Plasma jet diagnostic device, diagnostic method and plasma spray physical vapor deposition apparatus

Abstract

The application discloses a kind of plasma jet diagnostic device, diagnostic method and plasma spraying physical vapor deposition equipment, it is related to nondestructive testing and special processing process diagnostic technical field.The provided plasma jet diagnostic device, including: optical path unit, camera unit and computer unit;Wherein optical path unit includes light intensity adjusting piece and narrowband filter, camera unit includes lens and camera, camera is electrically connected with computer unit;Along the direction perpendicular to the side of plasma jet and gradually away from plasma jet, light intensity adjusting piece, narrowband filter, lens and camera are sequentially arranged, plasma jet sequentially passes through light intensity adjusting piece and narrowband filter, then passes through lens and camera and obtains the image to be measured, and the imaging picture in camera is analyzed by computer unit.The present application can solve the defect problem that current PS-PVD process monitoring lacks jet intuitive diagnostic method, and the overall characterization of jet field and energy field can be realized.

Description

Technical Field

[0001] This application belongs to the technical field of non-destructive testing and special processing technology diagnosis, especially to the field of process diagnosis of complex gas-solid-liquid three-phase composite plasma physical vapor deposition, specifically involving a plasma jet diagnostic device, diagnostic method and plasma spraying physical vapor deposition equipment. Background Technology

[0002] Plasma spray-physical vapor deposition (PS-PVD) technology utilizes the pressure difference expansion characteristics of plasma jets under ultra-low pressure to form expanded plasma jets with a length >2m. The jets are characterized by high speed and temperature gradient decay, enabling rapid vaporization of powder in the jets and gas-solid-liquid three-phase composite controlled deposition. In addition, it also takes into account the characteristics of high efficiency and non-line-of-sight deposition deflection (high-speed jet). The prepared coatings have columnar / quasi-columnar structures, which can meet the performance requirements of thermal barrier coatings such as high deposition rate, high thermal insulation, and long life, and therefore have attracted widespread attention.

[0003] Because PS-PVD employs the principle of ionization deposition, unlike traditional atomic evaporation and molten liquid phase deposition, the proportion and concentration of the gas phase determine the deposition quality of the coating. Currently, the only way to optimize the coating structure and performance is to adjust the main process parameters and conduct extensive testing and analysis to establish the correlation between coating deposition parameters, powder material properties, and coating microstructure and performance. However, while this method can solve the optimization problem, it cannot effectively identify the impact of process parameter fluctuations and process stability on the coating microstructure, performance, and lifespan. In related technologies, PS-PVD process monitoring often uses optical emission spectrometry (OES) to characterize the intensity of specific wavelength spectra and analyze the energy of the plasma jet and the gas phase concentration of the evaporated material. However, this method can only characterize a single point or a corresponding small area and cannot characterize the overall flow field.

[0004] In view of this, those skilled in the art have long sought a holistic characterization method for the jet field and energy field to improve the current lack of intuitive diagnostic methods for jets. Summary of the Invention

[0005] The purpose of this application is to provide a plasma jet diagnostic device, diagnostic method, and plasma spraying physical vapor deposition equipment, which can alleviate the current problem of lack of intuitive diagnostic methods for jet monitoring in PS-PVD processes, and can realize the overall characterization of the jet field and energy field.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows: According to one aspect of this application, an embodiment of this application provides a plasma jet diagnostic device for use in a plasma spraying physical vapor deposition apparatus, the plasma jet diagnostic device comprising: an optical path unit, a camera unit, and a computer unit; The optical path unit includes an intensity adjustment component and a narrowband filter, the camera unit includes a lens and a camera, and the camera is electrically connected to the computer unit. Along a direction perpendicular to the side of the plasma jet and gradually away from the plasma jet, the light intensity adjustment device, the narrowband filter, the lens, and the camera are arranged in sequence. The light intensity adjustment device is used to adjust the light intensity, and the narrowband filter is used to acquire wavelength light of a preset band. The image to be tested is obtained through the lens and the camera, and the image in the camera is analyzed by the computer unit.

[0007] In some alternative embodiments, the optical path unit further includes a filter ring, and the light intensity adjustment element and the narrowband filter are both installed inside the filter ring.

[0008] In some alternative embodiments, the light intensity adjustment element is vertically mounted inside the filter ring.

[0009] In some alternative implementations, the narrowband filter is mounted vertically or at an angle within the filter ring.

[0010] In some alternative embodiments, the light intensity adjustment element includes a neutral density filter, the attenuation rate of which is adjustable in the range of 1% to 20%.

[0011] In some alternative implementations, the filter ring is connected to the lens via an adapter ring.

[0012] In some alternative implementations, the filter ring is threadedly connected to the lens.

[0013] In some alternative embodiments, the filter ring has at least two mounting slots inside for mounting the light intensity adjustment element and the narrowband filter.

[0014] In some alternative embodiments, the light intensity adjustment element and the narrowband filter are respectively threadedly connected to the filter ring.

[0015] In some alternative embodiments, the size of the light intensity adjustment element is ≥50mm.

[0016] In some alternative implementations, the narrowband filter has a size ≥50mm.

[0017] In some alternative implementations, the focusing distance of the lens is ≥1500mm.

[0018] In some alternative embodiments, the field of view of the lens ranges from 22 degrees 50 minutes to 5 degrees 20 minutes, or the minimum field of view of the lens is less than 5 degrees 20 minutes.

[0019] In some alternative implementations, the camera unit further includes an aperture, and the lens is connected to the aperture.

[0020] In some alternative implementations, the camera includes a CCD camera.

[0021] In some alternative implementations, the camera is adapted to operate at a temperature of ≥40°C.

[0022] In some alternative implementations, the side axis of the camera is mounted perpendicular to the plasma jet axis and remains horizontal and fixed.

[0023] In some alternative implementations, the camera unit including the lens and the camera has a maximum lateral field of view of ≥400mm and a longitudinal field of view of ≥200mm.

[0024] In some optional embodiments, the narrowband filter includes at least three narrowband filters, the center wavelengths of the at least three narrowband filters being 384nm, 587.5nm, and 696.5nm, respectively; the bandwidth of the narrowband filter is 1nm to 15nm, and the cutoff band of the narrowband filter is 200nm to 1200nm.

[0025] According to another aspect of this application, embodiments of this application provide a plasma jet diagnostic method applied to the aforementioned plasma jet diagnostic device, the method comprising: Wavelength separation of components within the jet during plasma spraying physical vapor deposition is achieved using narrowband filters of different wavelengths. The light intensity of each component can be adjusted during imaging by combining the light intensity adjustment device and the exposure time in the camera unit; The automatic analysis module in the computer unit analyzes the grayscale values ​​of the imaging images to characterize the energy field distribution characteristics of the plasma jet and the gas phase concentration field distribution characteristics of the deposited material in the jet.

[0026] In some alternative embodiments, the light intensity adjustment element includes a neutral density filter, the camera unit includes an aperture connected to the lens, and the camera includes a CCD camera; the combined attenuation rate of the exposure combination in the neutral density filter, the aperture, and the CCD camera is adapted to keep the gray value of the plasma jet within a preset range under each operating condition.

[0027] In some optional implementations, the automatic analysis module in the computer unit performs analysis using grayscale values ​​by: multiplying the electrical signal with a conversion coefficient using an analog-to-digital converter to convert it into a grayscale signal, and then performing analysis based on the mathematical relationship between the grayscale values ​​and the overall amplitude and brightness.

[0028] According to another aspect of this application, an embodiment of this application provides a plasma spraying physical vapor deposition apparatus, which includes the aforementioned plasma jet diagnostic device.

[0029] Implementing the technical solution of the present invention has at least the following beneficial effects: In this embodiment, the provided plasma jet diagnostic device includes an optical path unit, a camera unit, and a computer unit. The optical path unit, composed of an intensity adjustment component and a narrowband filter, can comprehensively control the optical path to achieve imaging of different plasma gas ionization flow fields and different material fields. By utilizing the plasma ionization components and the emission spectra of evaporated and molten materials, it can calibrate and image individual components, realize the distribution characteristics of the plasma jet energy field, the distribution characteristics of the gas phase concentration field of the deposited material in the jet, and the regularity analysis of the above characteristics and changing trends at different locations. This device and method have the advantages of simple structure and direct and rapid extraction of information within the field of view. It can be used for process optimization and rapid diagnosis of processing quality, thereby alleviating the current deficiency of lacking intuitive jet diagnostic methods in PS-PVD process monitoring, and realizing the overall characterization of the jet field and energy field.

[0030] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the plasma jet diagnostic device provided in the embodiments of this application; Figure 2 A schematic diagram of the main parameters of the CCD camera in the plasma jet diagnostic device provided in the embodiments of this application; Figure 3 This is a schematic diagram of the computing unit composition in the plasma jet diagnostic device provided in the embodiments of this application; Figure 4 This is a schematic diagram of the structure of the plasma spraying physical vapor deposition equipment provided in the embodiments of this application; Figure 5 The following are images, grayscale images, and positional patterns of the jet provided in the embodiments of this application; Figure 6 Ar gas phase distribution diagram and OES result comparison diagram before and after jet powder feeding are provided for embodiments of this application; Figure 7The He gas phase distribution diagram and OES result comparison diagram before and after jet powder feeding are provided for the embodiments of this application; Figure 8 The Zr gas phase distribution diagram and OES result comparison diagram after powder flow are provided in the embodiments of this application.

[0032] Explanation of reference numerals in the attached figures: 1-Plasma jet diagnostic device; 101-Filter ring; 102-Light intensity adjustment component; 103-Narrowband filter; 104-Adapter ring; 105-Lens; 106-Aperture; 107-Camera (CCD camera); 108-Computer unit; 171 - Exposure time; 172 - Resolution; 173 - Frame rate; 174 - Aperture F; 181 - Automatic analysis module; 182 - Camera control module; 2-Spray gun; 3-Six-axis robotic arm; 4-Vacuum tank; 5-Vacuum pump; 6-Powder feeder; 7-Protective gas source; 8-Water chiller; 9-Power distribution cabinet; 10-Industrial computer; 11-Control system. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the ranges, the endpoint values ​​of the ranges, or individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0035] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0036] The embodiments of this application will be described in detail below with reference to the accompanying drawings and specific examples and application scenarios.

[0037] Thermal barrier coatings (TBCs) are a key scientific technology in the development of advanced aero-engines. TBCs can significantly reduce the surface temperature of turbine blade alloys, thereby greatly extending their service life. They are one of the core key manufacturing technologies for the hot-end components of modern gas turbine engines and have attracted much attention. The traditional mainstream processing techniques for TBCs mainly include atmospheric plasma spraying (APS) and electron beam physical vapor deposition (EB-PVD), both of which are line-of-sight deposition techniques. APS utilizes a high-energy plasma beam to heat and accelerate powder particles, melting and softening them to impact the substrate at a certain velocity, forming a flattened, stacked layered structure coating. The resulting TBCs have advantages such as high processing efficiency and low thermal conductivity, but insufficient strain tolerance. EB-PVD technology uses a high-energy electron beam to evaporate material rods, forming atomic-level vapor. This vapor is then condensed onto the surface of a high-temperature substrate at a low speed, continuously growing a columnar structure coating with high strain tolerance on the part surface. However, it suffers from low deposition efficiency, high cost, and poor thermal insulation. Therefore, those skilled in the art have been searching for process technologies that can combine the advantages of both to achieve stable preparation of coating structures with higher deposition efficiency, higher thermal insulation, and longer lifespan. Compared to APS and EB-PVD technologies, plasma spraying vapor phase physical deposition (PS-PVD) technology combines high efficiency and non-line-of-sight deposition deflection (high-speed jet) characteristics, and the prepared coatings have a columnar / quasi-columnar structure, which can meet the performance requirements of thermal barrier coatings such as high deposition rate, high thermal insulation, and long lifespan.

[0038] In related technologies, PS The research and development of PVD has been rapid, but some problems remain to be solved in the actual workpiece spraying process. For example, because PS-PVD uses the principle of ionization deposition, unlike traditional atomic evaporation and molten liquid phase deposition, the proportion and concentration of the gas phase determine the deposition quality of the coating. Currently, the only way to optimize the coating structure and performance is to adjust the main process parameters and conduct extensive testing and analysis to establish the correlation between coating deposition parameters, powder material properties, and coating microstructure and performance. However, while this method can solve the optimization problem, it cannot effectively identify the impact of process parameter fluctuations and process stability on coating microstructure, performance, and lifespan. Traditional APS processes use CCD monitoring, including particle temperature and velocity measurements, to characterize process stability, but this is not suitable for vapor phase deposition. PS-PVD process monitoring often uses optical emission spectrometry (OES) to characterize the intensity of specific wavelength spectra and analyze the energy of the plasma jet and the gas phase concentration of the evaporated material. However, this method can only characterize a single point or a corresponding small area and cannot characterize the overall flow field. Therefore, those skilled in the art have been looking for a method to characterize the jet field and energy field holistically to overcome the current lack of intuitive jet diagnostic methods.

[0039] In view of this, the inventors of this application, through extensive research, provide a plasma jet diagnostic device, a plasma jet diagnostic method, and a plasma spray physical vapor deposition equipment. This allows for the analysis of the energy field distribution characteristics of the plasma jet, the gas phase concentration field distribution characteristics of the deposited material in the jet, and the regularity of these characteristics and their changing trends at different locations, thereby overcoming the aforementioned deficiencies in related technologies. The following is a detailed description of this application.

[0040] refer to Figures 1 to 4 As shown, in some embodiments, this application provides a plasma jet diagnostic device 1 for plasma spraying physical vapor deposition equipment. The plasma jet diagnostic device 1 includes: an optical path unit, a camera unit, and a computer unit 108. The optical path unit includes a light intensity adjustment element 102 and a narrowband filter 103, and the camera unit includes a lens 105 and a camera 107. The camera 107 is electrically connected to the computer unit 108. Along a direction perpendicular to the side of the plasma jet and gradually away from the plasma jet, a light intensity adjustment element 102, a narrow band filter 103, a lens 105, and a camera 107 are arranged in sequence. The light intensity adjustment element 102 is used to adjust the light intensity, and the narrow band filter 103 is used to acquire wavelength light of a preset band. After the plasma jet passes through the light intensity adjustment element 102 and the narrow band filter 103 in sequence, it passes through the lens 105 and the camera 107 to obtain the image to be tested. The computer unit 108 analyzes the image captured by the camera 107.

[0041] The plasma jet diagnostic device 1 of this embodiment can be used in a plasma spraying physical vapor deposition (PS-PVD) device. The PS-PVD device may include the device body and the plasma jet diagnostic device 1 provided in this embodiment. The device body may be a known device in the related art, such as a spray gun for generating plasma jets. This embodiment does not limit the specific structure or type of the device body.

[0042] The plasma jet diagnostic device 1 and the PS-PVD equipment including the plasma jet diagnostic device 1 provided in this embodiment can be used in the preparation of thermal barrier coatings and can be used to improve the performance of PS-PVD coatings. The utilization rate of plasma jets in PVD equipment reduces equipment operating costs, thereby improving the quality of the prepared thermal barrier coatings and ensuring the yield of coated products.

[0043] The plasma jet diagnostic device 1 includes an optical path unit, a camera unit, and a computer unit 108 arranged sequentially along a direction perpendicular to the side of the plasma jet and gradually away from the plasma jet. That is, it includes an optical path unit, a camera unit, and a computer unit 108 arranged from near to far along the side of the PS-PVD jet. The plasma jet passes through the optical path unit and the camera unit in sequence, and the camera unit and the computer unit 108 can be connected by a signal.

[0044] The plasma jet diagnostic device 1 can comprehensively control the optical path through an optical path unit composed of light intensity adjustment components 102, such as neutral density filters or attenuators, and narrowband filters 103, to achieve imaging of different plasma gas ionization flow fields and material fields of different materials. The diagnostic method of this plasma jet diagnostic device 1 mainly utilizes the plasma ionization components and the emission spectra of evaporated and molten materials to achieve individual component calibration and imaging. The computer unit 108 includes an automatic analysis module 181, which possesses the characteristics of the plasma jet energy field distribution, the gas phase concentration field distribution characteristics of the deposited material in the jet, and the regularity analysis of the above characteristics and changing trends at different locations. It can obtain information such as complex energy and material concentration within the jet in the spraying deposition area. This device and method have advantages such as simple structure and direct and rapid extraction of information within the field of view. It can be used for process optimization and rapid diagnosis of processing quality, thereby alleviating the current deficiency of lacking intuitive jet diagnostic methods in PS-PVD process monitoring, and can achieve overall characterization of the jet field and energy field.

[0045] In some embodiments, the light intensity modulator 102 includes a neutral density filter.

[0046] In some embodiments, the optical path unit further includes a filter ring 101, and light intensity adjustment components 102, such as a neutral density filter and a narrowband filter 103, are all installed within the filter ring 101. This optical path unit mainly includes a filter ring 101, light intensity adjustment components 102 such as a neutral density filter, and a narrowband filter 103. Optionally, the filter ring 101 is connected to the lens 105 via an adapter ring 104.

[0047] In some embodiments, camera 107 includes a CCD camera.

[0048] In some embodiments, the camera unit further includes an aperture 106, with a lens 105 connected to the aperture 106. The camera unit mainly includes a lens 105, an aperture 106, and a camera 107.

[0049] Therefore, in the plasma jet diagnostic device 1 of this embodiment, the optical path unit and the camera unit, from near to far from the object being collected, are, in order, a light intensity adjustment component 102 such as a neutral density filter, a narrow band filter 103, a lens 105, an aperture 106, and a camera 107. The neutral density filter and the narrow band filter 103 can be installed inside the filter ring 101. The filter ring 101 can be connected to the lens 105 through an adapter ring 104. The lens 105 is also connected to the aperture 106. The camera 107, such as a CCD camera, can be connected to a computer unit 108 equipped with an image acquisition card via gigabit broadband. Therefore, wavelength separation of each component in the PS-PVD jet can be achieved by using narrowband filters 103 with different center wavelengths, and light intensity adjustment for imaging of each component can be achieved by combining neutral density filters, aperture 106 and exposure time 171 in CCD camera 107. The grayscale value of the image can be analyzed by automatic analysis software in computer unit 108 to characterize the energy field distribution characteristics of plasma jet and the gas phase concentration field distribution characteristics of deposited material in jet.

[0050] Optionally, refer to Figure 2 The main parameters of the CCD camera 107 in this embodiment include: exposure time 171, resolution 172, frame rate 173, and aperture F 174.

[0051] Optionally, refer to Figure 3 The computer unit 108 in this embodiment may include an automatic analysis module 181 and a camera control module 182. The specific working principle of these modules is known to those skilled in the art and will not be described in detail here.

[0052] Optionally, the attenuation rate of the neutral density filter can be adjusted within the range of 1% to 20%. The light intensity adjustment element 102, such as the neutral density filter, can be vertically mounted in the filter ring 101.

[0053] In some embodiments, the narrowband filter 103 is mounted vertically or at a certain angle in the filter ring 101; this facilitates the application of the narrowband filter 103 in different application methods (different incident angles).

[0054] In some embodiments, the filter ring 101 has at least two mounting slots inside for mounting the light intensity adjustment element 102 and the narrowband filter 103.

[0055] Optionally, the light intensity adjustment element 102 and the narrowband filter 103 are threadedly connected to the filter ring 101.

[0056] In this embodiment, two or more mounting slots are provided inside the filter ring 101 for mounting light intensity adjustment components 102, such as neutral density filters and narrowband filters 103. The ends of the mounting slots may be threaded for easy installation.

[0057] In order to enable the light intensity adjustment component 102, such as the neutral density filter and the narrow band filter 103, to be threadedly connected to the mounting bayonet in the filter ring 101, a thread can be made at the end of the mounting bayonet to achieve a threaded connection, which is convenient for disassembly and maintenance.

[0058] In this embodiment, the filter ring 101 is connected to the lens 105 via an adapter ring 104; optionally, the filter ring 101 is threadedly connected to the lens 105.

[0059] The light intensity adjustment components 102, such as the neutral density filter and the narrow band filter 103, are installed inside the filter ring 101 through mounting bayonet. The filter ring 101 can be directly threaded to the outer opening of the lens 105 to ensure that the entire optical path system is sealed and to prevent other light from entering the lens 105 and causing interference.

[0060] For example, the two ends of the adapter ring 104 can be threaded, and the two ends of the adapter ring 104 can be connected to the filter ring 101 and the lens 105 respectively through the threads, thereby making the filter ring 101 and the lens 105 threadedly connected. The two ends of the adapter ring 104 are threaded, and the dimensions of the two ends should be consistent with those of the filter ring 101 and the lens 105 respectively.

[0061] In some embodiments, the light intensity adjustment element 102, such as a neutral density filter, has a size ≥50mm.

[0062] In some embodiments, the narrowband filter 103 has a size ≥ 50 mm.

[0063] It should be noted that the light intensity adjustment element 102 and the narrowband filter 103 can be circular or square. When they are circular, the above dimensions refer to the diameter; when they are square, the above dimensions refer to the side length. Similarly, when they are other shapes, the above dimensions mainly refer to the side length.

[0064] In this embodiment, the diameter or side length (corresponding to) of the neutral density filter and the narrowband filter 103 should be greater than or equal to 50mm to prevent the filter ring 101 from obstructing the imaging field of view due to its small size.

[0065] In some embodiments, the focusing distance of lens 105 is ≥1500mm.

[0066] In this embodiment, the focusing distance of the lens 105 is made not less than 1500mm to adapt to the distance limitations imposed by the vacuum tank and the double-layered angled glass.

[0067] In some embodiments, the field of view of lens 105 is between 22 degrees 50 minutes and 5 degrees 20 minutes, or the minimum field of view of lens 105 is less than 5 degrees 20 minutes.

[0068] In this embodiment, the field of view of the lens 105 is set to 22 degrees 50 minutes to 5 degrees 20 minutes or less to meet the requirements of the narrowband filter 103 for the incident light angle and prevent the center wavelength from shifting.

[0069] In some embodiments, camera 107 is a CCD camera suitable for operation at temperatures ≥40°C. The CCD camera should be able to operate at a temperature not lower than 40°C to prevent excessive temperature due to jet thermal radiation.

[0070] Optionally, the side axis of the camera 107, such as a CCD camera, is mounted perpendicular to the plasma jet axis and kept horizontal and fixed.

[0071] In this embodiment, the side axis of the CCD camera 107 is installed perpendicular to the jet axis and must be kept horizontal and fixed. The installation height can be about 1500mm to accommodate the height of the observation window on the vacuum tank.

[0072] In some embodiments, the camera unit including lens 105 and camera 107, that is, the imaging system consisting of lens 105 and camera 107, has a maximum horizontal field of view of ≥400mm and a vertical field of view of ≥200mm.

[0073] The imaging system consisting of the aforementioned lens 105 and camera needs to have a maximum lateral field of view of no less than 400 mm in order to complete the imaging of the jet in the deposition section (900-1300 mm), and a longitudinal field of view of no less than 200 mm in order to obtain sufficient data for analysis.

[0074] In some embodiments, the narrowband filter 103 includes at least three narrowband filters 103, with center wavelengths of 384 nm, 587.5 nm, and 696.5 nm, respectively; the bandwidth of the narrowband filter 103 is 1 nm to 15 nm, and the cutoff band of the narrowband filter 103 is 200 nm to 1200 nm. This allows the characteristic wavelengths of the desired observed objects Zr (zirconium), He (helium), and Ar (argon) within the jet to pass through, while blocking other wavelengths within the jet. As an example, relevant information about the narrowband filter 103 is shown in Table 1 below.

[0075] Table 1

[0076] Accordingly, in some embodiments, a plasma jet diagnostic method is provided, which is applied to the aforementioned plasma jet diagnostic device 1, and the method includes: Wavelength separation of components in the jet is achieved by using narrowband filters 103 of different wavelengths for plasma spraying physical vapor deposition, i.e., PS-PVD. The light intensity is adjusted when imaging each component by combining the light intensity adjustment element 102 and the exposure time 171 in the camera unit; for example, the light intensity is adjusted when imaging each component by combining the neutral density filter, the aperture 106 and the exposure time 171 in the CCD camera 107. The automatic analysis module 181 in the computer unit 108 analyzes the grayscale values ​​of the imaging image to characterize the energy field distribution characteristics of the plasma jet and the gas phase concentration field distribution characteristics of the deposited material in the jet.

[0077] It should be understood that all the features and advantages described above for the "plasma jet diagnostic device" also apply to this "plasma jet diagnostic method," and will not be repeated here.

[0078] This embodiment uses attenuators and narrowband filters to comprehensively control the optical path, enabling imaging of different plasma gas ionization flow fields and material fields of different materials. By utilizing the plasma ionization components and the emission spectra of evaporated and molten materials, it achieves calibration and imaging of individual components, and realizes the analysis of the energy field distribution characteristics of the plasma jet, the gas phase concentration field distribution characteristics of the deposited material in the jet, and the regularity of the above characteristics and changing trends at different locations. This device and method have the advantages of simple structure and direct and rapid extraction of information within the field of view, and can be used for process optimization and rapid diagnosis of processing quality.

[0079] In some embodiments, the combined attenuation rate of the exposure combination in the neutral density filter, aperture 106, and CCD camera 107 is adapted to keep the gray value of the plasma jet within a preset range under each operating condition.

[0080] In this embodiment, the combined attenuation rate of the neutral density filter, aperture 106, and exposure time 171 in the CCD camera 107 should ensure that the gray value of the jet under each operating condition is within a reasonable range, that is, the data of the jet gray value 255 under the operating condition with the highest light intensity accounts for a small portion, so as to facilitate the completion of axial and radial intensity analysis.

[0081] In some embodiments, the automatic analysis module 181 in the computer unit 108 uses grayscale values ​​for analysis based on the principle that the electrical signal is multiplied by the conversion coefficient (i.e., gain) through an analog-to-digital converter and then converted into a grayscale signal. That is, there is a mathematical relationship between the grayscale value and the overall amplitude and brightness, and the analysis is performed based on the mathematical relationship between the grayscale value and the overall amplitude and brightness.

[0082] The automatic analysis module 181 should be able to measure and calculate grayscale values ​​and obtain the characteristics and trends of different locations.

[0083] Accordingly, refer to Figure 4 In some embodiments, a plasma spray physical vapor deposition apparatus is provided, which includes the aforementioned plasma jet diagnostic device 1.

[0084] It should be understood that all the features and advantages described above for the "plasma jet diagnostic device" also apply to this "plasma spraying physical vapor deposition equipment", and will not be repeated here.

[0085] In this embodiment, the PS-PVD device may include a device body and the plasma jet diagnostic device 1 provided in this application embodiment, wherein the device body may be a known device in the related art. As an example, such as Figure 4 As shown, the main body of the equipment includes a spray gun 2, a six-axis robotic arm 3, a vacuum tank 4, a vacuum pump 5, a powder feeder 6, a protective gas source 7, a water chiller 8, a power distribution cabinet 9, an industrial computer 10, and a control system 11. The spray gun 2 can spray plasma jets and can be connected to the six-axis robotic arm 3. The spray gun 2 can also be connected to the powder feeder 6 and the protective gas source 7. The specific connection methods and structures of the spray gun 2, six-axis robotic arm 3, vacuum tank 4, vacuum pump 5, powder feeder 6, protective gas source 7, water chiller 8, power distribution cabinet 9, industrial computer 10, and control system 11 in the main body of the equipment can refer to relevant technologies and are not limited thereto.

[0086] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0087] To enable those skilled in the art to better understand the technical solution of the present invention, specific embodiments 1 to 7 are included below to further illustrate the present invention.

[0088] A plasma jet diagnostic method, using the plasma jet diagnostic device provided in this application, includes the following steps: Step 1: Perform actual distance calibration and set up camera 107 so that the lateral field of view of CCD camera 107 includes the jet section from 900mm to 1300mm along the jet axis, and keep the spray gun axis aligned with the lateral center line of CCD camera 107.

[0089] Step 2: After the jet is ejected, connect the power supply to the CCD camera 107, adjust the aperture 106, set the exposure time 171 in the camera control module 182 in the computer unit 108, and adjust the appropriate resolution 172 and frame rate 173 to complete the shooting preparation.

[0090] Step 3: After the jet stabilizes, insert the 587.5 nm narrowband filter 103, and take and save the image. The image obtained at this time is the He image under this working condition when no powder is fed.

[0091] Step 4: Replace the narrowband filter 103 with a 696.5 nm narrowband filter 103, and take and save the image. The image obtained at this time is the Ar image under this working condition when no powder is fed.

[0092] Step 5: Powder is fed in, and the jet is stabilized. The image is then captured and saved. The image obtained at this time is an Ar image during powder feeding under this condition.

[0093] Step 6: Replace the narrowband filter 103 with a 587.5 nm narrowband filter 103, and take and save the image. The image obtained at this time is the He image during powder feeding under this working condition.

[0094] Step 7: Replace the narrowband filter 103 with a 384 nm narrowband filter 103, and take and save the image. The image obtained at this time is the Zr image during powder feeding under this working condition.

[0095] Step 8: Adjust the operating conditions and repeat steps 3 through 7.

[0096] Step nine: Import all the obtained images into the automatic analysis module 181 of the computer unit 108 to analyze the gray values, the distribution characteristics of the plasma jet energy field, the distribution characteristics of the gas phase concentration field of the deposited material in the jet, and obtain the laws of the characteristics and trends of different positions.

[0097] The following specific embodiments further illustrate the technical solution of the present invention.

[0098] Example 1 In this embodiment, to analyze the distribution of Ar gas in the jet separately, a narrowband filter 103 with a center wavelength of 696.5 nm and a bandwidth of 10 nm was installed in front of the lens 105 of the high-speed camera 107. This band corresponds to a characteristic emission line of Ar atoms. Images of Ar in the plasma jet before and after powder feeding were captured. In this way, spectral interference from other components in the plasma was successfully filtered out, obtaining a clear image reflecting only the concentration distribution of the Ar component, providing reference data for subsequent accurate calculations of parameters such as the Ar jet width.

[0099] Similarly, by replacing the corresponding He (e.g., 587.5 nm) or Zr (e.g., 384 nm) filters, individual imaging and analysis of different components can be achieved.

[0100] Example 2 In this embodiment, imaging experiments were conducted under both maximum and minimum energy operating conditions.

[0101] This embodiment achieves the goal of ensuring that the image grayscale is evenly distributed within the dynamic range of 0 to 255 under different working conditions by replacing neutral density filters with different transmittance (1% to 20%) and adjusting aperture 106 and exposure time 171. This avoids saturation while preserving detail information, thereby supporting reliable analysis of axial and radial intensity distribution.

[0102] In specific applications, as shown in Table 1 above or Figure 2 As shown, the aperture was set to f / 8, the neutral density filter to 20% transmittance, the exposure time to 171 (range 150 µs), the resolution to 1920×1080, and the frame rate to 1000 fps. By adjusting these parameters, the image was able to completely cover the main deposition area, and the luminescence intensity of each gaseous component (such as Ar, He, and Zr) fell within the grayscale value range of 0-255, without exceeding the maximum value of 255. This allows for a visually intuitive presentation of the relative intensity distribution of each gaseous component without loss of information.

[0103] Example 3 In this embodiment, a coating deposition location area (900–1300 mm from the nozzle) is selected, and the image intensity value at this location is acquired using a CCD camera 107. The grayscale of the corresponding pixels in the image is then quantitatively extracted. Simultaneously, an OES (Optical Image Sensor) is used to acquire the plasma spectral signal at the same spatial location. The grayscale values ​​of the CCD image and the spectral line intensities obtained from the OES are compared as follows: Figures 5-8 As shown, through Figures 5 to 8 Comparative analysis revealed that the trends of change for both remained consistent across different locations.

[0104] The results indicate that CCD camera 107 imaging can replace the traditional OES method for online diagnosis of sedimentary jets and characterize the overall flow field meteorological features.

[0105] Example 4 In this embodiment, narrowband filters 103 of different diameters are selected and all are installed within the custom filter ring 101. For example, narrowband filters 103 with a diameter less than 50 mm and narrowband filters 103 with a diameter greater than or equal to 50 mm are selected.

[0106] Experimental comparisons revealed that when the diameter of the narrowband filter 103 is less than 50 mm, the edge of the filter ring 101 will block part of the jet imaging area, resulting in dark corners at the image edges; while when the diameter of the narrowband filter 103 is not less than 50 mm, the imaging area completely covers the 400 mm lateral field of view, ensuring diagnostic accuracy.

[0107] Example 5 In this embodiment, neutral density filters with transmittance of 1%, 5%, 10%, 15%, and 20% are used to image the jet under the same working conditions.

[0108] The results showed that when the transmittance was 20%, the light intensity was too high, resulting in too many gray-scale saturation points in the image; when the transmittance was less than 1%, the overall image was too dark, and details could not be distinguished. Finally, a transmittance range of 1% to 20% was selected to meet the light intensity control requirements under different working conditions.

[0109] Example 6 In this embodiment, the narrowband filter 103 is installed in the filter ring 101 at 0°, 5° and 10° respectively to capture the jet under the same working condition.

[0110] The results show that 0° installation ensures that the center wavelength of the filter is consistent with the design; when tilted by 5° to 10°, the filter can still work, the center wavelength shift is less than 0.5 nm, and the imaging quality is basically unaffected.

[0111] Example 7 In this embodiment, a combination of lens 105 and CCD camera 107 is used, with a horizontal field of view of 400 mm and a vertical field of view of 200 mm, which can cover the deposition section jet in the 900~1300 mm area of ​​the nozzle.

[0112] The results show that if the lateral field of view is less than 400 mm, the outer diffusion zone of the jet cannot be covered; if the longitudinal field of view is less than 200 mm, not enough pixels can be obtained for radial analysis. Therefore, the imaging system should have a lateral field of view ≥ 400 mm and a longitudinal field of view ≥ 200 mm.

[0113] The parts of this invention not described in detail are techniques known to those skilled in the art.

[0114] The basic principles of the present invention have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in the present invention are merely examples and not limitations, and should not be considered as essential features of each embodiment of the present invention. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the present invention to the necessity of employing the aforementioned specific details.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plasma jet diagnostic device for use in plasma spraying physical vapor deposition equipment, characterized in that, The plasma jet diagnostic device includes: an optical path unit, a camera unit, and a computer unit; The optical path unit includes an intensity adjustment component and a narrowband filter, the camera unit includes a lens and a camera, and the camera is electrically connected to the computer unit. Along a direction perpendicular to the side of the plasma jet and gradually away from the plasma jet, the light intensity adjustment device, the narrowband filter, the lens, and the camera are arranged in sequence. The light intensity adjustment device is used to adjust the light intensity, and the narrowband filter is used to acquire wavelength light of a preset band. The image to be tested is obtained through the lens and the camera, and the image in the camera is analyzed by the computer unit.

2. The plasma jet diagnostic device according to claim 1, characterized in that, The optical path unit also includes a filter ring, and the light intensity adjustment component and the narrowband filter are both installed inside the filter ring.

3. The plasma jet diagnostic device according to claim 2, characterized in that, The light intensity adjustment component is vertically installed inside the filter ring; And / or, the narrowband filter is mounted vertically or obliquely within the filter ring; And / or, the light intensity adjustment element includes a neutral density filter, the attenuation rate of which is adjusted within the range of 1% to 20%.

4. The plasma jet diagnostic device according to claim 2, characterized in that, The filter ring is connected to the lens via an adapter ring; And / or, the filter ring is threadedly connected to the lens; And / or, the filter ring is provided with at least two mounting slots for mounting the light intensity adjustment component and the narrowband filter; And / or, the light intensity adjustment element and the narrowband filter are respectively threadedly connected to the filter ring.

5. The plasma jet diagnostic device according to claim 1, characterized in that, The size of the light intensity adjustment component is ≥50mm; And / or, the size of the narrowband filter is ≥50mm.

6. The plasma jet diagnostic device according to claim 1, characterized in that, The focusing distance of the lens is ≥1500mm; And / or, the field of view of the lens is 22 degrees 50 minutes to 5 degrees 20 minutes, or the minimum field of view of the lens is less than 5 degrees 20 minutes; And / or, the camera unit further includes an aperture, and the lens is connected to the aperture.

7. The plasma jet diagnostic device according to any one of claims 1 to 6, characterized in that, The camera includes a CCD camera; And / or, the camera is adapted to operate at a temperature of ≥40°C; And / or, the side axis of the camera is mounted perpendicular to the plasma jet axis and kept horizontal and fixed; And / or, the maximum lateral field of view of the camera unit including the lens and the camera is ≥400mm and the maximum longitudinal field of view is ≥200mm; And / or, the narrowband filter includes at least three narrowband filters, the center wavelengths of the at least three narrowband filters being 384nm, 587.5nm, and 696.5nm, respectively; the bandwidth of the narrowband filter is 1nm to 15nm, and the cutoff band of the narrowband filter is 200nm to 1200nm.

8. A plasma jet diagnostic method, characterized in that, The method, applied to the plasma jet diagnostic apparatus according to any one of claims 1 to 7, comprises: Wavelength separation of components within the jet during plasma spraying physical vapor deposition is achieved using narrowband filters of different wavelengths. The light intensity of each component can be adjusted during imaging by combining the light intensity adjustment device and the exposure time in the camera unit; The automatic analysis module in the computer unit analyzes the grayscale values ​​of the imaging images to characterize the energy field distribution characteristics of the plasma jet and the gas phase concentration field distribution characteristics of the deposited material in the jet.

9. The plasma jet diagnostic method according to claim 8, characterized in that, The light intensity adjustment device includes a neutral density filter, the camera unit includes an aperture connected to the lens, and the camera includes a CCD camera; the combined attenuation rate of the exposure combination in the neutral density filter, the aperture, and the CCD camera is adapted to ensure that the gray value of the plasma jet is within a preset range under each operating condition. And / or, the automatic analysis module in the computer unit performs analysis using grayscale values, including: multiplying the electrical signal by a conversion coefficient using an analog-to-digital converter to convert it into a grayscale signal, and performing analysis based on the mathematical relationship between the grayscale value and the overall amplitude and brightness.

10. A plasma spraying physical vapor deposition apparatus, characterized in that, The plasma jet diagnostic device includes any one of claims 1 to 7.

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