polishing process in which a polishing process is performed with a large particle diameter of the abrasive, and a particle diameter of the abrasive after the rough polishing process. It is preferable to include a final polishing process in which the polishing process is performed with a smaller one than that during the polishing process.

  According to this method, in the second step, the polishing process can be effectively performed in a short time by performing the polishing process with the abrasive having a large particle diameter as the rough polishing process. Further, by performing the polishing process with a small abrasive particle size as the final polishing process, the surface of the hard material layer exposed in the first range, and the resistance in the vicinity of the boundary between the first range and the second range. The surface of the fouling material layer can be finished more smoothly.

  In the above blade, the hard material layer has a layer thickness in the first range substantially equal to the sum of the layer thickness in the second range and the layer thickness of the anti-fouling material layer. Thus, it is preferable that the layer thickness of the first range and the second range is set.

  Further, in the blade manufacturing method, after the hard material layer forming step, the hard material layer in the second range is replaced with the anti-fouling material that is planned in the anti-fouling material layer forming step. It is preferable to provide a hard material layer removing step of removing only the thickness of the material layer.

  According to this configuration and method, the surface of the hard material layer in the first range and the surface of the anti-fouling material layer in the second range are formed on a smoother surface without causing a step. It is possible to prevent stress concentration from occurring due to the level difference on the surface and to induce peeling of the anti-fouling material layer. Further, since the unevenness on the surface is reduced, it is possible to suppress the resistance generated between the surface and the fluid during use, and it is possible to realize a higher performance blade.

A rotating machine according to the present invention includes the blade described above.
According to this configuration, it is possible to improve durability and performance by effectively suppressing the occurrence of erosion and fouling.

According to the blade of the present invention, erosion resistance and fouling resistance in an environment in direct contact with gas can be improved.
In addition, according to the blade manufacturing method of the present invention, it is possible to provide a blade having excellent erosion resistance and fouling resistance in an environment in direct contact with gas.
Further, according to the rotating machine of the present invention, it is possible to improve durability and performance.

It is a perspective view which shows the detail of the rotor part of the steam turbine of the 1st Embodiment of this invention. It is a perspective view which shows the detail of the steam turbine blade of the 1st Embodiment of this invention. It is sectional drawing seen from the height direction of the steam turbine blade of the 1st Embodiment of this invention. FIG. 4 is a cross-sectional view showing details of a layer structure at a portion E in FIG. 3 in the steam turbine blade of the first embodiment of the present invention. FIG. 4 is a cross-sectional view showing details of the layer structure at a portion F in FIG. 3 in the steam turbine blade of the first embodiment of the present invention. FIG. 4 is a cross-sectional view showing details of a layer structure at a G part in FIG. 3 in the steam turbine blade of the first embodiment of the present invention. (A) is a graph which shows the relationship between the fluorine content rate in a fouling-resistant material layer, and a silica particle adhesion amount, (b) is a graph which shows the relationship between the fluorine content rate in a fouling-resistant material layer, and hardness. It is. It is a flowchart which shows the manufacturing method of the steam turbine blade of the 1st Embodiment of this invention. It is explanatory drawing explaining the 2nd step of the fouling material layer formation process in the manufacturing method of the steam turbine blade of the 1st Embodiment of this invention. It is a figure explaining typically the steam turbine blade of a 1st embodiment of the present invention, (a) shows the case where the steam turbine blade of a 1st embodiment is used, and (b) shows only erosion resistance. (C) shows the continuous operation time, the amount of wear, and the fouling for the steam turbine blade of Comparative Example 2 to which only the fouling resistance is imparted. It is the graph which showed the relationship with quantity. It is explanatory drawing explaining the 2nd step of the anti-fouling material layer formation process in the manufacturing method of the steam turbine blade of the modification of the 1st Embodiment of this invention. In the steam turbine blade of the 2nd Embodiment of this invention, it is sectional drawing which shows the detail of the layer structure in the boundary vicinity of the 1st range and the 2nd range. It is explanatory drawing explaining the hard material layer formation process in the manufacturing method of the steam turbine blade of the 2nd Embodiment of this invention. It is explanatory drawing explaining the hard material layer removal process in the manufacturing method of the steam turbine blade of the 2nd Embodiment of this invention. It is explanatory drawing explaining the state which the hard material layer removal process was completed in the manufacturing method of the steam turbine blade of the 2nd Embodiment of this invention. It is explanatory drawing explaining the 1st step of the anti-fouling material layer formation process in the manufacturing method of the steam turbine blade of the 2nd Embodiment of this invention. It is explanatory drawing explaining the 2nd step of the anti-fouling material layer formation process in the manufacturing method of the steam turbine blade of the 2nd Embodiment of this invention. It is sectional drawing which shows the detail of the layer structure in the boundary vicinity of the 1st range and the 2nd range in the steam turbine blade of the 3rd Embodiment of this invention. It is explanatory drawing explaining the hard material layer formation process in the manufacturing method of the steam turbine blade of the 3rd Embodiment of this invention. It is explanatory drawing explaining the hard material layer formation process in the manufacturing method of the steam turbine blade of the 3rd Embodiment of this invention. It is explanatory drawing explaining the fouling-proof material layer formation process in the manufacturing method of the steam turbine blade of the 3rd Embodiment of this invention. It is explanatory drawing explaining the fouling-proof material layer formation process in the manufacturing method of the steam turbine blade of the 3rd Embodiment of this invention. It is explanatory drawing explaining the fouling-proof material layer formation process in the manufacturing method of the steam turbine blade of the 3rd Embodiment of this invention. It is a figure explaining the conventional steam turbine blade, and is a schematic cross section which shows the laminated structure in which each membrane | film | coat was formed on the base material. It is a figure explaining the conventional steam turbine blade, and while showing the laminated structure in which each membrane | film | coat was formed on the base material, it is a schematic cross section which shows the enlarged view of the outermost surface.

(First embodiment)
A first embodiment according to the present invention will be described below with reference to the drawings.
For example, in the steam turbine 1 shown in FIG. 1, a plurality of steam turbine blades 10 according to the present invention are arranged radially on the rotor 2 as rotor blades (see the steam turbine blades 10 in the figure), and in the axial direction. It is a part for a rotating machine that is used with multiple stages. In the steam turbine 1, steam, which is a working fluid, is jetted onto the steam turbine blades 10 (moving blades) to rotationally drive the rotor 2. In such a steam turbine 1, the steam turbine blades 10 directly It is configured to come into contact with steam.

Next, the details of the structure of the steam turbine blade 10 will be described.
As shown in FIG. 2, a platform 11 is attached to the base end of the steam turbine blade 10, and a blade root 12 is provided on the back side of the platform 11 opposite to the surface side on which the steam turbine blade 10 is attached. The provided steam turbine blade 10 is integrated with the rotor 2 by the blade root 12 being attached to the rotor 2 side. As shown in FIG. 3, the steam turbine blade 10 has an abdominal surface portion 10a formed in a concave shape and a back surface portion 10b formed in a convex shape facing the abdominal surface portion 10a, and the abdominal surface portion 10a and the back surface portion. 10b is formed into a so-called wing shape formed so that the thickness gradually increases from the front edge 10c toward the intermediate portion and gradually decreases from the intermediate portion toward the rear edge 10d.

  In addition, the steam turbine blade 10 includes a wing-shaped base material 13, a first coating 14 that covers the first range A <b> 1 among the surfaces of the base material 13, and a first of the surfaces of the base material 13. And a second film 15 covering the second range A2 excluding the range A1. As the base material 13, for example, a material generally used in this field such as stainless steel including SUS410J1 can be used without any limitation, and can be appropriately selected.

  Here, the first range A1 is a range in which the generation of erosion is dominant during actual use in the steam turbine blade 10, and specifically, the rear surface 10a including the front edge 10c on the front edge 10c side to the back surface. This is a partial range up to the portion 10b. In such a range, moisture (drain) such as vapor contained in the gas collides at a high speed, so that erosion is likely to occur. Further, the second range A2 is a range in which generation of fouling is dominant in actual use in the steam turbine blade 10, and specifically, a part from the abdominal surface portion 10a including the rear edge 10d to the back surface portion 10b. Range. In such a range, although erosion is unlikely to occur, fouling is likely to occur due to adhering components such as ceramic components such as silica contained in the gas. Note that, in the range set as the first range A1, even if a gas mixed component adheres, the deposit is removed by the high-speed collision of the drain, so that fouling hardly occurs. The size of the first range A1 and the second range A2 and the positions of the boundaries B1 and B2 are the shape of the steam turbine blade 10 and the rotation of the rotor 2 when applied to the steam turbine 1. It depends on the number and the steam flow rate. The boundaries B1 and B2 may be set so that positions on the periphery of the steam turbine blade 10 are different in the blade height direction perpendicular to the cross section shown in FIG.

  Next, the details of the layer structure of the first film 14 and the second film 15 will be described. FIG. 4 shows a portion E in FIG. 3 and shows a part of the first range A1. FIG. 5 shows a portion F in FIG. 3 and shows a part of the second range A2. FIG. 6 shows a G portion in FIG. 3 and shows the vicinity of the boundary between the first range A1 and the second range A2. As shown in FIG. 4, the first film 14 in the first range A1 has a hard material layer 20 made of a hard material formed on the surface 13a of the base material 13, and the hard material layer 20 is the uppermost layer. Is configured. As shown in FIG. 5, the second film 15 in the second range A <b> 2 includes a hard material layer 20 made of a hard material formed on the surface 13 a of the base material 13 and a hard material in the same manner as the first range A <b> 1. A fouling-resistant material layer 21 made of a fouling-resistant material formed on the surface 20a of the material layer 20, and the fouling-resistant material layer 21 constitutes the uppermost layer. Also, as shown in FIG. 6, in the vicinity of the boundaries B1 and B2 between the first range A1 and the second range A2, the anti-fouling material layer 21 is gradually thinner toward the boundaries B1 and B2. It is formed to become.

  The hard material is required to be a material having high erosion resistance and high adhesion to the lower layer. For example, a ceramic material is selected, and it is preferably made of any material of nitride, carbide, boride, or oxide. Among these materials, it is more preferable that the material is at least one of TiN, TiAlN, CrN, TiC, TiCN, and ZrN. The layer thickness of the hard material layer 20 is preferably in the range of 1 to 30 μm. When the layer thickness of the hard material layer 20 is less than 1 μm, it is difficult to obtain the effect of improving the erosion resistance, and when the layer thickness exceeds 10 μm, the stress in the layer is increased and peeling is likely to occur. The process time during film formation becomes longer. The layer thickness of the hard material layer 20 is more preferably in the range of 3 to 20 μm, and further preferably in the range of 5 to 15 μm.

  The anti-fouling material is required to be a material having high fouling resistance. Specifically, a fluorine-containing material, for example, a diamond-like carbon (hereinafter referred to as DLC) containing fluorine is selected. In such a fluorine-containing DLC, not only excellent fouling resistance but also a steam turbine is used. It is possible to obtain strength and wear resistance according to actual use conditions. DLC is generally used as a material for parts and the like that require high strength and wear resistance. However, when the DLC contains fluorine, the fouling resistance is further imparted.

  Further, the anti-fouling material layer 21 is preferably made of DLC whose fluorine concentration is in the range of 10 to 40% by mass. When the fluorine concentration in the anti-fouling material layer 21 is less than 10% by mass, the energy of the surface 13a becomes high, and it becomes difficult to obtain the effect of improving the anti-fouling property that reduces the amount of silica particles and the like. It becomes difficult to extend the cycle for a long time. In this case, for example, the amount of adhesion is half or more than that of a conventional film made of TiN, and there is a possibility that a large reduction effect cannot be obtained. Further, in the anti-fouling material layer 21, when the fluorine concentration exceeds 40% by mass, the film hardness is less than 200 Hv and the hardness becomes insufficient, which may be unsuitable in an environment during actual use. Therefore, the anti-fouling material layer 21 is preferably made of DLC having a fluorine concentration in the range of 10 to 40% by mass, more preferably in the range of 15 to 38% by mass. More preferably, it is in the range of mass%. Note that the fluorine concentration is not necessarily uniform in the thickness direction of the anti-fouling material layer 21, and for example, the fluorine concentration may be gradually decreased from the surface 21a toward the inside. By doing in this way, the adhesiveness between lower layers can be improved.

  In the graph of FIG. 7A, the fouling resistance provided in the steam turbine blade 10 of the present embodiment when the silica particle adhesion amount measurement test (fouling resistance test) is performed by the method described in Patent Document 4 above. The relationship between the fluorine content (fluorine concentration) in the ring material layer 21 and the silica particle adhesion amount is shown (for the test method, refer to paragraphs 0064 to 0066 of JP-A-2007-71031). As shown in FIG. 7A, it can be seen that when the fluorine content in the anti-fouling material layer 21 is less than 10% by mass, the silica particle adhesion amount (fouling amount) becomes remarkable. Moreover, the graph of FIG.7 (b) shows the relationship between the fluorine content rate (fluorine concentration) in the anti-fouling material layer 21 with which the steam turbine blade 10 is equipped, and hardness. As shown in FIG.7 (b), when the fluorine content rate in the anti-fouling material layer 21 exceeds 40 mass%, hardness will be less than 200 Hv and intensity | strength will fall.

  The layer thickness of the anti-fouling material layer 21 is preferably in the range of 0.1 to 10 μm from the viewpoint that the fouling resistance can be effectively imparted to the steam turbine blade 10. If the layer thickness of the anti-fouling material layer 21 is less than 0.1 μm, fouling resistance is difficult to obtain, and if the layer thickness exceeds 10 μm, the stress in the layer may increase and cause peeling. In addition, the process time during film formation becomes longer. The layer thickness of the anti-fouling material layer 21 is more preferably in the range of 0.5 to 5 μm, and further preferably in the range of 0.8 to 3 μm.

Next, a method for manufacturing the blade of this embodiment will be described.
In the following description, as an example, the substrate 13 is assumed to be made of SUS410J1, the hard material layer 20 is made of TiN, and the anti-fouling material layer 21 is made of DLC containing fluorine, but is not limited thereto.
FIG. 8 is a flowchart showing manufacturing steps of the steam turbine blade 10 of the present embodiment. As shown in FIG. 8, the manufacturing method of the steam turbine blade 10 of this embodiment includes a preparation step S1 for processing the base material 13, a hard material layer forming step S2 for forming a hard material layer 20 made of a hard material, An anti-fouling material layer forming step S3 for forming an anti-fouling material layer 21 made of an anti-fouling material.
Details of each step will be described below.

First, as shown in FIG. 8, as a preparation step S1, the base material 13 is processed into a predetermined blade shape, and the surface 13a is mirror-finished. As the degree of mirror finishing, it is preferable that the surface roughness be 10-point average roughness, Rz = about 0.5 μm. In addition, as a raw material which processes the base material 13, a magnitude | size about 20 * 30 * 5 mm can be used, for example. Next, in this embodiment, the base material 13 is dried after being subjected to ultrasonic cleaning in alcohol, introduced into the sputtering apparatus, and the inside of the apparatus is vacuumed and decompressed to 3.0 × 10 ⁻³ Pa or less, After baking with a heater, it is preferable to perform a pretreatment for etching the surface 13a of the substrate 13 by further exposure to Ar plasma.

  Next, as shown in FIGS. 4 and 8, as the hard material layer forming step S2, the hard material layer 20 is formed over the entire surface 13a of the base material 13, that is, in both the first range A1 and the second range A2. Form. That is, a hard material made of TiN is formed on the surface 13a of the base material 13 by the sputtering method with the base material 13 disposed in the sputtering apparatus. At this time, Ti is used as a target, and nitrogen gas is used as a reaction gas. First, the temperature of the base material 13 is controlled to 300 ° C. by heater heating. Then, glow discharge is performed under conditions where the film forming power is about 1000 W, the flow rate of nitrogen flowing in the apparatus is about 10 sccm, the bias voltage of the base material 13 is about 100 V, and the power applied to the target is about 4000 W. A hard material layer 20 made of TiN is formed on the entire surface 13 a of the base material 13.

  Next, as shown in FIGS. 5 and 8, the anti-fouling material layer 21 made of fluorine-containing DLC is formed as the anti-fouling material layer forming step S3. In the present embodiment, the anti-fouling material layer forming step S3 is performed on the hard material layer 20 over the entire surface 13a of the base material 13, that is, both the first range A1 and the second range A2. The first step S3a for forming the layer 21 and the second step S3b for removing the anti-fouling material layer 21 formed in the first range A1 are included.

In the first step S3a, it is an ionized vapor deposition method in which a reactive gas is ionized by electron beam discharge and vapor-deposited, and a gas containing at least hexafluorobenzene gas (C6F6) is used as a reactive gas. The anti-fouling layer 21 is formed on the entire surface 21 a of the hard material layer 21. More specifically, the base material 13 on which the hard material layer 20 is formed on the surface 13a is introduced into an ionization vapor deposition apparatus, and the inside of the apparatus is depressurized by vacuum suction to 3.0 × 10 ⁻³ Pa or less. Then, in the ionization vapor deposition apparatus, hexafluorobenzene gas _{(C 6 F} 6), was introduced so that the pressure in the range of 2.0 to 6.5 × ¹⁰ -1 Pa, the ion source anode current value 0 The discharge is performed under conditions of about 4 A, the ion source filament current value is about 30 A, and the bias voltage value of the substrate 13 is about 1.5 kV. Thereby, the anti-fouling material layer 21 made of fluorine-containing DLC is formed on the entire surface 13a of the hard material layer 20. At this time, the fluorine concentration in the anti-fouling material layer 21 is uniform in the range of 10 to 40% by mass as described above, and can be, for example, about 30% by mass. Since such an ionized vapor deposition method is a method in which the amount and energy of ions can be freely controlled, a thin film made of fluorine-containing DLC can be formed with good controllability. In addition, by using hexafluorobenzene gas as a reaction gas at this time, the material ionized by the electron beam is efficiently formed on the substrate 13 as fluorine-containing DLC. In the above description, the anti-fouling material layer 21 is formed by the ionization vapor deposition method. However, the present invention is not limited to this. For example, the anti-fouling material layer 21 may be formed by the sputtering method similarly to the hard material layer 20 described above. good.

  As shown in FIG. 9, in the second step S <b> 3 b, a granular abrasive P is sprayed on the anti-fouling material layer 21 to polish the anti-fouling material layer 21 in the first range A <b> 1. Do. Specifically, after fixing the base material 13 on which the anti-fouling material layer 21 is formed with a predetermined jig, the granular abrasive P is sprayed toward the first range A1. The abrasive P is made of, for example, ceramic such as alumina or silica, has a diameter of about several μm to 100 μm, and preferably has a diameter of 10 μm or less from the viewpoint of smoothing the treated surface. Then, by blowing the abrasive P, the anti-fouling material layer 21 in the first range A1 is polished and removed by the abrasive P, and the lower hard material layer 20 is exposed as the uppermost layer. Will be.

At this time, as shown in FIG. 9, the spraying direction S of the abrasive P to the base material 13 is set so as to substantially coincide with the relative direction of the fluid flowing around the blade to be manufactured when it is used. Is preferred. In this way, the anti-fouling material layer 21 can be removed by the abrasive P in a state close to that erosion is caused by the fluid during actual use, and the erosion is effectively sprayed in a range where erosion is likely to occur. In the first range A1, the hard material layer 20 can be exposed by removing the anti-fouling material layer 21. Further, as shown in FIG. 6, the transition from a range where erosion is likely to occur to a range where erosion is unlikely to occur and fouling is likely to occur, that is, the boundary between the first range A1 and the second range A2 In the vicinity of B1 and B2, the polishing effect by the abrasive P is gradually weakened. For this reason, the anti-fouling material layer 21 can be formed so as to gradually become thinner from the second range A2 toward the first range A1, and a smooth surface 13a without a step can be formed.
In the second range A2, the anti-fouling material layer 21 can be maintained as it is without being removed by the abrasive 21. Note that, as with the spraying direction S, the spraying speed of the abrasive P is preferably set so as to substantially match the relative speed of the fluid flowing around the blade to be manufactured when it is used.

  In the steam turbine blade 10 of the present embodiment manufactured as described above and having the hard material layer 20 and the anti-fouling material layer 21, the hard material is the uppermost layer in the first range A1 of the surface 13a of the base material 13. Since the hard material layer 20 made of is formed, the progress of erosion can be suppressed. On the other hand, in the surface 13a of the base material 13, in the second range A2, the anti-fouling material layer 21 made of the anti-fouling material is formed in the uppermost layer, so that the mixed components contained in the gas adhere. Occurrence of fouling is suppressed. That is, in the surface 13a of the substrate 13, the range where the occurrence of erosion is dominant is the first range A1, the range where the occurrence of fouling is dominant is the second range A2, and the above layer configuration is provided. Both erosion and fouling can be reliably prevented. Accordingly, it is possible to realize the steam turbine blade 10 that is excellent in both fouling resistance and erosion resistance, has a long life, and has a low running cost. Such a steam turbine blade 10 is particularly effective as a middle blade of the steam turbine 1 in which both erosion and fouling can occur remarkably.

Here, based on the example described in FIG. 10, the operation and effect of the blade of this embodiment will be described.
FIG. 10 (a) shows the operating time and the amount of wear (erosion) when the steam turbine blade 10 of the example of the present embodiment is used for continuous operation after being mounted on the steam turbine 1 as shown in FIG. It is a graph which shows the relationship between the amount) and the fouling amount. FIG. 10B shows a case where the conventional steam turbine blade of Comparative Example 1 in which only the hard material layer 20 is formed on the base material 13 is mounted on the steam turbine and continuously operated as described above. FIG. 10C is a graph showing the characteristics when the conventional steam turbine blade of Comparative Example 2 in which only the anti-fouling material layer 21 is formed is used.

  As shown in the graph of FIG. 10B, in the case of Comparative Example 1 in which only erosion resistance is imparted, the occurrence state of fouling reaches an assumed reference value that requires a deposit inspection in a short continuous operation time. It turns out that it is a level. Further, as shown in the graph of FIG. 10 (c), in the case of Comparative Example 2 in which only fouling resistance is imparted, the expected reference value that requires the inspection of the wear amount (erosion amount) in a short continuous operation time. I can see that. For this reason, when these conventional steam turbine blades are used, it is obvious that the maintenance cycle for inspection and parts replacement is inevitably shortened, which causes the operating cost and the like to increase.

  On the other hand, as shown in the graph of FIG. 10A, the steam turbine blade 10 of the present embodiment is provided with both fouling resistance and erosion resistance. It can be seen that both the wear amount and the amount of wear reach a very long time until reaching an assumed reference value that requires inspection. Therefore, a maintenance cycle can be set in a long cycle, and it becomes possible to significantly reduce costs such as labor costs and parts costs. Therefore, in the steam turbine 1 provided with such a steam turbine blade 10, it is possible to improve durability by preventing erosion and preventing performance deterioration due to occurrence of fouling.

  Furthermore, in the steam turbine blade 10 of the present embodiment, the thickness gradually increases in the vicinity of the boundaries B1 and B2 between the first range A1 and the second range A2 as the fouling resistant material layer 21 moves toward the boundaries B1 and B2. By forming it to be thin, the stress concentration at the boundaries B1 and B2 can be relaxed as a smooth surface 13a having no step. For this reason, it can prevent that stress concentration arises by the level | step difference of the surface 13a, and peeling of the fouling-resistant material layer 21 is induced, and can improve durability further.

  In addition, as described above, in the manufacturing method, after forming the hard material layer 20 in the first range A1 and the second range A2 as the hard material layer forming step, the second range as the anti-fouling material layer forming step. By forming the anti-fouling material layer 21 on the hard material layer 20 only on A2, the hard material layer 20 is formed not only in the first range A1 but also on the entire surface 13a of the base material 13 in the hard material layer forming step. The hard material layer 20 can be easily formed.

  In the steam turbine blade 10 manufacturing method, in the anti-fouling material layer forming step, in the second step S3b, a rough polishing process in which a polishing process is performed with a large particle size of the polishing material P, and the rough polishing is performed. It is good also as what comprises the final polishing process which performs a grinding | polishing process by the thing with the particle diameter of the said abrasive | polishing material P smaller than the time of this rough polishing process after a process. Specifically, in the rough polishing process, a particle diameter of the abrasive P is about 50 μm to 100 μm, and in the final polishing process, the particle diameter of the abrasive P is smaller than 10 μm or less. To do. By doing so, the polishing process can be effectively performed in a short time as the rough polishing process, while the surface 13a of the hard material layer 20 exposed in the first range A1 as the final polishing process, the first range. The surface 21a of the anti-fouling material layer 21 near the boundaries B1 and B2 between A1 and the second range A2 can be finished more smoothly.

  Moreover, in 2nd step S3b, after fixing the base material 13 in which the anti-fouling material layer 21 was formed to the jig | tool, it shall spray from the predetermined spraying direction S, However, it is not restricted to this. FIG. 11 shows a modification of the manufacturing method of this embodiment. In the manufacturing method of this modified example, when the second step S3b of the anti-fouling material forming step S3 is performed, the steam turbine blade 10 is attached to the rotor 2 when the intermediate 24 completed up to the first step S3a is used. As described above, a plurality of radial members are attached to the shaft body 25. Then, the shaft body 25 is rotated, and the abrasive P is sprayed from the side that becomes the front edge 10 c toward the intermediate body 24. By doing in this way, the anti-fouling material layer 21 of the site | part which is easy to generate | occur | produce erosion by spraying the abrasives P in a state closer to actual use can be removed. Further, by attaching the plurality of intermediate bodies 24 to the shaft body 25, the second step S3b can be performed simultaneously on a plurality of objects, which is efficient.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. 12 to 17 show a second embodiment of the present invention. In this embodiment, the same members as those used in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 12, the steam turbine blade 30 of the present embodiment includes a base material 13, and a hard material layer 31 formed on the surface 13a of the base material 13 in the first range A1 and the second range A2, Although the surface 31a of the hard material layer 31 includes the anti-fouling material layer 21 formed in the second range A2, the layer thickness of the hard material layer 31 is different from that of the first embodiment. . Specifically, in the hard material layer 31, the layer thickness T1 in the first range A1 is substantially equal to the sum of the layer thickness T2 in the second range A2 and the layer thickness T3 of the anti-fouling material layer 32. Thus, the layer thicknesses T1, T2, and T3 of the first range A1 and the second range A2 are set. For this reason, the surface 31b of the hard material layer 31 that is the uppermost layer in the first range A1 and the surface 32a of the anti-fouling material layer 32 that is the uppermost layer in the second range A2 substantially coincide with each other without a step. .

Such a steam turbine blade 30 can be manufactured as follows.
First, similarly to the first embodiment, the base material 13 is processed as the preparation step S1.
Next, as shown in FIG. 13, the hard material layer 31 is formed in the first range A1 and the second range A2 as the hard material layer forming step S2. At this time, the layer thickness is formed as the layer thickness T1 of the hard material layer 31 finally formed in the first range A1.

Next, as the hard material layer removing step S4, a part of the hard material layer 31 in the second range A2 is removed.
That is, first, the mask 35 is formed on the surface 13a of the hard material layer 31 in the first range A1. Specifically, for example, a masking tape made of a rubber sheet having a thickness of about 1.5 mm is used as the mask 35, and this is adhered to the surface of the hard material layer 31 in the first range A1. Then, with the first range A1 covered with the mask 35, the hard material layer 31 in the second range A2 is polished by spraying the polishing material Q on the surface thereof, and is formed in a desired amount, that is, in the next step. The hard material layer 31 is removed from the surface by an amount substantially equal to the layer thickness T3 of the anti-fouling material layer 32. At this time, in the vicinity of the boundaries B1 and B2 between the first range A1 and the second range A2, polishing is performed by buffing so that the layer thickness gradually increases toward the first range A1. When the removal of the hard material layer 31 by the required thickness is completed in the entire second range A2, the state shown in FIG. 15 is obtained by removing the mask 35.

Next, the anti-fouling material layer 32 is formed as the anti-fouling material layer forming step S3.
That is, as shown in FIG. 16, as the first step S3a, the anti-fouling material layer 32 is formed in the first range A1 and the second range A2 by a predetermined layer thickness T3. At this time, the lower hard material layer 31 has a different thickness in the first range A1 and the second range A2, and an inclination or a step is generated at the boundaries B1 and B2. Therefore, the anti-fouling material layer 32 is also the same. In the boundary B1, B2, there is an inclination or a step.

  Next, as shown in FIG. 17, as the second step S3b, the abrasive P is sprayed on the first range A1 by the same method as that of the first embodiment, so that the anti-resistance formed in the first range A1. The fouling material layer 32 is removed. Thereby, in the first range A1, the hard material layer 31 below the anti-fouling material layer 32 is exposed as the uppermost layer.

  As described above, according to the steam turbine blade 30 and the manufacturing method thereof of the present embodiment, the surface 31b of the hard material layer 31 in the first range A1 and the surface of the anti-fouling material layer 32 in the second range A2. It is possible to form a smoother surface without causing a step between the gap 32a. For this reason, it can prevent that stress concentration arises by the level | step difference of the surfaces 31b and 32a between 1st range A1 and 2nd range A2, and peeling of the anti-fouling material layer 32 is induced. . Further, since the unevenness on the surface is reduced, the resistance generated between the surface and the fluid during use can be suppressed, and a higher performance blade can be realized.

  Further, as described above, in the present embodiment, the hard material layer 31 is formed so that the thickness of the hard material layer 31 gradually increases toward the first range A1 in the vicinity of the boundaries B1 and B2 in the hard material layer removing step S4. Thus, the anti-fouling material layer 32 is formed so that the layer thickness gradually decreases toward the first range A1. For this reason, it becomes difficult to produce a level | step difference in boundary B1, B2, it can prevent that peeling of the fouling-proof material layer 32 is induced, and can aim at the improvement of durability further.

(Third embodiment)
Next, a third embodiment of the present invention will be described. 18 to 23 show a third embodiment of the present invention. In this embodiment, the same members as those used in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 18 is a cross-sectional view of the vicinity of the boundaries B1 and B2 between the first range A1 and the second range A2 in the steam turbine blade 40 of the present embodiment. As shown in FIG. 18, the steam turbine blade 40 of the present embodiment includes a base material 13, a first film 41 covering the first range A <b> 1 of the surface 13 a of the base material 13, and the surface of the base material 13. 13a, and a second film 42 covering the second range A2. The first film 41 in the first range A1 has a hard material layer 45 made of a hard material formed on the surface 13a of the base material 13, and the hard material layer 45 constitutes the uppermost layer. The second film 42 in the second range A2 has a fouling-resistant material layer 46 made of a hard material formed on the surface 13a of the base material 13, and the fouling-resistant material layer 46 constitutes the uppermost layer. ing.

Next, the manufacturing method of the steam turbine blade 40 of this embodiment is demonstrated.
First, after carrying out the preparation step S1 as in the first embodiment, the hard material layer 45 is formed as the hard material layer forming step S2.
Here, as shown in FIG. 19, in the present embodiment, first, a mask 47 is formed on the surface 13a of the substrate 13 in the second range A2. The mask 47 is not particularly limited, but as described in the first embodiment, it is necessary to set the temperature of the base material 13 to a high temperature (for example, about 300 ° C.) as the hard material layer 45 is formed by sputtering. If there is, a heat-resistant masking tape is selected. And the mask 47 is formed by sticking this masking tape on the surface 13a of the base material 13 in 2nd range A2. Then, as shown in FIG. 20, a hard material layer 45 is formed in the first range A1 by a method such as sputtering, and then the mask 47 is removed.

Next, the anti-fouling material layer forming step S3 is performed.
First, as shown in FIG. 21, a mask 48 is formed on the surface 13a of the hard material layer 45 in the first range A1. As the mask 48, a mask similar to that used in the second embodiment is preferably selected. Further, in the vicinity of the boundaries B1 and B2 between the first range A1 and the second range A2, the edge 45a of the hard material layer 45 is retreated to the first range A1 side from the boundaries B1 and B2. The mask 48 is formed up to the position. The exposure amount of the edge 45a of the hard material layer 45 may be, for example, about 0.1 to 0.3 mm.

  Then, as shown in FIG. 22, the anti-fouling material layer 46 is formed in the second range A2. At this time, the mask 48 is formed only up to the position retracted to the first range A1 side from the boundaries B1 and B2, and the edge 45a of the hard material layer 45 is exposed, so that the boundaries B1 and B2 are exposed. In the vicinity, the anti-fouling material layer 46 is also formed on the hard material layer 45 as in the portion 46a.

  Then, as shown in FIG. 23, the surface near the boundaries B1 and B2 between the first range A1 and the second range A2 is finally polished as a finishing step S5 to finish the surface smoothly. Thereby, the part 46a of the anti-fouling material layer 46 formed on the edge 45a of the hard material layer 45 is removed in the anti-fouling material layer forming step S3.

  In the steam turbine blade 40 as described above, similarly to the first and second embodiments, the hard material layer 45 is formed as the uppermost layer in the first range A1, and the anti-fouling material layer 446 is formed in the second range. By being formed as the uppermost layer, it is possible to realize a steam turbine blade which is excellent in both fouling resistance and erosion resistance, has a long service life and low running cost. Further, in the steam turbine blade 40 of the present embodiment, the hard material layer 45 and the anti-fouling material layer 46 are not in a laminated relationship, and have a butt structure at the boundaries B1 and B2. Here, in the manufacturing method, the anti-fouling material layer 46 is formed in the anti-fouling material layer forming step S3 so as to cover the edge 45a of the previously formed hard material layer 45 in the vicinity of the boundaries B1 and B2. Then, the portion 46a is removed, so that it is possible to reliably prevent a gap from being generated between the hard material layer 45 and the anti-fouling material layer 46 at the boundaries B1 and B2.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

  That is, in the steam turbine blade of each of the above embodiments, the first film covering the first range A1 and the second film covering the second range A2 are either one of the hard material layer and the anti-fouling material layer. However, the present invention is not limited to this. For example, a first intermediate layer may be provided between the base material and the hard material layer. Specifically, a layer made of Cr or Ti is preferably selected as the first intermediate layer. Further, the thickness of the first intermediate layer is preferably selected from about 0.5 to 2 μm. By providing such a first intermediate layer, the internal stress generated in the hard material layer can be relaxed, and the adhesion between the base material and the hard material layer can be enhanced.

  Moreover, when forming a fouling-resistant material layer on a hard material layer, it is good also as what provides a 2nd intermediate | middle layer between each other. Specifically, a layer made of diamond-like carbon (DLC) is preferably selected as the second intermediate layer. Further, the thickness of the second intermediate layer is preferably selected from about 0.5 to 2 μm. By providing such a second intermediate layer, the adhesion between the hard material layer and the anti-fouling material layer can be enhanced.

  Moreover, in the said embodiment, although the steam turbine was mentioned as an example and it demonstrated as a thing provided with a steam turbine blade as a blade, it does not restrict to this. The blade of the present invention can be applied to blades of various rotating machines that are exposed to fluid in the form of wings and can undergo erosion and fouling.

1 Steam turbine (rotary machine)
10, 30, 40 Steam turbine blade (blade)
13 Base material 20, 31, 45 Hard material layer 21, 32, 46 Anti-fouling material layer 25 Shaft body A1 First range A2 Second range B1, B2 Boundary P Abrasive material

Claims (13)

A wing-shaped substrate;
A hard material layer made of a hard material, provided in the uppermost layer in a first range to be a part on the surface of the substrate;
A blade provided with an anti-fouling material layer made of an anti-fouling material provided in the uppermost layer in a second range other than the first range on the surface of the substrate. The blade according to claim 1, wherein
The hard material layer is formed on the surface of the base material in each of the first range and the second range,
The blade, wherein the anti-fouling material layer is formed in an upper layer than the hard material layer in the second range. The blade according to claim 2, wherein
The blade is characterized in that the anti-fouling material layer is formed in the vicinity of the boundary between the first range and the second range so that the thickness gradually decreases toward the boundary. The blade according to claim 2 or claim 3,
The hard material layer is formed so that the layer thickness in the first range is substantially equal to the sum of the layer thickness in the second range and the layer thickness of the anti-fouling material layer. A blade having a range and a layer thickness in the second range are set. A hard material layer forming step of forming a hard material layer made of a hard material in at least a first range which is a part on the surface of the wing-shaped base;
A fouling-resistant material layer forming step of forming a fouling-resistant material layer made of a fouling-resistant material as the uppermost layer in the second range other than the first range on the surface of the base material. A method for manufacturing a blade. In the manufacturing method of the blade according to claim 5,
The hard material layer forming step forms the hard material layer in the first range and the second range,
In the fouling-resistant material layer forming step, the anti-fouling material layer is formed in an upper layer than the hard material layer. In the manufacturing method of the braid | blade of Claim 5 or Claim 6,
The anti-fouling material layer forming step includes a first step of forming the anti-fouling material layer in both the first range and the second range;
And a second step of removing the anti-fouling material layer formed in the first range. In the manufacturing method of the braid | blade of Claim 7,
Said 2nd step is performed by spraying a granular abrasive material to said anti-fouling material layer, and performing a grinding | polishing process, The manufacturing method of the braid | blade characterized by the above-mentioned. The method of manufacturing a blade according to claim 8,
The direction in which the abrasive material is sprayed onto the base material in the second step is set so as to substantially match the relative direction of the fluid flowing around the blade to be manufactured when used. Blade manufacturing method. In the manufacturing method of the braid according to claim 9,
The second step is performed by attaching the base material to the shaft body in a direction similar to the direction in which the blade to be manufactured is attached to the rotation shaft, and rotating the shaft body. Method. In the method for manufacturing a blade according to any one of claims 7 to 10,
The second step includes a rough polishing process in which a polishing process is performed with a large particle diameter of the abrasive, and a polishing process in which the particle diameter of the abrasive is smaller than that during the rough polishing process after the rough polishing process. And a finish polishing process for performing a blade. In the manufacturing method of the braid | blade of Claim 6,
After the hard material layer forming step, the hard material layer is removed in the second range by the thickness of the anti-fouling material layer planned in the anti-fouling material layer forming step. A blade manufacturing method comprising a material layer removing step.   A rotating machine comprising the blade according to any one of claims 1 to 4.

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