Near-zero warping forming method and system for resin-based composite material plane part

Abstract

The invention discloses a near-zero warping forming method and system for a resin-based composite material plane piece, and belongs to the technical field of composite material forming. According to the method, aiming at the problem that the large-size composite material plane piece for the satellite is prone to buckling deformation in the curing process, a dynamic temperature field is actively constructed to regulate and control the curing reaction sequence, stress localization is achieved, long-range stress superposition is reduced, buckling deformation is reduced, and near-zero-buckling forming is achieved. The method comprises the following steps: designing dynamic temperature field distribution based on multi-physics field coupling simulation; a heating unit array capable of independently controlling temperature and a thermocouple monitoring system are arranged on the surface of the mold; laying a to-be-formed part and a mold; packaging in a vacuum bag, vacuumizing, and curing according to a set temperature curve; and cooling and demolding after curing. According to the method, stress localization is achieved through active regulation and control of the temperature field, stress long-range superposition is reduced, and buckling deformation in the curing process is remarkably restrained.

Description

Technical Field

[0001] This application belongs to the field of composite material molding technology, specifically relating to a near-zero warpage molding method and system for resin-based composite planar parts. Background Technology

[0002] Resin-based composite materials, especially fiber-reinforced resin-based composite materials, have found extremely wide application in the aerospace field due to their excellent specific strength, specific modulus, fatigue resistance, and designability. Their applications have expanded from satellite structures to fairings, instrument panels, and bulkheads for launch vehicles and sounding rockets, as well as large radomes, fairings, and high-performance platform panels in spacecraft and launch vehicle ground equipment. Many key components in these spacecraft and ground equipment, such as satellite communication radomes, rocket antenna fairings, and instrument mounting plates, are large-sized planar or low-curvature curved surface components. During service, they not only withstand harsh mechanical environments but also face near-stringent requirements regarding their geometric accuracy (flatness, surface accuracy) and dimensional stability.

[0003] However, during the curing process, composite materials often experience uneven stress due to temperature distribution, leading to internal stress concentration and problems such as product warping and deformation, which affect their performance and assembly accuracy. For example, warping of a wave shield directly affects the transmission performance of electromagnetic waves; deformation of instrument mounting plates affects the alignment and installation of precision equipment; and the splicing accuracy of large fairings directly affects their aerodynamic shape.

[0004] Furthermore, for sandwich structures with foam cores, the significant difference in thermal expansion coefficients between the core and panel materials makes them more prone to warping during curing. Simultaneously, composite materials often warp during curing due to material anisotropy and mismatched thermal expansion coefficients between the core and panel, severely impacting assembly accuracy and service performance. Traditional uniform temperature field curing methods struggle to effectively control warping in such structures, hindering the large-scale production of high-precision planar composite products.

[0005] For next-generation large-scale, thin-walled, and highly integrated aerospace components, such as large-size planar parts like solar panel substrates and antenna reflectors, extremely high requirements are placed on surface accuracy and flatness. Traditional autoclave curing processes, due to their singular heating method and poor temperature field uniformity, struggle to effectively control warpage. Existing research largely focuses on optimizing process parameters or mold compensation, while methods for actively controlling the temperature field distribution to reconstruct residual stress and achieve near-zero warpage remain relatively scarce.

[0006] Therefore, developing a high-precision molding method that can actively control stress at its source and achieve near-zero warpage is of urgent need and great significance for improving the manufacturing level and performance of products such as launch vehicles, satellites, and aerospace ground equipment. Summary of the Invention

[0007] The purpose of this invention is to provide a near-zero warpage molding method for planar resin-based composite materials, which is particularly suitable for molding multi-layer composite structures with foam core materials. This method solves the technical problem of warpage deformation in composite material products. By constructing a zoned dynamic temperature field and using multiple independently temperature-controlled heating units, the temperature distribution of the composite material during the curing process is precisely controlled, the curing sequence is adjusted, stress is localized, long-range stress accumulation is reduced, warpage deformation is effectively suppressed, and high-precision molding of planar resin-based composite materials is achieved.

[0008] A method for molding near-zero warpage of a resin-based composite planar part includes the following steps: Step S1: Based on multi-physics coupling simulation, design dynamic temperature field distribution, and arrange heating unit array and corresponding temperature monitoring unit that can independently control temperature in zones on the lower surface of the forming mold; Step S2: Perform composite material layup on the mold; Step S3: Vacuum bag the layup system and evacuate it, and control each heating zone to heat and cure according to the preset, different dynamic temperature curves; Step S4: After curing, cool and demold to obtain the resin-based composite material planar part.

[0009] Step S1 includes a dynamic temperature field design step: based on the component size and structural characteristics, design multiple independently temperature-controlled heating units and their distribution, and in conjunction with the curing process, determine the dynamic temperature curve of each heating unit through multi-physics field coupling simulation. In step S1, heating units and temperature monitoring units (thermocouples) are arranged on the lower surface of the mold. The temperature monitoring units are arranged in the central area of ​​each heating unit, and each unit is connected to a multi-channel temperature control system for real-time monitoring and control of temperature.

[0010] The heating units and thermocouples are fixed with high-temperature resistant tape or clamps. The wires of all heating units and thermocouples are organized and gathered together, with sufficient length reserved for subsequent lead-out of the vacuum bag. The wires of each heating unit are connected to the independent power output channel of the multi-channel temperature control system, and the wires of each thermocouple are connected to the corresponding temperature signal acquisition channel of the temperature control system, forming multiple independent closed-loop control circuits.

[0011] In step S1, multiphysics coupling simulation software is used to establish a thermo-curing-mechanical coupling model to simulate the distribution of temperature field, curing degree field and residual stress field during the curing process, and optimize the temperature setting curve of each heating unit. The temperature difference range of different temperature curves is 5℃-30℃.

[0012] The dynamic temperature field refers to the process in which different regions on the plane independently experience different temperature processes (including heating rate, peak temperature, and holding time) according to a preset program during the curing process, so as to regulate the local curing sequence and stress development.

[0013] The heating units are sheet heaters arranged in an array on the lower surface of the mold. Each heating unit is independently temperature-controlled. The thermocouples are connected to a multi-channel temperature control system to achieve closed-loop temperature control. Specifically, a suitable-sized first breathable material is laid at the bottom layer. A corresponding number of sheet heaters are placed on its surface according to the calculated distribution of the heating units. These are then attached to the first breathable material with insulating tape. A thermocouple is also attached to the center of each sheet heater with insulating tape for real-time temperature monitoring.

[0014] Furthermore, the term "sheet heater" here is used in a general sense. Sheets include, but are not limited to, rectangular, circular, and rhomboid shapes, which can be selected according to specific heating needs and simulation conditions. Heater types also include, but are not limited to, metal, mica / metal, and graphene, which can be selected according to specific performance requirements.

[0015] Furthermore, the breathable material is a breathable felt.

[0016] In step S1, the dynamic temperature field includes, but is not limited to, at least one of the following distribution patterns: a centrally symmetric temperature field, a length-direction symmetric temperature field, a width-direction symmetric temperature field, etc., which can be designed according to the specific parameters of the component and its warping trend.

[0017] In step S2, based on the completion of the heating system construction in step S1, further composite material layup and mold placement are carried out. Specifically, the layup is as follows: multiple layers of resin (epoxy, cyanate, bismaleimide, polyimide) and fiber (carbon fiber, glass fiber, quartz, aramid and their mixed fibers) prepregs are laid on the foam core material to form a multi-layer composite structure including the core material and the surface; the laid composite material is placed in the mold, and release cloth and breathable felt are covered on the top and bottom in sequence, and a release film is placed between the mold and the lower release cloth.

[0018] Specifically, the composite material to be molded is laid up as follows: resin-fiber prepreg is laid up above and below the foam core material in the required number and angle, forming a multi-layer composite structure in the form of "prepreg-foam-prepreg".

[0019] Both "resin" and "fiber" are general terms. Resins include thermosetting resins such as epoxy resin, cyanate ester, bismaleimide resin, and thermosetting polyimide resin. Fibers include, but are not limited to, carbon fiber, glass fiber, quartz fiber, aramid fiber, and other fibers and their blends.

[0020] The specific layering sequence is as follows: the bottom layer is the breathable material with heater and thermocouple arranged in step S1, and then the layers are steel plate mold, isolation film, first release cloth, part to be formed, second release cloth, heat insulation board, and second breathable material.

[0021] The first and second release fabrics are made of the same material, type, and shape. The heat insulation board is a tempered glass board, and the breathable material is a breathable felt. The first and second breathable materials, i.e., the breathable felt, are also made of the same material, type, and shape.

[0022] In step S3, all the layers completed in step S2 are placed into a vacuum bag and sealed. Before sealing, the lead bundles of the heating unit and thermocouples are carefully led out from the sealing strips pre-laid at the edge of the vacuum bag, ensuring that all leads are tightly wrapped with sealant to form a reliable airtight seal. A vacuum system is connected through the vacuum nozzle pre-installed on the vacuum bag to evacuate (e.g., below -0.095 MPa). The pressure is determined based on the layer thickness and curing process. The mica heater and thermocouple leads extending from the vacuum bag are connected to the heating system, and heating and curing are performed according to the set curing temperature curve. Specifically, the heater leads are connected to the heating output terminals of the multi-channel temperature controller, and the thermocouple leads are connected to the corresponding temperature acquisition terminals. The system is started, and the temperature control system drives each heating unit to work independently based on the preset dynamic temperature curves for each zone and the real-time feedback from the thermocouples, achieving dynamic temperature field curing in each zone.

[0023] For the upper and lower sealing parts of the vacuum bag, sealant is used for bonding. The wire extends to the outside through the sealant. Sealant is applied to the part where the wire contacts the sealant to make it tightly bonded to the upper and lower vacuum bags, ensuring that there is no air leakage after sealing.

[0024] In step S3, the pressure inside the vacuum bag is maintained below -0.1 MPa to ensure that the composite material is in a uniform pressure environment during the curing process. Depending on the thickness of the layup and the requirements of different curing processes, it can be placed in a pressure vessel for pressurization, with a pressure range of 0.1MPa-1MPa.

[0025] In step S4, after curing, the material is naturally cooled to room temperature in a vacuum environment. After stabilizing at room temperature, the power is turned off, the vacuum is released, and the material is demolded to obtain a near-zero warpage resin-based composite material planar part.

[0026] The principle of this invention is that by using a partitioned dynamic temperature field, different regions of the composite material plane are deliberately made to reach the gel point and fully cured state at different times. The shrinkage stress generated in the first cured region is absorbed or relaxed by the surrounding material parts that are still in a viscous flow state or uncured, thereby dividing the large-scale, synergistic shrinkage stress into multiple localized, non-synergistic stress fields. These local stress fields partially cancel each other out during the subsequent overall curing process, ultimately significantly reducing the net residual stress that causes macroscopic warping.

[0027] The "dynamic temperature field" refers to the process in which, during the curing of composite materials, different regions within the plane of the product independently experience different temperature processes according to a preset program through an array of independently controlled heating units. This includes differences in heating rate, peak temperature, and holding time, thereby actively regulating the local curing reaction process and residual stress development in different regions.

[0028] This application also provides a molding system for implementing a near-zero warpage molding method for a resin-based composite planar part, which is used to implement the near-zero warpage molding method for a resin-based composite planar part as described in any of the preceding claims, including a heating unit array with independent temperature control in zones, a multi-channel temperature control system, a vacuum bag sealing system, and a temperature monitoring system. The heating unit array is led out through the vacuum bag sealing area by high-temperature resistant wires and is independently connected to the power output terminal of the multi-channel temperature control system. The temperature monitoring system includes thermocouples arranged in each heating zone. The thermocouples are led out through the vacuum bag sealing area by compensating wires and connected to the signal input terminal of the multi-channel temperature control system to form a closed-loop temperature control loop for each zone.

[0029] The technical details not described in this solution are based on the conventional understanding and operation of those skilled in the art, and can be implemented in conjunction with existing technology, and will not be elaborated here.

[0030] The positive effects of this invention are that, compared with existing curing and molding technologies, it can significantly improve the molding accuracy of planar resin-based composite materials during curing and molding, specifically in the following aspects: (1) By designing a partitioned dynamic temperature field, this invention effectively compensates for the uneven curing of composite materials caused by differences in the structure and thermal expansion coefficients of the materials, significantly reducing the warpage deformation of the product (the maximum warpage height is reduced by about 60% compared to a uniform temperature field). Compared with the traditional uniform heating method, it achieves near-zero warpage molding of resin-based composite planar parts while ensuring the mechanical properties of the product, thus improving the assembly accuracy and service performance of the product. It fundamentally ensures the surface accuracy and dimensional stability of key components such as satellite domes, rocket antenna covers, and instrument mounting platforms, laying the foundation for high-precision assembly and superior electrical and mechanical properties.

[0031] (2) The use of an independent temperature-controlled heating unit and a closed-loop temperature control system improves the temperature control accuracy and response speed. Compared with the traditional autoclave heating and curing method, it saves energy and improves the molding consistency. It is particularly suitable for the stable mass production needs of large and complex aerospace composite material components, significantly reduces the dependence on mold compensation and subsequent repair work, shortens the manufacturing cycle and reduces costs.

[0032] (3) This invention is also applicable to the molding of high-precision planar parts such as composite materials with foam interlayer, and has good engineering applicability and scalability; it can also be widely used in the manufacturing of planar or low curvature components such as fairings and cabin partitions of launch vehicles and sounding rockets, as well as large antenna domes, fairings, and high stability platforms in various aerospace ground equipment, with strong engineering applicability and scalability.

[0033] (4) The innovation of this invention lies in proposing a method for actively constructing a partitioned dynamic temperature field to regulate stress. By designing and implementing a controllable dynamic temperature distribution in different partitions within the molding plane, the curing sequence of the composite material during the curing process is actively intervened and reconstructed, thereby affecting the residual stress field. The aim is to counteract or balance the stress sources that cause warping from the root, and achieve a "fundamental" warping suppression. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the heating unit arrangement in this invention.

[0036] Figure 2 This refers to the layup method of the composite material to be molded part in this invention.

[0037] Figure 3 This is a schematic diagram (main sectional view) of the composite material and mold layup structure in this invention.

[0038] The attached figures are labeled as follows: 1-first breathable material; 2-thermocouple; 3-sheet heater; 4-wire; 5-foam core material; 6-resin-fiber prepreg; 7-vacuum nozzle; 8-vacuum bag; 9-second breathable material; 10-heat insulation board; 11-second release cloth; 12-part to be molded; 13-first release cloth; 14-isolation film; 15-steel plate mold. Detailed Implementation

[0039] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0040] To illustrate this method in detail, the following description uses cyanate ester resin-based glass fiber composite material as an example. Those skilled in the art should understand that this example is not intended to limit the scope of the invention; for other resin systems (such as epoxy, bismaleimide, polyimide, etc.), the same technical principles and processes can be applied by adjusting the simulation parameters.

[0041] Example 1 See Figures 1-3 A near-zero warpage molding method for resin-based composite materials, specifically including the following steps: Step S1: Based on multi-physics coupling simulation, design dynamic temperature field distribution, and arrange heating unit arrays and corresponding temperature monitoring units that can independently control temperature in zones on the lower surface of the forming mold.

[0042] A multiphysics model was established using multiphysics coupling simulation software, and a thermo-curing-mechanical coupling model was established. For a planar component with dimensions of 500mm × 300mm and containing foam core material 5, the dynamic temperature field was simulated and optimized. In this embodiment, the foam core material 5 is PMI foam core material. The temperature curves of six independent heating units were optimized to form a centrally symmetric non-uniform temperature field, divided into high, medium, and low temperature levels with a temperature difference of 15℃ between zones, with the medium temperature being low. Based on the simulation results, the independent temperature-time curves of each heating unit were determined. A sheet heater 3 and thermocouple 2 were arranged, and the curing temperature rise curves for each region were set on the temperature control system. In this embodiment, the sheet heater 3 is a mica heater. Next, the physical arrangement is carried out. A first breathable material 1 is laid as the bottom layer. According to the design, six symmetrically distributed sheet heaters 3 (80×80mm, 100W) are arranged on its surface and fixed with high-temperature resistant insulating tape. At the center of each sheet heater 3, a thermocouple 2 is also fixed with insulating tape as the temperature monitoring unit for that zone. In this embodiment, the thermocouple 2 is a type K thermocouple. The wires 4 of all sheet heaters 3 and thermocouples 2 are arranged and sufficient length is reserved.

[0043] In step S1, the temperature field, degree of curing field, and residual stress field during the curing process are simulated to optimize the temperature distribution curves of each heating unit and determine the temperature distribution corresponding to the stress field that is beneficial to reducing the warping of the molded part. The specific simulation method can be implemented by those skilled in the art using simulation software, and will not be detailed here.

[0044] Step S2: Lay up the composite material on the mold.

[0045] The composite material part 12 with a multi-layer structure of "prepreg-foam-prepreg" is prepared, and all layup steps from the mold to the part 12 are completed before vacuum sealing.

[0046] In step S2, as Figure 1 As shown, the first breathable material 1 is laid at the bottom layer. Six symmetrically distributed sheet heaters 3 (80×80mm, 100W) are placed on the surface of the first breathable material 1 according to the heating unit distribution method calculated in step S2. They are then attached to the first breathable material 1 with insulating tape. At the center of each sheet heater 3, a thermocouple 2 is also attached with insulating tape for real-time temperature monitoring.

[0047] On top of this, steel plate mold 15, release film 14, first release cloth 13, part to be formed 12, second release cloth 11, heat insulation board 10, and second breathable material 9 are placed in sequence. The main sectional view of the specific layer structure is shown below. Figure 3 As shown.

[0048] For part 12 to be formed, such as Figure 2 As shown, this study takes a 500mm × 300mm satellite composite flat component as an example. The core material is a 1.6mm thick foam core material 5, with a 0.2mm thick cyanate ester / glass fiber prepreg (i.e., resin-fiber prepreg 6) layer laid on top and bottom, forming a three-layer sandwich structure of "prepreg-foam-prepreg". It is then pre-compacted manually or with an iron to ensure flatness and no air bubbles. Preliminary layering and lamination are performed, for example, by manual or ironing heat-pressure coupling, to ensure the three-layer composite component 12 is flat and air bubble-free, resulting in the component 12 in the above-mentioned layering steps.

[0049] The first and second release fabrics are made of the same material, type, and shape. Similarly, the first and second breathable materials are made of the same material, type, and shape, and both breathable materials are breathable felt. The heat insulation plate 10 is a tempered glass plate.

[0050] Step S3: Vacuum bag the layup system and evacuate it, then control each heating zone to heat and cure according to preset, different dynamic temperature curves.

[0051] In step S3, the layers laid up in the above steps are sealed with a vacuum bag 8. The wires 4 of the sheet heater 3 and the thermocouple 2 extend out through the sealant. The sealant is applied appropriately to the part where the wires 4 come into contact with the sealant to ensure that the sealing bag 8 is sealed well and no air leakage occurs.

[0052] Connect the sheet heater 3 and the wires 4 of the thermocouple 2 to the 6 independent heating output channels of the multi-channel temperature controller, and connect the wires 4 of the thermocouple 2 to the 6 corresponding temperature feedback input channels of the temperature controller for subsequent curing heating and temperature control.

[0053] Vacuum nozzles 7 are pre-installed at the corresponding size holes reserved on the vacuum bag 8. They are connected to the vacuum system (vacuum pump) to evacuate to -0.1MPa. After ensuring no air leakage, the temperature control system is turned on to perform curing heating.

[0054] After verifying that the system is working correctly, the multi-channel temperature controller is started. The temperature controller drives the six plate heaters 3 to work simultaneously according to the six different temperature curves preset in step S1, and performs closed-loop PID control based on the real-time feedback of the corresponding thermocouples 2, thereby accurately constructing the required centrally symmetric dynamic temperature field in the plane of the composite material for curing.

[0055] Step S4: After curing, cool and demold to obtain the resin-based composite material planar part.

[0056] Once all zones have completed the set curing temperature curve, i.e., after curing is complete, turn off the heating system power and allow it to cool naturally to room temperature in a vacuum while maintaining a vacuum. After demolding, the desired near-zero warpage flat part is obtained.

[0057] In step S4, when the curing curve reaches its endpoint, the material is kept under vacuum and allowed to cool naturally to room temperature. The cooling process can still be monitored using the temperature control system. After all areas have cooled to room temperature, the vacuum system is turned off, all power is switched off, and the mold is demolded. Auxiliary materials are removed sequentially, and finally, the formed composite material planar part is removed from the steel plate mold 15, resulting in the desired planar part with near-zero warpage. Measurements show that the planar part formed using the method of this embodiment has a maximum warpage height of approximately 0.2 mm. Compared to the control part formed using the same mold and material but with the same uniform temperature curve in all areas (maximum warpage height approximately 0.5 mm), the warpage deformation is reduced by approximately 60%, achieving the goal of near-zero warpage.

[0058] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for molding near-zero warpage of a resin-based composite planar part, characterized in that: Includes the following steps: Step S1: Based on multi-physics coupling simulation, design dynamic temperature field distribution, and arrange heating unit array and corresponding temperature monitoring unit that can independently control temperature in zones on the lower surface of the forming mold; Step S2: Perform composite material layup on the mold; Step S3: Vacuum bag the layup system and evacuate it, and control each heating zone to heat and cure according to the preset, different dynamic temperature curves; Step S4: After curing, cool and demold to obtain the resin-based composite material planar part.

2. The near-zero warpage molding method for resin-based composite planar parts as described in claim 1, characterized in that: Before arranging the heating unit array capable of independent temperature control in different zones and the corresponding temperature monitoring units, a dynamic temperature field design step is also included: based on the component size and structural characteristics, multiple independently temperature-controlled heating units and their distribution are designed, and combined with the curing process, the dynamic temperature curve of each heating unit is determined through multi-physics field coupling simulation. In step S1, heating units and temperature monitoring units are arranged on the lower surface of the mold. The temperature monitoring units are arranged in the central area of ​​each heating unit, and each unit is connected to a multi-channel temperature control system for real-time monitoring and control of temperature.

3. The near-zero warpage molding method for resin-based composite planar parts as described in claim 2, characterized in that: In step S1, multiphysics coupling simulation software is used to establish a thermo-curing-mechanical coupling model to simulate the distribution of temperature field, curing degree field and residual stress field during the curing process, and optimize the temperature setting curve of each heating unit. The temperature difference range of each zone temperature curve after optimization is 5℃-30℃.

4. The near-zero warpage molding method for resin-based composite planar parts as described in claim 2, characterized in that: The heating unit is a plate heater, arranged in an array on the lower surface of the mold, and each heating unit is independently temperature controlled; the temperature monitoring unit is a thermocouple, which is connected to a multi-channel temperature control system, arranged at the center or feature point of the corresponding heating zone, and realizes closed-loop temperature control.

5. The near-zero warpage molding method for resin-based composite planar parts as described in claim 2, characterized in that: In step S1, the dynamic temperature field includes, but is not limited to, at least one of the following distribution patterns: a centrally symmetric temperature field, a length-direction symmetric temperature field, and a width-direction symmetric temperature field.

6. The near-zero warpage molding method for resin-based composite planar parts as described in claim 1, characterized in that: In step S2, the layup structure is a sandwich structure containing a foam core material, specifically: a panel layer formed of resin-based prepreg is laid on the upper and lower surfaces of the foam core material; the resin of the resin-based prepreg is one of epoxy resin, cyanate ester resin, bismaleimide resin or polyimide resin, and the reinforcing fiber is one or more of carbon fiber, glass fiber, quartz fiber or aramid fiber. Place the laminated composite material in the mold, and cover it with release cloth and breathable felt in sequence. Place a release film between the mold and the lower release cloth.

7. The near-zero warpage molding method for resin-based composite planar parts as described in claim 6, characterized in that: In step S3, all the layers completed in step S2 are placed into a vacuum bag and sealed. A vacuum system is connected to evacuate the vacuum. The pressure is determined according to the layer thickness and curing process. The heating system is then connected to heat and cure the layers according to the set curing temperature curve.

8. The near-zero warpage molding method for resin-based composite planar parts as described in claim 1, characterized in that: In step S3, the pressure inside the vacuum bag is maintained below -0.1 MPa to ensure that the composite material is in a uniform pressure environment during the curing process. Depending on the thickness of the layup and the requirements of different curing processes, it can be placed in a pressure vessel for pressurization, with a pressure range of 0.1MPa-1MPa.

9. The near-zero warpage molding method for resin-based composite planar parts as described in claim 1, characterized in that: In step S4, after curing, the material is naturally cooled to room temperature in a vacuum environment. After the vacuum is released, the material is demolded to obtain a near-zero warpage resin-based composite planar part.

10. A near-zero warpage molding system for planar resin-based composite materials, characterized in that: The method for realizing near-zero warpage molding of resin-based composite planar parts as described in any one of claims 1-9 includes a heating unit array with independent temperature control in zones, a multi-channel temperature control system, a vacuum bag packaging system, and a temperature monitoring system. The heating unit array is led out through the vacuum bag sealing area by high-temperature resistant wires and is independently connected to the power output terminal of the multi-channel temperature control system. The temperature monitoring system includes thermocouples arranged in each heating zone. The thermocouples are led out through the vacuum bag sealing area by compensating wires and connected to the signal input terminal of the multi-channel temperature control system to form a closed-loop temperature control loop for each zone.

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