A process for coating transparent parts of hatch covers

Abstract

The present invention discloses a process method for coating a hatch cover transparent part, which belongs to the field of coating technology and includes the following steps: S1, applying a primer to the hatch cover transparent part, firstly preparing the primer, then applying the primer, then waiting for the surface to dry, and finally drying the hatch cover transparent part; S2, placing the hatch cover transparent part on a supporting part, then sending the hatch cover transparent part and the bottom coating part into a tank body, a manipulator is provided inside the tank body for coating the surface of the hatch cover transparent part, closing the sealed tank body, and evacuating; S3, introducing oxygen and argon into the tank body, while ensuring that the argon-oxygen ratio is within the range of 30-40 during the coating process; S4, applying a top coating to the hatch cover transparent part. After coating the hatch cover transparent part by the process method, the light transmittance and square resistance of the hatch cover transparent part can meet the use requirements, that is, the light transmittance is ≥80%, and the square resistance is within the range of 9-12Ω / □.

Description

Technical Field

[0001] The invention belongs to the technical field of coating, and in particular relates to a process method for coating a transparent part of a hatch cover. Background Art

[0002] The integrated canopy transparent part eliminates the interface between the traditional fixed windshield and the movable canopy, integrating the separate windshield and canopy into a whole. It is a large-sized hyperbolic special-shaped organic transparent part.

[0003] The large integrated stealth canopy represents the most advanced fighter canopy structure and the highest level of transparent parts technology in the world. The stealth technology of transparent parts of the canopy is essentially to reduce the reflection of radar signals in this part of the aircraft and prevent radar rays from entering the cockpit. The organic stealth coating technology used in the integrated canopy is a high-tech technology involving a variety of disciplines such as materials science, optics, electromagnetism, mechatronics and information technology.

[0004] With the rapid development of anti-stealth technology, in order to further improve the comprehensive combat effectiveness of fighter jets, the new generation of fighter jets have higher and higher requirements for reducing the radar cross section (RCS). To meet the requirements of the stealth indicators of my country's new generation of fighter jets at this stage, it is necessary to reduce the cockpit cover RCS to a very low level, which puts high demands on the cockpit RCS reduction plan and technology.

[0005] The key indicators of cockpit stealth are to plate a composite stealth film system on the surface of the integrated cockpit cover transparent part, shield the cockpit cavity, and reduce cockpit scattering. To achieve the best stealth performance, the film system needs to have the lowest surface resistance, and the thicker the functional metal layer, the better. However, if the metal functional layer is too thick, the light transmittance of the film system will be reduced. How to balance the electromagnetic performance and optical performance of the integrated cockpit cover transparent part is a current technical difficulty in China. Summary of the invention

[0006] In view of the above problems in the prior art, an object of the present invention is to provide a process for coating a transparent part of a hatch cover.

[0007] The present invention provides the following technical solutions:

[0008] A process for coating a transparent part of a hatch cover, comprising the following steps:

[0009] S1, applying primer to the transparent parts of the hatch cover, firstly, the primer is prepared, then it is sprayed, then it is left to stand and wait for the surface to dry, and finally it is dried;

[0010] S2, placing the hatch cover transparent part on the supporting part, and then sending the hatch cover transparent part and the bottom coating part into the tank body. A manipulator is provided inside the tank body for coating the surface of the hatch cover transparent part, closing the sealed tank body, and evacuating the vacuum;

[0011] S3, introducing oxygen and argon into the tank body, while ensuring that the argon-oxygen ratio is within the range of 30-40 during the coating process;

[0012] S4, the transparent parts of the hatch cover are top-coated. First, the top coating is prepared, then it is spray-coated, and then it is left to stand still and wait for the surface to dry, and finally it is dried.

[0013] Specifically, a target material of Φ150 mm, a target spacing of 68 mm, a speed of 20 mm / s, and a target-substrate distance of 81 mm were selected.

[0014] Specifically, indium zinc oxide is selected as the film layer material.

[0015] Specifically, the supporting component includes a frame body, a bracket installed on the frame body, and the workpiece is placed on the bracket.

[0016] Specifically, the bottom coating component includes a transverse moving component, a mounting plate installed on the transverse moving component, the transverse moving component is used to drive the mounting plate to move along the X-axis, a gear is movably installed on the mounting plate, a mounting frame is installed on the mounting plate, a motor 1 is driven by a gear meshing transmission, the motor 1 is used to drive the mounting frame to rotate around the Z-axis, and the mounting seat is movably installed on the mounting frame through the motor 2 and the electric cylinder, the motor 2 is used to drive the mounting seat to rotate around the X-axis, and the electric cylinder is used to drive the mounting seat to move along the Z-axis; a positioning frame installed on the mounting seat, a rotating frame movably installed on the positioning frame through the motor 3, the motor 3 is used to drive the rotating frame to rotate around the X-axis, a motor 4 is installed on the rotating frame, the main gear on the motor 4 is connected to the driven gear through a chain, the driven gear is movably installed on the rotating frame, the target material is installed on the driven gear through the connecting seat, and the motor 4 is used to drive the target material to rotate around the Y-axis.

[0017] The beneficial effects of the present invention are:

[0018] After coating the hatch cover transparent part by the process method, the light transmittance and square resistance of the hatch cover transparent part can meet the use requirements and achieve the best possible stealth performance, that is, the light transmittance is ≥80% and the square resistance is in the range of 9 to 12Ω / □. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 is a three-dimensional diagram of the support component and the bottom coating component in the present invention;

[0021] Figure 2 It is a schematic structural diagram of the bottom coating component in the present invention;

[0022] The markings in the figure are: 1. frame; 2. bracket; 3. horizontal moving part; 4. target material; 5. mounting plate; 6. gear; 7. motor one; 8. mounting frame; 9. electric cylinder; 10. motor two; 11. mounting seat; 12. positioning frame; 13. motor three; 14. rotating frame; 15. motor four; 16. driven gear; 17. connecting seat. DETAILED DESCRIPTION

[0023] Since the composite stealth film system is plated on the surface of the integrated cockpit cover transparent part, shielding the cockpit cavity and reducing cockpit scattering are key indicators of cockpit stealth. The electromagnetic performance of the film system can be evaluated by the vertical reflectivity index. The relationship between the vertical reflectivity and the surface resistance of the film layer is:

[0024]

[0025] Where: ——vertical reflectivity; ——Vacuum wave impedance (constant 377Ω); ——Surface resistance.

[0026] To achieve the best stealth performance, the film system needs to have the lowest surface resistance and the thicker the functional metal layer, the better. However, if the metal functional layer is too thick, the film system's light transmittance will be reduced. How to balance the electromagnetic and optical properties of the integrated canopy transparent parts is currently a technical difficulty in China.

[0027] The film system can achieve the lowest possible surface resistance from three aspects:

[0028] 1: Choose a film material with better conductivity. Under the same transmittance, the IZO (indium zinc oxide) material we choose has better conductivity than the traditional ITO (indium tin oxide).

[0029] 2: While ensuring the transmittance requirement, the thicker the film layer, the lower the resistance.

[0030] 3: By controlling the ratio of oxygen to argon in the vacuum chamber during coating, the resistance value can be minimized.

[0031] The table below shows the results of transmittance and square resistance after testing with different argon-oxygen ratios.

[0032]

[0033] Ar is argon, O2 is oxygen, and P is the target power. Compared with targets with small diameters, targets with diameters of Φ150mm have a larger sputtering area and increase the sputtering rate. At the same time, compared with targets with large diameters, targets have better flexibility and controllability, and improve the uniformity of film thickness in the coating of large-sized hyperbolic and shaped transparent parts. The target-substrate distance of about 80mm can also appropriately increase the deposition rate and uniformity of the film, and obtain a relatively uniform film thickness. In order to prevent uneven deposition of target atoms around the target and the appearance of rainbow stripes, a target spacing of 68mm is used.

[0034] For the selected speed value, a speed that is too small will result in the film layer being too thick, the coating temperature being too high, the adhesion being low, and the film cracking or peeling off. A speed that is too large will result in insufficient target atom deposition and a large surface resistance of the film layer. A speed of 20 mm / s is more appropriate. Finally, the coating path is set along the inner surface of the large-sized hyperbolic special-shaped transparent part, which can effectively and comprehensively coat a film system with controllable film thickness.

[0035] The transparent parts of the aircraft canopy are the main field of vision and radiation area for pilots, which greatly affects the pilot's flight safety. In order to provide the pilot with the most realistic and safe field of vision, the transparent parts need to have high light transmittance and good electromagnetic shielding performance. However, while improving the light transmittance, the square resistance of the film layer will also increase, which will reduce the electromagnetic shielding performance. Therefore, how to balance the electromagnetic performance and optical performance of the film layer of the canopy transparent parts has become a major difficulty.

[0036] Since light transmittance directly affects the clarity and reality of the pilot's vision, its value cannot be too low. The original transparent sheet has a light transmittance of about 90%. After forming, CNC, polishing and other operations, after the film is plated, it should be kept above 80%. At this time, the transparent part of the cockpit cover can ensure a clear view of the flight to a large extent.

[0037] Electromagnetic shielding effectiveness is an important parameter to measure the ability of materials or structures to shield electromagnetic waves. Its function is to cut off the propagation path of electromagnetic waves, thereby eliminating interference. Plating a shielding film layer on the transparent part of the cockpit cover can effectively reduce the propagation of electromagnetic waves, providing safer flight conditions for pilots and other equipment inside the cockpit. The lower the square resistance of the transparent film layer, the better its electromagnetic shielding effectiveness. However, since it is necessary to ensure that the transparent part has good light transmittance (≥80%), good electromagnetic shielding effectiveness can be obtained when the square resistance value is 9~12Ω / □ (shielding effectiveness ≥21dB at 1~4GHz, shielding effectiveness ≥22dB at 4~18GHz).

[0038] Therefore, after the test, when the argon-oxygen ratio is in the range of 30~40, it can ensure that the transmittance and square resistance of the coated rear hatch transparent parts meet the use requirements.

[0039] The present invention provides a process for coating a transparent part of a hatch cover, comprising the following steps:

[0040] Step 1: Prime the transparent parts of the hatch cover. First, mix the primer, then apply it, then wait for the surface to dry, and finally dry it.

[0041] Specifically, primer coating is divided into three steps: batching, spray coating and drying; batching is completed in the batching room, the temperature of the batching room is (17-26)°C, and the relative air humidity is (20-50)%; the raw materials are poured into the beaker in turn and mixed, and stirred at medium speed for 30 minutes using a magnetic stirrer, and filtered with a filter device to remove bubbles and impurities. The coating must be used within 2 hours after preparation, and re-prepared after 2 hours; spray coating is to install the hatch cover transparent parts on the spray coating rack, rotate the spray coating rack to make the product vertical, connect the spray coating gun to the paint container, and the spray coating personnel hold the spray coating gun and spray evenly along the upper edge of the contour line of the hatch cover transparent parts. After spray coating, it is allowed to stand for 1 hour in an environment with a temperature of (17-26)°C and a relative air humidity of (20-50)%. Finally, the aircraft cockpit cover transparent parts are pushed into an oven at 60°C for curing for 6 hours.

[0042] Step 2: Place the hatch cover transparent part on the supporting part, and then send the hatch cover transparent part and the bottom coating part into the tank body, i.e., the magnetron sputtering coating machine. The bottom coating part provides the target material to coat the surface of the hatch cover transparent part, and then close the sealed tank body.

[0043] Step three, introduce oxygen and argon into the tank body, and at the same time ensure that the argon-oxygen ratio during the coating process is in the range of 30~40, select a Φ150mm target material, a target spacing of 68mm, that is, an operation is performed every time the target moves 68mm, a target moving speed of 20mm / s, and a target-base distance of 81mm, that is, the distance between the target material and the transparent surface of the hatch cover to be plated.

[0044] Step 4: Topcoat the transparent parts of the hatch cover. First, mix the ingredients for the topcoat, then apply it by pouring, then wait for the surface to dry, and finally dry it.

[0045] Specifically, the top coating process is exactly the same as the primer process, including the three steps of batching, spray coating and drying.

[0046] like Figure 1 As shown, the supporting component includes a frame body 1 , a bracket 2 installed on the frame body 1 , and a workpiece is placed on the bracket 2 .

[0047] like Figure 2 As shown in the figure, X refers to the X-axis in the coordinate system, Y refers to the Y-axis in the coordinate system, and Z refers to the Z-axis in the coordinate system.

[0048] The bottom coating component includes a lateral moving component 3, a mounting plate 5 installed on the lateral moving component 3, the lateral moving component 3 is used to drive the mounting plate 5 to move along the X-axis, a gear 6 is movably installed on the mounting plate 5, a mounting frame 8 is installed on the mounting plate 5, a motor 7 is driven by meshing with the gear 6, and the motor 7 is used to drive the mounting frame 8 to rotate around the Z-axis. At the same time, the mounting seat 11 is movably installed on the mounting frame 8 through the motor 2 10 and the electric cylinder 9, the motor 2 10 is used to drive the mounting seat 11 to rotate around the X-axis, and the electric cylinder 9 is used to drive the mounting seat 11 to move along the Z-axis; a positioning frame 12 installed on the mounting seat 11, a rotating frame 14 movably installed on the positioning frame 12 through the motor 3 13, the motor 3 13 is used to drive the rotating frame 14 to rotate around the X-axis, a motor 4 15 installed on the rotating frame 14, the main gear on the motor 4 15 is connected to the driven gear 16 through a chain, the driven gear 16 is movably installed on the rotating frame 14, the target material 4 is installed on the driven gear 16 through the connecting seat 17, and the motor 4 15 is used to drive the target material 4 to rotate around the Y-axis.

[0049] The transverse moving component 3, motor 1 7, motor 2 10, electric cylinder 9, motor 3 13, motor 4 15 and target material 4 are communicatively coupled to a controller.

[0050] The controller is a programmable CNC system. As a central control system, the controller is used to realize the program input and operation control of the whole machine, and realize the full automation of the coating process. The control system can be used as a system that connects various actuators to move according to the logical trajectory, and the actuators are controlled by programming to run according to the required operation steps.

[0051] Different hatch cover transparent parts are designed with different paths, speeds and target holding trajectories. Therefore, the bottom surface coating parts undergo different work processes through different input trajectories.

[0052] Specifically, the working principle of the bottom surface coating component:

[0053] The lateral moving component 3 is used to control the movement of the target material 4 along the length direction of the central axis of the transparent part of the hatch cover, the motor 1 7 is used to control the rotation of the target material 4 around the Z axis, the motor 2 10 and the motor 3 13 are used to control the rotation of the target material 4 around the X axis, the electric cylinder 9 is used to control the movement of the target material 4 along the Z axis, and the motor 4 15 is used to control the rotation of the target material 4 around the Y axis.

[0054] After coating the hatch cover transparent part by the process method, the light transmittance and square resistance of the hatch cover transparent part can meet the use requirements and achieve the best possible stealth performance, that is, the light transmittance is ≥80% and the square resistance is in the range of 9 to 12Ω / □.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A process for coating a transparent part of a hatch cover, characterized in that: The following steps are involved: S1, applying primer to the transparent parts of the hatch cover, firstly, the primer is prepared, then it is sprayed, then it is left to stand and wait for the surface to dry, and finally it is dried; S2, placing the hatch cover transparent part on the supporting part, then sending the hatch cover transparent part and the bottom coating part into the tank body, the bottom coating part provides a target material to coat the surface of the hatch cover transparent part, indium zinc oxide is selected as the film material, and the sealed tank body is closed and vacuumed; The bottom coating component includes a transverse moving component, a mounting plate installed on the transverse moving component, the transverse moving component is used to drive the mounting plate to move along the X-axis, the gear is movably installed on the mounting plate, the mounting frame is installed on the mounting plate, the motor one is driven by the gear meshing with the gear, the motor one is used to drive the mounting frame to rotate around the Z-axis, and the mounting seat is movably installed on the mounting frame through the motor two and the electric cylinder, the motor two is used to drive the mounting seat to rotate around the X-axis, and the electric cylinder is used to drive the mounting seat to move along the Z-axis; a positioning frame installed on the mounting seat, a rotating frame movably installed on the positioning frame through the motor three, the motor three is used to drive the rotating frame to rotate around the X-axis, and the motor four is installed on the rotating frame. The main gear on the motor four is connected to the driven gear through a chain, the driven gear is movably installed on the rotating frame, the target material is installed on the driven gear through the connecting seat, and the motor four is used to drive the target material to rotate around the Y-axis; S3, introducing oxygen and argon into the tank body, while ensuring that the argon-oxygen ratio is within the range of 30-40 during the coating process; S4, the transparent parts of the hatch cover are top-coated. First, the top coating is prepared, then it is spray-coated, and then it is left to stand still and wait for the surface to dry, and finally it is dried.

2. A process for coating a transparent part of a hatch cover according to claim 1, characterized in that: A target of Φ150mm is selected.

3. The process for coating a transparent part of a hatch cover according to claim 1, characterized in that: A target spacing of 68 mm was selected.

4. The process for coating a transparent part of a hatch cover according to claim 1, characterized in that: A target moving speed of 20 mm / s was selected.

5. The process for coating a transparent part of a hatch cover according to claim 1, characterized in that: A target-substrate distance of 81 mm was selected.

6. The process for coating a transparent part of a hatch cover according to claim 1, characterized in that: The supporting component comprises a frame body, a bracket installed on the frame body, and a workpiece is placed on the bracket.

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