Rotating component of gas turbine engine and manufacturing method thereof

Abstract

A rotation unit constituent member (1), which is a constituent member of a gas turbine (GT) engine, is provided with: a rotation unit constituent member body (15) that is made of metal; and a hard particle layer (17) that includes a large number of hard particles (16) made of a material which is harder than the material of the rotation unit constituent member body (15) and includes a base material (20). The base material (20) is made only of the material of which the rotation unit constituent member body (15) is made. The hard particle layer (17) is directly supported on the surface of the rotation unit constituent member body (15).

Description

Related Applications

[0001] This application claims priority to Japanese Patent Application No. 2020-193415, filed November 20, 2020, the entire contents of which are incorporated herein by reference. [Technical Field]

[0002] The present invention relates to a member constituting a rotating part used in a gas turbine engine and a method for manufacturing the same. [Background technology]

[0003] The components that make up the rotating parts of gas turbine engines (rotating part components), such as turbine blades, are arranged so that a small gap is formed between them and the shroud, a fixed component located on the outer diameter side of the blades. However, turbine blades are generally made of metal, and may undergo thermal elongation when exposed to high-temperature gas. In order to maintain an appropriate gap between the blades and the shroud even in such cases, the tip of the rotating part component is required to have abrasive properties that allow it to grind the mating component by sliding against the mating component.

[0004] In order to improve the abrasiveness of the tip of a rotating component, it has been proposed to coat the tip with hard particles (see, for example, Patent Document 1). One possible method for coating the tip of a rotating component with hard particles is directed energy deposition (DED), such as laser cladding. Laser cladding allows for precise control of the application position, and therefore has the advantage of being able to be applied with high precision even to the narrow surfaces of the tip of a rotating component that makes up a gas turbine. Generally, when forming a cladding layer containing hard particles by laser cladding, a laser beam is irradiated onto the target location of the rotating component while spraying both hard particle powder and powder of a metal material that forms a matrix to hold the hard particles. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2004 / 052555 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the method of depositing both hard particle powder and matrix material powder, it is difficult to distribute the hard particles in a concentrated manner only on the matrix surface, resulting in a large number of hard particles that do not contribute to abrasive properties being distributed inside the matrix. Furthermore, the above method requires equipment for supplying multiple types of powder, and complex control of the supply ratio, timing, etc. Therefore, it is difficult to sufficiently improve the abrasive properties of the tip of the rotating part component, and waste occurs in terms of cost.

[0007] SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to improve the abrasiveness of rotating components used in gas turbine engines by a simple method at low cost. [Means for solving the problem]

[0008] In order to achieve the above object, a rotating part component according to the present invention is a component that constitutes a rotating part of a gas turbine engine, a metallic rotating part component body; a hard particle layer comprising a plurality of hard particles formed from a material harder than the material forming the rotating portion component body and a base material formed only from the material forming the rotating portion component body, the hard particle layer being directly supported on the surface of the rotating portion component body; It is equipped with:

[0009] With this configuration, the hard particles are supported in an exposed state on the surface of the rotating component, thereby reliably improving abrasiveness. Furthermore, since only hard particles are used as the build-up material on the surface of the rotating component, application is simplified and unnecessary hard particles that do not contribute to improving abrasiveness are significantly reduced, improving cost efficiency.

[0010] Further, a method for manufacturing a rotating portion component according to the present invention includes the steps of: forming a metallic rotating portion component; Irradiating a surface of the rotating portion component body with a directed energy beam, and spraying only a powder of hard particles made of a material harder than the material forming the rotating portion component body onto the portion irradiated with the directed energy beam, thereby forming a hard particle layer made of a large number of the hard particles and a base material that holds the hard particles and is made only of the material forming the rotating portion component body; Includes.

[0011] According to this configuration, by using so-called directed energy deposition, it is possible to perform the process with high precision even when forming a hard particle layer on a narrow surface such as the tip of a turbine blade as a rotating part component.

[0012] Any combination of at least two features disclosed in the claims and / or the description and / or the drawings is included in the present invention. In particular, any combination of two or more of the individual claims is included in the present invention. [Brief explanation of the drawings]

[0013] The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are merely for illustration and explanation, and should not be used to define the scope of the present invention, which is defined by the appended claims. In the accompanying drawings, the same reference numerals in multiple drawings indicate the same or corresponding parts. [Figure 1] 1 is a longitudinal cross-sectional view showing an example of a gas turbine engine including a rotating component according to an embodiment of the present invention. [Figure 2] 1 is a plan view showing a turbine rotor blade, which is a rotating part component according to an embodiment of the present invention. FIG. [Figure 3] 3 is a cross-sectional view showing a rotary part component according to one embodiment of the present invention, taken along line III-III in FIG. 2.

[0023] FIG. [Figure 4] FIG. 4 is an enlarged cross-sectional view schematically showing the periphery of the hard particle layer in FIG. 3. [Figure 5] 5 is an enlarged cross-sectional view schematically showing the periphery of an edge of the hard particle layer of FIG. 4. FIG. [Figure 6] 10 is a schematic cross-sectional view for explaining a method for calculating an embedment rate in a hard particle layer of a rotating part component according to an embodiment of the present invention. FIG. [Figure 7] FIG. 10 is a schematic plan view for explaining a method for calculating the burial rate. [Figure 8] 1 is a schematic diagram illustrating an example of a DED device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to this embodiment.

[0015] 1 shows a gas turbine engine (hereinafter simply referred to as a gas turbine) GT equipped with a rotating component 1 according to one embodiment of the present invention. In the gas turbine GT, air introduced from the outside is compressed by a compressor (not shown) and introduced into a combustor 3, where fuel is burned together with the compressed air, and the resulting high-temperature, high-pressure combustion gas is supplied into a turbine 5 to drive the turbine 5.

[0016] In the turbine 5, a plurality of nozzles (stationary vanes) 7 and a plurality of turbine rotor blades 11 arranged on the outer peripheral surface of a rotor 9 that constitutes the rotating part of the gas turbine GT are arranged adjacent to each other alternately in the axial direction. Below, the turbine rotor blades 11 will be mainly described as an example of the rotating part constituent member 1 in this embodiment. The outer side of each turbine rotor blade 11 in the radial direction R is covered by a shroud (part of the turbine 5 casing) 13. In other words, the tip end of the turbine rotor blade 11 in the radial direction R faces the shroud 13 via a small gap.

[0017] In this specification, the rotating part component 1, i.e., the component that constitutes the rotating part of the gas turbine engine, includes not only rotating side components (for example, the turbine rotor blades 11 and rotor 9) but also stationary side components that are radially opposed to the rotating side components (for example, the shroud 13). In addition to the components exemplified above, the rotating part component also includes, for example, a compressor impeller, rotor, or labyrinth seal.

[0018] In this specification, the terms "radial direction R" and "circumferential direction Q" refer to the radial direction and the circumferential direction, respectively, based on the rotation axis C of the rotating portion component 1.

[0019] As shown in FIG. 2, the turbine rotor blade 11 has an overall curved shape that bulges out to one side in the circumferential direction Q. As shown in FIG. 3, the turbine rotor blade 11, which is the rotating part component 1 according to this embodiment, includes a metallic rotating part component body 15 and a hard particle layer 17 made of a large number of hard particles 16 and a base material 20, which will be described later. The hard particle layer 17 is formed on a surface 19 of a tip portion 15a in the radial direction R of the rotating part component body 15 (hereinafter simply referred to as the "tip surface"). More specifically, as shown in FIG. 2, the tip portion 15a of the turbine rotor blade 11 is formed so that a central portion 15aa thereof is slightly recessed inward in the radial direction R, and an edge portion 15ab of the central portion 15aa protrudes slightly outward in the radial direction R by the amount of this recess. The hard particle layer 17 shown in FIG. 3 is formed on a surface 19 of the edge portion 15ab of the tip portion 15a.

[0020] In this specification, "hard particles" refers to particles formed from a material harder than the material that supports them and forms the rotating part component body 15. The hard particles 16 are also harder than the material that forms the member that faces the tip end portion 15a of the rotating part component 1 (in this example, the shroud 13 shown in FIG. 1).

[0021] In this way, by providing the hard particle layer 17 on the surface of the rotating body component 1, the abrasiveness of the rotating body component 1 is improved. To more efficiently improve the abrasiveness of the rotating body component 1, the surface occupancy rate of the hard particles 16 in the hard particle layer 17 is preferably, for example, 55% or more, and more preferably 65% ​​or more. Here, the "surface occupancy rate" refers to the ratio of the area of ​​the hard particles 16 exposed to the outside to the total surface area of ​​the hard particle layer 17.

[0022] In this embodiment, the large number of hard particles 16 contained in the hard particle layer 17 are formed from a single type of material. This configuration simplifies the process. Specifically, since no overlay material other than the rotating part component body 15 and the hard particles 16 made of a single type of material is used, no equipment for supplying multiple types of powder is required during overlay processing, and complex control of the supply ratio, timing, etc. is also unnecessary. However, the hard particle layer 17 may contain multiple types of hard particles made from different materials.

[0023] In this specification, as shown in Fig. 4, a material that is different from the hard particles and that surrounds the hard particles 16 to hold the hard particles 16 is generally referred to as a "base material 20." In this embodiment, only the material that forms the rotating part component body 15 forms the base material 20. In this embodiment, the base material that is the material of the rotating part component body 15 is a nickel (Ni)-based heat-resistant alloy, and the rotating part component body 15 is formed by casting. The material that forms the hard particles is cubic boron nitride (cBN).

[0024] In addition, even if the hard particle layer 17 contains multiple types of hard particles formed from different materials, if a specific type of particle is provided for the purpose of holding other types of particles, the specific type of particle is the "base material" as defined in this specification (however, in this case, it does not fall under the category of "base material formed only from the material that forms the main body of the rotating part component") and does not fall under the category of "hard particles."

[0025] The materials of the rotating part component 1 and the materials forming the hard particles 16 are not limited to the above examples. For example, titanium (Ti)-based alloys, cobalt (Co)-based alloys, iron (Fe)-based alloys, etc. can be used as the material of the rotating part component body 15. Furthermore, the manufacturing method of the rotating part component body 15 is not limited to casting. For example, titanium carbide (TiC), silicon carbide (SiC), tungsten carbide (WC), niobium carbide (NbC), chromium carbide (Cr3C2), etc. can be used as the material of the hard particles 16.

[0026] More specifically, the hard particle layer 17 is directly supported on the tip end surface 19 of the rotating part component body 15. In this specification, being "directly" supported means that the hard particle layer 17 is supported in contact with the tip end surface 19 without using a build-up material other than the material forming the rotating part component body 15 as the base material 20 to hold the hard particles 16.

[0027] In other words, the portion of the rotating part component body 15 adjacent to the hard particle layer 17 (in this example, the tip portion 15a), which is integral with the base material 20 of the hard particle layer 17, is formed from the same material as the main portion 15b (excluding the tip portion 15a) of the rotating part component body 15, and the peripheral portion 15ab (side surface) of the tip portion 15a has a surface condition that is continuous with the main portion 15b and a shape that is continuous with the main portion 15b. In this specification, the term "surface condition that is continuous with the main portion 15b" refers to the absence of discontinuous portions such as seams between the tip portion 15a and the main portion 15b, and the gloss and surface roughness are the same. For example, if the side surface of only the tip portion 15a is ground, this does not fall under the category of "surface condition that is continuous with the main portion 15b." In addition, in this specification, the term "shape that is continuous with the main portion 15b" refers to the smooth connection of the linear or curved surface from the main portion 15b to the tip portion 15a in a cross-sectional view. For example, if only the tip portion 15a has a shape that bulges out to the side, this does not fall under the category of "a shape that is continuous with the main body portion 15b."

[0028] In this embodiment, the hard particle layer 17 is formed in the region of the tip end portion 15a of the rotating portion component body 15 in plan view (viewed in the radial direction R).

[0029] As described above, in the rotating part component 1 of this embodiment, no overlay material other than the rotating part component body 15 and the hard particles 16 is used, so it is possible to eliminate lateral bulging of the overlay portion from the rotating part component body 15. It is also possible to suppress bulging of the overlay portion toward the tip side. This allows the rotating part component 1 to be used with a shape and dimensions close to the design specifications, making it easier to ensure the performance of the gas turbine GT to which it is applied.

[0030] From an aerodynamic viewpoint, the edge angle α of the hard particle layer 17 (the angle between the side surface and the tip surface at the most distal end of the hard particle layer) shown in Fig. 5 is preferably equal to or greater than 90° and close to 90°. Specifically, the edge angle α is preferably, for example, equal to or less than 150°, and more preferably equal to or less than 135°.

[0031] In the rotating part component 1 according to this embodiment, the embedment ratio of the hard particles 16 is less than 100% and is 70% or more. In this specification, the "embedding ratio" of the hard particles 16 refers to the ratio of the length of the portion of the hard particle 16 embedded in the base material 20 in the cross section of the hard particle layer 17. That is, in the cross section of the hard particle layer 17 shown in FIG. 6, if the length of the portion of the hard particle 16 protruding from the base material surface 20a in the direction perpendicular to the base material surface 20a (hereinafter referred to as the "protruding portion length") is Lp and the length of the portion of the hard particle embedded in the base material 20 in the direction perpendicular to the base material surface (hereinafter referred to as the "embedded portion length") is Lb, the embedment ratio of each hard particle 16 (hereinafter referred to as the "individual embedment ratio") is calculated as Lb / (Lp+Lb). In this embodiment, the average value of the individual embedment rates of the hard particles 16 contained in the test pieces extracted from the rotating part component 1 as described below is taken as the "embedding rate," and this value is set to be less than 100% and greater than or equal to 70%.

[0032] As shown in Figure 7, the cross section S of the rotating part component 1 for measuring the embedment ratio is a cross section cut perpendicular to the base material surface 20a along the application direction X of the hard particle layer 17, i.e., the direction in which the powder spray nozzle is moved during application (described later), and at the center of the width direction (direction perpendicular to the application direction X) of the base material surface 20a. The application direction X is typically the longitudinal direction in a plan view of the rotating part component 1. The embedment ratio is the average value of the individual embedment ratios of all the hard particles 16 present in this cross section. However, particles with extremely small particle sizes observed in the cross section S are likely to be the ends of particles, and are therefore excluded from the calculation of the average value to improve the accuracy of the embedment ratio.

[0033] By setting the embedment rate to 70% or more, the hard particles 16 are more reliably held by the base material 20, and the hard particles 16 can be prevented from falling off when the rotating part component 1 comes into sliding contact with a mating member. In particular, by setting the embedment rate to 70% and the surface coverage rate to 55% or more as described above, it becomes possible to maintain high abrasiveness for a long period of time. The embedment rate is more preferably in the range of 80% to 95%, and even more preferably in the range of 85% to 90%. However, the embedment rate may be less than 70%.

[0034] In this embodiment, the hard particle layer 17 is formed on the tip surface 19 of the rotating part component body 15 by directed energy deposition (hereinafter referred to as "DED"). Specifically, in this embodiment, the hard particle layer 17 is formed by laser cladding, which uses laser light as the directed energy. 8 As shown in FIG. 1, a laser beam 25 is irradiated from a nozzle 23 of a DED device 21 toward the tip 15a of a rotating part component body 15, which is the base material, and a powder 27 of hard particles is sprayed onto the portion irradiated with the laser beam 25.

[0035] The DED device 21 used in this embodiment includes a directed energy beam (laser light in this example) irradiator (not shown) located in the center, and a powder injection nozzle (nozzle 23) having an annular slit concentrically arranged around the directed energy beam irradiator. The powder injection nozzle may also be a nozzle having a plurality of holes concentrically arranged at equal intervals around the directed energy beam irradiator. By using such a device, construction to provide a hard particle layer can be performed with a simple configuration. However, the specific construction mode using DED is not limited to the example shown in the figure, and other commonly used construction modes may also be used.

[0036] By using DED, it becomes possible to perform build-up welding with high precision in a narrow width range (for example, about 0.3 mm to 3 mm) such as the tip end surface 19 of the turbine rotor blade 11. This makes it possible to form the hard particle layer 17 itself in the region of the tip end 15a of the rotating part component body 15 in a plan view (viewed in the radial direction R), as described above.

[0037] The method for forming the hard particle layer 17 is preferably the above-mentioned DED, since it allows for build-up application locally on the tip end surface 19 of the turbine rotor blade 11 with high precision. However, any method other than DED may be used as long as it allows for formation with precision equal to or higher than that of DED.

[0038] In order to facilitate the above-mentioned high-precision application, the particle size of the hard particles 16 is preferably smaller than the width of the area to be applied.

[0039] The tip portion 15a of the rotating part component body 15 on which the hard particle layer 17 is formed may have a layer that has been subjected to a surface treatment such as oxidation resistance treatment. In this case, the hard particle layer 17 may be formed by DED after the tip portion 15a of the rotating part component body 15 has been subjected to the surface treatment, or the surface treatment may be performed after the hardened particle layer 17 has been formed.

[0040] The hard particle layer 17 may also be formed after the damaged portion of the rotating portion component body 15 has been repaired.

[0041] As described above, according to the rotating part component 1 and the manufacturing method thereof of this embodiment, the hard particles are supported in an exposed state on the surface of the tip portion 15a of the rotating part component 1, thereby reliably improving the abrasiveness.

[0042] Furthermore, the amount of unnecessary hard particles that do not contribute to improving abrasiveness can be significantly reduced, thereby improving cost efficiency.

[0043] Although the preferred embodiments of the present invention have been described above with reference to the drawings, various additions, modifications, and omissions can be made without departing from the spirit of the present invention. Therefore, such additions, modifications, and omissions are also included in the scope of the present invention. [Explanation of symbols]

[0044] 1 Rotating section components 11 Turbine blades 15 Rotating section component body 16 hard particles 17 Hard particle layer 20 Base material 21 DED device 25 Laser light (directed energy beam) GT Gas Turbine Engine

Claims

1. A rotating part component that configures a rotating part of a gas turbine engine, a metallic rotating part component body; a hard particle layer comprising a plurality of hard particles formed from a material harder than the material forming the rotating portion component body and a base material formed only from the material forming the rotating portion component body, the hard particle layer being directly supported on the surface of the rotating portion component body; Equipped with A rotating part component, wherein an embedment ratio, which is a ratio of a length of a portion of the hard particle embedded in the base material in a cross section of the hard particle layer, is less than 100% and not less than 70%.

2. 2. The rotating part component according to claim 1, wherein the hard particle layer is A rotating part component formed by irradiating a surface of the rotating part component body with a directed energy beam and spraying a powder of the hard particles onto the portion irradiated with the directed energy beam.

3. 3. The rotating part component according to claim 1, wherein the hard particle layer contains only the hard particles formed from a single type of material.

4. 4. The rotating part component according to claim 1, wherein a portion of the rotating part component body adjacent to the hard particle layer and other portions have a continuous surface condition and a continuous shape.

5. 5. The rotating part component according to claim 1, wherein the hard particle layer is formed in a region of a portion of the rotating part component body adjacent to the hard particle layer when viewed in a radial direction.

6. 6. The rotating part component according to claim 1, wherein the rotating part component is a turbine blade.

7. A rotating part component as described in any one of claims 1 to 6, wherein the surface occupancy rate of the hard particles in the hard particle layer is 55% or more.

8. A rotating part component that constitutes a rotating part of a gas turbine engine, a metallic rotating part component body; a hard particle layer comprising a plurality of hard particles formed from a material harder than the material forming the rotating portion component body and a base material formed only from the material forming the rotating portion component body, the hard particle layer being directly supported on the surface of the rotating portion component body; Equipped with A rotating part component, wherein the surface occupancy of the hard particles in the hard particle layer is 55% or more.

Images