JP3564376B2 - Polishing layer, combustion engine, gas turbine, and method of manufacturing the same - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is used in a so-called abrasive coating or the like that prevents the destruction and burning of the opposite member by shaving the other side at the time of sliding at a place where two opposing members may slide. Polishing layer to be used.
For example, the present invention relates to a combustion layer such as a gas turbine and a jet engine, and particularly to a polishing layer applied to a combustion engine which may slide due to a need to fill a gap between a rotor blade and a shroud and the combustion engine and the combustion layer. is there.
[0002]
[Prior art]
A clearance of a predetermined size is provided between the tip of the blade of the gas turbine and the shroud facing the tip of the blade so that they do not come into contact during operation.
If the clearance is too large, combustion gas leaks from the pressure surface side of the rotor blade to the negative pressure surface side, resulting in a large pressure loss and a reduction in operating efficiency.
In order to prevent this and improve the performance of the gas turbine, attempts have been made to set the clearance as small as possible.
[0003]
However, if the clearance is too small, the tip of the moving blade and the shroud may be disturbed in the initial stage of gas turbine operation due to the difference in thermal expansion between the moving blade and the shroud, the eccentricity of the turbine rotor, and vibrations occurring in the entire gas turbine. May slide, and this is called initial sliding.
Further, as the gas turbine is operated, the shroud exposed to the high-temperature gas gradually undergoes thermal deformation, and the tip of the moving blade may also slide on the shroud. Call it movement.
During initial sliding, intense sliding between the tip of the blade and the shroud may occur, whereas secondary sliding is generally relatively gentle sliding.
[0004]
Generally, the shroud has a heat-shielding coating (such as zirconia (ZrO2)) on its inner peripheral surface. T hermal B arrier C oating, hereinafter referred to as TBC. ) Or an oxidation-resistant coating made of MCrAlY. In the case of a coating made of zirconia, the hardness is usually higher than that of the base metal of the rotor blade.
For this reason, if the tip of the moving blade slides on the inner peripheral surface of the shroud, the moving blade may be greatly damaged.
[0005]
As a countermeasure against such sliding, Japanese Patent Application Laid-Open No. 4-218984 discloses a gas turbine blade provided with a polishing layer in which abrasive particles are dispersed in a matrix made of MCrAlY which is an antioxidant material. .
In this rotor blade, as abrasive particles, for example, cubic boron nitride ( C ubic B oron N itrido, hereafter called CBN. ) Etc. are used.
CBN has a higher hardness than zirconia.
Therefore, when the blade tip slides on the inner peripheral surface of the shroud, the abrasive particles made of the CBN polish the inner peripheral surface of the shroud.
Thereby, an appropriate clearance is maintained between the bucket and the shroud. The manufacturing method and the like are also described in JP-A-9-504340, JP-A-10-30403, and US Pat. No. 5,702,574.
[0006]
[Problems to be solved by the invention]
However, since CBN does not have sufficient heat resistance, abrasive particles may be oxidized, melted or sublimated and disappear by long-term operation in an oxidizing atmosphere.
Also, with the deterioration of MCrAlY due to oxidation, CBN particles may gradually fall off.
Therefore, although the shroud is polished by the abrasive particles during the initial sliding, the polishing is insufficient in the secondary sliding after the polishing layer is degraded, and the blade may be greatly damaged.
In particular, in recent years, the combustion temperature in the gas turbine has tended to increase from the viewpoint of improving energy efficiency, and the problem of thermal deterioration of the polishing layer has become more prominent.
Similar problems are found in combustion engines other than gas turbines, such as jet engines, for example.
[0007]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a polishing layer capable of exhibiting polishing performance over a long period of use.
Further, by applying this polishing layer, an appropriate clearance between the blade and the shroud is maintained, and therefore, there is provided an engine in which damage to the blade is less likely to occur.
Still another object of the present invention is to provide a method for forming a polishing layer suitable for such a combustion engine.
[0008]
[Means for Solving the Problems]
The invention made to achieve the above object is as follows.
[0009]
First, as an invention of a polishing layer, a first layer having a coating material in which first abrasive particles are dispersed and a first layer having a coating material in which second abrasive particles are dispersed are located on the outer surface side of the first layer. It is a polishing layer characterized by having two layers.
[0010]
Further, as an apparatus invention, a first layer having a coating material in which first abrasive particles are dispersed is provided on one of surfaces of a combustion engine including a compressor, a combustor, and a turbine in which a movable portion and a non-movable portion face each other. And a second layer located on the outer surface side of the first layer having a coating material in which second abrasive particles are dispersed.
[0011]
Further, as an invention of the manufacturing method, a step of fixing the first abrasive particles by metal plating on the surface on which the film is to be formed, a step of forming a coating material on the metal plating to which the first abrasive particles are fixed, A step of fixing second abrasive particles to the coating material by metal plating, and a step of forming a coating material on the metal plating to which the second abrasive particles are fixed. It is a manufacturing method.
[0012]
According to these inventions, for example, even if the second layer on the outer surface side deteriorates or disappears in the initial sliding, the first coating layer remains, and the inner peripheral surface of the shroud is formed by the first abrasive particles of the first layer. The surface is polished.
Therefore, good polishing performance can be exhibited over a long period of use.
In addition, by applying the main polishing layer to either the blade or the shroud surface of the combustion engine, even when the blade and the shroud are assembled close to each other, an appropriate clearance between the blade and the shroud is maintained. As a result, the performance of the combustion engine can be improved, and damage to the rotor blades and the shroud can be prevented.
When the polishing layer is provided on the tip of the blade, the inner peripheral surface of the shroud is polished. When the polishing layer is provided on the inner periphery of the shroud, the tip of the blade is polished by abrasive particles. As a result, the clearance between the bucket and the shroud is maintained.
Further, in the production of the polishing layer, since the heat-resistant abrasive particles are fixed by metal plating, the fixing and dispersion of the abrasive particles in each layer can be efficiently and easily performed.
[0013]
As a polishing layer invention, preferably, the abrasive particles of the first and second layers have higher hardness than the inner peripheral surface of the shroud. Thereby, polishing of the shroud is more reliably achieved.
The hardness used in the present specification is a hardness in a general sense such as Vickers hardness (HV) measured at normal temperature.
[0014]
In the polishing layer, preferably, the first abrasive particles of the first layer are particles whose heat-resistant temperature is higher than the heat-resistant temperature of the second abrasive particles of the second layer, and the second abrasive particles of the second layer are And particles whose hardness is higher than the first abrasive particles of the first layer.
Thus, in the initial sliding in which the blade and the shroud slide violently, the shroud is polished in a relatively short time by the second abrasive particles of the second layer having high hardness.
On the other hand, even after the second layer has disappeared due to long-term operation, the first abrasive particles of the first layer having excellent heat resistance remain, thereby continuing polishing during secondary sliding.
[0015]
Further, preferably, each layer contains an antioxidant as a main component, so that the abrasive particles can be prevented from being oxidized, and in addition, the base material at the blade tip portion that is the film-forming surface can be prevented from being oxidized. .
Further, since heat-resistant particles such as alumina particles, silicon carbide particles, and sintered diamond particles are preferably dispersed in the first layer, the first layer having excellent heat resistance and relatively hardness is preferably used. Layers can be formed.
In addition, since the CBN particles are preferably dispersed in the second layer, the second layer having high hardness and excellent polishing performance can be formed.
Preferably, the thickness of the first layer is equal to or greater than the particle diameter of the abrasive particles, so that the tip of the abrasive particles does not protrude from the first layer. Abrasion particles do not hinder plating.
In addition, since the thickness of the second layer is preferably set to be equal to or less than the particle diameter of the abrasive particles, the shroud is polished from an extremely early stage at which the blade tip and the shroud start sliding, and Wing damage is more reliably prevented.
[0016]
Further, the inner peripheral surface of the shroud is made of zirconia (ZrO). ₂ ) As the main component, the material of the abrasive particles of the first layer is alumina (Al ₂ O ₃ ), Silicon carbide (SiC), and one or more selected from the group consisting of sintered diamonds, and CBN is suitable as the material of the abrasive particles of the second layer.
[0017]
Preferably, the porosity of the matrix of the first coating layer and the second coating layer is 1% or less.
Thereby, the deterioration of the matrix due to oxidation is more reliably prevented, and the falling off of the abrasive particles is suppressed.
The preferred main component of the matrix is MCrAlY.
M in MCrAlY means one or more metal elements selected from the group consisting of iron, nickel and cobalt.
That is, MCrAlY is an alloy containing iron, nickel, or cobalt, chromium (Cr), aluminum (Al), and yttrium (Y) as main components.
[0018]
As a device invention, preferably, since a polishing layer is provided at the tip of a moving blade attached to a rotor of a gas turbine, a high-temperature combustion gas of a gas turbine whose combustion gas temperature has recently been raised to improve efficiency has been improved. Even in the case of the moving blade exposed to the water, good polishing performance can be exhibited in any of the initial sliding and the secondary sliding, so that the clearance can be maintained and the blade can be prevented from being damaged.
[0019]
As the invention of the manufacturing method, preferably, a protruding portion is provided at a tip of a rotor blade attached on a circumference to a rotor of a gas turbine in a circumferentially outward direction, and a polishing layer is formed on the protruding portion. When the coating surface is easy to identify, such as masking of the non-deposition surface during plating or thermal spraying, and in the unlikely event that the blade tip and the shroud come into rapid contact and exceed the polishing capability of the polishing layer However, since the protruding portion is destroyed first, it is possible to prevent the rotor blade main body from being damaged and a large trouble from occurring in the entire gas turbine.
[0020]
As a manufacturing method invention, preferably, the first plating step and the second plating step are formed by nickel electroplating.
The nickel plating layer has high heat resistance, and also has good compatibility with the first coating layer and the second matrix.
[0021]
Preferably, the first film forming step and the second film forming step are achieved by thermal spraying of an antioxidant material. Since thermal spraying has a high film forming rate, it is more efficient than, for example, a case where a polishing layer is formed only by electroplating.
[0022]
Preferably, in the first film forming step, thermal spraying is performed until the first abrasive particles are buried by the antioxidant material.
Thereby, the tip of the first abrasive particles does not protrude from the first coating layer, and therefore, the first abrasive particles do not hinder the electroplating performed on the first coating layer. .
[0023]
Preferably, the thermal spraying in the second film forming step is performed until the second abrasive particles are buried in the second matrix.
Then, the second matrix is polished by the abrasive having a hardness lower than the hardness of the second abrasive particles and higher than the hardness of the second matrix until the second abrasive particles protrude from the second matrix. You.
Since the hardness of the abrasive is lower than the hardness of the second abrasive particles, the second matrix is polished without the second abrasive particles being polished.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a schematic diagram showing the entire gas turbine.
In the gas turbine 1, air is sucked in from the left side of the compressor 2, compressed by the compressor 2, and the compressed compressed air is supplied to the combustor 4 and mixed with fuel to be continuously burned.
Then, the high-temperature and high-pressure combustion gas obtained by the combustion in the combustor 4 is sent to the turbine 6 and drives the rotor blades implanted in the rotor 8 of the turbine.
In the gas turbine 1, the higher the temperature of the combustion gas supplied to the turbine 6 is, the higher the efficiency is.
For example, the turbine inlet temperature has been increased from the conventional 1000 ° C. to 1300 ° C., and further to 1500 ° C.
[0025]
FIG. 2 is a partial sectional view in the axial direction of the turbine 6 of the gas turbine 1.
Combustion gas is supplied from the left side toward the drawing, and the stationary blades and the moving blades are arranged alternately in the order of the first stage stationary blade 101, the first stage moving blade 201, the second stage stationary blade 102, the second stage rotating blade 202, and the third stage stationary blade 103. ing.
Then, in each stage, the combustion gas rectified by the stationary blade drives the rotor blade on the downstream side.
At this time, the gap between the moving blade and the outer periphery of the moving blade is reduced as much as possible, and the combustion gas does not sufficiently provide the driving force to the moving blade. It is designed not to reduce the efficiency of the system.
[0026]
FIG. 3 is an enlarged view of a rotor blade portion of the turbine portion of FIG. 2 and is a partial cross-sectional view illustrating a part of the gas turbine 1 (or a combustion engine) according to an embodiment of the present invention.
The gas turbine 1 includes a moving blade 3 and a shroud 5, and the moving blade 3 includes a polishing layer 7 at a tip thereof.
The shroud 5 located on the outer peripheral side of the tip of the rotor blade 3 has a TBC layer 9 mainly composed of zirconia on the inner peripheral surface.
The clearance between the polishing layer 7 and the TBC layer 9 (indicated by a double-headed arrow C in FIG. 3) is a clearance.
[0027]
FIG. 4 is an enlarged sectional view showing a part of the tip of the bucket 3 of FIG.
Although not shown, the shroud 5 is located above the FIG. 4 with a clearance therebetween. FIG. 4 shows the base material 11 of the rotor blade and the polishing layer 7.
The polishing layer 7 includes a first layer 13 and a second layer 15.
The first layer 13 includes a first plating layer 17, a first coating layer 19, and first abrasive particles 21.
The second layer 15 includes a second plating layer 23, a second coating layer 25, and second abrasive particles 27.
In FIG. 4, the boundary between the first plating layer 17 and the first coating layer 19 is clearly drawn, but the boundary is actually ambiguous due to diffusion.
Similarly, the boundary between the second plating layer 23 and the second coating layer 25 is ambiguous due to diffusion.
[0028]
The first plating layer 17 is provided on the surface of the base material 11 of the rotor blade 3.
As will be described later in detail, the first abrasive particles 21 are temporarily fixed by the first plating layer 17 until the first coating layer 19 is formed.
The material of the first plating layer 17 is not particularly limited. For example, nickel, chromium, or the like is used, and nickel, which is one of the component compositions of the first coating layer 19 and is familiar, is preferable.
The thickness of the first plating layer 17 (thickness before the first coating layer 19 is formed) is not particularly limited, but is preferably 30 μm or more and 100 μm from the viewpoint of effectively fixing only the lower end portion of the first abrasive particles 21. The following is preferred.
In addition, since the first plating layer covers the surface of the base material which is the surface on which the film is to be formed, oxidation of the surface of the base material can be prevented.
[0029]
The first coating layer 19 functions as a binder for fixing the first abrasive particles 21.
For the first coating layer 19, an antioxidant material is used.
This suppresses the first abrasive particles 21 from falling off due to oxidation and deterioration of the first coating layer 19.
Preferred antioxidant materials include MCrAlY (an alloy containing iron, nickel, or cobalt, chromium, aluminum, and yttrium as main components).
From the viewpoint of preventing oxidation, the porosity of the first coating layer 19 is preferably 1% or less.
The thickness of the first coating layer 19 is preferably 50 μm or more and 200 μm or less.
If the thickness is less than the above range, the first abrasive particles 21 protrude from the first coating layer 19, which may cause inconvenience in forming the second plating layer 23 as described later in detail.
Conversely, if the thickness exceeds the above range, it may take a long time before the first abrasive particles 21 protrude from the first coating layer 19 after the first layer 13 disappears.
[0030]
The first abrasive particles 21 preferably have a higher hardness than the TBC layer 9 (mainly composed of zirconia) of the shroud 5.
Specifically, the Vickers hardness of the first abrasive particles 21 is preferably 1000 or more.
Examples of such a material include alumina, silicon carbide, sintered diamond, and CBN.
The average particle diameter of the first abrasive particles 21 is preferably 50 μm or more and 200 μm or less from the viewpoint that the polishing of the shroud 5 is efficiently performed.
For the same reason, the number of the first abrasive particles 21 in the first layer 13 is preferably 30 / mm ↓ 2 or more and 50 / mm ↓ 2 or less.
[0031]
The second plating layer 23 is provided on the surface of the first coating layer 19.
As will be described later in detail, the second abrasive particles 27 are temporarily fixed by the second plating layer 23 until the second coating layer 25 is formed.
Although the material of the second plating layer 23 is not particularly limited, nickel, chromium, or the like is used similarly to the first plating layer 17, and nickel is particularly preferable.
The thickness of the second plating layer 23 (thickness before the second coating layer 25 is formed) is not particularly limited, but is preferably 30 μm or more and 100 μm from the viewpoint of effectively fixing only the lower end portion of the second abrasive particles 27. The following is preferred.
[0032]
The second coating layer 25 functions as a binder for fixing the second abrasive particles 27.
An antioxidant material is used for the second coating layer 25.
Thus, the second abrasive particles 27 are prevented from falling off due to oxidation and deterioration of the second coating layer 25.
As a preferable antioxidant material, MCrAlY similar to that of the first coating layer 19 is used.
From the viewpoint of preventing oxidation, the porosity of the second coating layer 25 is preferably 1% or less.
The thickness of the second coating layer 25 is preferably 50 μm or more and 200 μm or less.
If the thickness is less than the above range, the fixation of the second abrasive particles 27 may be insufficient.
Conversely, if the thickness exceeds the above range, the second abrasive particles 27 may be buried in the second coating layer 25.
[0033]
The second abrasive particles 27 preferably have a higher hardness than the TBC layer 9 (mainly composed of zirconia) of the shroud 5.
Specifically, the Vickers hardness of the second abrasive particles 27 (Vickers hardness measured at room temperature, the same applies hereinafter) is preferably 1000 or more.
Examples of such a material include alumina, silicon carbide, sintered diamond, CBN, and the like.
The average particle diameter of the second abrasive particles 27 is preferably 50 μm or more and 200 μm or less from the viewpoint that the polishing of the shroud 5 is efficiently performed.
For the same reason, the number of the second abrasive particles 27 in the second layer 15 is preferably from 10 / mm ↓ 2 to 50 / mm ↓ 2.
[0034]
In the transition stage to the rated operation when the combustion engine is started, the rotor blades 3 of the turbine are heated faster than the shroud 5, and the rotor blades 3 are also subjected to centrifugal force due to rotation. 3 causes thermal expansion faster than the casing portion containing the shroud 5.
Therefore, the moving blade 3 that has rapidly thermally expanded contacts the shroud 5 that has not yet sufficiently thermally expanded, and initial sliding occurs.
During the initial sliding, the second abrasive particles 27 of the second layer 15 at the forefront of the bucket 3 slide on the TBC layer on the inner peripheral surface of the shroud 5, and the TBC layer is cut.
When the second layer 15 has disappeared in the secondary sliding after the rotor blade 3 has been operated for a certain time while being exposed to the high-temperature combustion gas, the first abrasive particles 21 slide with the shroud 5. .
[0035]
The first abrasive particles 21 and the second abrasive particles 27 may be made of the same material. However, the first abrasive particles 21 are preferably those that are stable for a long time in an oxidizing atmosphere because they are difficult to disappear even in a high-temperature environment. Preferably, the second abrasive particles 27 have higher hardness because they can withstand severe initial sliding.
Specifically, the usable temperature of the first abrasive particles 21 is preferably 1000 ° C. or more, and the Vickers hardness of the second abrasive particles 27 is preferably 1000 or more, particularly preferably 5000 or more.
[0036]
As a combination of such abrasive particles, it is preferable that the first abrasive particles 21 be made of alumina, silicon carbide or sintered diamond, and the second abrasive particles 27 be made of CBN.
A particularly suitable material for the first abrasive particles 21 is alumina which has a Vickers hardness of about 2,000, which is not so high, but is stable at about 1500 ° C. for a long time.
The usable temperature of CBN suitable for the second abrasive particles 27 is not so high as about 1000 ° C., but the Vickers hardness is extremely high, about 5000 to 7000.
[0037]
In the rotor blade 3, the polishing layer 7 is constituted by the first layer 13 and the second layer 15, and the polishing layer 7 is formed between the base material 11 and the first layer 13 or between the first layer 13 and the second layer 15. Other layers may be provided between them.
Alternatively, the first layer and the second layer may be formed continuously, and the first abrasive particles may be dispersed in a lower layer portion of the continuous layer, and the second abrasive particles may be dispersed in an upper layer portion.
[0038]
Here, an example of a method of forming the polishing layer 7 on the tip of the bucket 3 will be described in detail.
First, a portion of the base material 11 of the rotor blade 3 other than the portion where the polishing layer 7 is formed is masked, and the base material 11 is arranged in the electrolytic solution of the electrolytic cell.
Next, the first plating layer 17 is formed by performing electroplating.
The first abrasive particles 21 submerged under the electrolytic cell are temporarily fixed by electroplating.
At the stage where the first plating layer 17 is formed to such a thickness that only the lower part of the first abrasive particles 21 is buried in the first plating layer 17, the electroplating is terminated (first plating step).
[0039]
Next, the first coating layer 19 is formed by spraying an antioxidant material above the first plating layer 17 (that is, on the outer surface side of the first abrasive particles 21, in other words, around).
As the thermal spraying method, a plasma spraying method, a high-speed flame spraying method, or the like can be adopted. Thermal spraying is performed until the first abrasive particles 21 are completely buried in the first coating layer 19 (first film forming step).
Although the first coating layer 19 may be formed by electroplating or the like instead of thermal spraying, thermal spraying in which the formation speed of the first coating layer 19 is faster is more efficient and more economical than electroplating. ,preferable.
[0040]
Next, the surface of the first coating layer 19 is washed to remove dirt generated by oxidation or the like.
Then, the second plating layer 23 is formed in the same manner as in the first plating step, and the second abrasive particles 27 are temporarily fixed on the second plating layer 23 (second plating step).
Since the first abrasive particles 21 are buried in the first coating layer 19, even if the first abrasive particles 21 are non-conductive, the first abrasive particles 21 form the second plating layer 23. Is not inhibited.
[0041]
Next, the second coating layer 25 is formed by spraying an antioxidant material in the same manner as in the first film forming step (second film forming step).
The second abrasive particles 27 are buried in the second coating layer 25 by thermal spraying.
Thereafter, a material having a hardness between the hardness of the second coating layer 25 (about HV400 in the case of MCrAlY) and the hardness of the second abrasive particles 27 (about HV5000 in the case of CBN) (for example, alumina which is about HV2000) Only the second coating layer 25 is polished with an abrasive composed of, and the tip of the second abrasive particles 27 is projected from the second coating layer 25 (polishing step).
Note that the second matrix 25 may be formed by electroplating or the like instead of thermal spraying.
In electroplating, the formation speed is slower than in thermal spraying, but it is easy to control the thickness of the second matrix 25 to such an extent that the second abrasive particles 27 are not buried.
[0042]
After the first layer 13 and the second layer 15 are thus formed, a heat treatment is performed.
By the heat treatment, diffusion occurs between each plating layer and each coating layer, thereby improving the adhesion between the layers and homogenizing the components between the layers.
The heat treatment is performed not only for the polishing layer, but also as a heat treatment for the rotor blade base material, and can also be used as a heat treatment for the polishing layer.
[0043]
FIG. 5 shows a more preferable example of the gas turbine blade.
In FIG. 5, a shroud (shown in FIG. 5) is provided at the tip of the moving blade 33 so as to face the outer periphery of the moving blade 33 further along the back surface of the blade profile, that is, toward the outer periphery in the circumferential direction. ) Is provided in the direction approaching the right side.
Then, the above-mentioned polishing layer 37 is formed on the protruding portion which is also called a thinning portion.
Since the polishing layer 37 is formed not on the entire surface of the blade tip but on the protruding portion 39, the film formation surface portion protrudes in the film formation process, so that the distinction from other surfaces is made clearer. Masking and the like of a non-film-forming portion that is not formed becomes easy.
Further, since it is sufficient to form the film only on the protrusion 39, the area of the surface on which the film is to be formed can be reduced, the amount of the film to be formed can be reduced, and effects such as a reduction in manufacturing time and cost can be achieved.
Furthermore, since it has a thin protruding portion protruding from the moving blade 33, the thermal expansion of the moving blade becomes excessive at the time of starting the gas turbine or the like, causing unexpected and severe contact with the shroud, and the polishing catches up with the contact. Even if it disappears, the protruding portion 39 breaks, wears, burns out, etc., and is lost before the main body of the bucket 33, so that it is possible to prevent a serious trouble from occurring in the main body of the bucket 33.
[0044]
As described above, the present invention has been described in detail by taking as an example the case where the polishing layer is provided at the tip of the moving blade. However, a similar polishing layer may be formed on the inner peripheral side of the shroud.
In this case, at least the tip of the moving blade is made of a material having low hardness, and the moving blade is polished by sliding.
Further, in a normal gas turbine, a large number (for example, several tens) of blades are implanted on the rotor for each stage, but a polishing layer may be formed on the tips of all the blades. Conversely, only a part (for example, several) of a number of blades may be provided with a polishing layer.
In the above description, a gas turbine is taken as an example. However, the present invention can be applied to all combustion engines, such as a jet engine, in which a rotor blade and a shroud may slide. The present invention can be effectively applied to devices and parts that may slide in an oxidizing atmosphere.
[0045]
【The invention's effect】
As described above, in the engine of the present invention, an appropriate clearance between the bucket and the shroud is maintained for a long period from the start of operation.
Therefore, in this engine, damage to the rotor blade is less likely to occur, and reliability is improved.
[Brief description of the drawings]
FIG. 1 is a schematic view of a gas turbine according to the present invention.
FIG. 2 is an enlarged sectional view of a turbine portion of the gas turbine.
FIG. 3 is a partial cross-sectional view showing a part of the gas turbine according to one embodiment of the present invention.
FIG. 4 is an enlarged cross-sectional view showing a part of the tip of the bucket shown in FIG. 5;
FIG. 5 is an enlarged view of a tip of a moving blade according to another embodiment of the present invention.
[Explanation of symbols]
1 ... Gas turbine
2 ... Compressor
3 ... rotor blade
4 ... combustor
5 Shroud
6 ... turbine
7 ... polishing layer
8 ・ ・ ・ Rotor
9 ... TBC layer
11 ・ ・ ・ Base material
13 First layer
15 ... second layer
17 ... First plating layer
19: First coating layer
21 first abrasive particles
23 ... second plating layer
25 ... second coating layer
27 ... second abrasive particles

Claims (13)

A first layer having a coating material in which first abrasive particles are dispersed;
A second layer located on the outer surface side of the first layer having a coating material in which second abrasive particles are dispersed;
A polishing layer comprising: A first layer having a coating material in which first abrasive particles are dispersed;
A second layer located on the outer surface side of the first layer having a coating material in which second abrasive particles are dispersed,
The heat-resistant temperature of the first abrasive particles is higher than the heat-resistant temperature of the second abrasive particles,
The polishing layer, wherein the hardness of the second abrasive particles is higher than the hardness of the first abrasive particles. A first layer mainly composed of an antioxidant in which first abrasive particles are dispersed,
A second layer located on the outer surface side of the first layer, the second layer mainly comprising an antioxidant in which second abrasive particles are dispersed;
A polishing layer comprising: A first layer having a coating material in which at least one of alumina particles, silicon carbide particles, and sintered diamond particles is dispersed;
A second layer located on the outer surface side of the first layer having a coating material in which second abrasive particles are dispersed;
A polishing layer comprising: A first layer having a coating material in which first abrasive particles are dispersed;
A second layer located on the outer surface side of the first layer having a coating material in which particles of cubic boron nitride are dispersed;
A polishing layer comprising: A first layer in which first abrasive particles are dispersed in a coating material having a metal plating layer portion and an antioxidant layer portion;
A second layer located on the outer surface side of the first layer in which second abrasive particles are dispersed in a coating material having a metal plating layer portion and an antioxidant layer portion;
A polishing layer comprising: A first layer having a coating material having a thickness greater than or equal to the particle size of the first abrasive particles, wherein the first abrasive particles are dispersed;
A second layer located on the outer surface side of the first layer having a coating material in which second abrasive particles are dispersed;
A polishing layer comprising: A first layer having a coating material in which first abrasive particles are dispersed;
A second layer located on the outer surface side of the first layer having a coating material having a thickness equal to or less than the particle diameter of the second abrasive particles, wherein the second abrasive particles are dispersed;
A polishing layer comprising: A first layer mainly composed of MCrAlY in which at least one of alumina particles, silicon carbide particles, and sintered diamond particles is dispersed;
A second layer located on the outer surface side of the first layer, which is mainly composed of MCrAlY in which particles of cubic boron nitride are dispersed,
A polishing layer comprising: On one of surfaces where a movable part and a non-movable part of a combustion engine including a compressor, a combustor and a turbine face
A first layer having a coating material in which first abrasive particles are dispersed;
A second layer located on the outer surface side of the first layer having a coating material in which second abrasive particles are dispersed;
A combustion engine comprising: At the tip of a moving blade attached to a rotor of a gas turbine including a compressor, a combustor, and a turbine,
A first layer mainly composed of MCrAlY in which at least one of alumina particles, silicon carbide particles, and sintered diamond particles is dispersed;
A second layer located on the outer surface side of the first layer, which is mainly composed of MCrAlY in which particles of cubic boron nitride are dispersed,
A gas turbine comprising: Fixing the first abrasive particles on the surface on which the film is to be formed by metal plating;
Forming a coating material on the metal plating to which the first abrasive particles are fixed;
Fixing the second abrasive particles to the coating material by metal plating;
Forming a coating material on the metal plating to which the second abrasive particles are fixed;
A method for producing a polishing layer, comprising: A rotor blade circumferentially attached to a rotor of a gas turbine, comprising a protruding portion at a tip of the rotor blade in a circumferentially outward direction,
A step of fixing at least one of particles of alumina, particles of silicon carbide, and particles of sintered diamond by metal plating on the protruding portion,
Spraying MCrAlY on the metal plating on which the heat-resistant abrasive particles are fixed;
Fixing the particles of cubic boron nitride by metal plating on the surface of the coating formed in the step;
Spraying MCrAlY on the metal plating on which the high hardness abrasive particles are fixed;
A method for manufacturing a gas turbine rotor blade, comprising:

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