1. Solid particle erosion resistance for turbine bladesThe nanocrystalline multilayer hard film is characterized by comprising a Cr bottom layer, a TiAl transition layer, a TiAlN transition layer and a TiAlCrCN solid particle erosion resistant film layer which are sequentially deposited on the surface of a turbine blade; the TiAlCrCN solid particle erosion resistant film layer is a nanocrystalline (Ti, Al) (C, N) and Cr with a face-centered cubic structure₂N, wherein the nanocrystalline (Ti, Al) (C, N) is the main phase.

2. The solid particle erosion resistant nanocrystalline multilayer hard film for a steam turbine blade according to claim 1, wherein the thickness of the Cr underlayer is 0.3 μm, the thickness of the TiAl transition layer is 0.1 μm, the thickness of the TiAlN transition layer is 2 μm, and the thickness of the TiAlCrCN solid particle erosion resistant thin film layer is 10 μm.

3. A method for preparing a nanocrystalline multilayer hard film for a steam turbine blade resistant to solid particle erosion according to claim 1 or 2, characterized by comprising the steps of: cleaning the surface of the turbine blade, placing the turbine blade on a rotating device in a vacuum chamber for rotating, carrying out plasma cleaning, and then sequentially depositing a Cr bottom layer, a TiAl transition layer, a TiAlN transition layer and a TiAlCrCN solid particle erosion resistant thin film layer on the surface of the turbine blade by adopting a multi-arc ion plating physical vapor deposition method to finish the preparation of the solid particle erosion resistant nanocrystalline multilayer hard film of the turbine blade.

4. The method for preparing a nanocrystalline multilayer hard film resistant to solid particle erosion for a steam turbine blade according to claim 3, wherein in a process of depositing a Cr bottom layer by a multi-arc ion plating physical vapor deposition method, Ar gas with a flow rate of 250sccm and a gas pressure of 1.4Pa is introduced into a vacuum chamber, the deposition temperature is 300 ℃, Cr is used as a deposition target in the deposition process, the arc current is 60A, and the bias voltage is 16V.

5. The method for preparing the nanocrystalline multilayer hard film resistant to solid particle erosion for the steam turbine blade according to claim 3, wherein in the process of depositing the TiAl transition layer by adopting a multi-arc ion plating physical vapor deposition method, Ar gas with the flow rate of 300sccm and the gas pressure of 1.6Pa is introduced into the vacuum chamber, the deposition temperature is 300 ℃, TiAl is used as a deposition target material in the deposition process, the arc current is 60A, and the bias voltage is 18V.

6. The method for preparing solid particle erosion resistant nanocrystalline multilayer hard film for steam turbine blade according to claim 3, wherein in the process of depositing the oxidation resistant TiAlN transition layer by using the multi-arc ion plating physical vapor deposition method, N is introduced into the vacuum chamber₂A mixed gas of gas and Ar gas, wherein N is₂The flow rate of the gas is 380sccm, the flow rate of the Ar gas is 200sccm, the gas pressure of the mixed gas is 1.6Pa, the deposition temperature is 300 ℃, the TiAl alloy is used as a deposition target material in the deposition process, the arc current is 62A, and the bias voltage is 19V.

7. The method for preparing the solid particle erosion resistant nanocrystalline multilayer hard film for the steam turbine blade according to claim 3, wherein N is introduced into the vacuum chamber in the process of depositing the wear-resistant antifriction TiAlCrCN solid particle erosion resistant film layer by adopting a multi-arc ion plating physical vapor deposition method₂Gas, Ar gas and CH₄A mixed gas of gases, wherein, N₂Flow rate of gas, flow rate of Ar gas and CH₄The flow rate of the gas is respectively 500sccm, 150sccm and 150sccm, the gas pressure of the mixed gas is 1.3Pa, the TiAl alloy is used as a deposition target material in the deposition process, the deposition temperature is 300 ℃, the arc current is 66A, and the bias voltage is 20V; cr is used as a deposition target material, the arc current is 60A, and the bias voltage is 16V.

Background

The turbine blades are easily eroded by solid particles, so that it is important to effectively prevent the turbine blades from being eroded by the solid particles. In order to improve the erosion resistance of the turbine blade to solid particles, a hard film (or coating) is one of the effective surface protection methods. Research on foreign hard coatings in the field of solid particle erosion prevention has been widely carried out, and blade solid particle erosion prevention coatings represented by American GE turbines have been successfully applied to long-term high-temperature wear-resistant protection of turbine blades. The German MTU aviation is cooperated with the PVT company technology, the TiN and TiAlN hard coating technology is successfully applied to the aeroengine blade, and the service life of the blade is greatly prolonged.

Therefore, the development of the nano composite structure resistant multilayer hard film material for the surface of the turbine blade and the coating method thereof has great significance for prolonging the service life of the turbine blade.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a solid particle erosion resistant nanocrystalline multilayer hard film for a turbine blade and a preparation method thereof, wherein the preparation method is simple, convenient to operate, low in cost, green and environment-friendly, and does not produce any polluted wastewater or waste gas.

The technical scheme adopted by the invention for solving the problems is as follows: a solid particle erosion resistant nanocrystalline multilayer hard film for a turbine blade is characterized by comprising a Cr bottom layer, a TiAl transition layer, a TiAlN transition layer and a TiAlCrCN solid particle erosion resistant film layer which are sequentially deposited on the surface of the turbine blade; the TiAlCrCN solid particle erosion resistant film layer is a nanocrystalline (Ti, Al) (C, N) and Cr with a face-centered cubic structure₂N, wherein the nanocrystalline (Ti, Al) (C, N) is the main phase.

Furthermore, the TiAl transition layer is composed of Ti element and Al element.

Furthermore, the TiAlN transition layer is composed of Ti element, Al element and N element.

Furthermore, the TiAlCrCN solid particle erosion resistant film layer is composed of Ti element, Al element, Cr element, C element and N element.

Preferably, the thickness of the metal Cr bottom layer is 0.3 μm, the thickness of the TiAl transition layer is 0.1 μm, the thickness of the TiAlN transition layer is 2 μm, and the thickness of the TiAlCrCN solid particle erosion resistant thin film layer is 10 μm.

The preparation method of the solid particle erosion resistant nanocrystalline multilayer hard film for the steam turbine blade comprises the following steps:

cleaning the surface of the turbine blade, placing the turbine blade on a rotating device in a vacuum chamber for rotating, carrying out plasma cleaning, and then sequentially depositing a Cr bottom layer, a TiAl transition layer, a TiAlN transition layer and a TiAlCrCN solid particle erosion resistant thin film layer on the surface of the turbine blade by adopting a multi-arc ion plating physical vapor deposition method to finish the preparation of the solid particle erosion resistant nanocrystalline multilayer hard film of the turbine blade.

Preferably, in the process of depositing the Cr bottom layer by adopting a multi-arc ion plating physical vapor deposition method, Ar gas with the flow rate of 250sccm and the gas pressure of 1.4Pa is introduced into the vacuum chamber, the deposition temperature is 300 ℃, Cr is used as a deposition target material in the deposition process, the arc current is 60A, and the bias voltage is 16V.

Preferably, during the process of depositing the TiAl transition layer by adopting a multi-arc ion plating physical vapor deposition method, Ar gas with the flow rate of 300sccm and the gas pressure of 1.6Pa is introduced into the vacuum chamber, the deposition temperature is 300 ℃, TiAl is taken as a deposition target material during the deposition process, the arc current is 60A, and the bias voltage is 18V.

Preferably, N is introduced into the vacuum chamber in the process of depositing the oxidation-resistant TiAlN transition layer by adopting a multi-arc ion plating physical vapor deposition method₂A mixed gas of gas and Ar gas, wherein N is₂The flow rate of the gas is 380sccm, the flow rate of the Ar gas is 200sccm, the gas pressure of the mixed gas is 1.6Pa, the deposition temperature is 300 ℃, the TiAl alloy is used as a deposition target material in the deposition process, the arc current is 62A, and the bias voltage is 19V.

Preferably, N is introduced into the vacuum chamber in the process of depositing the wear-resistant antifriction TiAlCrCN solid particle erosion resistant film layer by adopting a multi-arc ion plating physical vapor deposition method₂Gas, Ar gas and CH₄A mixed gas of gases, wherein, N₂Flow rate of gas, flow rate of Ar gas and CH₄The flow rate of the gas is respectively 500sccm, 150sccm and 150sccm, the gas pressure of the mixed gas is 1.3Pa, the TiAl alloy is used as a deposition target material in the deposition process, the deposition temperature is 300 ℃, the arc current is 66A, and the bias voltage is 20V; cr is used as a deposition target material, the arc current is 60A, and the bias voltage is 16V.

The invention adopts the industrialized large-scale multi-arc ion plating Physical Vapor Deposition (PVD) multi-component multi-layer and gradient designed film, the components and the performance of each layer are gradually changed, not only the mutual matching of the film and the blade can be enhanced, but also the binding force between the film and the blade can be greatly improved, and the film has good impact toughness; particularly, the Cr metal bottom layer effectively improves the multiple impact toughness of the multilayer film layer. TiAlN is a solid solution strengthening film layer, the TiCrAlCN film layer has good mechanical property and erosion resistance, wherein C element plays a role in refining film grains, Al is a solid solution strengthening element to improve the strength and hardness, Cr which is a strong carbide element can increase carbides in the film, and the hardness and the erosion resistance of solid particles of the film are obviously improved.

The invention adopts Cr/TiAl/TiAlN/TiCrAlCN multi-component multi-layer gradient design to ensure that the mechanical property and the wear-resisting property of the film are also changed in a gradient way, thereby realizing the compatibility of the hardness of the TiAl/TiAlN/TiCrAlCN film layer and the toughness of the Cr layer. Wherein TiAlN is a solid solution reinforced hard film layer with a face-centered cubic structure, and the TiAlCrCN solid particle erosion resistant film layer is nanocrystalline (Ti, Al) (C, N) and Cr with a face-centered cubic structure₂The two-phase composite structure of N, and (Ti, Al) (C, N) is the main phase. Therefore, the grains in the TiAlN and TiCrAlCN systems are difficult to grow through the element diffusion process among the grains, and the multilayer film with the nanocrystalline composite structure can give consideration to both hardness and toughness and is beneficial to improving the solid particle erosion resistance.

Compared with the prior art, the invention has the following advantages and effects:

the solid particle erosion resistant nanocrystalline multilayer hard film comprises a metal Cr bottom layer, a TiAl transition layer, a TiAlN transition layer and a TiAlCrCN solid particle erosion resistant film layer, wherein the bonding strength of the film and a turbine blade is improved through the metal Cr bottom layer; the TiAlCrCN solid particle erosion resistant film layer plays a role in abrasion resistance, so that the service life of the turbine blade is effectively prolonged.

When the solid particle erosion resistant nanocrystalline multilayer hard film is prepared, the surface of a turbine blade is cleaned firstly, and then a metal Cr bottom layer, a TiAl transition layer, a TiAlN transition layer and a TiAlCrCN solid particle erosion resistant film layer are deposited in sequence by adopting a multi-arc ion plating physical vapor deposition method, so that the operation is convenient, the cost is low, and the nano-crystalline solid particle erosion resistant nanocrystalline multilayer hard film is green and environment-friendly and does not generate any polluted waste water and waste gas.

Drawings

FIG. 1 is a schematic structural diagram of a nanocrystalline multilayer hard film resistant to erosion by solid particles for use in a turbine blade in an example of the present invention.

FIG. 2 is an XRD spectrum of a TiAlCrCN nanocrystalline composite thin film layer resistant to solid particle erosion in an embodiment of the invention.

Detailed Description

The present invention will be described in further detail below by way of examples with reference to the accompanying drawings, which are illustrative of the present invention and are not to be construed as limiting the present invention.

Examples are given.

Referring to fig. 1, the solid particle erosion resistant nanocrystalline multilayer hard film for a turbine blade according to the present invention includes a Cr underlayer 2, a TiAl transition layer 3, a TiAlN transition layer 4, and a TiAlCrCN solid particle erosion resistant thin film layer 5 sequentially deposited on a surface of the turbine blade 1.

The thickness of the Cr underlayer 2 is 0.3 μm, the thickness of the TiAl transition layer 3 is 0.1 μm, the thickness of the TiAlN transition layer 4 is 2 μm, and the thickness of the TiAlCrCN solid particle erosion resistant thin film layer 5 is 10 μm.

The preparation method of the solid particle erosion resistant nanocrystalline multilayer hard film for the turbine blade comprises the following steps:

cleaning the surface of a turbine blade 1, placing the turbine blade 1 on a rotating device in a vacuum chamber for rotating, carrying out plasma cleaning, and then sequentially depositing a Cr bottom layer 2, a TiAl transition layer 3, a TiAlN transition layer 4 and a TiAlCrCN solid particle erosion resistant thin film layer 5 on the surface of the turbine blade 1 by adopting a multi-arc ion plating physical vapor deposition method to finish the preparation of the solid particle erosion resistant nanocrystalline multilayer hard film of the turbine blade 1.

Wherein, in the process of adopting the multi-arc ion plating physical vapor deposition method to deposit the Cr bottom layer 2, Ar gas with the flow rate of 250sccm and the air pressure of 1.4Pa is introduced into the vacuum chamber, the deposition temperature is 300 ℃, Cr is used as a deposition target material in the deposition process, the arc current is 60A, and the bias voltage is 16V.

In the process of depositing the TiAl transition layer 3 by adopting a multi-arc ion plating physical vapor deposition method, Ar gas with the flow rate of 300sccm and the gas pressure of 1.6Pa is introduced into a vacuum chamber, the deposition temperature is 300 ℃, TiAl is used as a deposition target material in the deposition process, the arc current is 60A, and the bias voltage is 18V.

In the process of depositing the oxidation-resistant TiAlN transition layer 4 by adopting a multi-arc ion plating physical vapor deposition method, N is introduced into the vacuum chamber₂A mixed gas of gas and Ar gas, wherein N is₂The flow rate of the gas is 380sccm, the flow rate of the Ar gas is 200sccm, the gas pressure of the mixed gas is 1.6Pa, the deposition temperature is 300 ℃, the TiAl alloy is used as a deposition target material in the deposition process, the arc current is 62A, and the bias voltage is 19V.

In the process of depositing the wear-resistant antifriction TiAlCrCN solid particle erosion resistant film layer 5 by adopting a multi-arc ion plating physical vapor deposition method, N is introduced into the vacuum chamber₂Gas, Ar gas and CH₄A mixed gas of gases, wherein, N₂Flow rate of gas, flow rate of Ar gas and CH₄The flow rate of the gas is respectively 500sccm, 150sccm and 150sccm, the gas pressure of the mixed gas is 1.3Pa, the TiAl alloy is used as a deposition target material in the deposition process, the deposition temperature is 300 ℃, the arc current is 66A, and the bias voltage is 20V; cr is used as a deposition target material, the arc current is 60A, and the bias voltage is 16V.

The rotating device comprises a rotating frame, a supporting plate, a supporting rod and a motor, wherein an output shaft of the motor is connected with the rotating frame, the supporting plate is fixed on the rotating frame through the supporting rod, and the turbine blades are placed on the supporting plate.

As can be seen from FIG. 2, the TiAlCrCN solid particle erosion resistant thin film layer 5 is a nanocrystalline (Ti, Al) (C, N) and nanocrystalline Cr with a face-centered cubic structure₂And N is a two-phase composite structure, wherein the former is a main phase.

Those not described in detail in this specification are well within the skill of the art.

Although the present invention has been described with reference to the above embodiments, it should be understood that the scope of the present invention is not limited thereto, and that various changes and modifications can be made by those skilled in the art without departing from the spirit and scope of the present invention.