A continuous fiber-reinforced composite honeycomb panel and a method for manufacturing the same

Abstract

The application discloses a kind of based on continuous fiber reinforced composite honeycomb plate and preparation method thereof, it is related to composite sheet technical field, including honeycomb core layer, gradient reinforcement layer and interface transition layer, the honeycomb core layer is set to modified thermoplastic honeycomb structure, the interface transition layer is connected to the outer wall both sides of honeycomb core layer, the interface transition layer outer wall side surface is combined gradient reinforcement layer, the gradient reinforcement layer is made of continuous basalt fiber prepreg and thermoplastic resin composite, and the fiber of the thermoplastic resin is multi-axial orientation distribution along the thickness direction.The interface transition layer of the application realizes excellent interface combination and mechanical property gradient transmission function, solves the problem of insufficient interlaminar bonding force and discontinuous mechanical property of traditional honeycomb plate, improves the overall strength, stiffness and delamination resistance of composite honeycomb plate.

Description

Technical Field

[0001] This invention relates to the field of composite panel technology, specifically to a composite honeycomb panel based on continuous fiber reinforcement and its preparation method. Background Technology

[0002] Composite honeycomb panels, as a core category of lightweight structural materials, demonstrate irreplaceable application value in aerospace, high-speed transportation, and building energy conservation fields due to the biomimetic mechanical structure of the honeycomb core layer and the synergistic load-bearing characteristics of the surface material. Continuous fiber reinforced composite honeycomb panels, through the directional arrangement of high-performance fibers such as carbon fiber and glass fiber, can increase the structural specific strength to 3-5 times that of traditional aluminum alloys, making them a key material for weight reduction in aircraft and lightweighting of new energy equipment. However, existing technologies still face significant bottlenecks in material design, manufacturing processes, and environmental adaptability.

[0003] Patent CN106926516B discloses a composite honeycomb sandwich panel and its preparation method. The above patent avoids the use of additional solvent-based adhesives, thus being more environmentally friendly. At the same time, it improves the bonding strength between the aluminum honeycomb core and the epoxy resin reinforcing material surface layer, making the composite honeycomb sandwich panel less prone to delamination.

[0004] The aforementioned patent effectively improves environmental friendliness by avoiding the use of additional solvent-based adhesives, while enhancing the bonding strength between the aluminum honeycomb sandwich core and the epoxy resin reinforcing material surface layer, significantly reducing the risk of delamination of the composite honeycomb sandwich panel. However, traditional epoxy resin base surface layers have limitations in heat resistance, and the in-plane anisotropy of the material may lead to uneven distribution of mechanical properties.

[0005] Therefore, this application proposes a composite honeycomb panel based on continuous fiber reinforcement, which can achieve performance integrity enhancement by introducing continuous basalt fiber multiaxial orientation prepreg and gradient distribution of silicon carbide whiskers, and its preparation method. Summary of the Invention

[0006] The purpose of this invention is to provide a composite honeycomb panel based on continuous fiber reinforcement and its preparation method, so as to solve the technical problems mentioned in the background art, such as uneven distribution of mechanical properties of composite panels, rapid expansion of damage after impact damage, difficulty in in-situ repair, reliance on manual inspection and replacement, and increased maintenance costs.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a composite honeycomb panel based on continuous fiber reinforcement, comprising a honeycomb core layer, a gradient reinforcement layer, and an interface transition layer, wherein the honeycomb core layer is configured as a modified thermoplastic honeycomb structure, the interface transition layer is connected to both sides of the outer wall of the honeycomb core layer, the gradient reinforcement layer is combined with the outer side of the interface transition layer, and the gradient reinforcement layer is composed of continuous basalt fiber prepreg and thermoplastic resin, wherein the fibers of the thermoplastic resin are multiaxially oriented along the thickness direction;

[0008] The interface transition layer is a nanoparticle-modified polymer film with a thickness of 50-150 μm, a nanoparticle size of 20-80 nm, and a mass percentage of 5%-15%.

[0009] Preferably, the honeycomb core material is polyphenylene sulfide, the honeycomb core has a hexagonal mesh structure, a wall thickness of 0.08-0.15 mm, a side length of 3-5 mm, and the surface is formed by plasma etching to form a micron-level pit array with a pit depth of 5-20 μm and a density of 100-300 pits / mm². 2 .

[0010] Preferably, the plasma etching setting power is 100-300W, the processing time is 30-90s, the gas composition is argon and oxygen, the volume ratio of argon to oxygen is 5:1-3:1, the surface roughness Ra after etching is 1.5-3.0μm, and the contact angle is 40°-60°.

[0011] Preferably, the basalt fiber has a fiber volume fraction of 55%-65%, a layup angle of 0° / ±45° / 90° alternating, a single layer thickness of 0.1-0.25mm, and a total number of layers ≥4;

[0012] Basalt fibers are first impregnated with a 5-10 g / L silane coupling agent aqueous solution for 1-3 min and then dried at 120-150℃ for 30-60 min. After treatment, the hydroxyl content on the fiber surface is 20%-40% of that before treatment.

[0013] Preferably, the nanoparticle-modified polymer film has a dispersion of ≤2.5, the nanoparticles are nano-alumina, the modified polymer is modified epoxy resin, the epoxy resin is bisphenol A type epoxy resin, the curing agent is a latent imidazole compound, and the glass transition temperature after curing is ≥180℃.

[0014] The interface transition layer also contains 0.5-3 wt% silicon carbide whiskers with an aspect ratio >50:1, which are distributed in a gradient along the thickness direction. The whisker content is C on the side near the honeycomb core layer and C+ΔC on the side near the gradient reinforcement layer, with ΔC / C = 20%-40%. The whisker surface is modified with KH-560 silane coupling agent, and the grafting rate is ≥90%.

[0015] Preferably, the gradient reinforcement layer is embedded with a shape memory alloy wire mesh, the alloy composition is Ni-Ti-Cu, the atomic ratio of Ni-Ti-Cu is 50:45:5, the wire diameter is 0.05-0.1mm, the mesh spacing is 2-5mm, the wire mesh pre-deformation amount is 5%-10%, the pre-deformation temperature is 80-120℃, the complete recovery temperature is 150-180℃, the recovery force is ≥50MPa, the surface of the shape memory alloy wire mesh is coated with a nickel-phosphorus alloy layer with a thickness of 1-3μm, the surface resistance is ≤0.5Ω / cm, and the interfacial bonding strength with thermoplastic resin is ≥40MPa;

[0016] The surface of the gradient enhancement layer is laser-etched with microtextures, which include intersecting grooves with a depth of 20-50 μm, a groove width of 0.1-0.3 mm, an included angle of 60°-120°, a coverage of 30%-60%, a microtexture edge radius of ≤5 μm, and a surface roughness Ra≤2.0 μm.

[0017] Preferably, the thermoplastic resin is polyetheretherketone (PEEK), with a melt index of 10-25 g / 10 min, a glass transition temperature of 143 °C, and a crystallinity of 35%-50%.

[0018] A conductive shielding layer is provided between the honeycomb core layer and the gradient reinforcement layer. The conductive shielding layer is composed of silver-plated glass fiber cloth and graphene-modified polyurethane. The silver-plated glass fiber cloth has a fiber diameter of 5-10 μm, a silver plating layer thickness of 0.2-0.5 μm, a graphene mass ratio of 2%-5%, an average sheet thickness of 1-3 nm, a sheet resistance of ≤1 Ω / sq, and a thickness of 0.05-0.2 mm. A titanium nitride coating with a thickness of 0.5-2 μm is deposited on the surface of the conductive shielding layer by magnetron sputtering.

[0019] Preferably, the hexagonal honeycomb wall of the honeycomb core layer is provided with carbon fiber-polyphenylene sulfide composite fibers with a diameter of 5-8 μm, distributed along the axial direction of the honeycomb wall, and a density of 5-10 fibers / mm.

[0020] Preferably, the preparation method includes the following steps:

[0021] S1. Modified polyphenylene sulfide particles are extruded to prepare honeycomb core blanks. The blanks are stretched into hexagonal honeycomb structures by a traction machine and cut into core plates with a thickness of 10-50mm. Then, the surfaces on both sides of the core plates are treated with plasma etching equipment with a power of 100-300W and a time of 30-90s. The gas flow ratio Ar:O2 = 5:1-3:1.

[0022] S2. Basalt fiber bundles are activated by plasma treatment, and then coated with polyphenylene sulfide resin by melt impregnation method. The impregnation temperature is 380-420℃ and the traction rate is 0.3-1.2m / min to form a prepreg tape with a single layer thickness of 0.1-0.25mm. The prepreg tapes are then stacked in the order of 0° / ±45° / 90°, with 4-8 layers.

[0023] S3. Mix nano-alumina with a particle size of 20-80nm with epoxy resin, curing agent and silicon carbide whiskers, and ultrasonically disperse for 30-60min to obtain an adhesive solution. Then, apply the adhesive solution to the surface of the honeycomb core layer and the bottom surface of the prepreg tape by electrostatic spraying. The spraying voltage is 30-50kV and the coating thickness is controlled at 50-150μm. After coating, cure at 80℃ for 2h, and then raise the temperature to 120℃ for 1h.

[0024] S4. The honeycomb core layer coated with the interface transition layer is stacked with the prepreg tape and placed in a vacuum hot press for pulse hot pressing:

[0025] First stage: Pressure 0.5-1MPa, temperature 200-230℃, maintain for 30 minutes, and remove air;

[0026] Second stage: Pressure 2-3MPa, temperature 360-380℃, hold for 60min, resin melt composite;

[0027] S5. After cooling to room temperature, demold, cut to size, and then perform surface hardening by magnetron sputtering deposition of titanium nitride coating.

[0028] Preferably, the preparation method further includes the following steps:

[0029] S31. The silicon carbide whiskers of the adhesive solution are dispersed by gradient centrifugation, with the rotation speed gradually increasing from 500 rpm to 3000 rpm at 10 min intervals, so that the whiskers form a concentration gradient along the vertical direction.

[0030] S32. Mix polyphenylene sulfide particles with 5-15wt% short-cut carbon fibers and 3-8wt% nano boron nitride, melt blend in a twin-screw extruder at 320-360℃, and then extrude and granulate.

[0031] S41. The heating rate of pulse hot pressing is 5-10℃ / min, the cooling rate is ≤8℃ / min, the vacuum degree is ≤10Pa, tensile stress is applied at 80-120℃, and after holding for 10-30min, it is water-cooled for shaping, and pre-deformed shape memory alloy wire mesh is used.

[0032] S42. Before proceeding to S4, lay silver-plated glass fiber cloth and graphene polyurethane film on the surface of the honeycomb core layer to set a conductive shielding layer.

[0033] S43. Urea-formaldehyde resin shell microcapsules were prepared by in-situ polymerization. The core material was dicyclopentadiene and Grubb catalyst in a mass ratio of 100:1. The capsule diameter was 50-200 μm and the shell thickness was 5-10 μm.

[0034] Microcapsules are evenly spread during the prepreg tape stacking process, with a density of 10. 4 -10 5 pcs / m 2 ;

[0035] When the microcapsules rupture due to damage to the board, holding the temperature at 60-80℃ for 30-60 minutes causes dicyclopentadiene to undergo a ring-opening metathesis polymerization reaction, thus repairing the cracks.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] 1. This invention achieves excellent interfacial bonding and mechanical property gradient transfer through an interface transition layer, solving the problems of insufficient interlayer bonding and discontinuous mechanical properties in traditional honeycomb panels, and improving the overall strength, stiffness and anti-delamination ability of composite honeycomb panels.

[0038] 2. This invention achieves surface modification of the honeycomb core layer through a micron-level pit array, solving the problem of weak interlayer bonding and improving the structural stability of the composite honeycomb panel;

[0039] 3. This invention uses shape memory alloy wire mesh to enable composite honeycomb panels to possess shape memory characteristics, solving the problems of poor structural adaptability and insufficient surface functionality of traditional honeycomb panels, and enhancing surface friction performance and functionality;

[0040] 4. This invention achieves the self-healing function of composite honeycomb panels through microcapsules, solving the problem of cracks affecting the service life of traditional honeycomb panels and improving the durability and reliability of honeycomb panels. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the preparation process of the present invention;

[0042] Figure 2 This is a schematic diagram of the microcapsule repair process of the present invention;

[0043] Figure 3 This is a schematic diagram of the gradient dispersion process of the present invention;

[0044] Figure 4 This is a schematic diagram of the construction process of the conductive shielding layer of the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Please see Figure 1 , Figure 2 , Figure 3 and Figure 4 The present invention provides an embodiment of a composite honeycomb panel based on continuous fiber reinforcement, the preparation method of which includes the following steps:

[0047] S1. Modified polyphenylene sulfide particles are extruded to prepare honeycomb core blanks. The blanks are stretched into hexagonal honeycomb structures by a traction machine and cut into core plates with a thickness of 10-50mm. Then, the surfaces on both sides of the core plates are treated with plasma etching equipment with a power of 100-300W and a time of 30-90s. The gas flow ratio Ar:O2 = 5:1-3:1.

[0048] S2. Basalt fiber bundles are activated by plasma treatment, and then coated with polyphenylene sulfide resin by melt impregnation method. The impregnation temperature is 380-420℃ and the traction rate is 0.3-1.2m / min to form a prepreg tape with a single layer thickness of 0.1-0.25mm. The prepreg tapes are then stacked in the order of 0° / ±45° / 90°, with 4-8 layers.

[0049] S3. Mix nano-alumina with a particle size of 20-80nm with epoxy resin, curing agent and silicon carbide whiskers, and ultrasonically disperse for 30-60min to obtain an adhesive solution. Then, apply the adhesive solution to the surface of the honeycomb core layer and the bottom surface of the prepreg tape by electrostatic spraying. The spraying voltage is 30-50kV and the coating thickness is controlled at 50-150μm. After coating, cure at 80℃ for 2h, and then raise the temperature to 120℃ for 1h.

[0050] S4. The honeycomb core layer coated with the interface transition layer is stacked with the prepreg tape and placed in a vacuum hot press for pulse hot pressing: First stage: pressure 0.5-1MPa, temperature 200-230℃, hold for 30min, and remove air; Second stage: pressure 2-3MPa, temperature 360-380℃, hold for 60min, and melt and composite the resin.

[0051] S5. After cooling to room temperature, demold, cut to size, and then perform surface hardening by magnetron sputtering deposition of titanium nitride coating;

[0052] The preparation method further includes the following steps:

[0053] S31. The silicon carbide whiskers of the adhesive solution are dispersed by gradient centrifugation, with the rotation speed gradually increasing from 500 rpm to 3000 rpm at 10 min intervals, so that the whiskers form a concentration gradient along the vertical direction.

[0054] S32. Mix polyphenylene sulfide particles with 5-15wt% short-cut carbon fibers and 3-8wt% nano boron nitride, melt blend in a twin-screw extruder at 320-360℃, and then extrude and granulate.

[0055] S41. The heating rate of pulse hot pressing is 5-10℃ / min, the cooling rate is ≤8℃ / min, the vacuum degree is ≤10Pa, tensile stress is applied at 80-120℃, and after holding for 10-30min, it is water-cooled for shaping, and pre-deformed shape memory alloy wire mesh is used.

[0056] S42. Before proceeding to S4, lay silver-plated glass fiber cloth and graphene polyurethane film on the surface of the honeycomb core layer to set a conductive shielding layer.

[0057] S43. Urea-formaldehyde resin shell microcapsules were prepared by in-situ polymerization. The core material was dicyclopentadiene and Grubb catalyst in a mass ratio of 100:1. The capsule diameter was 50-200 μm and the shell thickness was 5-10 μm.

[0058] Microcapsules are evenly spread during the prepreg tape stacking process, with a density of 10. 4 -10 5 pcs / m 2 ;

[0059] When the microcapsules rupture due to damage to the board, keeping it at 60-80℃ for 30-60 minutes causes dicyclopentadiene to undergo a ring-opening metathesis polymerization reaction, thus repairing the cracks.

[0060] Furthermore, firstly, the basalt fiber bundles are immersed in an aqueous solution of silane coupling agent with a concentration of 5-10 g / L for 1-3 minutes to allow the fiber surface to fully adsorb the coupling agent molecules. Then, the fibers are placed in a forced-air drying oven and dried at 120-150℃ for 30-60 minutes. The high temperature causes the coupling agent to undergo a condensation reaction with the hydroxyl groups on the fiber surface, forming chemical bonds. This reduces the hydroxyl content on the fiber surface to 20%-40% of that before treatment, while introducing organic functional groups, which significantly improves the chemical compatibility between the fiber and polyphenylene sulfide resin.

[0061] Then, the treated basalt fiber bundles are roughened on the surface by plasma activation equipment. The plasma activation is carried out in an argon atmosphere with a power of 50-100W. Then, they are introduced into a melt impregnation device. The polyphenylene sulfide resin is in a molten state at 380-420℃. The fiber bundles are completely impregnated with resin at a traction rate of 0.3-1.2m / min. The prepreg tape is rolled into a single layer with a thickness of 0.1-0.25mm. When the prepreg tapes are stacked in the order of 0° / ±45° / 90°, a vacuum adsorption device is used to ensure that there are no air bubbles between the layers. The number of stacked layers is controlled by a counter to be 4-8 layers, forming a multi-axial orientation fiber distribution, which improves the in-plane isotropic mechanical properties of the board.

[0062] Finally, 5-30 wt% of 20-80 nm nano-alumina, 0.5-3 wt% of silicon carbide whiskers, 60-85 wt% of bisphenol A type epoxy resin, and 1-5 wt% of latent imidazole curing agent are mixed. The resin is first preheated to a flowable state at 50°C, then dispersed for 30-60 minutes using a 200-400W ultrasonic disperser to ensure uniform distribution of the nanoparticles. Afterward, a gradient centrifugation method is used, gradually increasing the speed to 3000 rpm, with 10-minute intervals between each stage. Silicon carbide whiskers form a vertical concentration gradient ΔC / C = 20%-40%. After centrifugation, the middle layer of adhesive is taken and electrostatically sprayed. The spraying voltage is controlled at 30-50kV to atomize the adhesive and adsorb it onto the surface of the honeycomb core layer and prepreg tape, forming a coating 50-150μm thick. During curing, the low molecular weight curing agent is first kept at 80℃ for 2 hours to allow it to react initially, and then the temperature is raised to 120℃ and kept for 1 hour to complete the crosslinking. The final glass transition temperature of the interface transition layer is ≥180℃, which improves the interlayer shear strength.

[0063] Please see Figure 1 , Figure 3 and Figure 4 This invention provides an embodiment of a composite honeycomb panel based on continuous fiber reinforcement, comprising a honeycomb core layer, a gradient reinforcement layer, and an interface transition layer. The honeycomb core layer is configured as a modified thermoplastic honeycomb structure. The interface transition layer is connected to both sides of the outer wall of the honeycomb core layer. The gradient reinforcement layer is bonded to the outer side of the interface transition layer. The gradient reinforcement layer is composed of continuous basalt fiber prepreg and thermoplastic resin, wherein the fibers of the thermoplastic resin are multiaxially oriented along the thickness direction. The interface transition layer is a nanoparticle-modified polymer film with a thickness of 50-150 μm, a nanoparticle size of 20-80 nm, and a mass percentage of 5%-15%.

[0064] The basalt fiber has a fiber volume fraction of 55%-65%, a layup angle of 0° / ±45° / 90° alternating, a single layer thickness of 0.1-0.25 mm, and a total number of layers ≥4. The basalt fiber is subjected to sequential surface immersion in a 5-10 g / L silane coupling agent aqueous solution for 1-3 min and drying at 120-150℃ for 30-60 min. After treatment, the hydroxyl content on the fiber surface is 20%-40% of that before treatment.

[0065] Furthermore, firstly, a 10-50mm thick polyphenylene sulfide (PPS) honeycomb core layer is fixed in the plasma etching equipment chamber. Argon and oxygen in a volume ratio of 5:1-3:1 are introduced, the equipment power is adjusted to 100-300W, and the processing time is 30-90s. Argon ions form micron-sized pits on the core layer surface through physical sputtering, while oxygen etches the surface polymer chains through oxidation. The two work together to control the pit depth to 5-20μm and the density to 100-300 pits / mm. 2 ;

[0066] Then, the uniformity of the pit array was observed using a scanning electron microscope, the Ra value was measured to be 1.5-3.0 μm using a stylus surface roughness meter, and the water contact angle was measured to be reduced to 40°-60° using a contact angle meter, indicating that the surface wettability was significantly improved. The rough interface and pit structure generated by etching can increase the mechanical interlocking effect of subsequent bonding, while the polar groups introduced by oxidation can enhance the interfacial chemical adsorption force.

[0067] Finally, for honeycomb cores with thinner walls (0.08-0.1mm), a lower power of 100-200W and a shorter etching time of 30-60s are used to avoid excessive etching that could damage the structure. For core layers with thicker walls (0.1-0.15mm), the power is increased to 200-300W and the etching time is extended to 60-90s to obtain a deeper pit structure. After etching, the core layer is bonded within 24 hours to avoid the degradation of surface polar groups due to environmental factors.

[0068] Please see Figure 1 , Figure 2 and Figure 4 One embodiment of the present invention provides a composite honeycomb panel based on continuous fiber reinforcement, wherein the honeycomb core material is polyphenylene sulfide, the honeycomb core has a hexagonal mesh structure with a wall thickness of 0.08-0.15 mm and a side length of 3-5 mm, and the surface is formed with a micron-scale pit array by plasma etching, the pit depth is 5-20 μm, and the density is 100-300 pits / mm. 2 ;

[0069] The plasma etching setting power is 100-300W, the processing time is 30-90s, the gas composition is argon and oxygen, the volume ratio of argon to oxygen is 5:1-3:1, the surface roughness Ra after etching is 1.5-3.0μm, and the contact angle is 40°-60°.

[0070] Furthermore, firstly, silicon carbide whiskers are gradient dispersed. Silicon carbide whiskers with an aspect ratio > 50:1 are added to the adhesive solution and pre-dispersed by stirring at a low speed of 200 rpm for 10 min. Then, the solution is transferred to a gradient centrifuge, with the speed set from 500 rpm and increasing by 500 rpm every 10 min until it reaches 3000 rpm. During centrifugation, the whiskers have different settling speeds due to the difference in aspect ratio. Finally, a gradient distribution is formed in the adhesive solution with a whisker concentration of C near the bottom of the honeycomb core layer and C+ΔC near the top of the gradient reinforcement layer. When taking the upper layer of adhesive solution after centrifugation, care is taken to avoid disturbing the gradient structure. The upper 2 / 3 of the adhesive solution is siphoned off for coating the gradient reinforcement layer side, and the lower layer of adhesive solution is used for the honeycomb core layer side.

[0071] Then, Ni-Ti-Cu alloy wires with an atomic ratio of 50:45:5 are woven into a mesh with a spacing of 2-5 mm and a wire diameter of 0.05-0.1 mm. The mesh is preheated in an oven at 80-120℃ for 5 min, and a pre-deformation amount of 5%-10% is applied. Then, it is quickly water-cooled for shaping. A 1-3 μm thick coating is plated onto the surface of the mesh using a chemical nickel-phosphorus alloy plating process. The plating solution consists of: 25 g / L nickel sulfate, 30 g / L sodium hypophosphite, and 10 g / L sodium acetate, with a pH of 4.5-5.0, a temperature of 85-90℃, and a time of 30-60 min. The coating can eliminate the oxide film on the surface of the mesh, making the surface resistance ≤0.5Ω / cm. Through the mechanical interlocking and chemical bonding between the nickel-phosphorus alloy and the thermoplastic resin, the interfacial bonding strength is increased to ≥40MPa.

[0072] Finally, a fiber laser cutting machine with a wavelength of 1064nm and a power of 50-100W was used to process the microtexture on the surface of the gradient reinforcement layer. The laser scanning speed was set to 500-1000mm / s and the pulse frequency to 20-50kHz. Cross grooves with a depth of 20-50μm, a width of 0.1-0.3mm, and an included angle of 60°-120° were processed by controlling the number of repeated scans to achieve a coverage of 30%-60%. During processing, nitrogen gas with a pressure of 0.1-0.2MPa was used to assist in purging to remove molten resin debris, ensuring that the radius of the groove edge rounded corners was ≤5μm and the surface roughness Ra was ≤2.0μm. The microtexture can increase the surface friction coefficient and improve the anti-slip performance of the plate. At the same time, the groove structure can guide the crack propagation path and improve the fatigue resistance.

[0073] Please see Figure 1 , Figure 2 and Figure 3This invention provides an embodiment of a composite honeycomb panel based on continuous fiber reinforcement. The nanoparticle-modified polymer film has a dispersion of ≤2.5, the nanoparticles are nano-alumina, the modified polymer is modified epoxy resin, the epoxy resin is bisphenol A type epoxy resin, the curing agent is a latent imidazole compound, and the glass transition temperature after curing is ≥180℃. The interface transition layer also contains 0.5-3wt% silicon carbide whiskers with an aspect ratio >50:1, which are distributed in a gradient along the thickness direction. The whisker content is C on the side near the honeycomb core layer and C+ΔC on the side near the gradient reinforcement layer, with ΔC / C = 20%-40%. The whisker surface is modified by KH-560 silane coupling agent, and the grafting rate is ≥90%.

[0074] The gradient reinforcement layer is embedded with a shape memory alloy mesh. The alloy composition is Ni-Ti-Cu, with an atomic ratio of 50:45:5. The wire diameter is 0.05-0.1 mm, the mesh spacing is 2-5 mm, the pre-deformation amount of the mesh is 5%-10%, the pre-deformation temperature is 80-120℃, the full recovery temperature is 150-180℃, and the recovery force is ≥50 MPa. The surface of the shape memory alloy mesh is coated with a nickel-phosphorus alloy layer with a thickness of 1-3 μm, a surface resistivity of ≤0.5 Ω / cm, and an interfacial bonding strength with thermoplastic resin of ≥40 MPa. The surface of the gradient reinforcement layer is laser-etched with microtextures, which include intersecting grooves with a depth of 20-50 μm, a groove width of 0.1-0.3 mm, an included angle of 60°-120°, a coverage of 30%-60%, a microtexture edge radius of ≤5 μm, and a surface roughness Ra of ≤2.0 μm.

[0075] Furthermore, firstly, a polyether ether ketone-based honeycomb core layer is prepared by adding polyphenylene sulfide particles, 5-15 wt% short-cut carbon fibers with a length of 0.5-1 mm, and 3-8 wt% nano-boron nitride with a particle size of 50-100 nm into a twin-screw extruder. The feeding section temperature is set to 280℃, the melting section to 320-360℃, and the extrusion section to 300℃, with a screw speed of 150-200 rpm. The fillers are uniformly dispersed through melt blending. After the extrudate is water-cooled, stretched, and pelletized, it is used to prepare a honeycomb core preform through an extrusion molding machine. During the preform traction, carbon fiber-polyphenylene sulfide composite fiber bundles with a diameter of 5-8 μm are simultaneously introduced. The carbon fiber-polyphenylene sulfide composite fiber bundles are pre-formed bundles with a carbon content of 60-70%. The fibers are distributed axially along the honeycomb wall through a guiding device, with the density controlled at 5-10 fibers / mm to improve the axial compressive strength of the honeycomb wall.

[0076] Then, a conductive shielding layer is constructed by cutting silver-plated glass fiber cloth with a fiber diameter of 5-10 μm and a silver plating layer thickness of 0.2-0.5 μm into honeycomb core layer size, laying it on the core layer surface, and then coating it with a graphene-modified polyurethane film. The graphene content is 2%-5% by mass, and the sheet thickness is 1-3 nm. The coating is performed by a blade coating method, controlling the film thickness to 0.05-0.2 mm. After drying at 80℃ for 1 h, a conductive network is formed. Subsequently, magnetron sputtering is performed with titanium nitride as the target material, sputtering power of 100-200 W, argon gas pressure of 0.5-1 Pa, and deposition time of 30-60 min to form a titanium nitride coating with a thickness of 0.5-2 μm. This further improves the surface hardness and conductive shielding effectiveness.

[0077] Finally, in a vacuum hot press, the pressure is first maintained at 0.5-1 MPa and the temperature at 200-230℃ for 30 minutes. The interlayer air is then removed using a vacuum pump with a vacuum degree ≤10Pa. The temperature is then increased to 360-380℃ at a rate of 5-10℃ / min, while the pressure is increased to 2-3 MPa. This is maintained for 60 minutes to allow the polyether ether ketone resin to fully melt and penetrate. During the cooling stage, the cooling rate is controlled by a program and is ≤8℃ / min. When the temperature drops to 80-120℃, a tensile stress of 0%-15% of the material's yield strength is applied to the sheet. This is maintained for 10-30 minutes before water cooling for shaping. This allows the shape memory alloy wire mesh to remember the pre-deformed state, which can generate a restoring force when heated subsequently, thus inhibiting crack propagation.

[0078] Please see Figure 1 , Figure 3 and Figure 4 This invention provides an embodiment of a composite honeycomb panel based on continuous fiber reinforcement. The thermoplastic resin is polyetheretherketone (PEEK), with a melt index of 10-25 g / 10 min, a glass transition temperature of 143°C, and a crystallinity of 35%-50%. A conductive shielding layer is provided between the honeycomb core layer and the gradient reinforcement layer. The conductive shielding layer is composed of silver-plated glass fiber cloth and graphene-modified polyurethane. The silver-plated glass fiber cloth has a fiber diameter of 5-10 μm, a silver plating layer thickness of 0.2-0.5 μm, a graphene mass percentage of 2%-5%, an average sheet thickness of 1-3 nm, a sheet resistivity ≤1 Ω / sq, and a thickness of 0.05-0.2 mm. A titanium nitride coating with a thickness of 0.5-2 μm is deposited on the surface of the conductive shielding layer by magnetron sputtering.

[0079] The hexagonal honeycomb wall of the honeycomb core layer is provided with carbon fiber-polyphenylene sulfide composite fibers with a diameter of 5-8 μm, distributed along the axial direction of the honeycomb wall, and a density of 5-10 fibers / mm.

[0080] Furthermore, firstly, urea-formaldehyde resin shell microcapsules were prepared in situ. 100 parts of formaldehyde solution and 50 parts of urea were added to a three-necked flask, the pH was adjusted to 8.5-9.0, and the temperature was raised to 60℃ for 30 min to obtain urea-formaldehyde prepolymer. Dicyclopentadiene and Grubb catalyst were mixed at a mass ratio of 100:1 as the core material and added to the prepolymer aqueous solution. The mixture was emulsified at a stirring speed of 300 rpm for 15 min to form an oil-in-water emulsion. Hydrochloric acid was then added dropwise to adjust the pH to 3.5-4.0, and the mixture was reacted at a constant temperature of 50℃ for 2 h. The urea-formaldehyde prepolymer condensed to form a shell that encapsulated the core material. Microcapsules with a diameter of 50-200 μm and a shell thickness of 5-10 μm were collected by sieving and dried and stored in a desiccator to prevent moisture absorption.

[0081] Then, during the prepreg tape stacking process, an automatic spreader is used to evenly spread the microcapsules between each layer of prepreg tape, and a vibrating screen is used to control the spreading density to 10. 4 -10 5 pcs / m 2 During application, maintain an ambient humidity of ≤40% to prevent the microcapsule shell from absorbing moisture and cracking. After application, use a light pressure roller with a pressure of 0.1-0.2MPa to embed the microcapsules into the surface of the prepreg tape, so that the microcapsules do not shift during the hot pressing process.

[0082] Finally, when the microcapsules rupture due to impact, the core material dicyclopentadiene flows out and seeps into the crack. The plate is then placed on a heating platform, heated to 60-80℃ and held for 30-60 minutes. The Grubb catalyst triggers the ring-opening metasomatic polymerization reaction of dicyclopentadiene, generating a polymer that fills the crack. At the same time, Joule heating is generated by energizing the shape memory alloy wire mesh through surface resistance heating, achieving rapid local heating and shortening the repair time.

[0083] Working principle: First, plasma etching forms a micron-scale pit array on the surface of the honeycomb core. Through the synergy of physical sputtering and chemical oxidation, the surface roughness Ra reaches 1.5-3.0μm, and the contact angle is reduced to 40°-60°. The pit structure generates a mechanical interlocking effect, and the polar groups increase the chemical adsorption force. The basalt fiber is condensed by silane coupling agent and activated by plasma to improve the fiber-resin interface bonding strength. The nano-alumina / silicon carbide whisker adhesive solution forms a vertical concentration gradient through gradient centrifugation, and a gradient transition layer is formed by electrostatic spraying. The pinning effect of nanoparticles and the bridging effect of whiskers are used to inhibit the propagation of interlayer cracks.

[0084] Then, 4-8 layers of continuous basalt fiber prepreg tape are stacked at 0° / ±45° / 90°, and air bubbles are eliminated by vacuum adsorption to form an in-plane isotropic distribution. Ni-Ti-Cu shape memory alloy wire mesh is subjected to tensile stress for shaping during the hot pressing and cooling stage. When the plate is heated to 150-180℃, it generates a recovery force of ≥50MPa, which actively counteracts thermal stress and crack propagation driving force. Laser microtexturing improves the surface friction coefficient and guides crack deflection and energy dissipation through the groove path. Combined with silver-plated glass fiber cloth and titanium nitride coating, a three-dimensional conductive network is constructed to achieve electromagnetic shielding.

[0085] Finally, the urea-formaldehyde resin microcapsules are encapsulated with dicyclopentadiene / Grubb catalyst. When the capsule ruptures due to crack propagation, the core material triggers ring-opening metathesis polymerization at 60-80℃. Simultaneously, the Joule heating effect of the shape memory alloy wire mesh achieves rapid local heating, and the crack filling is completed within 10-15 minutes. The cured interface transition layer and the gradient reinforcement layer form a modulus transition, effectively dispersing stress concentration.

[0086] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A composite honeycomb panel based on continuous fiber reinforcement, characterized in that: It includes a honeycomb core layer, a gradient reinforcement layer, and an interface transition layer. The honeycomb core layer is configured as a modified thermoplastic honeycomb structure. The upper and lower surfaces of the honeycomb core layer are connected to the interface transition layer. The outer surface of the interface transition layer is bonded to the gradient reinforcement layer. The gradient reinforcement layer is a prepreg tape composed of continuous basalt fiber prepreg thermoplastic resin. The prepreg tape is multiaxially oriented along the thickness direction. The interface transition layer is a nanoparticle-modified polymer film with a thickness of 50-150 μm, a nanoparticle size of 20-80 nm, and a nanoparticle mass ratio of 5%-15% relative to the interface transition layer. The nanoparticle-modified polymer film has a dispersion of ≤2.5, the nanoparticles are nano-alumina, the modified polymer is modified epoxy resin, the epoxy resin is bisphenol A type epoxy resin, the curing agent is a latent imidazole compound, and the glass transition temperature after curing is ≥180℃. The interface transition layer also contains 0.5-3wt% silicon carbide whiskers with an aspect ratio >50:1, which are distributed in a gradient along the thickness direction. The whisker content is C on the side near the honeycomb core layer and C+ΔC on the side near the gradient reinforcement layer, with ΔC / C = 20%-40%. The whisker surface is modified by KH-560 silane coupling agent, with a grafting rate ≥90%.

2. The composite honeycomb panel based on continuous fiber reinforcement according to claim 1, characterized in that: The honeycomb core material is polyphenylene sulfide, and the honeycomb core has a hexagonal grid structure with a wall thickness of 0.08-0.15 mm and a side length of 3-5 mm. The surface is formed by plasma etching to create a micron-level pit array with a pit depth of 5-20 μm.

3. A composite honeycomb panel based on continuous fiber reinforcement according to claim 2, characterized in that: The plasma etching setting power is 100-300W, the processing time is 30-90s, the gas composition is argon and oxygen, the volume ratio of argon to oxygen is 5:1-3:1, the surface roughness Ra after etching is 1.5-3.0μm, and the contact angle is 40°-60°.

4. A composite honeycomb panel based on continuous fiber reinforcement according to claim 1, characterized in that: The basalt fiber has a fiber volume fraction of 55%-65%, a layup angle of 0° / ±45° / 90° alternating, a single layer thickness of 0.1-0.25mm, and a total number of layers ≥4. Basalt fibers are first impregnated with a 5-10 g / L silane coupling agent aqueous solution for 1-3 min and then dried at 120-150℃ for 30-60 min. After treatment, the hydroxyl content on the fiber surface is 20%-40% of that before treatment.

5. A composite honeycomb panel based on continuous fiber reinforcement according to claim 1, characterized in that: The gradient reinforcement layer is embedded with a shape memory alloy wire mesh. The alloy composition is Ni-Ti-Cu, the atomic ratio of Ni:Ti:Cu is 50:45:5, the wire diameter is 0.05-0.1mm, the mesh spacing is 2-5mm, the wire mesh pre-deformation amount is 5%-10%, the pre-deformation temperature is 80-120℃, the complete recovery temperature is 150-180℃, the recovery stress is ≥50MPa, and the surface of the shape memory alloy wire mesh is coated with a nickel-phosphorus alloy layer with a thickness of 1-3μm, a surface resistivity of ≤0.5Ω / cm, and an interfacial bonding strength with thermoplastic resin of ≥40MPa. The surface of the gradient enhancement layer is laser-etched with microtextures, which include intersecting grooves with a depth of 20-50 μm, a groove width of 0.1-0.3 mm, an included angle of 60°-120°, a coverage of 30%-60%, a microtexture edge radius of ≤5 μm, and a surface roughness Ra≤2.0 μm.

6. A composite honeycomb panel based on continuous fiber reinforcement according to claim 1, characterized in that: The thermoplastic resin is polyetheretherketone (PEEK), with a melt index of 10-25 g / 10 min, a glass transition temperature of 143 °C, and a crystallinity of 35%-50%. A conductive shielding layer is provided between the honeycomb core layer and the gradient reinforcement layer. The conductive shielding layer is composed of silver-plated glass fiber cloth and graphene-modified polyurethane. The silver-plated glass fiber cloth has a fiber diameter of 5-10μm, a silver plating layer thickness of 0.2-0.5μm, a graphene mass ratio of 2%-5%, an average sheet thickness of 1-3nm, a sheet resistance of ≤1Ω / sq, and a thickness of 0.05-0.2mm. A titanium nitride coating with a thickness of 0.5-2μm is deposited on the surface of the conductive shielding layer by magnetron sputtering.

7. A composite honeycomb panel based on continuous fiber reinforcement according to claim 1, characterized in that: The hexagonal honeycomb wall of the honeycomb core layer is provided with carbon fiber-polyphenylene sulfide composite fibers with a diameter of 5-8 μm, which are distributed along the axial direction of the honeycomb wall.

8. A method for preparing a composite honeycomb panel based on continuous fiber reinforcement, applicable to the composite honeycomb panel based on continuous fiber reinforcement as described in any one of claims 1-7, characterized in that: The preparation method includes the following steps: S1. Modified polyphenylene sulfide particles are extruded to prepare honeycomb core blanks. The blanks are stretched into hexagonal honeycomb structures by a traction machine and cut into core plates with a thickness of 10-50mm. Then, the surfaces on both sides of the core plates are treated with plasma etching equipment with a power of 100-300W and a time of 30-90s. The gas flow ratio Ar:O2 = 5:1-3:

1. S2. Basalt fiber bundles are activated by plasma treatment, and then coated with polyetheretherketone resin by melt impregnation method. The impregnation temperature is 380-420℃ and the traction rate is 0.3-1.2m / min to form a prepreg tape with a single layer thickness of 0.1-0.25mm. The prepreg tapes are then stacked in the order of 0° / ±45° / 90°, with 4-8 layers. S3. Mix nano-alumina with a particle size of 20-80nm with epoxy resin, curing agent and silicon carbide whiskers, and ultrasonically disperse for 30-60min to obtain an adhesive solution. Then, apply the adhesive solution to the surface of the honeycomb core layer and the bottom surface of the prepreg tape by electrostatic spraying. The spraying voltage is 30-50kV and the coating thickness is controlled at 50-150μm. After coating, cure at 80℃ for 2h, and then raise the temperature to 120℃ for 1h. S4. The honeycomb core layer coated with the interface transition layer is stacked with the prepreg tape and placed in a vacuum hot press for pulse hot pressing: First stage: Pressure 0.5-1MPa, temperature 200-230℃, maintain for 30 minutes, and remove air; Second stage: Pressure 2-3MPa, temperature 360-380℃, hold for 60min, resin melt composite; S5. After cooling to room temperature, demold, cut to size, and then perform surface hardening by magnetron sputtering deposition of titanium nitride coating.

9. A method for preparing a composite honeycomb panel based on continuous fiber reinforcement according to claim 8, characterized in that: The preparation method further includes the following steps: S31. In step S3, the silicon carbide whiskers in the adhesive solution are dispersed by gradient centrifugation, with the rotation speed gradually increasing from 500 rpm to 3000 rpm at intervals of 10 min, so that the whiskers form a concentration gradient along the vertical direction. S32. In step S1, polyphenylene sulfide particles are mixed with 5-15 wt% short-cut carbon fibers and 3-8 wt% nano boron nitride, and then melt-blended in a twin-screw extruder at 320-360℃ and extruded into granules. S41. In step S4, the heating rate of the pulse hot pressing is 5-10℃ / min, the cooling rate is ≤8℃ / min, the vacuum degree is ≤10Pa, the gradient reinforcement layer is embedded with shape memory alloy wire mesh, tensile stress is applied at 80-120℃, and after holding for 10-30min, it is water-cooled and shaped, and the pre-deformed shape memory alloy wire mesh is used. S42. Before proceeding to S4, lay silver-plated glass fiber cloth and graphene polyurethane film on the surface of the honeycomb core layer to set a conductive shielding layer. S43. Urea-formaldehyde resin shell microcapsules were prepared by in-situ polymerization. The core material was dicyclopentadiene and Grubb catalyst in a mass ratio of 100:

1. The capsule diameter was 50-200 μm and the shell thickness was 5-10 μm. Microcapsules are evenly spread during the prepreg tape stacking process, with a density of 10. 4 -10 5 pcs / m 2 ; When the microcapsules rupture due to damage to the board, holding the temperature at 60-80℃ for 30-60 minutes causes dicyclopentadiene to undergo a ring-opening metathesis polymerization reaction, thus repairing the cracks.

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