Electron beam physical vapor deposition device for preparing thermal barrier coating and method for preparing thermal barrier coating

Abstract

The invention discloses an electron beam physical vapor deposition device for preparing a thermal barrier coating and a method for preparing the thermal barrier coating, the device has the advantages of being simple in structure, easy to overhaul, long in service life and high in power density, and the thermal barrier coating which is uniform in columnar microstructure and excellent in overall performance can be prepared through the device. And the preparation requirements of high performance and high stability of the thermal barrier coating are met.

Description

Technical Field

[0001] The invention belongs to the technical field of electron beam physical vapor deposition preparation of thermal barrier coatings, and in particular relates to an electron beam physical vapor deposition device for preparing thermal barrier coatings and a method for preparing thermal barrier coatings. Background Art

[0002] The aircraft engine is the heart of the aircraft. Its advancement, safety and reliability are important indicators of its technological level. High-pressure turbine blades are the core components of the engine that are most demanding in terms of temperature and load bearing, and are also the shortcoming that restricts the development of the engine. Thermal barrier coating insulation technology is internationally recognized as the most practical way to significantly increase the service temperature of turbine blades. In aircraft engine research, this technology is listed as one of the key technologies for high-performance aircraft engines.

[0003] Electron beam physical vapor deposition (EB-PVD) technology is an important process for preparing thermal barrier coatings. The thermal barrier coatings prepared by this technology have a typical columnar crystal structure and show better strain tolerance. Therefore, it is the most practical way to prepare thermal barrier coatings on turbine rotor blades. Traditional EB-PVD equipment for preparing thermal barrier coatings uses a direct electron gun to heat the target material. It is bulky, complex in structure, difficult to maintain, and susceptible to contamination. In addition, since the direct electron gun of traditional equipment is used to heat the substrate, temperature control is difficult, the condition parameters fluctuate greatly, and the coating quality is difficult to control.

[0004] Therefore, in the field of thermal barrier coating preparation, there is an urgent need for a new device that can improve the quality of coatings and their controllability while reducing costs and maintenance difficulties. Summary of the invention

[0005] In view of the problems that the EB-PVD equipment for preparing thermal barrier coatings in the prior art uses a direct electron gun for heating the target material, which is bulky, complex in structure, difficult to repair and maintain, and easy to be contaminated, and the direct electron gun of traditional equipment is used for substrate heating, temperature control is difficult, condition parameters fluctuate greatly, and coating quality is difficult to control, the purpose of the present invention is to provide an electron beam physical vapor deposition device for preparing thermal barrier coatings and a method for preparing thermal barrier coatings. The device has the advantages of simple structure, easy maintenance, long service life and high power density. The device can produce thermal barrier coatings with uniform columnar microstructure and excellent overall performance, meeting the preparation requirements of high performance and high stability of thermal barrier coatings.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] An electron beam physical vapor deposition device for preparing a thermal barrier coating comprises a first electron gun, a second electron gun, a third electron gun, a driving assembly, a power system 5 and a vacuum chamber;

[0008] The first electron gun, the second electron gun and the third electron gun are respectively detachably connected to the top cover of the vacuum chamber. The top cover is in the shape of an isosceles trapezoid with four sides inverted at 45° right angles. Two through holes are arranged on a 45° inclined plane on one side of the top cover, and flanges are welded at the positions of the through holes for detachably connecting the first electron gun and the second electron gun. The first electron gun and the second electron gun are symmetrically distributed on both sides of the center line of the top cover.

[0009] A through hole is provided on the 45° inclined plane on the other side of the top cover, and a flange is welded at the position of the through hole for detachably connecting the third electron gun, which is distributed on the center line of the top cover; a first observation port and a second observation port are provided on the other two sides of the top cover, and circular glass is provided on the first observation port and the second observation port for observing the progress of the experiment;

[0010] The first electron gun, the second electron gun and the third electron gun all include a high-energy electron beam emitter, a cavity, a cooling device, a focusing device and a high-energy electron beam outlet. The high-energy electron beam emitter is arranged at the top center of the cavity and has a cylindrical shape, and is used to generate a high-energy electron beam to bombard the deposition material.

[0011] The deposition material is placed in a crucible, which is made of ceramic material and is in the shape of a cuboid, and the crucible is placed on a sample table;

[0012] The cavity is in the shape of a rectangular parallelepiped with rounded corners on all sides and is made of a metal shell; a cooling device is arranged on one side of the cavity and uses circulating cooling water to cool the entire electron gun to ensure the smooth operation of the equipment; a focusing device is arranged on the same side of the cooling device and is used to focus the electron beam emitted by the high-energy electron beam emitter so that the high-energy electron beam hits the deposition material;

[0013] When in use, the high-energy electron beam emitter starts to emit electron beams, which are focused on the deposition material through a focusing device. The energy of the electron beam is used to heat and vaporize the deposition material. In a vacuum low-pressure environment, the deposition material vaporizes above the molten pool to form a cloud-like substance. The gas phase atoms usually move in a straight line from the surface of the molten pool to the surface of the turbine blade and are deposited on the surface of the turbine blade to form a thermal barrier coating.

[0014] When in use, each electron gun corresponds to a different target material, and the first electron gun, the second electron gun, and the third electron gun heat their respective materials respectively, so that each target material evaporates at the same time. By independently controlling the power of each electron gun, the evaporation rate of each material is adjusted to achieve co-evaporation of different materials and obtain a uniform alloy or composite coating;

[0015] The vacuum chamber is made of high temperature resistant material and is in a rectangular shape. The top cover is connected to the vacuum chamber by welding. The vacuum chamber is connected to the first support frame by bolts. One side of the vacuum chamber is a rectangular window, which is detachably connected to the movable cover.

[0016] A circular through hole is arranged on one side of the vacuum chamber, a bearing is arranged on the inner side of the through hole, a flange is welded on the outer side of the vacuum chamber, the flange is used to connect with the driving assembly, and the bearing in the through hole is used to perform interference fit connection with the main shaft in the driving assembly, a fixture is arranged on one side of the main shaft, and the fixture is used to fix the turbine blades; the movable cover is in the shape of a rectangular plate, with a raised trapezoidal body in the middle, and the material is a high-temperature resistant alloy, a circular third observation port is arranged at the center of the movable cover, and a fourth observation port is opened on one side of the inclined plane of the movable cover, glass is installed on the third observation port and the fourth observation port, and the third observation port and the fourth observation port are sealed and connected with the glass;

[0017] When in use, the movable cover is disassembled, the turbine blades and deposition materials are placed, and then the movable cover is installed on the window of the vacuum chamber, and the sealing of the window needs to be ensured;

[0018] The other side of the main shaft is connected to the driving assembly. The outer shell of the driving assembly is rectangular in shape, and the gear and the main shaft assembly are assembled inside. A rectangular inspection port is opened on the top of the driving assembly for inspection and adding lubricant. The driving assembly is made of metal material.

[0019] The driving assembly is detachably connected to the second support frame by bolts, and the height of the second support frame is adjusted by the position of the circular through hole of the vacuum chamber to ensure that the main shaft is level;

[0020] The power system has a rectangular shape, and a rotating motor is arranged inside the power system to provide power to the driving assembly so as to rotate the turbine blades; the bottom of the power system is detachably connected to the third support frame by bolts;

[0021] When in use, the motor in the power system provides power to the driving assembly, the driving assembly drives the main shaft to rotate, and the main shaft drives the turbine blades on the fixture to rotate, so that the deposition material is evenly deposited on the turbine blades;

[0022] In order to facilitate manual operation, an operating plane is placed next to the drive assembly and the power system, and a first step and a second step are provided on both sides of the operating plane;

[0023] The operation plane, the first step and the second step are all in a rectangular shape, made of metal, and are connected to the bracket by welding.

[0024] The present invention also relates to a method for preparing a thermal barrier coating, comprising the following steps:

[0025] 1) Install the turbine blades on the fixture, debug the drive components and power system that provide power to see if they are operating normally, and check whether the turbine blades are rotating normally;

[0026] 2) placing the target material required for preparing the thermal barrier coating in a crucible;

[0027] 3) After the work preparation in the vacuum chamber is completed, the movable cover is installed on the vacuum chamber and the seal is checked to see if it is in good condition;

[0028] 4) Turn on the vacuum pump and the exhaust valve to make the pressure in the vacuum chamber reach the pressure required for the experiment, then turn on the power system to make the speed of the rotating motor reach the predetermined speed, and the turbine blades rotate at the predetermined speed;

[0029] 5) Turn on the switches of the first electron gun, the second electron gun and the third electron gun, and the high-energy electron beam emitter on the electron gun starts to emit electron beams. The electron beams are focused on the deposition material through a focusing device, and the energy of the electron beams is used to heat and vaporize the deposition material. In a vacuum low-pressure environment, the deposition material vaporizes above the molten pool to form a cloud-like object, and the gas phase atoms usually move in a straight line from the surface of the molten pool to the surface of the turbine blade and are deposited on the surface of the turbine blade to form a thermal barrier coating;

[0030] 6) Preparing thermal barrier coating;

[0031] 7) After the preparation is completed, turn off the first electron gun, the second electron gun and the third electron gun. After the electron guns are completely turned off, turn off the vacuum pump, and finally open the vacuum chamber to take out the deposited turbine blades.

[0032] Furthermore, for substrates with complex shapes or large areas, the target material can be heated at different angles by multiple electron guns, and the rotation of the substrate can be coordinated to ensure that the evaporated material can evenly cover every area of ​​the substrate.

[0033] Furthermore, during a long deposition process, multiple electron guns can be used alternately to reduce the continuous working time of a single electron gun, thereby extending the life of each electron gun. This approach can effectively reduce the frequency of equipment maintenance and improve system reliability and work efficiency.

[0034] A thermal barrier coating prepared by a method for preparing a thermal barrier coating has the following technical indicators:

[0035] ① Thermal conductivity:

[0036] The thermal conductivity of existing thermal barrier coatings is 2.0-2.5W / (m·K), while the thermal conductivity of the thermal barrier coating prepared by the preparation method of the present invention can achieve 1.0W / (m·K). Lower thermal conductivity means better thermal insulation performance, which can more effectively isolate the base material from the high temperature environment and extend the life of the base material.

[0037] ② Thermal cycle life:

[0038] Existing thermal barrier coatings usually withstand 1000-2000 thermal cycles in thermal cycle tests, while the thermal barrier coating prepared by the preparation method of the present invention can withstand 3000 times, which means that the coating performs better under extreme thermal mechanical stress conditions;

[0039] ③Antioxidant properties:

[0040] The oxidation growth rate of the existing thermal barrier coating in a high-temperature oxidation environment is 1-2 μm / h, while the oxidation growth rate of the thermal barrier coating prepared by the preparation method of the present invention is less than 1 μm / h, which can delay the failure time of the coating and significantly improve the anti-oxidation performance;

[0041] ④Fracture toughness:

[0042] The fracture toughness of existing thermal barrier coatings is usually 1-1.5 MPa·m 1 / 2 The fracture toughness of the thermal barrier coating prepared by the preparation method of the present invention can reach 2MPa·m 1 / 2 , it indicates that the coating has significantly improved resistance to crack propagation and is suitable for more severe mechanical stress conditions;

[0043] ⑤Coating thickness uniformity:

[0044] The standard deviation of thickness uniformity of existing thermal barrier coatings is between ±10-20 μm, while the thermal barrier coating prepared by the preparation method of the present invention can achieve a uniformity of ±5 μm, which means that the coating has advantages in overall structural stability and reduces the problem of local stress concentration;

[0045] ⑥Microstructure advantages:

[0046] The porosity of existing thermal barrier coatings is usually 10-15%, and the pore size range is about 1-5μm, while the thermal barrier coating prepared by the preparation method of the present invention has a porosity of 5-10% and a pore size less than 1μm, which can greatly improve the mechanical properties and anti-stripping ability of the coating.

[0047] Compared with the prior art, the present invention has the following advantages:

[0048] 1. Compared with the traditional EB-PVD equipment for preparing thermal barrier coatings, the electron beam physical vapor deposition device for preparing thermal barrier coatings described in the present invention has a simple structure and is easy to maintain, which greatly reduces the cost. In addition, through the coordinated use of the first electron gun, the second electron gun and the third electron gun, the power density of the device is high and the service life is long.

[0049] 2. The electron beam physical vapor deposition device for preparing a thermal barrier coating described in the present invention can make the prepared thermal barrier coating more uniform by adopting a power system 5 and a drive component, and adopts a multi-station fixture to deposit the thermal barrier coating on batches of turbine blades each time, thereby realizing industrialized production.

[0050] 3. The method for preparing a thermal barrier coating described in the present invention has a uniform columnar microstructure and excellent overall performance. The thermal barrier coating prepared by the device meets the preparation requirements of high performance and high stability of the thermal barrier coating, improves the preparation stability and controllability, and ensures the competitiveness of the device in the field of coating preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a schematic diagram of the overall structure of the electron beam physical vapor deposition device for preparing the thermal barrier coating according to the present invention;

[0052] Figure 2 A schematic diagram of an electron gun of an electron beam physical vapor deposition device for preparing a thermal barrier coating according to the present invention;

[0053] Figure 3 A schematic diagram of preparing a thermal barrier coating according to the present invention;

[0054] Figure 4 A turbine rotor blade with a thermal barrier coating prepared by the present invention;

[0055] Figure 5 The microstructure of the columnar thermal barrier coating ceramic layer prepared by the present invention.

[0056] Among them, the accompanying drawings are marked as:

[0057] 1. First electron gun; 2. Second electron gun; 3. Third electron gun; 4. Driving assembly; 5. Power system; 6. Third support frame; 7. Second support frame; 8. First support frame; 9. First step; 10. Operating plane; 11. Second step; 12. Vacuum chamber; 13. Movable cover; 14. First observation port; 15. Third observation port; 16. Fourth observation port; 17. Second observation port; 18. Flange; 19. Inspection port; 20. Top cover; 30. Deposition material; 31. Crucible; 32. Sample stage; 33. Turbine blades; 101. High-energy electron beam emitter; 102. Cavity; 103. High-energy electron beam outlet; 104. Cooling device; 105. Focusing device. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0059] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0060] Example:

[0061] An electron beam physical vapor deposition device for preparing thermal barrier coatings:

[0062] like Figure 1 As shown, it includes a first electron gun 1, a second electron gun 2, a third electron gun 3, a driving assembly 4, a power system 5 and a vacuum chamber 12;

[0063] The first electron gun 1, the second electron gun 2 and the third electron gun 3 are respectively detachably connected to the top cover 20 of the vacuum chamber 12. The top cover 20 is an isosceles trapezoidal shape with four sides of a rectangular parallelepiped at 45° right angles. Two through holes are arranged on a 45° inclined plane on one side of the top cover 20, and flanges 18 are welded at the positions of the through holes for detachably connecting the first electron gun 1 and the second electron gun 2. The first electron gun 1 and the second electron gun 2 are symmetrically distributed on both sides of the center line of the top cover 20.

[0064] A through hole is provided on the 45° inclined plane on the other side of the top cover 20, and a flange is welded at the position of the through hole for detachably connecting the third electron gun 3, which is distributed on the center line of the top cover 20; a first observation port 14 and a second observation port 17 are provided on the other two sides of the top cover 20, and circular glass is provided on the first observation port 14 and the second observation port 17 for observing the progress of the experiment;

[0065] like Figure 2As shown, the first electron gun 1, the second electron gun 2 and the third electron gun 3 all include a high-energy electron beam emitter 101, a cavity 102, a cooling device 104, a focusing device 105 and a high-energy electron beam outlet 103. The high-energy electron beam emitter 101 is arranged at the top center position in the cavity 102 and has a cylindrical shape, and is used to generate a high-energy electron beam to bombard the deposition material 30;

[0066] like Figure 3 As shown, the deposition material 30 is placed in a crucible 31 , the crucible 31 is made of ceramic material and is in the shape of a cuboid, and the crucible is placed on a sample stage 32 ;

[0067] The cavity 102 is in the shape of a rectangular parallelepiped with rounded corners on all sides and is made of a metal shell; a cooling device 104 is arranged on one side of the cavity 102 and uses circulating cooling water to cool the entire electron gun to ensure the smooth progress of the experiment; a focusing device 105 is arranged on the same side of the cooling device 104 and is used to focus the electron beam emitted by the high-energy electron beam emitter 101 so that the high-energy electron beam hits the deposition material;

[0068] When in use, the high-energy electron beam emitter 101 starts to emit an electron beam, which is focused on the deposition material 30 through the focusing device 105. The energy of the electron beam is used to heat and vaporize the deposition material 30. In a vacuum low-pressure environment, the deposition material 30 vaporizes above the molten pool to form a cloud. The gas phase atoms usually move in a straight line from the surface of the molten pool to the surface of the turbine blade 33 and are deposited on the surface of the turbine blade 33 to form a thermal barrier coating.

[0069] When in use, each electron gun corresponds to a different target material, and the first electron gun 1, the second electron gun 2, and the third electron gun 3 heat their respective materials respectively, so that each target material evaporates at the same time. By independently controlling the power of each electron gun, the evaporation rate of each material can be adjusted to achieve co-evaporation of different materials and obtain a uniform alloy or composite coating.

[0070] For substrates with complex shapes or large areas, the target material can be heated at different angles by multiple electron guns, and the rotation of the substrate can be coordinated to ensure that the evaporated material can evenly cover every area of ​​the substrate.

[0071] During a long deposition process, multiple electron guns can be used alternately to reduce the continuous working time of a single electron gun, thereby extending the life of each electron gun. This method can effectively reduce the frequency of equipment maintenance and improve system reliability and work efficiency.

[0072] The vacuum chamber 12 is made of high temperature resistant material and is in a rectangular shape. The top cover 20 is connected to the vacuum chamber 12 by welding. The vacuum chamber 12 is connected to the first support frame 8 by bolts. One side of the vacuum chamber 12 is a rectangular window, which is detachably connected to the movable cover 13.

[0073] The movable cover 13 is in the shape of a rectangular plate, with a raised trapezoidal body in the middle, and is made of a high-temperature resistant alloy. A circular third observation port 15 is provided at the center of the movable cover 13, and a fourth observation port 16 is provided on one side of the inclined plane of the movable cover 13. Glass is installed on the third observation port 15 and the fourth observation port 16, and the third observation port 15 and the fourth observation port 16 are sealed and connected to the glass;

[0074] When in use, the movable cover 13 is disassembled, the turbine blades 33 and the deposition material 30 are placed, and then the movable cover 13 is installed on the window of the vacuum chamber 12, and the sealing of the window needs to be ensured;

[0075] A circular through hole is provided on one side of the vacuum chamber 12, a bearing is provided inside the through hole, a flange 18 is welded on the outside of the vacuum chamber 12, the flange 18 is used to connect with the drive assembly 4, and the bearing inside the through hole is used to perform interference fit connection with the main shaft in the drive assembly 4, and a fixture is provided on one side of the main shaft, and the fixture is used to fix the turbine blade 33;

[0076] The other side of the main shaft is connected to the driving assembly 4. The outer shell of the driving assembly 4 is rectangular in shape, and the gear and the main shaft assembly are assembled inside. A rectangular inspection port 19 is opened on the top of the driving assembly 4 for inspection and adding lubricant. The driving assembly 4 is made of metal material.

[0077] The driving assembly 4 is detachably connected to the second support frame 7 by bolts, and the height of the second support frame 7 is adjusted by the position of the circular through hole of the vacuum chamber 12 to ensure that the spindle is level;

[0078] The power system 5 is in the shape of a rectangular parallelepiped. A rotating motor is arranged inside the power system 5 to provide power to the driving assembly 4 so as to rotate the turbine blades 33. The bottom of the power system 5 is detachably connected to the third support frame 6 by bolts.

[0079] In order to facilitate manual operation, an operation plane 10 is placed next to the driving assembly 4 and the power system 5, and a first step 9 and a second step 11 are provided on both sides of the operation plane 10;

[0080] The operation plane 10, the first step 9 and the second step 11 are all in the shape of a cuboid, made of metal, and are welded to the bracket;

[0081] When in use, the motor in the power system 5 provides power to the driving assembly 4 , the driving assembly 4 drives the main shaft to rotate, and the main shaft drives the turbine blades 33 on the fixture to rotate, so that the deposition material 30 is evenly deposited on the turbine blades 33 .

[0082] Embodiment 2:

[0083] A method for preparing a thermal barrier coating comprises the following steps:

[0084] 1) Install the turbine blade 33 on the fixture, and debug whether the driving assembly 4 and the power system 5 that provide power are operating normally, and check whether the turbine blade 33 rotates normally;

[0085] 2) placing the target material required for preparing the thermal barrier coating in the crucible 31;

[0086] 3) After the work preparation in the vacuum chamber 12 is completed, the movable cover 13 is installed on the vacuum chamber 12 and the sealing is checked to see if it is in good condition;

[0087] 4) Open the vacuum pump and the exhaust valve to make the pressure in the vacuum chamber 12 reach the pressure required for the experiment, then turn on the power system 5 to make the speed of the rotating motor reach a predetermined speed, and the turbine blades 33 rotate at the predetermined speed;

[0088] 5) Turn on the switches of the first electron gun 1, the second electron gun 2 and the third electron gun 3, and the high-energy electron beam emitter 101 on the electron gun starts to emit electron beams, and the electron beams are focused on the deposition material 30 through the focusing device 105, and the energy of the electron beams is used to heat and vaporize the deposition material 30. In the vacuum low-pressure environment, the deposition material 30 vaporizes above the molten pool to form a cloud, and the gas phase atoms usually move in a straight line from the surface of the molten pool to the surface of the turbine blade 33 and are deposited on the surface of the turbine blade 33 to form a thermal barrier coating;

[0089] 6) Preparing thermal barrier coating;

[0090] 7) After the preparation is completed, the first electron gun 1, the second electron gun 2 and the third electron gun 3 are turned off. After the electron guns are completely turned off, the vacuum pump is turned off, and finally the vacuum chamber 12 is opened to take out the deposited turbine blades 33.

[0091] The present embodiment provides a thermal barrier coating for a turbine blade prepared by an electron beam physical vapor deposition device for preparing a thermal barrier coating. Figure 4 As shown, the columnar thermal barrier coating is Figure 5 shown.

[0092] As can be seen from Figure 4, the thermal barrier coating deposited on the turbine blade is very uniform and of stable and reliable quality. At the same time, as can be seen from Figure 5, the columnar microstructure of the thermal barrier coating is uniform and the overall performance is excellent, which can meet the preparation requirements of high performance and high stability of the thermal barrier coating.

[0093] Results and Discussion:

[0094] The present invention aims to protect an electron beam physical vapor deposition device for preparing a thermal barrier coating and a method for preparing a thermal barrier coating, comprising pre-treating a thermal barrier coating sample of a turbine blade; preparing a thermal barrier coating by using the device according to corresponding steps; obtaining mechanical property data of the thermal barrier coating sample of the turbine blade, the mechanical property data including: cross-sectional porosity of the thermal barrier coating, thickness of the thermal barrier coating, cross-sectional density of the thermal barrier coating, elastic modulus of the thermal barrier coating and hardness of the thermal barrier coating; the prepared thermal barrier coating has the following technical indicators: ① thermal conductivity: can achieve 1.0W / (m·K); ② thermal cycle life: can withstand 3000 times; ③ oxidation resistance: oxidation growth rate is less than 1μm / h; ④ fracture toughness: reaches 2MPa·m 1 / 2 ; ⑤Coating thickness uniformity: can achieve uniformity of ±5μm;

[0095] ⑥ Microstructure advantages: porosity is 5-10%, and pore size is less than 1μm; the mechanical properties data is imported into Matlab, and a three-dimensional model of the turbine blade thermal barrier coating is established based on the two-dimensional interpolation method or the linear interpolation method to characterize the overall mechanical properties of the turbine blade thermal barrier coating and the mechanical properties of the local area.

[0096] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. An electron beam physical vapor deposition device for preparing a thermal barrier coating, characterized in that: It comprises a first electron gun (1), a second electron gun (2), a third electron gun (3), a driving assembly (4), a power system (5) and a vacuum chamber (12); The first electron gun (1), the second electron gun (2) and the third electron gun (3) are respectively detachably connected to a top cover (20) of the vacuum chamber (12); the top cover (20) is in the shape of an isosceles trapezoid with four sides inverted at 45° right angles; two through holes are arranged on a 45° inclined plane on one side of the top cover (20); flanges (18) are welded at the positions of the through holes for detachably connecting the first electron gun (1) and the second electron gun (2); the first electron gun (1) and the second electron gun (2) are symmetrically distributed on both sides of the center line of the top cover (20); A through hole is provided on the 45° inclined plane on the other side of the top cover (20), and a flange (18) is welded at the position of the through hole for detachably connecting the third electron gun (3), and the third electron gun (3) is distributed on the center line of the top cover (20); a first observation port (14) and a second observation port (17) are provided on the other two sides of the top cover (20), and circular glass is provided on the first observation port (14) and the second observation port (17) for observing the progress of the experiment; The first electron gun (1), the second electron gun (2) and the third electron gun (3) all comprise a high-energy electron beam emitter (101), a cavity (102), a cooling device (104), a focusing device (105) and a high-energy electron beam outlet (103); the high-energy electron beam emitter (101) is arranged at the top center position in the cavity (102) and has a cylindrical shape, and is used to generate a high-energy electron beam to bombard the deposition material (30); During operation, each electron gun corresponds to a different target material, and the first electron gun (1), the second electron gun (2), and the third electron gun (3) heat their respective materials respectively, so that each target material evaporates at the same time. By independently controlling the power of each electron gun, the evaporation rate of each material is adjusted to achieve co-evaporation of different materials, thereby obtaining a uniform alloy or composite coating; The deposition material (30) is placed in a crucible (31), the crucible (31) is made of ceramic material and is in the shape of a rectangular parallelepiped, and the crucible is placed on a sample table (32); The cavity (102) is in the shape of a rectangular parallelepiped with rounded corners on all sides and is made of a metal shell; a cooling device (104) is arranged on one side of the cavity (102) and uses circulating cooling water to cool the entire electron gun to ensure smooth operation of the equipment; a focusing device (105) is arranged on the same side of the cooling device (104) and is used to focus the electron beam emitted by the high-energy electron beam emitter (101) so that the high-energy electron beam hits the deposition material; During operation, the high-energy electron beam emitter (101) starts to emit an electron beam, which is focused on the deposition material (30) by the focusing device (105). The energy of the electron beam is used to heat and vaporize the deposition material (30). In a vacuum low-pressure environment, the deposition material (30) vaporizes above the molten pool to form a cloud-like object, and the gas phase atoms move in a straight line from the surface of the molten pool to the surface of the turbine blade (33) and are deposited on the surface of the turbine blade (33) to form a thermal barrier coating. The vacuum chamber (12) is made of high temperature resistant material and is in a rectangular shape. The top cover (20) is connected to the vacuum chamber (12) by welding. The vacuum chamber (12) is connected to the first support frame (8) by bolts. One side of the vacuum chamber (12) is a rectangular window, which is detachably connected to the movable cover (13). A circular through hole is provided on one side of the vacuum chamber (12), a bearing is provided on the inner side of the through hole, a flange (18) is welded on the outer side of the vacuum chamber (12), the flange (18) is used to connect with the drive assembly (4), and the bearing in the through hole is used to perform interference fit connection with the main shaft in the drive assembly (4), a fixture is provided on one side of the main shaft, and the fixture is used to fix the turbine blade (33); the movable cover (13) is in the shape of a rectangular plate, with a raised trapezoidal body in the middle, and the material is a high-temperature resistant alloy, a circular third observation port (15) is provided at the center of the movable cover (13), and a fourth observation port (16) is opened on one side of the inclined plane of the movable cover (13), glass is installed on the third observation port (15) and the fourth observation port (16), and the third observation port (15) and the fourth observation port (16) are sealed and connected to the glass; During operation, the movable cover (13) is disassembled, the turbine blades (33) and the deposition material (30) are placed, and then the movable cover (13) is installed on the window of the vacuum chamber (12), and the sealing of the window is ensured; The other side of the main shaft is connected to the driving assembly (4). The outer shell of the driving assembly (4) is rectangular in shape, and the gear and the main shaft assembly are assembled inside. A rectangular inspection port (19) is opened on the top of the driving assembly (4) for inspection and adding lubricant. The driving assembly (4) is made of metal material. The driving assembly (4) is detachably connected to the second support frame (7) by bolts, and the height of the second support frame (7) is adjusted by the position of the circular through hole of the vacuum chamber (12) to ensure that the main shaft is level; The power system (5) has a rectangular shape, and a rotating motor is arranged inside the power system (5) for providing power to the driving assembly (4), thereby rotating the turbine blades (33); the bottom of the power system (5) is detachably connected to the third support frame (6) by bolts; During operation, the motor in the power system (5) provides power to the driving component (4), the driving component (4) drives the main shaft to rotate, and the main shaft drives the turbine blades (33) on the fixture to rotate, so that the deposition material (30) is evenly deposited on the turbine blades (33); An operating plane (10) is placed beside the driving assembly (4) and the power system (5) to facilitate manual operation, and a first step (9) and a second step (11) are arranged on both sides of the operating plane (10); The operating plane (10), the first step (9) and the second step (11) are all in a rectangular shape, made of metal, and are connected to the bracket by welding.

2. A method for preparing a thermal barrier coating using an electron beam physical vapor deposition device for preparing a thermal barrier coating according to claim 1, characterized in that: The steps include: 1) Install the turbine blade (33) on the fixture, and debug the driving assembly (4) and the power system (5) that provide power to check whether they are operating normally, and check whether the turbine blade (33) rotates normally; 2) placing a target material required for preparing a thermal barrier coating in a crucible (31); 3) After the work preparation in the vacuum chamber (12) is completed, the movable cover (13) is installed on the vacuum chamber (12) and checked whether the seal is good; 4) opening the vacuum pump and the exhaust valve to make the pressure in the vacuum chamber (12) reach the pressure required for the experiment, and then opening the power system (5) to make the rotation speed of the rotating motor reach a predetermined rotation speed, and the turbine blades (33) rotate at the predetermined rotation speed; 5) Turning on the switches of the first electron gun (1), the second electron gun (2) and the third electron gun (3), the high-energy electron beam emitter (101) on the electron gun starts to emit electron beams, the electron beams are focused on the deposition material (30) through the focusing device (105), the energy of the electron beams is used to heat and vaporize the deposition material (30), in a vacuum low-pressure environment, the deposition material (30) vaporizes above the molten pool to form a cloud, and the gas phase atoms usually move in a straight line from the surface of the molten pool to the surface of the turbine blade (33) and are deposited on the surface of the turbine blade (33) to form a thermal barrier coating; 6) Preparing thermal barrier coating; 7) After the preparation is completed, the first electron gun (1), the second electron gun (2) and the third electron gun (3) are turned off, and after the electron guns are completely turned off, the vacuum pump is turned off, and finally the vacuum chamber (12) is opened to take out the deposited turbine blade (33); The prepared thermal barrier coating has the following technical indicators: ① Thermal conductivity: can achieve 1.0W / (m·K); ② Thermal cycle life: can withstand 3000 times; ③ Antioxidant performance: The oxidation growth rate is less than 1μm / h; ④Fracture toughness: up to 2MPa·m 1 / 2 ; ⑤Coating thickness uniformity: can achieve uniformity of ±5μm; ⑥ Microstructure advantages: porosity is 5-10%, and pore size is less than 1μm.

3. The method for preparing a thermal barrier coating according to claim 2, characterized in that: For substrates with complex shapes or large areas, the target material is heated at different angles by multiple electron guns, and the rotation of the substrate is coordinated to ensure that the evaporated material can evenly cover every area of ​​the substrate.

4. The method for preparing a thermal barrier coating according to claim 2, characterized in that: During a long deposition process, multiple electron guns are used alternately to reduce the continuous working time of a single electron gun, thereby extending the life of each electron gun.

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