JP4410357B2 - Method for coating shroud contact surface and blade with shroud - Google Patents
Method for coating shroud contact surface and blade with shroud Download PDFInfo
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- JP4410357B2 JP4410357B2 JP34129899A JP34129899A JP4410357B2 JP 4410357 B2 JP4410357 B2 JP 4410357B2 JP 34129899 A JP34129899 A JP 34129899A JP 34129899 A JP34129899 A JP 34129899A JP 4410357 B2 JP4410357 B2 JP 4410357B2
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- Prior art keywords
- shroud
- contact surface
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Description
【０００１】
【発明の属する技術分野】
この発明は、シュラウドコンタクト面のコーティング皮膜が剥離しにくいシュラウドコンタクト面のコーティング方法およびシュラウド付き動翼に関する。
【０００２】
【従来の技術】
図１は、シュラウド付き動翼を示す一部斜視図である。この動翼１の先端には、流体の漏れを防止すると共に動翼１のねじれを拘束するＺ型シュラウド２が形成されており、さらに、隣接する動翼１のシュラウド２との間にコンタクト面３を有している。また、動翼１には、偏流や静翼ノズルパッシング、フラッタなどに起因した各種の振動が発生するため、前記シュラウド２のコンタクト面３には、耐磨耗処理が施されるのが通常である。従来では、ＡＰＳ溶射（大気圧プラズマ溶射）によりトリバロイ（Ｔ−８００：コバルト基耐磨耗材）コーティングを施していた。
【０００３】
【発明が解決しようとする課題】
しかしながら、上記ＡＰＳ溶射では、シュラウド２のコンタクト面３における母材との密着性が低く、剥離しやすいという問題点があった。これは、溶射を行うにあたっては、グリッドブラスト処理などによる前処理を施すことで溶射表面を粗面状態にし、さらに洗浄処理を施すなどして皮膜との密着性を確保するようにするが、これでは不十分で、皮膜の気孔や粒子界面の酸化物が作用して母材との密着性を悪くしているものと考えられる。
【０００４】
この発明は、上記に鑑みてなされたものであって、シュラウドコンタクト面のコーティング皮膜が剥離しにくいシュラウドコンタクト面のコーティング方法およびシュラウド付き動翼を提供することを目的とする。
【０００５】
【課題を解決するための手段】
上述の目的を達成するために、本発明にかかるシュラウドコンタクト面のコーティング方法は、タービン動翼の先端に設けたシュラウドのコンタクト面に、高速フレーム溶射により耐磨耗性を高める皮膜を形成するものである。高速フレーム溶射によってコバルト基耐磨耗材を高速で溶射することにより、溶融した金属粒子がコンタクト面に衝突し、緻密な皮膜を形成する。また、溶射温度がＡＰＳ溶射に比べて低いことにより、溶射中における粒子の酸化が阻害される。これにより、気泡が少なく粒界の酸化物が少ない皮膜が形成され、拡散熱処理をすることによりコンタクト面の母材に対する密着性が向上する。
【０００６】
また、本発明にかかるシュラウドコンタクト面のコーティング方法は、タービン動翼の先端に設けたシュラウドのコンタクト面に、減圧プラズマ溶射あるいは雰囲気プラズマ溶射により耐磨耗性を高める皮膜を形成するものである。減圧下あるいは不活性ガス雰囲気下で溶射を行うことにより、粒子の酸化を防止できると共に皮膜を緻密化することができる。このため、コンタクト面の母材に対する皮膜の密着性が向上する。
【０００７】
また、本発明にかかるシュラウドコンタクト面のコーティング方法は、上記シュラウドコンタクト面のコーティング方法において、さらに、前記皮膜を形成した後、熱拡散処理を施したものである。皮膜の不均一性、密着性などを改善するため、熱拡散処理を施す。この熱拡散処理は、動翼の熱処理と一括して行うようにしても良い。熱拡散処理により、コンタクト面の母材との密着性がさらに向上する。
【０００８】
また、本発明にかかるシュラウド付き動翼は、タービン動翼の先端にシュラウドが設けられ、隣接する動翼のシュラウドとの間にコンタクト面を有するシュラウド付き動翼において、耐磨耗材を高速フレーム溶射することで前記コンタクト面に密着性を高める皮膜を形成したものである。
【０００９】
また、本発明にかかるシュラウド付き動翼は、タービン動翼の先端にシュラウドが設けられ、隣接する動翼のシュラウドとの間にコンタクト面を有するシュラウド付き動翼において、耐磨耗材を減圧プラズマ溶射あるいは雰囲気プラズマ溶射することで前記コンタクト面に耐磨耗性を高める皮膜を形成したものである。
【００１０】
上記高速フレーム溶射、減圧プラズマ溶射あるいは雰囲気プラズマ溶射により形成した皮膜は、緻密で粒界に存在する酸化物が少ないため、コーティング面の母材との密着性がよく、剥離し難い。
【００１１】
【発明の実施の形態】
以下、この発明にかかるシュラウドコンタクト面のコーティング方法およびシュラウド付き動翼につき図面を参照しつつ詳細に説明する。なお、この実施の形態によりこの発明が限定されるものではない。
【００１２】
（実施の形態１）
図１を参照して説明すると、実施の形態１のコーティング方法では、シュラウド２のコンタクト面３に対して、高速ガス炎溶射（ＨＶＯＦ：High Velocity Oxy-Fuel）によりトリバロイコーティングを施す。溶射するトリバロイ（Ｔ−８００）の化学組成を次表に示す。
【００１３】
【表１】
上記トリバロイは粉末状態で溶射ガンに供給され、フレーム温度約２０００℃で一気に加熱溶融されコンタクト面３に対して射出される。ＨＶＯＦのフレーム速度は３００〜５００ｍ／ｓ以上であり、これにより溶射材料がコンタクト面３に衝突し、緻密な皮膜を成膜する。ＨＶＯＦによるコーティング皮膜は、気孔が少ないこと、溶射温度が低いことにより酸化され難いため皮膜の粒界に酸化物が少ないことなどから、拡散熱処理によってコンタクト面３の母材との密着性が優れたものになる。具体的なコーティング皮膜の膜厚は、０．２ｍｍ程度である。また、ＨＶＯＦの他に、ＨＶＡＦ（High Velocity Air Fuel）を用いるようにして、緻密で酸化物の少ない皮膜を得ることができる。このためコンタクト面３の母材との密着性が向上する。
【００１５】
続いて、コンタクト面３にコーティングを施した後は、膜質改善のため真空炉にて拡散熱処理を施す。その熱処理工程の具体例は、つぎの通りである。
この拡散熱処理は、動翼１自体に対する熱処理と一括して行うことができる。なお、以上のように、ＨＶＯＦを用いて溶射を行い、拡散熱処理を施すことにより、コンタクト面３の母材に対して剥離し難いコーティング皮膜を得ることができる。
【００１７】
（実施の形態２）
また、ＨＶＯＦに代えて、減圧プラズマ溶射（ＬＰＰＳ：Low Pressure Plasma Spraying）を用いて成膜するようにしてもよい。プラズマの作動ガスには、アルゴン、アルゴンと窒素の混合ガスなどを用いる。減圧雰囲気中で溶射した皮膜には酸化物の形成がないため、緻密になり、母材との密着性に優れたものとなる。さらに、拡散熱処理により膜質改善することにより、密着性がさらに向上する。なお、減圧プラズマ溶射の他に雰囲気プラズマ溶射を用いることもできる。
【００１８】
なお、上記コーティング皮膜は、高温ガスに曝露され摩擦部分を有するタービン部材にも適用することができる。たとえばシールピンなどのコーティング皮膜形成に有用である。
【００１９】
【発明の効果】
以上説明したとおり、この発明にかかるシュラウドコンタクト面のコーティング方法は、タービン動翼の先端に設けたシュラウドのコンタクト面に、高速フレーム溶射（請求項１）、または減圧プラズマ溶射あるいは雰囲気プラズマ溶射（請求項２）により耐磨耗性を高める皮膜を形成するようにしたので、気孔が少なく粒界の酸化物が少ない皮膜が形成され、コンタクト面の母材との密着性が向上する。さらに、密着性向上のためには、皮膜を形成した後、これに熱拡散処理を施すのが好ましい（請求項３）。
【００２０】
また、この発明にかかるシュラウド付き動翼は、タービン動翼の先端にシュラウドが設けられ、隣接する動翼のシュラウドとの間にコンタクト面を有するシュラウド付き動翼において、耐磨耗材を高速フレーム溶射（請求項４）または減圧プラズマ溶射あるいは雰囲気プラズマ溶射（請求項５）することで前記コンタクト面に密着性を高める皮膜を形成したものである。かかる方法により形成した皮膜は、緻密で粒界に存在する酸化物が少ないため、コンタクト面の母材との密着性がよく、剥離し難い。
【図面の簡単な説明】
【図１】シュラウド付き動翼を示す一部斜視図である。
【符号の説明】
１ 動翼
２ シュラウド
３ コンタクト面[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for coating a shroud contact surface on which a coating film on the shroud contact surface is difficult to peel off, and a rotor blade with a shroud.
[0002]
[Prior art]
FIG. 1 is a partial perspective view showing a moving blade with a shroud. A Z-type shroud 2 is formed at the tip of the moving blade 1 to prevent fluid leakage and restrain the torsion of the moving blade 1. Further, a contact surface is formed between the shroud 2 of the adjacent moving blade 1. 3. Further, since various vibrations due to drift, stationary blade nozzle passing, flutter, etc. occur in the rotor blade 1, the contact surface 3 of the shroud 2 is usually subjected to wear resistance treatment. is there. Conventionally, trivalloy (T-800: cobalt-based wear-resistant material) coating is applied by APS spraying (atmospheric pressure plasma spraying).
[0003]
[Problems to be solved by the invention]
However, the APS spraying has a problem in that the contact with the base material on the contact surface 3 of the shroud 2 is low and is easily peeled off. When spraying, pretreatment such as grid blasting is performed to make the sprayed surface rough and further washed to ensure adhesion to the film. However, it is considered that the pores of the film and oxides at the interface of the particles act to deteriorate the adhesion with the base material.
[0004]
The present invention has been made in view of the above, and an object of the present invention is to provide a shroud contact surface coating method and a shroud-equipped rotor blade in which the coating film on the shroud contact surface is difficult to peel off.
[0005]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, a coating method for a shroud contact surface according to the present invention is a method in which a coating for improving wear resistance is formed on a contact surface of a shroud provided at the tip of a turbine blade by high-speed flame spraying. It is. By spraying the cobalt-based wear-resistant material at high speed by high-speed flame spraying, the molten metal particles collide with the contact surface to form a dense film. Further, since the thermal spraying temperature is lower than that of APS thermal spraying, the oxidation of particles during thermal spraying is inhibited. As a result, a film with fewer bubbles and less oxide at the grain boundary is formed, and the adhesion of the contact surface to the base material is improved by performing diffusion heat treatment.
[0006]
In addition, the coating method of the shroud contact surface according to the present invention is to form a coating for improving the wear resistance on the contact surface of the shroud provided at the tip of the turbine blade by low pressure plasma spraying or atmospheric plasma spraying. By performing thermal spraying under reduced pressure or in an inert gas atmosphere, the oxidation of particles can be prevented and the film can be densified. For this reason, the adhesion of the film to the base material of the contact surface is improved.
[0007]
The shroud contact surface coating method according to the present invention is the above shroud contact surface coating method, in which the film is further formed and then subjected to thermal diffusion treatment. In order to improve the non-uniformity and adhesion of the film, a thermal diffusion treatment is applied. This thermal diffusion treatment may be performed together with the heat treatment of the moving blade. The thermal diffusion treatment further improves the adhesion between the contact surface and the base material.
[0008]
The blade with a shroud according to the present invention has a shroud provided at the tip of the turbine blade and has a contact surface between the shrouds of adjacent blades. As a result, a film for improving the adhesion is formed on the contact surface.
[0009]
The blade with a shroud according to the present invention has a shroud provided at the tip of the turbine blade and has a contact surface between the shrouds of the adjacent blades. Alternatively, a coating for improving the wear resistance is formed on the contact surface by atmospheric plasma spraying.
[0010]
The film formed by the high-speed flame spraying, the low pressure plasma spraying or the atmospheric plasma spraying is dense and has few oxides present at the grain boundaries. Therefore, the coating film has good adhesion to the base material and is difficult to peel off.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a coating method for a shroud contact surface and a moving blade with a shroud according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.
[0012]
(Embodiment 1)
Referring to FIG. 1, in the coating method of the first embodiment, the contact surface 3 of the shroud 2 is subjected to a trivalloy coating by high-speed gas flame spraying (HVOF: High Velocity Oxy-Fuel). The chemical composition of the sprayed trivalloy (T-800) is shown in the following table.
[0013]
[Table 1]
The trivalloy is supplied in a powder state to a spray gun, heated and melted at a frame temperature of about 2000 ° C., and injected onto the contact surface 3. The frame speed of HVOF is 300 to 500 m / s or more, whereby the sprayed material collides with the contact surface 3 to form a dense film. The coating film by HVOF has excellent adhesion to the base material of the contact surface 3 by diffusion heat treatment because there are few pores, and it is difficult to oxidize due to low spraying temperature, so there are few oxides at the grain boundary of the film. Become a thing. The film thickness of the specific coating film is about 0.2 mm. In addition to HVOF, HVAF (High Velocity Air Fuel) can be used to obtain a dense and less oxide film. For this reason, the adhesiveness with the base material of the contact surface 3 improves.
[0015]
Subsequently, after coating the contact surface 3, diffusion heat treatment is performed in a vacuum furnace to improve the film quality. A specific example of the heat treatment process is as follows.
This diffusion heat treatment can be performed together with the heat treatment for the rotor blade 1 itself. As described above, by performing thermal spraying using HVOF and performing diffusion heat treatment, it is possible to obtain a coating film that hardly peels off from the base material of the contact surface 3.
[0017]
(Embodiment 2)
Moreover, it may replace with HVOF and you may make it form into a film using low pressure plasma spraying (LPPS: Low Pressure Plasma Spraying). As the plasma working gas, argon, a mixed gas of argon and nitrogen, or the like is used. A coating sprayed in a reduced-pressure atmosphere has no oxide formation, and thus becomes dense and has excellent adhesion to the base material. Furthermore, the adhesion is further improved by improving the film quality by diffusion heat treatment. In addition to the low pressure plasma spraying, atmospheric plasma spraying can also be used.
[0018]
In addition, the said coating film can be applied also to the turbine member which is exposed to high temperature gas and has a friction part. For example, it is useful for forming a coating film such as a seal pin.
[0019]
【The invention's effect】
As described above, the shroud contact surface coating method according to the present invention is applied to the contact surface of the shroud provided at the tip of the turbine rotor blade by high-speed flame spraying (Claim 1), low pressure plasma spraying or atmospheric plasma spraying (Billing). Since the film for improving the wear resistance is formed by the item 2), a film having few pores and few oxides at the grain boundary is formed, and the adhesion of the contact surface to the base material is improved. Furthermore, in order to improve the adhesion, it is preferable to perform a thermal diffusion treatment on the film after it is formed (Claim 3).
[0020]
The blade with a shroud according to the present invention is a blade with a shroud provided with a shroud at the tip of a turbine blade and having a contact surface between the shrouds of adjacent blades. (Claim 4) or reduced-pressure plasma spraying or atmospheric plasma spraying (Claim 5) forms a film for improving adhesion on the contact surface. The film formed by such a method is dense and has few oxides present at the grain boundaries, and therefore has good adhesion to the base material of the contact surface and is difficult to peel off.
[Brief description of the drawings]
FIG. 1 is a partial perspective view showing a rotor blade with a shroud.
[Explanation of symbols]
1 Rotor 2 Shroud 3 Contact surface
Claims (2)
さらに、前記皮膜を形成した後、前記シュラウドのコンタクト面に拡散熱処理を施したことを特徴とするシュラウドコンタクト面のコーティング方法。On the contact surface of the shroud provided at the tip of the turbine blade, a coating that increases wear resistance is formed by high-speed flame spraying,
Furthermore, after forming the said film | membrane, the diffusion contact heat processing was performed to the contact surface of the said shroud, The coating method of the shroud contact surface characterized by the above-mentioned .
耐磨耗材を高速フレーム溶射することで前記コンタクト面に密着性が高められた皮膜が形成され、
さらに、前記皮膜が形成された後、前記シュラウドのコンタクト面に拡散熱処理が施されることを特徴とするシュラウド付き動翼。In a blade with a shroud provided with a shroud at the tip of a turbine blade and having a contact surface between the shroud of adjacent blades,
Coating adhesion is increased in the contact surface is formed by high-velocity flame spraying wear material,
Furthermore, after said film has been formed, moving blade with a shroud, characterized in Rukoto is diffusion heat treatment is performed on the contact surface of the shroud.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34129899A JP4410357B2 (en) | 1999-11-30 | 1999-11-30 | Method for coating shroud contact surface and blade with shroud |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34129899A JP4410357B2 (en) | 1999-11-30 | 1999-11-30 | Method for coating shroud contact surface and blade with shroud |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2001152803A JP2001152803A (en) | 2001-06-05 |
| JP4410357B2 true JP4410357B2 (en) | 2010-02-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP34129899A Expired - Fee Related JP4410357B2 (en) | 1999-11-30 | 1999-11-30 | Method for coating shroud contact surface and blade with shroud |
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| Country | Link |
|---|---|
| JP (1) | JP4410357B2 (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004052757A (en) * | 2002-05-31 | 2004-02-19 | Toshiba Corp | Turbine moving blade |
| US9284647B2 (en) | 2002-09-24 | 2016-03-15 | Mitsubishi Denki Kabushiki Kaisha | Method for coating sliding surface of high-temperature member, high-temperature member and electrode for electro-discharge surface treatment |
| JP4307444B2 (en) | 2002-09-24 | 2009-08-05 | 株式会社Ｉｈｉ | Method for coating friction surface of high temperature member, high temperature member and electrode for discharge surface treatment |
| CA2483528C (en) | 2002-10-09 | 2015-07-21 | Ishikawajima-Harima Heavy Industries Co., Ltd. | Rotating member and method for coating the same |
| EP1428981A1 (en) * | 2002-12-11 | 2004-06-16 | Siemens Aktiengesellschaft | Turbine blade with a protective coating |
| JP4130894B2 (en) | 2003-01-23 | 2008-08-06 | 本田技研工業株式会社 | Gas turbine engine and manufacturing method thereof |
| JP5529366B2 (en) * | 2007-03-29 | 2014-06-25 | 三菱重工業株式会社 | Coating material, method for producing the same, coating method, and blade with shroud |
| FR2985759B1 (en) * | 2012-01-17 | 2014-03-07 | Snecma | MOBILE AUB OF TURBOMACHINE |
| CN109057873B (en) | 2014-11-06 | 2021-05-18 | 三菱动力株式会社 | Steam turbine rotor blade and steam turbine |
| EP3540095A4 (en) * | 2016-11-09 | 2020-03-25 | IHI Corporation | Sliding member with abrasion-resistant coating film, and method for forming abrasion-resistant coating film |
| JP6985197B2 (en) * | 2018-03-28 | 2021-12-22 | 三菱重工業株式会社 | Rotating machine |
| JP7398198B2 (en) | 2019-03-12 | 2023-12-14 | 三菱重工業株式会社 | Turbine rotor blade and contact surface manufacturing method |
-
1999
- 1999-11-30 JP JP34129899A patent/JP4410357B2/en not_active Expired - Fee Related
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| Publication number | Publication date |
|---|---|
| JP2001152803A (en) | 2001-06-05 |
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