A method for molding composite material test plates and molding composite parts in a furnace

Abstract

This application relates to the field of composite material molding technology and discloses a method for molding composite material test plates in a furnace, including the following steps: S1: main material preparation; S2: mold preparation; S3: pre-laying inspection; S4: laying; S5: encapsulation; S6: curing; S7: demolding; S8: inspection.

Description

Technical Field

[0001] This application relates to the field of composite material molding technology, and in particular to a method for molding composite material test plates and parts in a furnace. Background Technology

[0002] The performance and defects of composite parts are closely related to the manufacturing process, but the molding process is unpredictable, and it is impossible to directly cut large batches of samples from the final product. In the prior art, furnace-fed parts are used for process monitoring and quality assessment, but for special products with complex layups, conventional furnace-fed parts are difficult to effectively characterize their performance and molding quality. Summary of the Invention

[0003] The purpose of this application is to provide a method for molding composite material test plates in a furnace, including the following steps: S1: Main material preparation: Take the prepreg material out of the frozen environment, check the storage expiration date, remaining operating life and remaining mechanical property life of the material, and ensure that the remaining operating life is >0h and the remaining mechanical property life is >0h; Thaw the material for no less than 8 hours. Thawing is considered complete when the outer packaging is wiped dry and no water droplets or moisture condense. S2: Mold preparation: Confirm that the material of the mold for the furnace parts is consistent with the material of the product mold, clean the mold surface, and apply release agent; S3: Pre-installation inspection: Check the ambient temperature, humidity, and the validity period of the measuring instruments; S4: Laying: Lay the prepreg layer by layer on the mold according to the layup schedule. After each layer of prepreg is laid, check whether the fiber direction is consistent with the angle in the layup schedule. Use a scraper and / or a blower to assist heating along the fiber direction to remove air bubbles and smooth out wrinkles. During the laying process, retain the backing release paper and release film. After laying, count and check to ensure that there are no foreign objects. Perform vacuum pre-compaction according to the layer sequence required in the layup schedule. The vacuum degree of vacuum pre-compaction is -100KPa to -80KPa, and the holding time is not less than 15 minutes. After the last layer is laid, perform vacuum compaction. The vacuum degree of vacuum compaction is -100KPa to -85KPa, and the holding time is not less than 1 hour. S5: Encapsulation: Place the pressure equalizing plate, use vacuum curing auxiliary material to assemble a vacuum bag for sealing, and perform vacuum degree testing. Stop vacuuming when the pressure value of all test points is -100KPa to -85KPa. It is required that the vacuum degree decay value of all test points is not greater than 5KPa within 15 minutes. S6: Curing: The encapsulated mold is placed into an autoclave, and the curing parameters are set for curing. S7: Demolding: After the product temperature naturally drops to room temperature, remove the auxiliary materials and separate the parts from the mold; S8: Inspection: Perform surface quality inspection on parts.

[0004] Optionally, in S1, an automatic fabric cutting machine is used for material preparation. When cutting the prepreg, the length edge of the roll is required to coincide with the 0° line of the machine. The fiber direction angle deviation is: ±2° for unidirectional prepreg and ±3° for woven prepreg. The allowable deviation of the material sheet size is ±2.5mm.

[0005] Optionally, in step S1, after the cut material pieces are packaged and labeled with the part name and drawing number, they are transferred to the installation station. If installation is not planned to start within 48 hours, the cut material pieces are bagged and stored back in the freezer. They are then thawed before the installation process begins.

[0006] Optionally, in step S2, a white cotton cloth, cleaning agent, plastic scraper, and vacuum cleaner are used to clean dust and adhesive residue from the mold and tooling surfaces; masking tape is used to isolate and protect the sealing strip area for bag making.

[0007] Optionally, in step S2, the mold is applied with 5 coats of release agent for the first use or after cleaning with a cleaning agent. After each part is demolded, 3 coats of release agent are applied. The interval between each coat of release agent is at least 15 minutes. The next process is carried out at least 30 minutes after the last coat of release agent is applied.

[0008] Optionally, in step S2, instead of applying a release agent, a method of using an adhesive-backed fluorinated release cloth can be used to ensure the release effect.

[0009] Optionally, in step S3, the ambient temperature is 22±4℃ and the ambient humidity is ≤60%.

[0010] Optionally, in S4, the forming process of the furnace-fed parts is kept as consistent as possible with the product.

[0011] Optionally, in step S4, the vacuum precompaction uses a vacuum precompaction auxiliary material group to make the vacuum bag, the vacuum precompaction auxiliary material group including a porous isolation membrane, a release cloth, a breathable felt and a vacuum bag film.

[0012] Optionally, in S5, the vacuum curing auxiliary material group includes a release cloth, a non-porous release film, a breathable felt, and a vacuum bag film.

[0013] Optionally, in step S5, the equalizing plate is slightly smaller than the material sheet and is placed in the center. The equalizing plate is cured together with the material sheet inside the vacuum bag. The vacuum bag has pleats evenly and symmetrically arranged.

[0014] Optionally, in step S6, the remaining working life of the material is ensured to be >0h before the laying process is completed; and the remaining mechanical property life of the material is ensured to be >0h before the heating equipment is turned on for curing.

[0015] Optionally, in S7, a nylon release wedge is gradually inserted along the gap between the edge of the part and the mold, and gently pried to separate the part from the mold.

[0016] This application also provides a method for forming parts in a furnace, including the following steps: S9: Select the type of furnace-fed component, which includes pure fabric furnace-fed component, unidirectional belt furnace-fed component, and sandwich furnace-fed component; S10: Determine the layup scheme according to the selected furnace component type: fabric furnace component layup is 0 / 90°n, unidirectional belt furnace component layup is 0°n, and sandwich furnace component layup is 45° / 0° / PMI / 0° / 45°. S11: The furnace-mounted component is formed using the method steps described in any one of claims 1 to 13.

[0017] Optionally, the core component used in the furnace is a 5mm foam core. Attached Figure Description

[0018] Figure 1 The diagram shows a flow chart of the method for forming composite material test plates in the furnace according to this application. Figure 2 This is another schematic diagram of the method for forming composite material test plates in the furnace according to this application; Figure 3 This is another schematic diagram of the method for forming composite material test plates in the furnace according to this application; Figure 4 This is another schematic diagram of the method for forming composite material test plates in the furnace according to this application; Figure 5 The diagram shown is a schematic flow chart of the furnace-mounted part forming method of this application. Detailed Implementation

[0019] The following embodiments further illustrate the technical solutions of this application. It should be understood that the specific embodiments described herein are merely for explaining this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not all of them.

[0020] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0021] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] The term "aircraft" is defined as an air transport system of any size having at least one lift propeller as its propulsion source. The term "aircraft" can include both "manned" and "unmanned" air transport systems. A manned aircraft can mean an air transport system carrying one or more human passengers, none of whom have control over the aircraft. A manned aircraft can also mean an air transport system carrying one or more human passengers, some of whom, or one of whom, has partial or full control over the aircraft. An unmanned aircraft can mean an air transport system that does not carry any human passengers and flies autonomously or is remotely controlled by someone at a distance.

[0023] In this specification, "aircraft" includes manned aircraft and any unmanned vehicle, such as unmanned aerial vehicles (UAVs), unmanned aircraft, remote-controlled aircraft, unmanned aircraft systems, any aircraft classified by the International Civil Aviation Organization (ICAO) under cycle 328AN / 190, and so on. As an example, a drone can take the form of a single- or multi-rotor helicopter (such as a quadcopter) or a fixed-wing aircraft. Furthermore, certain portions of this disclosure can be used in conjunction with drones in the form of other types of unmanned vehicles (e.g., wheeled, tracked, and / or watercraft).

[0024] The embodiments of this application are described below with reference to the accompanying drawings, which provide a detailed description of a specific implementation of the present invention.

[0025] I. Specific Implementation Methods for Main Ingredient Preparation Steps Main material preparation is a fundamental process for forming trial plates in the furnace. Its purpose is to ensure that the raw materials are in a usable state and to complete the material preparation work before laying.

[0026] First, operators remove the prepreg material from the frozen environment and check its storage expiration date, remaining operational life, and remaining mechanical property life. Prepreg is the basic raw material for composite molding, and its lifespan is affected by ambient temperature, humidity, and storage time. Operators must verify the label information on the material packaging to ensure that the remaining operational life and remaining mechanical property life are greater than 0 hours. If any of these life parameters do not meet the requirements, the batch of material must not be used.

[0027] During the material thawing process, after the prepreg is removed from the frozen environment, the thawing time should not be less than 8 hours. During thawing, the outer packaging must not be opened or damaged to prevent moisture from condensing on the surface of the prepreg and causing contamination. If the packaging bag is found to be damaged during handling, it must be immediately sealed with tape, and the damage must be recorded. Operators must record the start and end times of thawing. Thawing is considered complete when the outer packaging is wiped dry and no more water droplets or moisture condense.

[0028] In the material preparation stage, operators use an automatic fabric cutting machine to prepare the materials. The automatic fabric cutting machine automatically cuts the fabric sheets according to the preset cutting program. When cutting prepreg, the length edge of the roll must coincide with the 0° line of the machine to ensure that the fiber direction is consistent with the cutting direction. Regarding the fiber direction angle deviation, unidirectional prepreg is generally ±2°, and woven prepreg is generally ±3°. The allowable deviation in the size of the fabric sheets is ±2.5mm. After cutting, operators check the quantity and markings of the fabric sheets. The fabric sheet packaging is marked with the part name and drawing number before being transferred to the laying station. If laying is not planned to start within 48 hours, the cut fabric sheets are bagged separately, stored in a frozen environment, and thawed again before the laying process begins.

[0029] II. Detailed Implementation of Mold Preparation Steps Mold preparation is a key process to ensure the quality of the molded parts and smooth demolding.

[0030] First, the operators confirm that the material of the mold for the furnace-mounted component is consistent with that of the product mold. This consistency ensures comparability between the furnace-mounted component and the product in terms of thermal expansion behavior, surface quality, and heat transfer characteristics, thus allowing the performance characterization results of the furnace-mounted component to accurately reflect the product's technological state.

[0031] Next, the operator confirms that the mold is in normal condition and records the mold number. They also confirm that the mold markings and markings are complete and clear, as these guide the positioning of the sheet material and the alignment of the fibers during installation.

[0032] During the mold cleaning process, operators use white cotton cloths, cleaning agents, plastic scrapers, and vacuum cleaners to clean dust and adhesive residue from the mold and tooling surfaces. The white cotton cloths make it easy to observe whether any stains remain after cleaning, the plastic scrapers are used to remove stubborn adhesive residue without damaging the mold surface, and the vacuum cleaners are used to remove dust particles.

[0033] During the isolation and protection process, operators use masking tape to isolate and protect the area of ​​the sealing strip used for bag making, in order to prevent the sealing strip from directly contacting the mold surface and causing difficulties in subsequent cleaning.

[0034] During the application of release agent, operators must wear masks, gloves, and protective goggles. Applying release agent inside the installation area is prohibited to prevent contamination of the installation environment by volatile release agent fumes. For molds used for the first time or cleaned with a cleaning agent, apply five coats of release agent; after each subsequent demolding, apply three coats. Allow at least 15 minutes between each coat, and wait at least 30 minutes after the last coat before proceeding to the next step. If molds that have undergone release agent application are placed outside the installation area, cover their surfaces with a thin film to prevent dust contamination.

[0035] As an alternative to applying release agents, operators can also choose to use fluorinated release cloth with adhesive backing to ensure effective release. Fluorinated release cloth has excellent non-stick properties, effectively preventing the composite material from sticking to the mold.

[0036] III. Specific Implementation Methods for Pre-laying Inspection Steps Pre-installation inspection is a crucial step in ensuring that the installation environment, equipment, and raw materials meet the process requirements.

[0037] Regarding environmental checks, operators inspect the ambient temperature and humidity in the installation area. Using calibrated thermometers and hygrometers, measurements are taken to confirm that the temperature is within the range of 22±4℃ and the humidity does not exceed 60%, and the results are recorded in the process log. Temperature and humidity control has a significant impact on the tackiness of the prepreg—excessive temperature leads to a decrease in resin viscosity and prepreg collapse and deformation; excessively low temperature results in insufficient tackiness and poor interlayer bonding; excessive humidity causes moisture to condense on the prepreg surface, affecting the resin curing reaction and interfacial bonding quality.

[0038] Regarding the inspection of measuring instruments, operators check whether the measuring instruments used meet the availability requirements and are within their calibration validity period. For example, thermometers and hygrometers used to measure temperature and humidity, vacuum gauges used to measure vacuum, and measuring instruments used to measure dimensions must all be within their valid calibration period.

[0039] Regarding raw material inspection, operators reconfirm whether the remaining operating life and mechanical performance life of the raw materials meet the requirements to ensure that the materials maintain sufficient operating performance before the installation process is completed.

[0040] Regarding the inspection of mold components, operators confirm whether the mold information is correct and whether the bolts, movable parts and other components are complete, to ensure that the mold can be used normally in subsequent processes.

[0041] IV. Detailed Implementation Methods of the Laying Steps The laying process is a core step in the forming of furnace-mounted parts, and its operational quality directly affects the internal quality and mechanical properties of the furnace-mounted parts.

[0042] The forming process of the furnace-fed parts should be as consistent as possible with that of the product, including the layup sequence, layup direction, and pre-compaction operations. This ensures that the process history of the furnace-fed parts is the same as that of the product, thus making the performance characterization results of the furnace-fed parts representative.

[0043] Operators lay prepreg layer by layer on the mold according to the layup schedule. The layup schedule is a detailed record of the layup order and direction specified in the process documents. Operators must strictly follow the order and angle of the layup schedule and must not change it arbitrarily.

[0044] After each layer of prepreg is laid, the operator needs to visually check whether the fiber orientation matches the angle within the layup surface. For unidirectional prepreg, the fiber orientation is identified by the fiber arrangement direction; for woven prepreg, the fiber orientation is identified by the warp and weft directions. If the fiber orientation deviation is found to exceed the allowable range, the position of the prepreg sheet must be adjusted promptly.

[0045] To remove air bubbles and smooth out wrinkles, operators use a scraper in conjunction with a blower for added heat to remove air bubbles and smooth out wrinkles generated during the laying process, following the fiber direction. During operation, the scraper is held at an angle to the surface, applying appropriate pressure and pushing evenly from the center of the sheet towards the edges, allowing interlayer gas to escape along the fiber direction. The blower provides appropriate heat to reduce resin viscosity and increase the layability of the prepreg, but the heating temperature should not be too high to avoid premature resin curing. Operators use scissors and a utility knife to remove excess prepreg outside the laying area, ensuring neat edges on the sheet.

[0046] During the installation process, the backing release paper and release film should be retained. These materials are protective layers inherent to the prepreg; retaining them prevents contamination from direct contact between fingers and the prepreg during installation and facilitates subsequent layer counting and confirmation. After installation, operators should count and verify the quantity of all used release paper and release film to confirm that the actual number of layers matches the layup requirements, ensuring no inclusions or foreign objects are present.

[0047] For vacuum pre-compaction, vacuum pre-compaction is performed according to the layer sequence required in the layup table. Operators use vacuum pre-compaction auxiliary materials to assemble vacuum bags, encapsulate the molds containing the completed partial layups within the vacuum bags, connect the vacuum lines, and turn on the vacuum pump. The vacuum level required for vacuum pre-compaction is -100 kPa to -80 kPa, maintained for at least 15 minutes. The purpose of pre-compaction is to expel air from between the laid layers, compact the layup, and prevent air bubbles from accumulating between layers during subsequent laying.

[0048] After the final layer is laid, the operator assembles vacuum bags using vacuum compaction auxiliary materials according to the sealing procedure. The vacuum bags should have evenly and symmetrically arranged pleats. The required compaction vacuum level is -100KPa to -85KPa, and should be maintained for no less than 1 hour. The purpose of this vacuum compaction is to finally compact all layers before curing, ensuring tight bonding between layers and expelling residual gas.

[0049] V. Specific Implementation Methods of the Packaging Steps The encapsulation step involves sealing the completed and final compacted components and auxiliary materials together in a vacuum bag to provide a vacuum environment for curing.

[0050] First, the operator places the parts labels as required, with the labels indicating the part name, drawing number, and placement date, to facilitate subsequent traceability.

[0051] Next, the operator places the equalizing plate. The equalizing plate is slightly smaller than the sheet size and should be centered. The equalizing plate is made of a material compatible with the curing temperature and is cured together with the sheet inside the vacuum bag. The function of the equalizing plate is to evenly transfer the vacuum pressure to the surface of the sheet during the curing process, preventing localized pressure concentration or insufficient pressure caused by wrinkles or uneven shrinkage of the vacuum bag.

[0052] In vacuum bag manufacturing, operators use a vacuum curing auxiliary material kit for sealing. Specifically, a release liner is placed over the material sheet, followed by a non-porous release film and a breathable felt, and finally the vacuum bag film. The vacuum bag film is cut to size according to the mold dimensions, ensuring complete coverage of the product and mold edges, with allowance for pleating to ensure uniform shrinkage during vacuuming without excessive stretching or tearing. Sealing strips are used to seal the edges of the vacuum bag film to the mold surface, forming a closed vacuum system. Vacuum extraction points and thermocouples are placed for vacuuming and temperature monitoring.

[0053] For vacuum testing, after sealing, the operator turns on the vacuum pump to remove air from the vacuum bag membrane. Vacuuming is stopped when the pressure at all testing points reaches -100 kPa to -85 kPa. The vacuum decay value at all testing points must not exceed 5 kPa within 15 minutes. The vacuum decay value reflects the sealing performance of the vacuum bag system; excessive decay indicates a leak. If the decay value exceeds 5 kPa, the operator needs to check for leaks in the vacuum bag membrane, vacuum tubing, vacuum quick-connect suction cups, mold, etc. Troubleshooting methods include: carefully listening for leak sounds, applying soapy water to suspected areas to observe bubbles, and conducting segmented isolation checks. If a leak is found, it can be filled with yellow sealing strips, and the vacuum testing operation is repeated until the requirements are met.

[0054] VI. Specific Implementation Methods of the Curing Step The curing step is a key process that enables the resin in the prepreg to undergo a cross-linking reaction and obtain the final mechanical properties.

[0055] Before proceeding to the curing step, operators must confirm that the material's remaining operating life meets the requirements. For prepreg materials, before completing the application process, it must be ensured that the material's remaining operating life is greater than 0 hours to guarantee sufficient fluidity and tackiness of the resin during application; before turning on the heating equipment for curing, it must be ensured that the material's remaining mechanical property life is greater than 0 hours to guarantee that the cured mechanical properties meet the design requirements.

[0056] The operator then places the mold, after completing the above operations, into the autoclave. The autoclave is a key piece of equipment for the hot pressing and curing of composite materials, enabling the curing and molding of composite products under heat and pressure while a vacuum is applied.

[0057] Inside the autoclave, the operator connects the vacuum line and thermocouples. The vacuum line connects to the evacuation port of the vacuum bag to continuously evacuate during the curing process to maintain the vacuum level inside the bag; the thermocouples are used to monitor the temperature of the mold or sheet in real time, facilitating data collection and control later.

[0058] The vacuum test inside the autoclave is similar to the sealing process. Vacuuming should be stopped when the pressure at the vacuum test point reaches -100 kPa to -85 kPa. The vacuum level should not decrease by more than 5 kPa within 15 minutes. If the decrease exceeds 5 kPa, check for leaks in the vacuum bag film, vacuum tubing, vacuum quick-connect suction cups, mold, etc. If leaks are found, sealant strips can be used to fill the leaks, and the vacuum test should be repeated.

[0059] After completing the vacuum degree test, the operator sets the curing parameters. These parameters are determined according to the process specifications of the final product and generally include the heating rate (e.g., 1–3℃ / min), holding temperature (e.g., 120℃, 180℃, etc., determined according to different resin systems), holding time (e.g., 60–180 minutes), applied pressure (e.g., 0.4–0.7 MPa), and cooling rate. The operator inputs these parameters through the autoclave's control system and starts the curing program. The autoclave automatically completes the heating, pressurizing, holding, and cooling processes according to the set program.

[0060] VII. Specific Implementation Methods of the Demolding Step After the curing process is complete, operators wait for the product temperature to drop naturally to room temperature. Natural cooling helps reduce internal stress and deformation caused by temperature gradients, preventing warping or cracking of the parts during demolding.

[0061] After the product temperature drops to room temperature, the operator removes auxiliary materials from the surface of the parts, including vacuum bag film, breathable felt, non-porous release film, release cloth, and sealing strips. Care should be taken to remove these materials gently to avoid leaving any debris on the part surface. Thermocouples and vacuum connectors are removed, cleaned, and placed in designated locations for future use.

[0062] During the separation of parts from the mold, the operator gradually inserts a nylon release wedge along the gap between the part's edge and the mold, gently prying to separate the part from the mold. The nylon release wedge has a lower hardness than metal molds and composite material parts, effectively preventing scratches on the mold or part surface during demolding. Force should be applied gradually from multiple directions to avoid excessive force at a single point, which could cause localized cracking of the part.

[0063] After the parts are demolded, the operator cleans the mold surface of any residual adhesive. This residue mainly comes from resin overflowing from the edges of the prepreg and remnants of the sealing strip. A plastic scraper and cleaning agent are used to ensure the mold surface is clean and ready for the next use.

[0064] VIII. Specific Implementation Methods of the Inspection Steps Surface quality inspection is an important part of the inspection process, which uses visual inspection to determine whether there are surface defects in the furnace-loaded parts.

[0065] Operators conduct a comprehensive visual inspection of the parts under suitable lighting conditions. The inspection includes: resin-deficient areas – characterized by exposed fibers, a dry surface, or a whitish color, due to insufficient resin content in certain areas; defects such as fiber wrinkles, creases, cracks, or scratches that damage fibers – these defects affect the fiber's load-bearing capacity, reducing the part's strength and stiffness; the integrity of the release cloth – damage to the release cloth may cause direct contact between the breathable felt and the part's surface, resulting in surface contamination; dry spots or surface pores – dry spots refer to areas where resin has not fully impregnated the fibers, and surface pores refer to air bubbles or voids remaining on the surface after curing; resin-rich areas – characterized by resin buildup, abnormal surface gloss, or localized darker color; and areas of fiber deformation or twisting – areas where the fiber orientation deviates from design requirements. For any of the above defects found, operators use a white paint pen to mark the defect locations for subsequent quality assessment and recording.

[0066] After the appearance quality inspection is completed, the operator records the inspection results in the inspection record sheet as the raw data for the quality evaluation of the furnace-mounted parts.

[0067] The above embodiments are merely illustrative of the principles and effects of this application. Any person skilled in the art can modify or alter the above embodiments without departing from the purpose of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the purpose disclosed in this application should still be covered by the claims of this application.

Claims

1. A method for molding composite material test plates in a furnace, characterized in that, Includes the following steps: S1: Main material preparation: Take the prepreg material out of the frozen environment, check the storage expiration date, remaining operating life and remaining mechanical property life of the material, and ensure that the remaining operating life is >0h and the remaining mechanical property life is >0h; Thaw the material for no less than 8 hours. Thawing is considered complete when the outer packaging is wiped dry and no water droplets or moisture condense. S2: Mold preparation: Confirm that the material of the mold for the furnace parts is consistent with the material of the product mold, clean the mold surface, and apply release agent; S3: Pre-installation inspection: Check the ambient temperature, humidity, and the validity period of the measuring instruments; S4: Laying: Lay the prepreg layer by layer on the mold according to the layup schedule. After each layer of prepreg is laid, check whether the fiber direction is consistent with the angle in the layup schedule. Use a scraper and / or a blower to assist heating along the fiber direction to remove air bubbles and smooth out wrinkles. During the laying process, retain the backing release paper and release film. After laying, count and check to ensure that there are no foreign objects. Perform vacuum pre-compaction according to the layer sequence required in the layup schedule. The vacuum degree of vacuum pre-compaction is -100KPa to -80KPa, and the holding time is not less than 15 minutes. After the last layer is laid, perform vacuum compaction. The vacuum degree of vacuum compaction is -100KPa to -85KPa, and the holding time is not less than 1 hour. S5: Encapsulation: Place the pressure equalizing plate, use vacuum curing auxiliary material to assemble a vacuum bag for sealing, and perform vacuum degree testing. Stop vacuuming when the pressure value of all test points is -100KPa to -85KPa. It is required that the vacuum degree decay value of all test points is not greater than 5KPa within 15 minutes. S6: Curing: The encapsulated mold is placed into an autoclave, and the curing parameters are set for curing. S7: Demolding: After the product temperature naturally drops to room temperature, remove the auxiliary materials and separate the parts from the mold; S8: Inspection: Perform surface quality inspection on parts.

2. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In S1, the material is prepared using an automatic fabric cutting machine. When cutting the prepreg, the length edge of the roll is required to coincide with the 0° line of the machine. The fiber direction angle deviation is: ±2° for unidirectional prepreg and ±3° for woven prepreg. The allowable deviation of the material sheet size is ±2.5mm.

3. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S1, the cut material pieces are packaged with the part name and drawing number marked on them and then transferred to the installation station. If the installation is not planned to start within 48 hours, the cut material pieces are bagged and stored back in the freezer. They are then thawed before the installation process begins.

4. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S2, white cotton cloth, cleaning agent, plastic scraper and vacuum cleaner are used to clean dust and glue stains on the surface of mold and tooling; masking tape is used to isolate and protect the sealing strip area for bag making.

5. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S2, the mold is first used or cleaned with a cleaning agent and then coated with release agent 5 times. After each part is demolded, release agent is applied 3 times. The interval between each release agent application is at least 15 minutes. The next process is carried out at least 30 minutes after the last release agent application is completed.

6. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S2, the alternative to applying a release agent is to use an adhesive-backed fluorinated release cloth to ensure the release effect.

7. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In S3, the ambient temperature is 22±4℃ and the ambient humidity is ≤60%.

8. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In S4, the forming process of the furnace-fed parts is kept as consistent as possible with the product.

9. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S4, the vacuum precompaction is performed using a vacuum precompaction auxiliary material group to make a vacuum bag. The vacuum precompaction auxiliary material group includes a porous isolation membrane, a release cloth, a breathable felt, and a vacuum bag film.

10. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S5, the vacuum curing auxiliary material group includes a release cloth, a non-porous isolation membrane, a breathable felt, and a vacuum bag film.

11. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S5, the pressure equalizing plate is slightly smaller than the material sheet and is placed in the center. The pressure equalizing plate is cured together with the material sheet inside the vacuum bag. The vacuum bag has pleats evenly and symmetrically arranged.

12. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S6, the remaining working life of the material is ensured to be >0h before the laying process is completed; the remaining mechanical property life of the material is ensured to be >0h before the heating equipment is turned on for curing.

13. The method for forming composite material test plates in a furnace according to claim 1, characterized in that, In step S7, a nylon release wedge is gradually inserted along the gap between the edge of the part and the mold, and gently pried to separate the part from the mold.

14. A method for forming parts in a furnace, characterized in that, Includes the following steps: S9: Select the type of furnace-fed component, which includes pure fabric furnace-fed component, unidirectional belt furnace-fed component, and sandwich furnace-fed component; S10: Determine the layup scheme according to the selected furnace component type: fabric furnace component layup is 0 / 90°n, unidirectional belt furnace component layup is 0°n, and sandwich furnace component layup is 45° / 0° / PMI / 0° / 45°. S11: The furnace-mounted component is formed using the method steps described in any one of claims 1 to 13.

15. The furnace-fed component forming method according to claim 14, characterized in that, The core component used in the furnace is a 5mm foam core.

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