Quartz fiber reinforced PEEK resin-based wave-transparent composite material and forming method

Abstract

The invention relates to a quartz fiber reinforced PEEK resin-based wave-transparent composite material and a forming method thereof, and the forming method comprises the following steps: uniformly coating a layer of PEEK resin powder on quartz fiber cloth, repeatedly laying the quartz fiber cloth and the PEEK resin powder in a laminated manner, arranging quartz fibers on the uppermost layer to finish laying, and compacting to obtain a preformed blank; carrying out compression molding on the preformed blank: heating to 280-320 DEG C from room temperature, carrying out first-stage heat preservation, pressurizing after the first-stage heat preservation is finished, and carrying out first pressure maintaining treatment; the temperature is increased to 390-410 DEG C, second-stage heat preservation is carried out, pressurization is carried out after second-stage heat preservation is finished, and second pressure maintaining treatment is carried out; and heating to 420-435 DEG C, carrying out third-stage heat preservation, and after the third-stage heat preservation is finished, pressurizing and exhausting to obtain the composite material. According to the invention, one-time layering is combined with multi-section heating and other operations to realize blank compression molding, and the obtained composite material is good in interlayer combination and has good mechanical properties and wave-transparent properties.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wave-transparent materials, in particular to a quartz fiber reinforced PEEK resin-based wave-transparent composite material and a forming method. BACKGROUND

[0002] Polyether ether ketone (PEEK) resin as a kind of thermoplastic engineering plastic, due to its good high temperature resistance, wave-transparency, chemical stability, impact resistance, wear resistance, excellent electrical properties and other characteristics, in aerospace, electronics, medical, mechanical and other fields have been widely used. The traditional PEEK resin is produced by extrusion granulation, and then injection molding. But due to the high melting point, high hardness, difficult to dissolve and other characteristics, the screw usually needs to be disassembled and calcined at high temperature after each production to clean the screw, which is difficult to clean and easy to damage the screw.

[0003] Mold pressing as a kind of material in the mold by pressure, temperature effect production products forming method, because of its simple operation, mold cleaning convenient and other factors have been widely used. The conventional temperature limit of the heating method of the tooling used in traditional mold pressing is 200℃. But because the melting point of PEEK resin is between 330℃-387℃, which puts higher requirements on the temperature characteristics of the forming tooling.

[0004] At the same time, in order to make PEEK resin obtain higher mechanical properties, usually take carbon fiber or glass fiber to reinforce it. However, the mechanical properties of fiber reinforced resin matrix composite material depend largely on the wettability between resin and fiber. Therefore, in the process of preparing composite material, how to improve the interfacial strength by modifying the fiber and resin, fully play the advantages of both, further improve its mechanical properties has been the focus of research in the field of composite materials. SUMMARY

[0005] The purpose of the present application is to overcome the above technical deficiencies, provide a quartz fiber reinforced PEEK resin-based wave-transparent composite material and a forming method, solve the technical problems of PEEK resin-based wave-transparent material forming and reinforcement in the prior art.

[0006] In order to achieve the above technical purpose, the technical scheme provided by the present application is: In a first aspect, the present application provides a molding method of a quartz fiber reinforced PEEK resin-based wave-transparent composite material, comprising the following steps: S1, uniformly coating a layer of PEEK resin powder on a quartz fiber cloth, then repeatedly laying the quartz fiber cloth and the PEEK resin powder, and laying the quartz fiber cloth in the uppermost layer to end the laying, and compacting to obtain a preform; S2, molding the preform: heating from room temperature to 280-320℃ for a first holding, then pressurizing and performing a first pressure holding after the first holding; then heating to 390-410℃ for a second holding, then pressurizing and performing a second pressure holding after the second holding; then heating to 420-435℃ for a third holding, then pressurizing and exhausting after the third holding, to obtain the quartz fiber reinforced PEEK resin-based wave-transparent composite material.

[0007] In a second aspect, the present application provides the quartz fiber reinforced PEEK resin-based wave-transparent composite material obtained by the above molding method.

[0008] Compared with the prior art, the present application has the following beneficial effects: The present application realizes the molding of the preform by one-time laying and combining with multi-stage heating and stage-by-stage pressurizing, solves the difficulty in molding and reinforcing of the PEEK resin-based composite material, and the obtained composite material has good interlayer bonding, good mechanical properties and wave-transparent properties, especially the molding temperature is controlled to make the resin fully infiltrate the surface of the fiber cloth and the internal bubbles are completely discharged, and the surface has no carbonization and blackening phenomenon, so that the obtained composite material has high molding quality, short preparation period and simple operation, and has good high-temperature resistance, mechanical properties and wave-transparent properties. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a differential scanning calorimetry analysis curve of PEEK resin; Figure 2 is a schematic view of a high-temperature molding mold structure of the present application; wherein, 1 - punch, 2 - recessed mold, 3 - preform, 4 - ejection device, 41 - ejection plate, 42 - ejector rod, 5 - electric heating tube, 6 - heat insulation plate. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0011] In view of the defects of PEEK resin-based wave-transparent material forming and reinforcement difficulty, the application provides a quartz fiber reinforced PEEK resin-based wave-transparent composite material and a forming method, a blank is prepared by using a multi-layer lamination mode of quartz fiber cloth and polyether ether ketone (PEEK) resin powder, then according to the temperature characteristics of the PEEK resin, the integrated mold pressing is carried out by using a multi-section type temperature rising and a stage progressive type pressure increasing, the obtained composite material has good interlayer bonding, good mechanical properties and wave-transparent performance, and the forming mode of the application is simple and can be used for large thickness blank production.

[0012] In the first aspect, the application provides a forming method of a quartz fiber reinforced PEEK resin-based wave-transparent composite material, including the following steps: S1, uniformly coating a layer of PEEK resin powder on the quartz fiber cloth, then repeatedly laminating and laying the quartz fiber cloth and the PEEK resin powder, and laying the quartz fiber cloth in the uppermost layer to end the lamination, and compacting to obtain a preformed blank; S2, mold pressing the preformed blank: from room temperature to 280-320 DEG C for one section of heat preservation, after the one section of heat preservation, pressure is added and the first pressure holding treatment is carried out; then heating to 390-410 DEG C for two sections of heat preservation, after the two sections of heat preservation, pressure is added and the second pressure holding treatment is carried out; then heating to 420-435 DEG C for three sections of heat preservation, after the three sections of heat preservation, pressure is added and exhaust is carried out, to obtain a quartz fiber reinforced PEEK resin-based wave-transparent composite material.

[0013] In view of the high melting point (see Figure 1 , 347 DEG C) of PEEK resin, the forming difficulty problem, the application realizes the mold pressing of the blank by controlling the temperature, pressure and other process parameters, solves the shortcomings of PEEK resin-based composite material forming and reinforcement difficulty, the obtained composite material has good interlayer bonding, good mechanical properties and wave-transparent performance, especially the control of the forming temperature, if the forming temperature is too high (above 440 DEG C), there is a phenomenon of partial carbonization and decomposition of the surface resin, the mold pressing blank is black in appearance, and the safety risk is high; if the forming temperature is too low (below 410 DEG C), the viscosity of the resin is high when finally solidified, the resin is difficult to fully infiltrate the surface of the fiber cloth when pressure is added, and the internal bubbles are difficult to completely discharge; thus the application obtains a composite material with good internal quality, high temperature resistance, high strength and other characteristics.

[0014] In addition, the Tg of PEEK resin is relatively high (147 DEG C), if the preheating is carried out in the middle of the lamination, the high temperature continues to laminate after preheating, there is a safety hazard, if the lamination is carried out after preheating and cooling, the production efficiency is low, and the finished product is prone to delamination, the application adopts the form of one-time lamination to avoid these defects, at the same time, the application adopts the form of multi-section type temperature rising and stage progressive type pressure increasing, there are pressure and pressure holding steps at 280-320 DEG C and 390-410 DEG C, which ensures uniform distribution of the resin.

[0015] Preferably, in step S1, the quartz fiber cloth is pre-dried by heating to 60-120°C at a rate of 1-5°C / min for 2-8 hours.

[0016] Preferably, in step S1, the thickness of the quartz fiber cloth is 0.1 to 0.4 mm; the quartz fiber cloth is type B quartz glass fiber cloth.

[0017] The size of the quartz fiber cloth used in this invention can be cut as needed. The cutting method can be mechanical cutting or manual cutting. The cutting size is preferably based on the size of the mold cavity of the molding die, with the size of the cavity to be filled flat.

[0018] Preferably, in step S1, the amount of PEEK resin powder used for single-layer laying is the same as the weight of a single-layer quartz fiber cloth.

[0019] Preferably, in step S1, the total number of layers of quartz fiber cloth and PEEK resin powder is 3 to 301.

[0020] Preferably, in step S1, compaction involves applying pressure to 35-40 MPa and maintaining it for 3-8 minutes, then depressurizing to obtain a preformed blank.

[0021] Preferably, in step S1, after holding the pressure, the pressure is released to a balanced pressure that prevents the thickness of the preformed blank from rebounding. This invention uses a small, accompanying balanced pressure (the balanced pressure is relatively small, all around 0.5 MPa) to counteract the internal expansion force of the preformed blank, ensuring that the thickness of the preformed blank does not rebound after pressure release.

[0022] Preferably, in step S2, the heat preservation time for one heat preservation period is 30 to 50 minutes.

[0023] Preferably, in step S2, the heat preservation time for the second stage of heat preservation is 30 to 50 minutes.

[0024] Preferably, in step S2, the heat preservation time for the three-stage heat preservation is 80 to 120 minutes.

[0025] Preferably, in step S2, the heating rate from room temperature to 280–320°C is 1.5–2.5°C / min.

[0026] Preferably, in step S2, the heating rate to 390–410°C is 1–1.2°C / min.

[0027] Preferably, in step S2, the heating rate to 420-435°C is 0.8-1.0°C / min.

[0028] Preferably, in step S2, the pressure in the first pressure holding process and the second pressure holding process is lower than the pressure of the pressurized exhaust.

[0029] Preferably, in step S2, the first pressure holding process is performed after applying pressure to the equilibrium pressure until the mold closing gap is 20-30mm, and the second pressure holding process is performed after applying pressure to the equilibrium pressure until the mold closing gap is 10-20mm; the pressure holding time is 3-8 minutes for both processes; after the first and second pressure holding processes are completed, the pressure is released to the equilibrium pressure (to counteract the internal expansion force of the billet and ensure that the billet thickness does not rebound after pressure release).

[0030] Preferably, in step S2, the pressurization and venting involves pressurizing to 70-75 MPa from the previous stage's equilibrium pressure and venting 3-5 times. It is understood that no pressure holding is required during the pressurization and venting stage; that is, pressurize to 70-75 MPa, immediately depressurize, pressurize and depressurize again, and repeat this process 3-5 times.

[0031] Preferably, in step S2, compression molding is performed in a high-temperature molding die, see [reference]. Figure 2 The high-temperature molding die includes a pair of punches 1 and dies 2, both of which have bases. The die 2 has a cavity for placing the preformed blank 3, and the bottom of the die 2 has an ejector device 4 for ejecting the composite material obtained by compression molding. The side walls of the die 2 and the punch 1 are equipped with heating tubes 5 for heating. The side walls of the die 2 and the punch 1 are equipped with heat insulation plates 6, and the heat insulation plates 6 are made of hot work die steel (H13). The heat insulation plates 6 are made of heat insulation material with a high temperature resistance of up to 500℃.

[0032] More preferably, the ejection device 4 includes an ejection plate 41 and an ejection rod 42 connected together.

[0033] Further preferred, the heating element is a high-temperature heating element XRN-DL-380V.

[0034] It is understood that the parts of the high-temperature molding die not described in detail in the specific structural connection of the present invention are all existing technologies, which can realize the main operations of molding (heating and pressurization). Based on the temperature characteristics of PEEK resin, the present invention takes into account the material, heating method and heat insulation. It mainly uses hot work die steel (H13) as the main material of the die, with the hardness tempered to above 35 HRC. It is equipped with a high-temperature electric heating tube (XRN-DL-380V) and high-temperature heat-resistant insulation material (the upper limit of the high temperature resistance needs to reach 500℃. There are many such materials on the market, so no specific limit is made here. It is sufficient to significantly improve the temperature limit of commonly used heat insulation materials of 300℃). This gives it excellent high-temperature resistance and can meet the molding requirements of PEEK resin-based composite materials.

[0035] Secondly, the present invention provides a quartz fiber reinforced PEEK resin-based wave-transparent composite material obtained by the above molding method.

[0036] The main advantages of this invention are: (1) The high-temperature molding die used not only has good temperature characteristics in the high-temperature region, which can meet the molding of high-melting-point PEEK resin-based composite materials, but also has good temperature characteristics in the low-temperature region, which can be used for molding of phenolic resin-based and other composite materials.

[0037] (2) Fiber-reinforced braided layup is selected and integral molding is adopted. The fiber volume content of the resulting composite material is adjustable, and the fiber strength utilization rate can be fully controlled.

[0038] (3) With PEEK resin as the matrix, the composite material has good high temperature resistance. By controlling the fiber volume content, the blank has good mechanical properties and wave transmission properties.

[0039] (4) This molding method can be used to produce thick blanks, and the interlayer bonding of the reinforcing body is good, and the molding method is simple.

[0040] The present invention will be further described in detail below through specific embodiments. The target flat blank has dimensions of 250mm × 250mm × 40mm, where 40mm is the thickness. The quartz fiber cloth used is type B quartz glass fiber cloth, cut into 0.28mm × 248mm × 248mm sizes using scissors or a utility knife, in a quantity of 150 sheets. The cut type B quartz glass fiber cloth is then placed in an oven and dried at 1℃ / min-5℃ / min until the oven reaches 100℃ for 2-3 hours. After drying, it is packaged in clean plastic bags and is intended for use within two days.

[0041] Example 1 A molding method for a quartz fiber reinforced PEEK resin-based microwave-transparent composite material includes the following steps: S1. Clean the mold cavity surface with alcohol and a clean cotton cloth. Open the mold cavity and evenly spray a release agent inside. Lay a single layer of quartz fiber cloth into the mold cavity, then evenly coat a layer of PEEK resin powder onto the quartz fiber cloth. Repeat this filling process, one layer of fiber cloth + one layer of resin powder, for a total of 140 layers of cloth + 139 layers of resin powder (quartz fiber is placed on the top layer to finish the layup), to obtain a preformed blank, and then close the mold. Each layer of resin powder weighs 17g (the same as the weight of a single piece of fiber cloth). After the layup is completed, apply pressure of 38MPa, stabilize this pressure for 5 minutes, then release the pressure and stabilize it to an equilibrium pressure of 0.5MPa.

[0042] S2, Compression molding of the preformed blank: S201, one-stage heating, heat preservation and pressurization: at a heating rate of 2℃ / min, the temperature is raised from room temperature to 300℃ and held for 40min. After the heat preservation is completed, the pressure is increased from 0.5MPa. When the mold closing gap is controlled at 20-30mm, the pressure is stabilized for 5min and then released to 0.5MPa. S202, two-stage heating, holding, and pressurization: The temperature is then increased to 400℃ at a rate of 1℃ / min and held for 40min. After the holding period, the pressure is increased from 0.5MPa. When the mold closing gap is controlled at 10-20mm, the pressure is stabilized for 5min and then released to 0.5MPa. S203, three-stage heating, holding, and pressurization: The temperature is then increased to 430℃ at a heating rate of 0.8℃ / min and held for 100min. After the holding period, the pressure is increased to 72 MPa and the pressure is released three times; the power is disconnected, and the mold temperature is allowed to drop naturally to below 60℃, with the pressure naturally released from the cooling process; the mold is then demolded, and dimensional processing is performed to obtain the composite material.

[0043] Example 2 Compared with Example 1, the only difference is that after the layup is completed in step S1, the pressure is increased to 35 MPa, and the other steps and conditions are the same as in Example 1.

[0044] Example 3 Compared with Example 1, the only difference is that after the layup is completed in step S1, the pressure is increased to 40 MPa, and the other steps and conditions are the same as in Example 1.

[0045] In Examples 1-3, the holding pressure after the layup was changed within a certain range, which facilitated production operations and had virtually no impact on product performance.

[0046] Comparative Example 1 Compared with Example 1, the only difference is that the heat preservation temperature in step S203 is set to 400°C, while the other steps and conditions are the same as in Example 1.

[0047] The results showed that when the molding temperature was too low, the resin viscosity was high when it was finally cured. Under pressure, the resin could not fully wet the surface of the fiber cloth, and the internal air bubbles could not be completely expelled, resulting in poor interlayer bonding and decreased mechanical properties of the composite material.

[0048] Comparative Example 2 Compared with Example 1, the only difference is that the heat preservation temperature in step S203 is set to 450°C, while the other steps and conditions are the same as in Example 1.

[0049] The results showed that when the molding temperature was too high, the surface resin underwent partial carbonization and decomposition, resulting in a blackened appearance on the molded blank.

[0050] Comparative Example 3 Compared with Example 1, the only difference is that: in step S2, the compression molding does not use segmented heat preservation, steps S201-202 are removed, and the preformed blank is directly processed in step S203. Other steps and conditions are the same as in Example 1.

[0051] The results showed that when the temperature was increased to the pressure exhaust temperature in one step, the heat conduction inside the billet lagged behind that of the mold. When the pressure exhaust was applied, the internal temperature of the billet was lower than the theoretical temperature. When the pressure was applied, the resin could not fully wet the surface of the fiber cloth, and the internal air bubbles could not be completely discharged, resulting in poor interlayer bonding of the composite material and a decrease in mechanical properties.

[0052] Comparative Example 4 Compared with Example 1, the only difference is that in step S203, heat preservation and pressurization are carried out simultaneously, while other steps and conditions are the same as in Example 1.

[0053] The results showed that when the pressure was applied prematurely and the resin viscosity was high, the resin could not fully impregnate the fiber, resulting in air bubbles inside the preform.

[0054] Comparative Example 5 Compared with Example 1, the only difference is that in step S1, the amount of resin powder used per layer is 13g, and the other steps and conditions are the same as in Example 1.

[0055] The results showed that a high fiber volume content resulted in relatively good mechanical properties and wave transmission properties of the preform, but the density also increased, which could not meet the requirements for lightweight aerospace materials.

[0056] Comparative Example 6 Compared with Example 1, the only difference is that in step S1, the amount of resin powder used per layer is 21g, and the other steps and conditions are the same as in Example 1.

[0057] The results showed that the fiber volume content was low and the preform density was low, but the mechanical properties and wave transmission properties were significantly reduced.

[0058] Performance testing The obtained composite material was subjected to specific performance tests, and the specific reference standards were as follows: tensile properties were tested according to GB / T1447-2005 (room temperature); density was tested according to GB / T1463-2005 (room temperature); thermal weight loss (550℃ / 40s) was tested according to GJB1873; thermal conductivity (300℃) was tested according to GB / T10295-2008; dielectric constant and loss tangent were tested according to the high-Q cavity method (test frequency: 7GHz~18GHz); the results are shown in Table 1 below.

[0059] Table 1. Test results of the composite materials obtained in each embodiment and comparative example.

[0060] Among them, the smaller the dielectric constant and the smaller the loss tangent, the better the wave transmission performance.

[0061] As shown in Table 1, when the molding temperature is low (Comparative Example 1), the fiber resin has poor wettability and low mechanical strength. When the molding temperature is too high (Comparative Example 2), the resin decomposes due to overheating, resulting in reduced mechanical strength and reduced heat resistance.

[0062] As can be seen from Example 1 and Comparative Examples 3-4, segmented insulation and pressurization after insulation are beneficial for the fibers to be fully impregnated with resin, improve the interfacial bonding strength, and improve the mechanical strength.

[0063] When the fiber volume content is high (Comparative Example 5), the product's wave transmission performance and mechanical strength increase, but the density is high; when the fiber volume content is low (Comparative Example 6), the product density decreases, but the wave transmission performance and mechanical strength decrease; while in Example 1, the fiber / resin ratio is set to 1:1, which can ensure that the fiber volume content is controlled at a certain value, which is beneficial to controlling the blank density, improving the material strength, and also beneficial to its good wave transmission performance.

[0064] Therefore, when the fiber volume content is appropriate, the molding temperature is appropriate, the staged heating and heat preservation is appropriate, and the timing of pressurization is appropriate, the resulting composite material has good wave transmission performance, mechanical strength and heat resistance.

[0065] Therefore, this invention achieves blank forming by controlling process parameters such as fiber volume content, temperature, and pressure. The resulting composite material has high forming quality, strong mechanical properties, good high temperature resistance, excellent wave transmission performance, short preparation cycle, and simple operation.

[0066] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A molding method for a quartz fiber reinforced PEEK resin-based microwave-transparent composite material, characterized in that, Includes the following steps: S1, uniformly coat a layer of PEEK resin powder on the quartz fiber cloth, then repeatedly lay the quartz fiber cloth and PEEK resin powder in layers, and finish the layup by arranging the quartz fiber on the top layer and compacting it to obtain the preform blank. S2, the preformed blank is molded: the temperature is raised from room temperature to 280-320°C for a first heat preservation, after the first heat preservation is completed, pressure is applied and a first pressure preservation treatment is performed; then the temperature is raised to 390-410°C for a second heat preservation, after the second heat preservation is completed, pressure is applied and a second pressure preservation treatment is performed. The temperature is then raised to 420-435℃ for three-stage heat preservation. After the three-stage heat preservation is completed, the pressure is increased and the air is exhausted to obtain a quartz fiber reinforced PEEK resin-based wave-transparent composite material.

2. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S1, the quartz fiber cloth is pre-dried by heating to 60-120°C at a rate of 1-5°C / min for 2-8 hours. The thickness of the quartz fiber cloth is 0.1 to 0.4 mm; the quartz fiber cloth is type B quartz glass fiber cloth.

3. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S1, the amount of PEEK resin powder used for single-layer laying is the same as the weight of a single-layer quartz fiber cloth.

4. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S1, the total number of layers of quartz fiber cloth and PEEK resin powder is 3 to 301. The compaction process involves applying pressure to 35–40 MPa and maintaining it for 3–8 minutes, then releasing the pressure to the equilibrium pressure to obtain a preformed blank.

5. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S2, the heat preservation time of the heat preservation section is 30-50 minutes; The heat preservation time for the two-stage heat preservation is 30 to 50 minutes; The insulation time for the three-stage insulation is 80–120 minutes.

6. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S2, the heating rate from room temperature to 280-320°C is 1.5-2.5°C / min; The heating rate to 390–410°C is 1–1.2°C / min; The heating rate to 420–435°C is 0.8–1.0°C / min.

7. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S2, the pressure in the first and second pressure holding processes is lower than the pressure of the pressurized exhaust. The first pressure holding process involves applying pressure to the equilibrium pressure until the mold closing gap is 20-30 mm and then holding the pressure; the second pressure holding process involves applying pressure to the equilibrium pressure until the mold closing gap is 10-20 mm and then holding the pressure; the holding time for both processes is 3-8 minutes; after the first and second pressure holding processes are completed, the pressure is released back to the equilibrium pressure.

8. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S2, the pressurized exhaust is performed by pressurizing to 70-75 MPa and exhausting 3-5 times.

9. The molding method of the quartz fiber reinforced PEEK resin-based microwave-transparent composite material according to claim 1, characterized in that, In step S2, the compression molding is performed in a high-temperature compression mold, which includes a paired punch and a die, both of which have a base. The die cavity is provided with a cavity for placing the preformed blank, and the bottom of the die cavity is provided with an ejector device for ejecting the composite material obtained by compression molding. Heating tubes for heating are installed inside the sidewalls of the concave die and the convex die; Heat insulation plates are provided on the outer sidewalls of the die and the punch, as well as between them and their respective bases; the die and the punch are made of hot work die steel, and the heat insulation plates are made of heat insulation material with a maximum temperature resistance of 500℃.

10. The quartz fiber reinforced PEEK resin-based microwave-transparent composite material obtained by the molding method according to any one of claims 1-9.

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