A coupling monitoring system and forming control method for a carbon fiber microwave reflector

Abstract

The application provides a coupling monitoring system and forming control method for a carbon fiber microwave reflector surface, a sensor lead is connected to a monitoring point on the microwave reflector surface, the sensor lead is connected to the microwave reflector surface through a hot press tank, an optical fiber grating sensor demodulator converts an optical fiber grating sensor signal into a digital signal and transmits the digital signal to a data acquisition processor for acquisition and processing; through the change of process parameters in the forming process of the microwave reflector surface, the coupling deformation data of the reflector surface is collected, and the process control parameters for ensuring the accuracy of the formed surface of the reflector surface are analyzed. The application realizes the deformation monitoring of the carbon fiber structure surface forming of the microwave reflector surface, optimizes the surface forming control parameters, effectively guarantees the surface accuracy and quality of the reflector surface forming, realizes that the root mean square accuracy of the surface accuracy of the reflector surface reaches 0.04mm, meets the reflection use of the microwave below the Ku frequency band, can be monitored throughout, and solves the influence of the concentrated stress caused by the uneven structure on the surface accuracy of the reflector surface.

Description

Technical Field

[0001] This invention relates to the fields of microwave detection, radio communication, and electronic interference, and in particular to a method for controlling the high-precision surface of a carbon fiber composite microwave reflector by monitoring and analyzing the molding process during its development. This invention is especially applicable to the precision control of non-developable high-precision complex surfaces formed from carbon fiber plain weave fabrics, and can be extended to the design and manufacturing of microwave reflectors for lightweight, high-precision, and corrosion-resistant applications. Background Technology

[0002] With the widespread application of composite materials, especially the increasing use of carbon fiber composite reflectors in microwave antennas, the shapes of reflector supports are becoming increasingly complex, and the precision requirements for reflector surface profiles are becoming increasingly stringent. Furthermore, due to their low density and high modulus, carbon fiber composite microwave reflectors allow for integrated structural and functional design and manufacturing, leading to their faster adoption in modern microwave equipment that demands lightweight and corrosion resistance. However, the molding process for composite reflectors is complex, involving stress-coupled deformation. Currently, there is no way to monitor stress and strain throughout the entire process, making it difficult to control variations during molding, often resulting in difficulty in controlling surface precision and ensuring molding quality. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, this invention provides a coupling monitoring system and molding control method for carbon fiber microwave reflective surfaces. The purpose of this invention is to solve the problem of difficult molding accuracy control of carbon fiber composite reflective surfaces, providing a convenient and effective monitoring method that enables high-precision surface control. This method is suitable for controlling the surface accuracy of carbon fiber composite reflective surfaces during autoclave curing, thereby realizing the manufacturing of carbon fiber composite microwave reflective surfaces. Through this molding monitoring method, combined with process deformation data analysis, the molding control parameters of the reflective surface can be effectively optimized, ensuring the molding accuracy and quality of the reflective surface.

[0004] The technical solution adopted by this invention to solve its technical problem is:

[0005] A carbon fiber microwave reflector, such as Figure 2As shown, the structure includes a metallized reflective layer and a support body, and is a thin-walled parabolic rotation structure. The metallized reflective layer is the inner layer of the concave surface of the parabola. A carbon fiber microwave reflective surface is made of sprayed aluminum. The support body is formed by bonding a carbon fiber inner skin, an outer skin, an aluminum honeycomb, a flanged flange, and a mounting bracket using a structural carrier adhesive film (J-95). The inner and outer skins are located on the inner and outer surfaces of the aluminum honeycomb, forming a concave parabolic surface. The outer edge of the parabola is a flanged flange, and the mounting bracket is located on the outer surface of the parabola. The height of the support from the bottom of the parabola is one-third of the total height of the parabola; both the inner and outer skins are made of four layers of carbon fiber prepreg; the flanged edge is filled with foamed aluminum honeycomb at the outer edge of the parabola; the installation and positioning support is a metal insert with titanium at its center, which is embedded in the aluminum honeycomb, and short fiber reinforced bulk molding compound is used to fill the area around the junction of the insert and the aluminum honeycomb. The short fiber reinforced bulk molding compound is 30 mm long alkali-free glass fiber, and the epoxy resin accounts for 80% of the weight and the glass fiber accounts for 20% of the weight.

[0006] This invention also provides a coupling monitoring system for carbon fiber microwave reflective surfaces, such as... Figure 1 The diagram shows a device for detecting and recording strain at various points during the molding of a microwave reflective surface. It includes a fiber optic grating sensor, a fiber optic cable through-wall pressure-resistant sealing device, a fiber optic grating sensor demodulator, and a data acquisition processor (computer). The data acquisition processor (computer) is connected to the fiber optic cable through-wall pressure-resistant sealing device via the fiber optic grating sensor demodulator. Sensor leads are extended from the fiber optic cable through-wall pressure-resistant sealing device and connected to monitoring points on the microwave reflective surface. The fiber optic grating sensor is adhered to the first layer of carbon fiber prepreg on the inner skin of the microwave reflective surface. The microwave reflective surface is placed in the working... On the loading platform, the microwave reflector, fiber Bragg grating sensor, and tooling carriage are all located inside the autoclave. The sensor lead passes through the autoclave and connects to the microwave reflector. A pressure-resistant sealing device through the wall of the optical cable leads the fiber Bragg grating sensor signal out of the autoclave via the sensor lead. The fiber Bragg grating sensor demodulator converts the signal into digital data, which is then transmitted to a data acquisition processor (computer) for processing. By analyzing the changes in process parameters during the microwave reflector forming process, coupling deformation data of the reflector is collected, and the process control parameters that ensure the accuracy of the reflector's formed surface are determined. The optical fiber is protected by a pressure-resistant sealing device through the pre-drilled thermocouple wire holes in the autoclave body. Figure 3 As shown, the armored cable on the left extends out of the can and needs to withstand pressure. Figure 3 The optical fiber is located inside the stainless steel tank. The fiber optic grating sensor is independently led out of the tank for monitoring and is encapsulated with a heat-resistant polyimide protective film. The microwave reflective surface is formed by arc-spraying aluminum to create a metal powder accumulation layer of equal thickness, which is then bonded to the carbon fiber composite skin using a structural adhesive film.

[0007] The fiber Bragg grating sensor is a fiber Bragg grating string with an operating temperature of -40~200℃, a grating spacing of 130±1mm, polyimide fiber, a femtosecond point-by-point grating, a grating length of 5±1mm, reflectivity ≥50%, bandwidth ≤0.4nm, sealing pressure resistance ≥1.3Mpa, and an FC / APC fiber connector. It does not affect the reflective surface formation and allows for continuous monitoring, providing comprehensive data. The fiber Bragg grating sensor is uniformly distributed on the inner side of the parabolic surface of the microwave reflector, consisting of six longitudinal (busbar) lines and one circumferential line. The six longitudinal lines are distributed as follows... Figure 4 As shown, the six longitudinal lines are all located on the generatrix inside the parabola of the microwave reflector, and each pair of them forms a 60-degree angle with the center of the parabola. Each monitoring channel is formed by two longitudinally distributed fiber optic grating sensors spaced 180 degrees apart, arranged in a circumferential pattern as shown. Figure 5 As shown, a parabolic edge evenly distributed around the inner side of the microwave reflector surface is formed.

[0008] The fiber Bragg grating sensor demodulator is an industrial-grade fanless Si155 demodulator with dynamic and static full-spectrum analysis capabilities, equipped with 4 channels and 160nm bandwidth, and is perfectly compatible with the HYPERION platform and ENLIGHT analysis software.

[0009] The optical cable through-wall pressure-resistant sealing device is made by sealing the optical fiber inside a stainless steel tube. The optical fiber is led out as armored optical cable at both ends of the stainless steel tube. The sealing pressure inside the stainless steel tube is greater than or equal to 1.3 MPa, the working temperature is -40~200℃, and the diameter of the stainless steel tube is 3 mm.

[0010] The inner and outer skins are made of plain weave fabric reinforced with epoxy resin prepreg in sheet roll form. The material consists of four layers of 0.1mm thick T800 carbon cloth, with the width achieved by splicing and the thickness by stacking the thickness of a single sheet.

[0011] The core material of the aluminum honeycomb is a regular hexagonal honeycomb with a density of 53 kg / m³. 3 Corrosion resistance means that after a 30-day salt spray test, the weight loss per unit area of ​​the exposed aluminum foil surface of the honeycomb core material is no more than 0.135 mg / cm2.

[0012] The structural carrier film is a sheet-like thin roll material reinforced with nylon mesh at room temperature, with a volatile matter content of less than 1% and a flowability of greater than 55%.

[0013] The spraying process of the microwave reflective surface is completed by aluminum wire arc spraying. First, a film-forming release agent is applied to the microwave reflective surface forming mold, then a polymer transfer film is sprayed, and then pure aluminum powder is arc sprayed on the outside of the polymer transfer film to form a uniform metal layer with a thickness greater than 0.25mm. Finally, it is bonded to the carbon fiber skin support body by structural adhesive film.

[0014] This invention also provides a molding control method for a coupling monitoring system of carbon fiber microwave reflective surfaces. The molding control of the microwave reflective surface is carried out in four steps superimposed sequentially in an autoclave. The molding control parameters are as follows:

[0015] Step 1: The molding control parameters are the bonding molding and curing parameters for the metallized reflective layer and the carbon fiber inner skin of the microwave reflective surface support: heating and cooling rate of 1℃, pressure of 0.4Mpa, and holding at 130℃ for 3 hours.

[0016] Step 2: The molding control parameters are the bonding and curing parameters of the aluminum honeycomb of the microwave reflective surface support and the inner skin: heating and cooling rate of 1℃, pressure of 0.15MPa, and heat preservation at 130℃ for 2.5 hours.

[0017] Step 3: The molding control parameters are the local foaming adhesive filling and curing parameters for the aluminum honeycomb core material of the microwave reflective surface support: heating and cooling rate of 1℃, pressure of 0.15MPa, and heat preservation at 130℃ for 2.5 hours.

[0018] Step 4: The molding control parameters are the bonding and curing parameters for the carbon fiber outer skin of the microwave reflective surface support: heating and cooling rate of 0.5℃, pressure of 0.2MPa, and holding at 130℃ for 3 hours;

[0019] Before use, the fiber optic grating sensor is calibrated at temperature (see 5(5)) to eliminate the thermal expansion effect caused by temperature. The support of the microwave reflective surface is cured in four stages, including curing the metallized reflective surface spraying and the carbon fiber inner skin of the support, curing the aluminum honeycomb and the inner skin, curing the aluminum honeycomb core material with local foaming glue filling, and curing the carbon fiber outer skin. The curing control parameters are different for each curing stage as the structure changes.

[0020] The mounting and positioning support is formed by two-stage adhesive bonding and room temperature curing. The metal insert at the center of the mounting and positioning support is made by impregnating fiberglass chopped strand mat with J-135 adhesive and curing it at room temperature for 24 hours under mechanical pressure, bonding it to the inner skin and aluminum honeycomb of the support body. Then, chopped glass fiber filaments are added to J-135 adhesive to form a clump molding compound, which is used to wrap around the metal insert of the mounting and positioning support and cured at room temperature. Finally, carbon fiber plain weave cloth and J-133 adhesive are laid down for reinforcement, vacuum sealed and cured at room temperature.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. This invention is applicable to the shape control of microwave reflector manufacturing. It realizes deformation monitoring of the carbon fiber structure shape forming of microwave reflectors. Through the analysis of monitoring data, the shape forming control parameters are optimized, effectively ensuring the shape accuracy and quality of the reflector. The root mean square accuracy of the reflector shape can reach 0.04mm, meeting the requirements for microwave reflection below the Ku band.

[0023] 2. This invention uses a fiber optic grating sensor to monitor the molding process, which is also applicable to thin-walled parts. It can be implanted in one go and can be monitored throughout the entire process.

[0024] 3. This invention uses a secondary adhesive bonding method for the four supports, which effectively solves the problem of stress concentration caused by structural imbalance affecting the surface accuracy of the reflector. Attached Figure Description

[0025] Figure 1 This is a schematic diagram for monitoring deformation during the curing and molding process in an autoclave.

[0026] Figure 2 This is a schematic diagram of the reflective surface structure.

[0027] Figure 3 This is a schematic diagram of a protective sleeve for a can.

[0028] Figure 4 This is a schematic diagram showing the arrangement of the sensor busbars.

[0029] Figure 5 Schematic diagram of sensor circumferential arrangement.

[0030] Among them, 1. Data acquisition processor (computer), 2-Fiber Bragg grating sensor demodulator, 3-Optical cable through-wall pressure-resistant sealing device, 4-Sensor lead wire, 5-Autoclave, 6-Microwave reflective surface, 7-Fiber Bragg grating sensor, 8-Tooling vehicle, 9-Metallized emitting layer, 10-Flanged flange, 11-Inner skin, 12-Outer skin, 13-Mounting and positioning bracket, 14-Aluminum honeycomb. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0032] This invention employs an embedded fiber optic grating sensor to monitor the deformation of a carbon fiber composite microwave reflector during the autoclave molding process, studying the deformation law of the reflector and achieving control over the surface precision of the microwave reflector manufacturing process. The reflector is an integral structure reinforced with a flange, comprising a continuous metallized reflector, a carbon fiber composite A-layer honeycomb structure support, and a support connecting it to a high-frequency generator. It also includes a method for grating-based deformation monitoring and a method for controlling the layup and molding of the carbon fiber composite A-layer structure.

[0033] The specific production process is as follows:

[0034] (1) The fiber is made of polyimide material and can work in an environment of 300℃; the fiber grating is made of femtosecond laser-etched grating.

[0035] (2) The sleeve is a capillary tube made of Teflon material.

[0036] (3) Armored optical cables should be selected for the external optical cable, with a diameter of about 3mm; FC / APC connectors should be used for the optical fiber connector.

[0037] (4) Tank wall sealing solutions

[0038] First, pass the optical cable through the stainless steel sheath. Fill the gap between the optical cable and the stainless steel sheath with a sealant that can withstand high temperatures of 150°C to prevent air leakage. The seal has a pressure resistance of ≥1.3 MPa.

[0039] (5) Calibration of the temperature effect of fiber Bragg grating sensor:

[0040] 5.1) Attach the fiber Bragg grating to the wall of the high and low temperature chamber and attach the thermocouple next to the fiber Bragg grating.

[0041] 5.2) Set the high and low temperatures, starting from room temperature. The temperature should begin at 30 degrees Celsius, increasing by 10 degrees Celsius each time, with a cycle of 10 minutes of heating followed by 10 minutes of holding. Continue heating until the temperature reaches 120 degrees Celsius.

[0042] 5.3) The thermocouple temperature is analyzed by a temperature monitoring instrument, and the fiber optic demodulator is analyzed by a fiber optic grating wavelength strain.

[0043] The wavelength change of optical fiber is affected by strain and temperature, and can be expressed by the following formula:

[0044]

[0045] in,

[0046]

[0047] After eliminating the influence of temperature, the final strain calculation formula can be written as follows:

[0048]

[0049] in, The temperature calibration coefficient is taken as the average value of the four optical fibers above, which is 0.0110.

[0050] (6) Use cutting tools to cut the skin material and structural adhesive film (J-95) raw materials to form the required shape and quantity.

[0051] (7) Apply 700NC release agent to the working surface of the mold, let it dry for 20 minutes, then bake it in an oven at 50°C for 1 hour. Spray a metal transfer film on the surface of the release agent and let it dry for 40 minutes. Apply an arc-sprayed metal reflective layer with a thickness of about 0.25 mm.

[0052] (8) Overlap a layer of the cut structural adhesive film onto the surface of the metal layer, with an overlap width of no more than 10 mm; align the cut inner skin material radially with the apex of the mold convex surface as the center, with a joint gap width of no more than 2 mm; arrange the fiber optic grating sensor according to the layout diagram (see...). Figure 4 , Figure 5 The fiber optic grating sensor is attached to the first layer of prepreg, connected to the monitoring equipment, and the sensor input signal is checked to be normal. After vacuum sealing, it is cured for 16 hours, and the deformation data of the fiber optic grating sensor arrangement points on the reflective surface is monitored during the curing process.

[0053] (9) Remove the vacuum seal, disconnect the fiber optic grating sensor from the autoclave, overlap and cover the inner skin with a layer of the cut carrier film, with an overlap width of no more than 5 mm, and radially cover the cut aluminum honeycomb core material with the convex apex of the mold as the center, fill the gap with foam, connect the fiber optic grating sensor and the monitoring equipment, and check that the sensor input signal is normal. After vacuum sealing, cure for 9 hours and monitor the deformation data of the fiber optic grating sensor arrangement points on the reflective surface during the curing process.

[0054] (10) Remove the vacuum seal, disconnect the fiber optic grating sensor from the autoclave, fill the local reinforcement part of the aluminum honeycomb core with foam, connect the fiber optic grating sensor to the monitoring equipment, and check that the sensor input signal is normal. After vacuum sealing, cure for 9 hours and monitor the deformation data of the fiber optic grating sensor arrangement point on the reflective surface during the curing process.

[0055] (11) Remove the vacuum seal, disconnect the fiber optic grating sensor from the autoclave equipment, overlap and cover the surface of the aluminum honeycomb core material with a layer of cut carrier film, with an overlap width of no more than 5 mm, and radially overlap the cut outer skin material with the convex apex of the mold as the center, with the laying order being the opposite of the inner skin. The inner and outer skin layering structure is symmetrical with the center surface of the durable honeycomb core material. Connect the fiber optic grating sensor and the monitoring equipment, and check that the sensor input signal is normal. After vacuum sealing, cure for 17 hours.

[0056] (12) Remove the vacuum seal, disconnect the fiber optic grating sensor from the autoclave equipment, install the four supports at the corresponding positions of the cantilever beam of the support fixture, and tighten them; draw lines to determine the installation positions of the supports on the carbon fiber composite support body, and remove the corresponding material at the installation positions to form blind holes for installation.

[0057] (13) Prepare J-135 adhesive into a putty-like form, and bond the bottom of the four supports to the carbon fiber composite support as a whole, and cure at room temperature.

[0058] (14) Short carbon fiber filaments were added to J-135 adhesive to form a clump molding compound, which was then wrapped around the four supports. The supports and the carbon fiber composite material support formed a semi-embedded connection. The mixture was vacuum-sealed and cured at room temperature. The deformation data of the fiber optic grating sensor arrangement points on the reflective surface were monitored during the curing process.

[0059] (15) Remove vacuum encapsulation, use J-133 adhesive + carbon fiber to reinforce the support connection, and monitor the deformation data of the fiber optic grating sensor arrangement points on the reflective surface during the vacuum encapsulation room temperature curing process.

[0060] (16) Remove the vacuum seal, demold the whole thing, tidy up the appearance, and complete the manufacturing of the integral carbon fiber composite antenna reflector.

[0061] (17) The root mean square of the formed reflective surface is detected on a three-coordinate measuring machine.

[0062] (18) Using different process parameters, the reflective surface is formed, the deformation data of the reflective surface is collected and analyzed, the relationship between the forming and curing parameters and the surface deformation is found, the forming and curing parameters (heating and cooling rate, pressure point, etc.) are optimized, and the final forming and curing control curve is formed to realize the coupled deformation control of the reflective surface forming and to manufacture a reflective surface with high surface accuracy.

Claims

1. A coupling monitoring system for a carbon fiber microwave reflector, characterized in that: The coupling monitoring system for the carbon fiber microwave reflector is a device for detecting and recording the strain at various points during the forming of the microwave reflector. It includes a fiber optic grating sensor, a fiber optic cable through-wall pressure-resistant sealing device, a fiber optic grating sensor demodulator, and a data acquisition processor. The carbon fiber microwave reflector is a thin-walled parabolic surface of revolution, with a metallized reflective layer being the inner concave layer of the parabolic surface. The metallized reflective layer is made of sprayed aluminum. The support structure consists of a carbon fiber inner skin, an outer skin, an aluminum honeycomb, flanged flanges, and mounting and positioning supports bonded together with a structural carrier adhesive film. The inner and outer skins are located on the inner and outer surfaces of the aluminum honeycomb, forming a concave parabolic surface with the aluminum honeycomb. The outer edge is a flanged flange, and the mounting and positioning support is located on the outer surface of the parabola. The height of the mounting and positioning support from the bottom of the parabola is one-third of the total height of the parabola. Both the inner and outer skins are made of four layers of carbon fiber prepreg. The flanged flange is filled with foam to fill the aluminum honeycomb at the outer edge of the parabola. The mounting and positioning support is a metal insert with a titanium center. The metal insert is embedded in the aluminum honeycomb, and the junction between the metal insert and the aluminum honeycomb is filled with short fiber reinforced bulk molding compound. The reinforcing fibers of the short fiber reinforced bulk molding compound are 30 mm long alkali-free glass fibers, and the epoxy resin accounts for 80% by weight and the glass fiber accounts for 20% by weight. The data acquisition processor is connected to the optical cable through-wall pressure-resistant sealing device via a fiber optic grating sensor demodulator. The optical cable through-wall pressure-resistant sealing device leads out a sensor lead and connects the sensor lead to the monitoring point on the microwave reflector. The fiber optic grating sensor is attached to the first layer of carbon fiber prepreg on the inner skin of the microwave reflector. The microwave reflector is placed on a tooling cart. The microwave reflector, the fiber optic grating sensor, and the tooling cart are all located in the autoclave. The sensor lead passes through the autoclave and connects to the microwave reflector. The fiber optic cable through-wall pressure-resistant sealing device leads the signal of the fiber optic grating sensor out of the autoclave through the sensor lead. The fiber optic grating sensor demodulator converts the fiber optic grating sensor signal into digital data, which is then transmitted to the data acquisition processor for processing. By analyzing the changes in process parameters during the microwave reflector forming process, the coupling deformation data of the reflector is collected, and the process control parameters that ensure the accuracy requirements of the reflector forming surface are determined. The fiber optic cable through-wall pressure-resistant sealing device protects the optical fiber through the thermocouple wire pre-reserved hole in the autoclave body. The sensor lead is led out of the autoclave separately for monitoring. The fiber optic grating sensor is encapsulated with a heat-resistant polyimide protective film. The microwave reflector is formed by arc-spraying aluminum to create a metal powder accumulation layer of equal thickness, which is then bonded to the carbon fiber composite skin using a structural adhesive film.

2. The coupling monitoring system for carbon fiber microwave reflective surfaces according to claim 1, characterized in that: The fiber Bragg grating sensor is a fiber Bragg grating string with an operating temperature of -40~200℃, a grating spacing of 130±1mm, a protective film material of polyimide, a femtosecond point-by-point grating type, a grating length of 5±1mm, a reflectivity ≥50%, a bandwidth ≤0.4nm, a sealing pressure resistance ≥1.3MPa, and an fiber optic connector of FC / APC. The fiber Bragg grating sensors are evenly distributed on the inner side of the parabolic surface of the microwave reflector, consisting of six longitudinal lines and one circumferential line. The six longitudinal lines are all located on the generatrix on the inner side of the parabolic surface of the microwave reflector, and each pair of them forms a 60-degree angle with the center of the parabolic surface. Every two longitudinally distributed fiber Bragg grating sensors spaced 180 degrees apart form a monitoring channel. The circumferential line is evenly distributed around the edge of the inner side of the parabolic surface of the microwave reflector.

3. The coupling monitoring system for carbon fiber microwave reflective surfaces according to claim 1, characterized in that: The fiber grating sensor demodulator is an industrial-grade fanless Si155 demodulator with dynamic and static full-spectrum analysis capabilities and 4 channels with a 160nm bandwidth.

4. The coupling monitoring system for carbon fiber microwave reflective surfaces according to claim 1, characterized in that: The optical cable through-wall pressure-resistant sealing device is made by sealing the optical fiber inside a stainless steel sleeve. The optical fiber is led out as armored optical cable at both ends of the stainless steel sleeve. The sealing pressure inside the stainless steel sleeve is greater than or equal to 1.3MPa, the working temperature is -40~200℃, and the diameter of the stainless steel sleeve is 3mm.

5. The coupling monitoring system for carbon fiber microwave reflective surfaces according to claim 1, characterized in that: The inner and outer skins are made of plain weave fabric reinforced with epoxy resin prepreg in sheet roll form. The material consists of four layers of 0.1mm thick T800 carbon cloth, with the width achieved by splicing and the thickness by stacking the thickness of a single sheet.

6. The coupling monitoring system for carbon fiber microwave reflective surfaces according to claim 1, characterized in that: The core material of the aluminum honeycomb is a regular hexagonal honeycomb with a density of 53 kg / m³. 3 Corrosion resistance refers to the fact that after a 30-day salt spray test, the weight loss per unit area of ​​the exposed aluminum foil surface of the honeycomb core material does not exceed 0.135 mg / cm². 2 .

7. The coupling monitoring system for carbon fiber microwave reflective surfaces according to claim 1, characterized in that: The structural carrier film is a sheet-like thin roll material reinforced with nylon mesh at room temperature, with a volatile matter content of less than 1% and a flowability of greater than 55%.

8. The coupling monitoring system for carbon fiber microwave reflective surfaces according to claim 1, characterized in that: The spraying process of the microwave reflective surface is completed by aluminum wire arc spraying. First, a film-forming release agent is applied to the microwave reflective surface forming mold, then a polymer transfer film is sprayed, and then pure aluminum powder is arc sprayed on the outside of the polymer transfer film to form a uniform metal layer with a thickness greater than 0.25mm. Finally, it is bonded to the carbon fiber skin support body by structural adhesive film.

9. A molding control method for a coupling monitoring system utilizing the carbon fiber microwave reflective surface described in claim 1, characterized in that... Includes the following steps: The shaping of the microwave reflector surface is controlled in four steps in an autoclave, and the steps for controlling the shaping parameters are as follows: Step 1: The molding control parameters are the bonding molding and curing parameters for the metallized reflective layer and the carbon fiber inner skin of the microwave reflective surface support: pressure of 0.4MPa, heat preservation at 130℃ for 3 hours; Step 2: The molding control parameters are the bonding and curing parameters of the aluminum honeycomb of the microwave reflective surface support and the inner skin: pressure of 0.15MPa, heat preservation at 130℃ for 2.5 hours; Step 3: The molding control parameters are the local foaming and curing parameters for the aluminum honeycomb core material of the microwave reflective surface support: pressure of 0.15MPa, heat preservation at 130℃ for 2.5 hours; Step 4: The molding control parameters are the bonding and curing parameters for the carbon fiber outer skin of the microwave reflective surface support: pressure of 0.2MPa, heat preservation at 130℃ for 3 hours; Before use, the fiber optic grating sensor is calibrated at temperature to eliminate the effects of thermal expansion caused by temperature. The support of the microwave reflective surface is cured in four stages, including curing the metallized reflective surface spraying and bonding with the carbon fiber inner skin of the support, curing the aluminum honeycomb and inner skin, curing the aluminum honeycomb core material with local foam filling, and curing the carbon fiber outer skin. The curing control parameters are different for each stage as the structure changes. The mounting and positioning support is formed by two-stage adhesive bonding and room temperature curing. The metal insert at the center of the mounting and positioning support is made by impregnating fiberglass chopped strand mat with J-135 adhesive and curing it at room temperature for 24 hours under mechanical pressure, bonding it to the inner skin and aluminum honeycomb of the support body. Then, chopped glass fiber filaments are added to J-135 adhesive to form a clump molding compound, which is used to wrap around the metal insert of the mounting and positioning support and cured at room temperature. Finally, carbon fiber plain weave cloth and J-133 adhesive are laid down for reinforcement, vacuum sealed and cured at room temperature.

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