Multifunctional layer synergistic lightning strike protection composite material and preparation method thereof

Abstract

The application discloses a multifunctional layer synergic lightning strike protection composite material, which comprises a carbon fiber reinforced resin base layer, and a lower conductive adhesive film, a graphite honeycomb interlayer, an upper conductive adhesive film, a zirconium oxide fiber paper heat insulation layer and an ultra-arranged carbon nanotube film conductive layer are sequentially arranged above the carbon fiber composite material bottom layer; thermoplastic microcapsules are filled in the pores of the graphite honeycomb interlayer. The application further discloses a preparation method of the multifunctional layer synergic lightning strike protection composite material. The multifunctional layer synergic lightning strike protection composite material provided by the application solves the problem that the viscosity rises due to the existing high content filler, which leads to the difficulty in forming process and the difficulty in inhibiting the adhesion damage of the composite material surface subjected to lightning strike.

Description

Technical Field

[0001] This invention belongs to the field of composite material lightning protection technology, specifically relating to multifunctional layer synergistic lightning protection composite materials, and also to a method for preparing multifunctional layer synergistic lightning protection composite materials. Background Technology

[0002] Carbon fiber reinforced resin matrix composites are widely used in the main load-bearing structures of aircraft, such as fuselages and wings, due to their excellent properties such as lightweight, high strength, and high designability. However, composite materials face a severe threat of lightning strikes during service. Statistics show that an aircraft may be struck by lightning on average once every 1,000 hours of flight. Unlike traditional metal materials, the insulating properties of the resin matrix make it difficult for the current generated by a lightning strike to be conducted quickly, leading to serious damage such as resin pyrolysis, fiber breakage, and interlayer delamination, which seriously threatens flight safety.

[0003] To address these issues, various lightning protection solutions have been developed. Surface protection technology involves attaching highly conductive layers such as silver, aluminum mesh, metal foil, or graphite and carbon nanotube coatings to the surface of composite materials. This allows lightning current to be rapidly conducted along the surface shunt path, suppressing adhesion damage from lightning strikes. However, the mismatch in thermal expansion coefficients between the highly conductive layer and the resin matrix leads to poor bonding between the protective layer and the composite material, making it susceptible to damage or detachment during lightning strikes. Material modification technology involves adding conductive fillers such as graphene and carbon nanotubes to the resin matrix within the composite material to form a three-dimensional conductive network. This enhances the material's conductivity, allowing lightning current to be dispersed and conducted within the composite material, suppressing conductive damage from lightning strikes. However, the increased viscosity due to high filler content makes molding processes difficult and also hinders the suppression of adhesion damage to the composite material surface from lightning strikes. Summary of the Invention

[0004] The purpose of this invention is to provide a multifunctional layer-synergistic lightning protection composite material, which solves the problem that the viscosity increase caused by the high content of fillers in existing materials leads to difficult molding processes and makes it difficult to suppress the adhesion damage to the surface of the composite material when struck by lightning.

[0005] Another objective of this invention is to provide a method for preparing a multifunctional layered synergistic lightning protection composite material.

[0006] The first technical solution adopted in this invention is a multifunctional layer-synergistic lightning protection composite material, which includes a carbon fiber reinforced resin substrate layer. Above the carbon fiber composite material substrate, there are sequentially arranged a lower conductive film, a graphite honeycomb interlayer, an upper conductive film, a zirconia fiber paper heat insulation layer, and a super-arranged carbon nanotube thin film conductive layer. The pores of the graphite honeycomb interlayer are filled with thermoplastic microcapsules.

[0007] The first technical solution of this invention is also characterized in that,

[0008] The carbon fiber reinforced resin substrate layer has a thickness of 1.5-2.0 mm and is prepared by hot pressing using T700 grade carbon fiber reinforced epoxy resin prepreg; the graphite honeycomb interlayer has a height of 3-5 mm; the zirconia fiber paper insulation layer has a thickness of 0.5-0.8 mm and an areal density of 80-120 g / m²; the super-aligned carbon nanotube thin film conductive layer has a thickness of 30-50 μm and an areal density ≤20 g / m². 2 Electrical conductivity ≥ 6 × 10 4 S / m.

[0009] The conductive layer of the super-arranged carbon nanotube film has a temporary nano-clay barrier layer with a thickness of 1-2 μm.

[0010] Another technical solution adopted in this invention is a method for preparing a multifunctional layer-synergistic lightning protection composite material, which includes the following steps: S1, using carbon fiber reinforced resin matrix as the bottom layer; and laying a conductive adhesive film on the bottom layer; S2, A graphite honeycomb interlayer is placed above the lower conductive adhesive film, and thermoplastic microcapsules are pre-injected into the pores of the graphite honeycomb interlayer. S3, a conductive adhesive film is laid on the graphite honeycomb interlayer, and then a zirconium oxide fiber paper heat insulation layer and a super-arranged carbon nanotube thin film conductive layer are sequentially laid on the conductive adhesive film to form a stacked structure. S4. The stacked structure is placed in an autoclave for curing to obtain a multifunctional layered synergistic lightning protection composite material.

[0011] The pressure in the autoclave of S4 is 0.5-0.8 MPa, the temperature is 130-150°C, and the time is 1.5-2 hours.

[0012] The preparation method of the carbon fiber reinforced resin substrate layer in S1 includes the following steps: S1.1, T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, with the resin content controlled at 35-45 wt%; S1.2 The carbon fiber reinforced epoxy resin prepreg obtained in S1.1 is cyclically laid up and stacked in the order of fiber orientation of 45°, 0°, -45° and 90°, and the total number of layers is controlled to be 8-12 to form a preform. S1.3. Place the preform in an autoclave and cure it for 1.5-2 hours at a temperature of 120-180°C and a pressure of 0.5-0.8MPa to obtain a carbon fiber reinforced resin substrate layer; The preparation steps of the conductive adhesive film are as follows: S1.4 After wiping the nylon mesh cloth clean with alcohol and drying it, place it in a 15-20 g / L tin chloride solution, add an appropriate amount of hydrochloric acid, and sensitize it for 10-15 minutes; after taking it out, wash it clean with distilled water. S1.5, the sensitized nylon mesh is arranged in a mixed solution of palladium chloride and boric acid and activated for 10-15 min; then placed in sodium hypophosphite solution and activated for 30-40 min; S1.6, prepare a 25 g / L silver nitrate aqueous solution, add 1-2% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water and stir until the solution is clear; finally add glucose and tartaric acid in a mass ratio of 0.6-1.0 and 0.2-0.4 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1.7 Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 involves hot-pressing high-temperature conductive silver paste and silver-plated nylon mesh fabric into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm. S1.9, The hot-pressed conductive film is placed between two sandblasted metal molds and cured in an oven under the following conditions: pressure 0.3-0.5MPa, temperature 160-180°C, and time 2-2.5h, to obtain the conductive film.

[0013] The preparation steps of the graphite honeycomb interlayer in S2 are as follows: S2.1 uses natural flake graphite as raw material, which is dry ball milled to obtain uniform fine powder, and then honeycomb sandwich preforms are prepared by molding or laser selective sintering process, with the thickness controlled at 3-5mm. S2.2, the preform is placed in a vacuum carbonization furnace and heated to 1800-2200°C at a heating rate of 5-10°C / min under argon or nitrogen protection, and held at that temperature for 1-2 hours for high-temperature carbonization treatment to obtain a graphite honeycomb interlayer. The preparation steps of thermoplastic microcapsules are as follows: S2.1.1, polyethylene-methacrylic acid copolymer particles are fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which are used as core material; S2.1.2 Select a low-melting-point thermoplastic material, heat it to 150°C to melt it into a transparent viscous liquid, and keep it at that temperature for later use; S2.1.3, Disperse the core material in the molten wall material to form an emulsion dispersion; S2.1.4, the emulsified dispersion is sprayed into a 100°C hot air stream through an atomizing device at an atomizing pressure of 0.2-0.4MPa, and the droplets are rapidly solidified to form microcapsules with a particle size of 220μm; S2.1.5, the obtained microcapsules are filled into the pores of the graphite honeycomb interlayer by vibration or negative pressure adsorption, and the filling volume accounts for 60-80% of the pore volume.

[0014] The pretreatment steps for the zirconia fiber paper insulation layer in S3 are as follows: Place zirconia fiber paper with a thickness of 0.5-0.8 mm and a surface density of 80-120 g / m² in an 80°C oven and dry for 2 hours to remove adsorbed moisture; The preparation steps of the conductive layer of superaligned carbon nanotube thin film are as follows: S3.1, Super-arranged carbon nanotube arrays were prepared by chemical vapor deposition at 700-800°C, with ethylene or methane as the carbon source and argon or hydrogen mixture as the carrier gas. S3.2, the carbon nanotube array is mechanically stretched at a speed of 10-50 mm / min to form a continuous film with a thickness controlled at 30-50 μm and an areal density ≤20 g / m²; S3.3, the obtained film is heat-treated in air at 350°C for 30 min to remove impurities and obtain a super-arranged carbon nanotube thin film conductive layer.

[0015] S3 includes a step of applying a temporary nano-clay barrier layer on the surface of the super-aligned carbon nanotube thin film before laying the conductive layer: Prepare a 10wt% nano-clay aqueous suspension, stir at 80°C for 2 hours and then cool; use an air spray gun to uniformly spray the suspension onto one side of the conductive layer of the super-arranged carbon nanotube film, with the spraying amount controlled at 5-10 g / m²; dry at 60°C for 2 hours to form a continuous barrier layer with a thickness of 1-2 μm.

[0016] The beneficial effects of this invention are: (1) The super-arranged carbon nanotube thin film conductive layer of the present invention has high electrical conductivity. As a surface conductive layer, it can quickly guide the lightning current to the grounding end, reduce Joule heat accumulation, and effectively suppress lightning damage.

[0017] (2) The zirconia fiber paper insulation layer of the present invention has excellent high temperature resistance and low thermal conductivity, which can effectively block the heat generated by lightning strikes from being transferred to the underlying structure and protect the carbon fiber reinforced resin substrate.

[0018] (3) The conductive adhesive film of the present invention is prepared by combining silver-plated nylon mesh cloth and conductive silver paste. It has high conductivity and is used for bonding and conducting electricity on both sides of the graphite honeycomb interlayer, ensuring smooth conduction of lightning current between layers and reducing interlayer contact resistance.

[0019] (4) The graphite honeycomb interlayer of the present invention is prepared with high-purity graphite material. While achieving lightweighting, the conductivity of the composite material in the thickness direction is enhanced by the conductivity of the graphite material itself, forming a three-dimensional conductive network and improving the overall lightning current conduction capability.

[0020] (5) The thermoplastic microcapsules of the present invention are filled in the pores of the graphite honeycomb interlayer to form an electrothermal self-healing structure. The Joule heat generated by lightning strikes is transferred to the capsules through the honeycomb pore walls, causing them to rupture and release the repair agent, filling any microcracks that may occur, effectively repairing lightning strike damage, and significantly improving the service life and reliability of the material. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating the preparation method of the multifunctional layered synergistic lightning protection composite material of the present invention. Detailed Implementation

[0022] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0023] The multifunctional layered synergistic lightning protection composite material provided by this invention has a layered synergistic stacked structure, which includes, from bottom to top, a carbon fiber reinforced resin substrate layer, a lower conductive film, a graphite honeycomb interlayer, an upper conductive film, a zirconia fiber paper thermal insulation layer, and a super-arranged carbon nanotube thin film conductive layer; wherein, the honeycomb pores of the graphite honeycomb interlayer are filled with thermoplastic microcapsules, and the multilayer structure synergistically achieves the integrated functions of structural load-bearing, lightning strike conduction, thermal insulation buffering, and damage suppression.

[0024] This invention also provides a method for preparing the above-mentioned multifunctional layer-synergistic lightning protection composite material, which is specifically implemented according to the following steps: S1, using carbon fiber reinforced resin matrix as the bottom layer; and laying a conductive adhesive film on the bottom layer; The carbon fiber reinforced resin substrate layer prepared in this step serves as the structural load-bearing layer of the composite material. The thickness of the finished product is controlled to be 1.5-2.0 mm. The specific preparation process is as follows: S1.1 Prepreg preparation: T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, and the resin content of the prepreg is controlled to be 35-45 wt%; S1.2 Layup preforming: Take 8-12 layers of the above prepreg, and use the fiber orientation of 45°, 0°, -45°, and 90° as a basic layup unit. Lay up and stack the prepregs in sequence according to the unit. After the layup is completed, a preform is formed; S1.3 Hot pressing curing: Place the obtained preform in a hot press and cure it for 1.5-2 hours at a temperature of 120-180℃ and a pressure of 0.5-0.8 MPa. After curing, allow it to cool naturally and demold to obtain the carbon fiber reinforced resin substrate layer for later use.

[0025] The conductive adhesive film prepared by this invention consists of a lower conductive adhesive film and an upper conductive adhesive film. The preparation process for both is the same, and the thickness of the finished product is controlled to be 0.15 mm. The lower conductive adhesive film is laid first, and the specific preparation and laying process is as follows: S1.4 After wiping the nylon mesh cloth clean with alcohol and drying it, place it in a 15-20 g / L tin chloride solution, add an appropriate amount of hydrochloric acid, and sensitize it for 10-15 minutes; after taking it out, wash it clean with distilled water. S1.5, the sensitized nylon mesh is arranged in a mixed solution of palladium chloride and boric acid and activated for 10-15 min; then placed in sodium hypophosphite solution and activated for 30-40 min; S1.6, prepare a 25 g / L silver nitrate aqueous solution, add 1-2% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water and stir until the solution is clear; finally, add glucose and tartaric acid in a mass ratio of 0.6-1.0 and 0.2-0.4 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1.7 Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 involves hot-pressing high-temperature conductive silver paste and silver-plated nylon mesh fabric into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm. S1.9, The hot-pressed conductive film is placed between two sandblasted metal molds and cured in an oven under the following conditions: pressure 0.3-0.5MPa, temperature 160-180°C, and time 2-2.5h, to obtain the conductive film.

[0026] S2, A graphite honeycomb interlayer is placed above the lower conductive adhesive film, and thermoplastic microcapsules are pre-injected into the pores of the graphite honeycomb interlayer. The preparation steps of the graphite honeycomb interlayer in S2 are as follows: S2.1, natural flake graphite is selected as raw material, and uniform fine powder is obtained by dry ball milling. The honeycomb interlayer preform is prepared by molding or laser selective sintering process, and the thickness is controlled to be 3-5mm; S2.2, the preform is placed in a vacuum carbonization furnace, and heated to 1800-2200°C at a heating rate of 5-10°C / min under argon or nitrogen protection, and held for 1-2h for high-temperature carbonization treatment to obtain the graphite honeycomb interlayer; The preparation steps of thermoplastic microcapsules are as follows: S2.1.1, polyethylene-methacrylic acid copolymer particles are fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which are used as core materials; S2.1.2, a low-melting-point thermoplastic material is selected and heated to 150°C to melt it into a transparent viscous liquid, which is then kept at this temperature for later use; S2.1.3, the core material is dispersed in a molten wall material to form an emulsion dispersion; S2.1.4, the emulsion dispersion is sprayed into a 100°C hot air stream through an atomizing device at an atomization pressure of 0.2-0.4 MPa, and the droplets are rapidly solidified to form microcapsules with a particle size of 220 μm; S2.1.5, the obtained microcapsules are filled into the pores of a graphite honeycomb interlayer by vibration or negative pressure adsorption, with the filling volume accounting for 60-80% of the pore volume.

[0027] S3, a conductive film prepared in the same way as the lower conductive film is laid on the graphite honeycomb interlayer, serving as the upper conductive film, and is laid flat on the upper surface of the completed graphite honeycomb interlayer. Then, a zirconium oxide fiber paper heat insulation layer and a super-arranged carbon nanotube thin film conductive layer are sequentially laid on the upper conductive film to form a stacked structure; The pretreatment steps for the zirconia fiber paper insulation layer in S3 are as follows: Place zirconia fiber paper with a thickness of 0.5-0.8 mm and a surface density of 80-120 g / m² in an 80°C oven and dry for 2 hours to remove adsorbed moisture; The preparation steps of the conductive layer of superaligned carbon nanotube thin film are as follows: S3.1, Super-arranged carbon nanotube arrays were prepared by chemical vapor deposition at 700-800°C, with ethylene or methane as the carbon source and argon or hydrogen mixture as the carrier gas. S3.2, the carbon nanotube array is mechanically stretched at a speed of 10-50 mm / min to form a continuous film with a thickness controlled at 30-50 μm and an areal density ≤20 g / m²; S3.3, the obtained film is heat-treated in air at 350°C for 30 min to remove impurities and obtain a super-arranged carbon nanotube thin film conductive layer.

[0028] In S3, before laying the super-aligned carbon nanotube thin film conductive layer, a step of applying a temporary nano-clay barrier layer on its surface is also included: Prepare a 10wt% nano-clay aqueous suspension, stir at 80°C for 2 hours and then cool; use an air spray gun to uniformly spray the suspension onto one side of the conductive layer of the super-arranged carbon nanotube film, with the spraying amount controlled at 5-10 g / m²; dry at 60°C for 2 hours to form a continuous barrier layer with a thickness of 1-2 μm.

[0029] Example 1 This embodiment provides a method for preparing a multifunctional layered synergistic lightning protection composite material, such as... Figure 1As shown, please follow these steps: S1. A carbon fiber reinforced resin substrate layer is prepared and a conductive adhesive film is laid. The carbon fiber reinforced resin substrate layer prepared in this step serves as the structural load-bearing layer of the composite material. The finished product size is 200mm×100mm×1.75mm. The specific preparation process is as follows: S1.1 Prepreg preparation: T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, and the resin content of the prepreg is controlled to be 40wt%; S1.2 Layup preforming: 10 layers of the above prepreg are taken, and the fiber orientations of 45°, 0°, -45°, and 90° are used as a basic layup unit. The layers are cyclically laid up and stacked in this unit order. After the layup is completed, a preform is formed; S1.3 Hot pressing curing: The obtained preform is placed in a hot press. The carbon fiber reinforced resin substrate was cured at 150℃ and 0.65MPa for 1.75h. After curing, it was naturally cooled and demolded to obtain the carbon fiber reinforced resin substrate layer for later use. The conductive film prepared in this embodiment consists of a lower conductive film and an upper conductive film. The preparation process of both is the same, and the thickness of the finished product is controlled to be 0.15mm. The lower conductive film is laid first. The specific preparation and laying process is as follows: S1.4 Sensitization treatment of mesh cloth: The nylon mesh cloth is cut to a size of 200mm×100mm, wiped clean with alcohol and dried, and then placed in a 17.5g / L tin chloride solution. An appropriate amount of hydrochloric acid is added, and the sensitization treatment is carried out for 12min. After taking it out, Wash thoroughly with distilled water; S1.5 Activation treatment: Arrange the sensitized nylon mesh in a mixed solution of palladium chloride and boric acid, and activate for 12 min; then place it in a sodium hypophosphite solution and activate for 35 min; wash thoroughly with distilled water after each treatment; S1.6 Preparation of chemical silver plating solution: Prepare a 25 g / L silver nitrate aqueous solution, add 1.5% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water, and stir until the solution is clear; finally, add glucose and tartaric acid with a mass ratio of 0.8 and 0.3 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1. 7. Chemical silver plating: Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 Hot pressing film formation: Hot press the high-temperature conductive silver paste and the silver-plated nylon mesh into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm; S1.9 Curing and molding: Place the hot-pressed conductive film between two sandblasted metal molds and cure it in an oven under the following conditions: pressure 0.4MPa, temperature 170°C, and time 2.25h to obtain the conductive film; Take one of the conductive films prepared above as the lower conductive film and lay it flat on the upper surface of the carbon fiber reinforced resin substrate.

[0030] S2 was used to prepare graphite honeycomb interlayers and thermoplastic microcapsules and complete the laying process; S2 places a 200mm×100mm×4mm graphite honeycomb interlayer on top of the lower conductive adhesive film. The pores of the graphite honeycomb interlayer are pre-injected with thermoplastic microcapsules. The preparation steps of the graphite honeycomb interlayer are as follows: S2.1 Preform preparation: Natural flake graphite is selected as raw material, and uniform fine powder is obtained by dry ball milling. The honeycomb interlayer preform is prepared by compression molding process, and the thickness is controlled to be 4mm; S2.2 High temperature carbonization treatment: The preform is placed in a vacuum carbonization furnace and heated to 2000°C at a heating rate of 7.5°C / min under argon protection, and held at that temperature for 1.5h for high temperature carbonization treatment to obtain the graphite honeycomb interlayer; The preparation and filling steps of the thermoplastic microcapsules are as follows: S2.1.1 Core material preparation: Polyethylene-methacrylic acid copolymer is used to prepare the core material. The particles were fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which were used as the core material; S2.1.2 Wall material melting: Low melting point thermoplastic polyethylene material was selected and heated to 150°C to melt it into a transparent viscous liquid, which was then kept at the temperature for later use; S2.1.3 Emulsification and dispersion: The core material was dispersed in the molten wall material and stirred to form a uniform emulsion dispersion; S2.1.4 Atomization and curing: The emulsion dispersion was sprayed into a 100°C hot air stream through an atomizing device at an atomization pressure of 0.3 MPa, and the droplets were rapidly cured to form microcapsules with a particle size of 220 μm; S2.1.5 Pore filling: The obtained microcapsules were filled into the pores of the graphite honeycomb interlayer by vibration, with the filling volume accounting for 70% of the pore volume; The filled graphite honeycomb interlayer was then placed flat on top of the lower conductive adhesive film.

[0031] S3 is layered with a conductive adhesive film, a zirconium oxide fiber paper insulation layer, and a super-arranged carbon nanotube thin film conductive layer to form a stacked structure.

[0032] S3 lays a conductive film prepared using the same method as the lower conductive film on the graphite honeycomb interlayer, as the upper conductive film, and lays it flat on the upper surface of the completed graphite honeycomb interlayer; then, a zirconia fiber paper insulation layer and a super-arranged carbon nanotube thin film conductive layer are sequentially laid on the upper conductive film to form a stacked structure; the pretreatment and laying steps of the zirconia fiber paper insulation layer are as follows: select zirconia fiber paper with a thickness of 0.65 mm and a surface density of 100 g / m², cut it to a size of 200 mm × 100 mm, and dry it in an 80°C oven for 2 hours to remove adsorbed moisture, completing the pretreatment; lay the pretreated zirconia fiber paper insulation layer flat on top of the upper conductive film; super-arranged... The preparation and laying steps of the carbon nanotube thin film conductive layer are as follows: S3.1 Carbon nanotube array preparation: A super-arranged carbon nanotube array is prepared at 750°C by chemical vapor deposition, with ethylene as the carbon source and a mixture of argon and hydrogen as the carrier gas; S3.2 Thin film stretching: The carbon nanotube array is mechanically stretched at a speed of 30 mm / min to form a continuous thin film with a thickness controlled at 40 μm and an areal density of 15 g / m²; S3.3 Thin film purification treatment: The obtained film is heat-treated in air at 350°C for 30 min to remove residual impurities and obtain the super-arranged carbon nanotube thin film conductive layer; The prepared super-arranged carbon nanotube thin film conductive layer is laid flat on top of the zirconium oxide fiber paper thermal insulation layer to complete the stacked structure preparation.

[0033] S4 hot pressing curing molding; The resulting stacked structure was placed in an autoclave, and the autoclaving pressure was controlled at 0.65 MPa and the curing temperature at 140°C. The structure was then kept under heat and pressure for 1.75 hours for curing. After curing, the structure was allowed to cool naturally to room temperature. After demolding, the multifunctional layer-synergistic lightning protection composite material of this embodiment was obtained.

[0034] Example 2 This embodiment provides a method for preparing a multifunctional layered synergistic lightning protection composite material, such as... Figure 1 As shown, please follow these steps: S1. A carbon fiber reinforced resin substrate layer is prepared and a conductive adhesive film is laid. The carbon fiber reinforced resin substrate layer prepared in this step serves as the structural load-bearing layer of the composite material. The finished product size is 200mm×100mm×1.5mm. The specific preparation process is as follows: S1.1 Prepreg preparation: T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, and the resin content of the prepreg is controlled to be 35wt%; S1.2 Layup preforming: Take 8 layers of the above prepreg, and use the fiber orientation of 45°, 0°, -45°, and 90° as a basic layup unit. Lay up and stack the prepregs in sequence according to the unit. After the layup is completed, a preform is formed; S1.3 Hot pressing curing: Place the obtained preform in a hot press. The material was cured at 120℃ and 0.5MPa for 1.5 hours. After curing, it was naturally cooled and demolded to obtain a carbon fiber reinforced resin substrate layer for later use. The conductive film prepared in this embodiment consists of a lower conductive film and an upper conductive film. The preparation process for both is the same, and the thickness of the finished product is controlled to be 0.15mm. The lower conductive film is laid first. The specific preparation and laying process is as follows: S1.4 Sensitization treatment of mesh fabric: The nylon mesh fabric is cut to a size of 200mm×100mm, wiped clean with alcohol and dried, and then placed in a 15g / L tin chloride solution. An appropriate amount of hydrochloric acid is added, and the sensitization treatment is carried out for 10 minutes. After removal, it is used... Wash thoroughly with distilled water; S1.5 Activation treatment: Arrange the sensitized nylon mesh in a mixed solution of palladium chloride and boric acid, and activate for 10 min; then place it in a sodium hypophosphite solution and activate for 30 min; wash thoroughly with distilled water after each treatment; S1.6 Preparation of chemical silver plating solution: Prepare a 25 g / L silver nitrate aqueous solution, add 1% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water, stirring until the solution is clear; finally, add glucose and tartaric acid in mass ratios of 0.6 and 0.2 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1. 7. Chemical silver plating: Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 Hot pressing film formation: Hot press the high-temperature conductive silver paste and the silver-plated nylon mesh into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm; S1.9 Curing and molding: Place the hot-pressed conductive film between two sandblasted metal molds and cure it in an oven under the following conditions: pressure 0.3MPa, temperature 160°C, and time 2 hours to obtain the conductive film; Take one of the conductive films prepared above as the lower conductive film and lay it flat on the upper surface of the carbon fiber reinforced resin substrate.

[0035] S2 was used to prepare graphite honeycomb interlayers and thermoplastic microcapsules and complete the laying process; S2 places a 200mm×100mm×3mm graphite honeycomb interlayer on top of the lower conductive adhesive film. The pores of the graphite honeycomb interlayer are pre-injected with thermoplastic microcapsules. The preparation steps of the graphite honeycomb interlayer are as follows: S2.1 Preform preparation: Natural flake graphite is selected as raw material, and uniform fine powder is obtained by dry ball milling. The honeycomb interlayer preform is prepared by compression molding process, and the thickness is controlled to be 3mm; S2.2 High temperature carbonization treatment: The preform is placed in a vacuum carbonization furnace and heated to 1800°C at a heating rate of 5°C / min under nitrogen protection, and held at that temperature for 1h for high temperature carbonization treatment to obtain the graphite honeycomb interlayer; The preparation and filling steps of the thermoplastic microcapsules are as follows: S2.1.1 Core material preparation: Polyethylene-methacrylic acid copolymer particles are prepared by... The material is fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which are used as the core material; S2.1.2 Wall material melting: Low melting point thermoplastic polyethylene material is selected and heated to 150°C to melt it into a transparent viscous liquid, which is then kept at the temperature for later use; S2.1.3 Emulsification and dispersion: The core material is dispersed in the molten wall material and stirred to form a uniform emulsion dispersion; S2.1.4 Atomization and curing: The emulsion dispersion is sprayed into a 100°C hot air stream through an atomizing device at an atomization pressure of 0.2 MPa, and the droplets are rapidly cured to form microcapsules with a particle size of 220 μm; S2.1.5 Pore filling: The obtained microcapsules are filled into the pores of the graphite honeycomb interlayer by negative pressure adsorption, with the filling volume accounting for 60% of the pore volume; The filled graphite honeycomb interlayer is then placed flat on top of the lower conductive adhesive film.

[0036] S3 is laid with a conductive adhesive film, a zirconium oxide fiber paper heat insulation layer and a super-arranged carbon nanotube thin film conductive layer to form a stacked structure; S3 lays a conductive film prepared using the same method as the lower conductive film on the graphite honeycomb interlayer, as the upper conductive film, and lays it flat on the upper surface of the completed graphite honeycomb interlayer; then, a zirconia fiber paper insulation layer and a super-aligned carbon nanotube thin film conductive layer are sequentially laid on the upper conductive film to form a stacked structure; the pretreatment and laying steps of the zirconia fiber paper insulation layer are as follows: select zirconia fiber paper with a thickness of 0.5 mm and a surface density of 80 g / m², cut it to a size of 200 mm × 100 mm, and dry it in an 80°C oven for 2 hours to remove adsorbed moisture, completing the pretreatment; lay the pretreated zirconia fiber paper insulation layer flat on top of the upper conductive film; super-aligned carbon nanotube... The preparation and laying steps of the conductive nanotube film are as follows: S3.1 Carbon nanotube array preparation: A super-arranged carbon nanotube array is prepared at 700°C by chemical vapor deposition, with methane as the carbon source and a mixture of argon and hydrogen as the carrier gas; S3.2 Film stretching: The carbon nanotube array is mechanically stretched at a speed of 10 mm / min to form a continuous film with a thickness controlled at 30 μm and an areal density of 18 g / m²; S3.3 Film purification: The obtained film is heat-treated in air at 350°C for 30 min to remove residual impurities and obtain the super-arranged carbon nanotube conductive film layer; The prepared super-arranged carbon nanotube conductive film layer is laid flat on top of the zirconium oxide fiber paper insulation layer to complete the stacked structure preparation.

[0037] S4 hot pressing curing molding; The resulting stacked structure was placed in an autoclave, and the autoclaving pressure was controlled at 0.5 MPa and the curing temperature at 130°C. The structure was then kept under heat and pressure for 2 hours. After curing, the structure was allowed to cool naturally to room temperature. After demolding, the multifunctional layer-synergistic lightning protection composite material of this embodiment was obtained.

[0038] Example 3 This embodiment provides a method for preparing a multifunctional layered synergistic lightning protection composite material, such as... Figure 1 As shown, please follow these steps: S1. A carbon fiber reinforced resin substrate layer is prepared and a conductive adhesive film is laid. The carbon fiber reinforced resin substrate layer prepared in this step serves as the structural load-bearing layer of the composite material. The finished product size is 200mm×100mm×2.0mm. The specific preparation process is as follows: S1.1 Prepreg preparation: T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, and the resin content of the prepreg is controlled to be 45wt%; S1.2 Layup preforming: 12 layers of the above prepreg are taken, and the fiber orientations of 45°, 0°, -45°, and 90° are used as a basic layup unit. The layers are cyclically laid up and stacked in this unit order to form a preform after the layup is completed; S1.3 Hot pressing curing: The obtained preform is placed in a hot press. In this embodiment, the conductive adhesive film is cured at 180℃ and 0.8MPa for 2 hours. After curing, it is naturally cooled and demolded to obtain a carbon fiber reinforced resin substrate layer for later use. The conductive adhesive film prepared in this embodiment consists of a lower conductive adhesive film and an upper conductive adhesive film. The preparation process of both is the same, and the thickness of the finished product is controlled to be 0.15mm. The lower conductive adhesive film is laid first. The specific preparation and laying process is as follows: S1.4 Sensitization treatment of mesh cloth: The nylon mesh cloth is cut to a size of 200mm×100mm, wiped clean with alcohol and dried, and then placed in a 20g / L tin chloride solution. An appropriate amount of hydrochloric acid is added, and the sensitization treatment is carried out for 15min. After taking it out, it is steamed. Wash thoroughly with distilled water; S1.5 Activation treatment: Arrange the sensitized nylon mesh in a mixed solution of palladium chloride and boric acid, and activate for 15 min; then place it in a sodium hypophosphite solution and activate for 40 min; wash thoroughly with distilled water after each treatment; S1.6 Preparation of chemical silver plating solution: Prepare a 25 g / L silver nitrate aqueous solution, add 2% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water, stirring until the solution becomes clear; finally, add glucose and tartaric acid in a mass ratio of 1.0 and 0.4 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1.7 Chemical silver plating: Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 Hot pressing film formation: Hot press the high-temperature conductive silver paste and the silver-plated nylon mesh into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm; S1.9 Curing and molding: Place the hot-pressed conductive film between two sandblasted metal molds and cure it in an oven under the following conditions: pressure 0.5MPa, temperature 180°C, and time 2.5h to obtain the conductive film; Take one of the conductive films prepared above as the lower conductive film and lay it flat on the upper surface of the carbon fiber reinforced resin substrate.

[0039] S2 was used to prepare graphite honeycomb interlayers and thermoplastic microcapsules and complete the laying process; S2 places a 200mm×100mm×5mm graphite honeycomb interlayer on top of the lower conductive adhesive film. The pores of the graphite honeycomb interlayer are pre-injected with thermoplastic microcapsules. The preparation steps of the graphite honeycomb interlayer are as follows: S2.1 Preform preparation: Natural flake graphite is selected as raw material, and uniform fine powder is obtained by dry ball milling. The honeycomb interlayer preform is prepared by laser selective sintering process, and the thickness is controlled to be 5mm; S2.2 High temperature carbonization treatment: The preform is placed in a vacuum carbonization furnace and heated to 2200°C at a heating rate of 10°C / min under argon protection, and held at that temperature for 2h for high temperature carbonization treatment to obtain the graphite honeycomb interlayer; The preparation and filling steps of the thermoplastic microcapsules are as follows: S2.1.1 Core material preparation: Polyethylene-methacrylic acid copolymer is used to prepare the core material. The particles were fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which were used as the core material; S2.1.2 Wall material melting: Low melting point thermoplastic polyethylene material was selected and heated to 150°C to melt it into a transparent viscous liquid, which was then kept at the temperature for later use; S2.1.3 Emulsification and dispersion: The core material was dispersed in the molten wall material and stirred to form a uniform emulsion dispersion; S2.1.4 Atomization and curing: The emulsion dispersion was sprayed into a 100°C hot air stream through an atomizing device at an atomization pressure of 0.4 MPa, and the droplets were rapidly cured to form microcapsules with a particle size of 220 μm; S2.1.5 Pore filling: The obtained microcapsules were filled into the pores of the graphite honeycomb interlayer by vibration, with the filling volume accounting for 80% of the pore volume; The filled graphite honeycomb interlayer was then placed flat on top of the lower conductive adhesive film.

[0040] S3 is layered with a conductive adhesive film, a zirconium oxide fiber paper insulation layer, and a super-arranged carbon nanotube thin film conductive layer to form a stacked structure.

[0041] S3 lays a conductive film, prepared using the same method as the lower conductive film, on the graphite honeycomb interlayer as the upper conductive film, and lays it flat on the upper surface of the completed graphite honeycomb interlayer. Then, a zirconia fiber paper insulation layer and a super-aligned carbon nanotube thin film conductive layer are sequentially laid on the upper conductive film to form a stacked structure. The pretreatment and laying steps of the zirconia fiber paper insulation layer are as follows: zirconia fiber paper with a thickness of 0.8 mm and a surface density of 120 g / m² is selected, cut to a size of 200 mm × 100 mm, and dried in an 80°C oven for 2 hours to remove adsorbed moisture, completing the pretreatment. The pretreated zirconia fiber paper insulation layer is then laid flat on top of the upper conductive film. The super-aligned carbon nanotube thin film conductive layer... The preparation and deposition steps of the nanotube thin film conductive layer are as follows: S3.1 Carbon nanotube array preparation: A super-arranged carbon nanotube array is prepared at 800°C by chemical vapor deposition, with ethylene as the carbon source and a mixture of argon and hydrogen as the carrier gas; S3.2 Thin film stretching: The carbon nanotube array is mechanically stretched at a speed of 50 mm / min to form a continuous thin film with a thickness controlled at 50 μm and an areal density of 20 g / m²; S3.3 Thin film purification treatment: The obtained film is heat-treated in air at 350°C for 30 min to remove residual impurities and obtain the super-arranged carbon nanotube thin film conductive layer; The prepared super-arranged carbon nanotube thin film conductive layer is flatly deposited on top of the zirconium oxide fiber paper thermal insulation layer to complete the stacked structure preparation.

[0042] S4 hot pressing curing molding; The resulting stacked structure was placed in an autoclave, and the autoclaving pressure was controlled at 0.8 MPa and the curing temperature at 150°C. The structure was then kept under heat and pressure for 1.5 hours for curing. After curing, the structure was allowed to cool naturally to room temperature. After demolding, the multifunctional layer-synergistic lightning protection composite material of this embodiment was obtained.

[0043] Example 4 This embodiment provides a method for preparing a multifunctional layered synergistic lightning protection composite material, such as... Figure 1 As shown, please follow these steps: S1. A carbon fiber reinforced resin substrate layer is prepared and a conductive adhesive film is laid. The carbon fiber reinforced resin substrate layer prepared in this step serves as the structural load-bearing layer of the composite material. The finished product size is 200mm×100mm×1.75mm. The specific preparation process is as follows: S1.1 Prepreg preparation: T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, and the resin content of the prepreg is controlled to be 40wt%; S1.2 Layup preforming: 10 layers of the above prepreg are taken, and the fiber orientations of 45°, 0°, -45°, and 90° are used as a basic layup unit. The layers are cyclically laid up and stacked in this unit order. After the layup is completed, a preform is formed; S1.3 Hot pressing curing: The obtained preform is placed in a hot press. The carbon fiber reinforced resin substrate was cured at 150℃ and 0.65MPa for 1.75h. After curing, it was naturally cooled and demolded to obtain the carbon fiber reinforced resin substrate layer for later use. The conductive film prepared in this embodiment consists of a lower conductive film and an upper conductive film. The preparation process of both is the same, and the thickness of the finished product is controlled to be 0.15mm. The lower conductive film is laid first. The specific preparation and laying process is as follows: S1.4 Sensitization treatment of mesh cloth: The nylon mesh cloth is cut to a size of 200mm×100mm, wiped clean with alcohol and dried, and then placed in a 17.5g / L tin chloride solution. An appropriate amount of hydrochloric acid is added, and the sensitization treatment is carried out for 12min. After taking it out, Wash thoroughly with distilled water; S1.5 Activation treatment: Arrange the sensitized nylon mesh in a mixed solution of palladium chloride and boric acid, and activate for 12 min; then place it in a sodium hypophosphite solution and activate for 35 min; wash thoroughly with distilled water after each treatment; S1.6 Preparation of chemical silver plating solution: Prepare a 25 g / L silver nitrate aqueous solution, add 1.5% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water, and stir until the solution is clear; finally, add glucose and tartaric acid with a mass ratio of 0.8 and 0.3 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1. 7. Chemical silver plating: Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 Hot pressing film formation: Hot press the high-temperature conductive silver paste and the silver-plated nylon mesh into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm; S1.9 Curing and molding: Place the hot-pressed conductive film between two sandblasted metal molds and cure it in an oven under the following conditions: pressure 0.4MPa, temperature 170°C, and time 2.25h to obtain the conductive film; Take one of the conductive films prepared above as the lower conductive film and lay it flat on the upper surface of the carbon fiber reinforced resin substrate.

[0044] S2 was used to prepare graphite honeycomb interlayers and thermoplastic microcapsules and complete the laying process; S2 places a 200mm×100mm×4mm graphite honeycomb interlayer on top of the lower conductive adhesive film. The pores of the graphite honeycomb interlayer are pre-injected with thermoplastic microcapsules. The preparation steps of the graphite honeycomb interlayer are as follows: S2.1 Preform preparation: Natural flake graphite is selected as raw material, and uniform fine powder is obtained by dry ball milling. The honeycomb interlayer preform is prepared by compression molding process, and the thickness is controlled to be 4mm; S2.2 High temperature carbonization treatment: The preform is placed in a vacuum carbonization furnace and heated to 2000°C at a heating rate of 7.5°C / min under argon protection, and held at that temperature for 1.5h for high temperature carbonization treatment to obtain the graphite honeycomb interlayer; The preparation and filling steps of the thermoplastic microcapsules are as follows: S2.1.1 Core material preparation: Polyethylene-methacrylic acid copolymer is used to prepare the core material. The particles were fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which were used as the core material; S2.1.2 Wall material melting: Low melting point thermoplastic polyethylene material was selected and heated to 150°C to melt it into a transparent viscous liquid, which was then kept at the temperature for later use; S2.1.3 Emulsification and dispersion: The core material was dispersed in the molten wall material and stirred to form a uniform emulsion dispersion; S2.1.4 Atomization and curing: The emulsion dispersion was sprayed into a 100°C hot air stream through an atomizing device at an atomization pressure of 0.3 MPa, and the droplets were rapidly cured to form microcapsules with a particle size of 220 μm; S2.1.5 Pore filling: The obtained microcapsules were filled into the pores of the graphite honeycomb interlayer by vibration, with the filling volume accounting for 70% of the pore volume; The filled graphite honeycomb interlayer was then placed flat on top of the lower conductive adhesive film.

[0045] S3, with a conductive adhesive film, a zirconium oxide fiber paper heat insulation layer and a super-arranged carbon nanotube thin film conductive layer with a nano-clay temporary barrier layer laid on it to form a stacked structure; S3. A conductive film prepared using the same method as the lower conductive film is laid on the graphite honeycomb interlayer as the upper conductive film, and is laid flat on the upper surface of the completed graphite honeycomb interlayer. Then, a zirconia fiber paper insulation layer and a super-arranged carbon nanotube thin film conductive layer are sequentially laid on the upper conductive film to form a stacked structure. The pretreatment and laying steps of the zirconia fiber paper insulation layer are as follows: Zirconia fiber paper with a thickness of 0.65 mm and a surface density of 100 g / m² is selected, cut to a size of 200 mm × 100 mm, and dried in an 80°C oven for 2 hours to remove adsorbed moisture, thus completing the pretreatment. The pretreated zirconia fiber paper insulation layer is laid flat on top of the upper conductive film. The preparation steps of the super-arranged carbon nanotube thin film conductive layer are as follows: S3.1 Carbon nanotube array preparation: A super-arranged carbon nanotube array is prepared at 750°C by chemical vapor deposition. The carbon source is ethylene, and the carrier gas is a mixture of argon and hydrogen. S3.2 Thin Film Stretching: The carbon nanotube array is mechanically stretched at a speed of 30 mm / min to form a continuous thin film with a thickness controlled at 40 μm and an areal density of 15 g / m². S3.3 Thin Film Purification: The obtained thin film is heat-treated in air at 350°C for 30 min to remove residual impurities and obtain a super-aligned carbon nanotube conductive layer. Before laying the super-aligned carbon nanotube conductive layer, a temporary nano-clay barrier layer is applied to its surface. The specific steps are as follows: a 10 wt% nano-clay aqueous suspension is prepared, stirred at 80°C for 2 h, and then cooled to room temperature; the suspension is uniformly sprayed onto one side of the super-aligned carbon nanotube conductive layer using an air spray gun, with a spraying amount controlled at 7.5 g / m²; it is dried at 60°C for 2 h to form a continuous barrier layer with a thickness of 1.5 μm; the super-aligned carbon nanotube conductive layer with the temporary nano-clay barrier layer is then laid flat on top of the zirconia fiber paper insulation layer to complete the stacked structure preparation.

[0046] S4 hot pressing curing molding and post-processing; The resulting stacked structure was placed in an autoclave, and the autoclaving pressure was controlled at 0.65 MPa and the curing temperature at 140°C. The structure was then kept under heat and pressure for 1.75 hours for curing. After curing, the structure was allowed to cool naturally to room temperature. After demolding, the surface nano-clay temporary barrier layer was removed by rinsing with deionized water to obtain a clean surface of the multifunctional layer-synergistic lightning protection composite material of this embodiment.

[0047] Example 5 This embodiment provides a method for preparing a multifunctional layered synergistic lightning protection composite material, such as... Figure 1 As shown, please follow these steps: S1. A carbon fiber reinforced resin substrate layer is prepared and a conductive adhesive film is laid. The carbon fiber reinforced resin substrate layer prepared in this step serves as the structural load-bearing layer of the composite material. The finished product size is 200mm×100mm×1.5mm. The specific preparation process is as follows: S1.1 Prepreg preparation: T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, and the resin content of the prepreg is controlled to be 35wt%; S1.2 Layup preforming: Take 8 layers of the above prepreg, and use the fiber orientation of 45°, 0°, -45°, and 90° as a basic layup unit. Lay up and stack the prepregs in sequence according to the unit. After the layup is completed, a preform is formed; S1.3 Hot pressing curing: Place the obtained preform in a hot press. The material was cured at 120℃ and 0.5MPa for 1.5 hours. After curing, it was naturally cooled and demolded to obtain a carbon fiber reinforced resin substrate layer for later use. The conductive film prepared in this embodiment consists of a lower conductive film and an upper conductive film. The preparation process for both is the same, and the thickness of the finished product is controlled to be 0.15mm. The lower conductive film is laid first. The specific preparation and laying process is as follows: S1.4 Sensitization treatment of mesh fabric: The nylon mesh fabric is cut to a size of 200mm×100mm, wiped clean with alcohol and dried, and then placed in a 15g / L tin chloride solution. An appropriate amount of hydrochloric acid is added, and the sensitization treatment is carried out for 10 minutes. After removal, it is used... Wash thoroughly with distilled water; S1.5 Activation treatment: Arrange the sensitized nylon mesh in a mixed solution of palladium chloride and boric acid, and activate for 10 min; then place it in a sodium hypophosphite solution and activate for 30 min; wash thoroughly with distilled water after each treatment; S1.6 Preparation of chemical silver plating solution: Prepare a 25 g / L silver nitrate aqueous solution, add 1% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water, stirring until the solution is clear; finally, add glucose and tartaric acid in mass ratios of 0.6 and 0.2 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1. 7. Chemical silver plating: Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 Hot pressing film formation: Hot press the high-temperature conductive silver paste and the silver-plated nylon mesh into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm; S1.9 Curing and molding: Place the hot-pressed conductive film between two sandblasted metal molds and cure it in an oven under the following conditions: pressure 0.3MPa, temperature 160°C, and time 2 hours to obtain the conductive film; Take one of the conductive films prepared above as the lower conductive film and lay it flat on the upper surface of the carbon fiber reinforced resin substrate.

[0048] S2 was used to prepare graphite honeycomb interlayers and thermoplastic microcapsules and complete the laying process; S2 places a 200mm×100mm×3mm graphite honeycomb interlayer on top of the lower conductive adhesive film. The pores of the graphite honeycomb interlayer are pre-injected with thermoplastic microcapsules. The preparation steps of the graphite honeycomb interlayer are as follows: S2.1 Preform preparation: Natural flake graphite is selected as raw material, and uniform fine powder is obtained by dry ball milling. The honeycomb interlayer preform is prepared by compression molding process, and the thickness is controlled to be 3mm; S2.2 High temperature carbonization treatment: The preform is placed in a vacuum carbonization furnace and heated to 1800°C at a heating rate of 5°C / min under nitrogen protection, and held at that temperature for 1h for high temperature carbonization treatment to obtain the graphite honeycomb interlayer; The preparation and filling steps of the thermoplastic microcapsules are as follows: S2.1.1 Core material preparation: Polyethylene-methacrylic acid copolymer particles are prepared by... The material is fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which are used as the core material; S2.1.2 Wall material melting: Low melting point thermoplastic polyethylene material is selected and heated to 150°C to melt it into a transparent viscous liquid, which is then kept at the temperature for later use; S2.1.3 Emulsification and dispersion: The core material is dispersed in the molten wall material and stirred to form a uniform emulsion dispersion; S2.1.4 Atomization and curing: The emulsion dispersion is sprayed into a 100°C hot air stream through an atomizing device at an atomization pressure of 0.2 MPa, and the droplets are rapidly cured to form microcapsules with a particle size of 220 μm; S2.1.5 Pore filling: The obtained microcapsules are filled into the pores of the graphite honeycomb interlayer by negative pressure adsorption, with the filling volume accounting for 60% of the pore volume; The filled graphite honeycomb interlayer is then placed flat on top of the lower conductive adhesive film.

[0049] S3 is laid with a conductive adhesive film, a zirconium oxide fiber paper heat insulation layer and a super-arranged carbon nanotube thin film conductive layer with a nano-clay temporary barrier layer to form a stacked structure; S3. A conductive film prepared using the same method as the lower conductive film is laid on the graphite honeycomb interlayer as the upper conductive film, and is laid flat on the upper surface of the completed graphite honeycomb interlayer. Then, a zirconia fiber paper insulation layer and a super-arranged carbon nanotube thin film conductive layer are sequentially laid on the upper conductive film to form a stacked structure. The pretreatment and laying steps of the zirconia fiber paper insulation layer are as follows: Zirconia fiber paper with a thickness of 0.5 mm and a surface density of 80 g / m² is selected, cut to a size of 200 mm × 100 mm, and dried in an 80°C oven for 2 hours to remove adsorbed moisture, thus completing the pretreatment. The pretreated zirconia fiber paper insulation layer is laid flat on top of the upper conductive film. The preparation steps of the super-arranged carbon nanotube thin film conductive layer are as follows: S3.1 Carbon nanotube array preparation: A super-arranged carbon nanotube array is prepared at 700°C by chemical vapor deposition. The carbon source is methane, and the carrier gas is a mixture of argon and hydrogen. S3.2 Thin Film Stretching: The carbon nanotube array is mechanically stretched at a speed of 10 mm / min to form a continuous thin film with a thickness controlled at 30 μm and an areal density of 18 g / m². S3.3 Thin Film Purification: The obtained film is heat-treated in air at 350°C for 30 min to remove residual impurities and obtain a super-aligned carbon nanotube conductive layer. Before laying the super-aligned carbon nanotube conductive layer, a nano-clay temporary barrier layer is applied to its surface. The specific steps are as follows: a 10 wt% nano-clay aqueous suspension is prepared, stirred at 80°C for 2 h, and then cooled to room temperature. The suspension is uniformly sprayed onto one side of the super-aligned carbon nanotube conductive layer using an air spray gun, with a spraying amount controlled at 5 g / m². It is dried at 60°C for 2 h to form a continuous barrier layer with a thickness of 1 μm. The super-aligned carbon nanotube conductive layer with the nano-clay temporary barrier layer is laid flat on top of the zirconia fiber paper insulation layer to complete the stacked structure preparation.

[0050] S4 hot pressing curing molding and post-processing; The resulting stacked structure was placed in an autoclave, and the autoclaving pressure was controlled at 0.5 MPa and the curing temperature at 130°C. The structure was then kept at the same temperature and pressure for 2 hours. After curing, the structure was allowed to cool naturally to room temperature. After demolding, the surface nano-clay temporary barrier layer was removed by rinsing with deionized water to obtain the clean surface of the multifunctional layer-synergistic lightning protection composite material of this embodiment.

[0051] Example 6 This embodiment provides a method for preparing a multifunctional layered synergistic lightning protection composite material, such as... Figure 1 As shown, please follow these steps: S1. A carbon fiber reinforced resin substrate layer is prepared and a conductive adhesive film is laid. The carbon fiber reinforced resin substrate layer prepared in this step serves as the structural load-bearing layer of the composite material. The finished product size is 200mm×100mm×2.0mm. The specific preparation process is as follows: S1.1 Prepreg preparation: T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, and the resin content of the prepreg is controlled to be 45wt%; S1.2 Layup preforming: 12 layers of the above prepreg are taken, and the fiber orientations of 45°, 0°, -45°, and 90° are used as a basic layup unit. The layers are cyclically laid up and stacked in this unit order to form a preform after the layup is completed; S1.3 Hot pressing curing: The obtained preform is placed in a hot press. In this embodiment, the conductive adhesive film is cured at 180℃ and 0.8MPa for 2 hours. After curing, it is naturally cooled and demolded to obtain a carbon fiber reinforced resin substrate layer for later use. The conductive adhesive film prepared in this embodiment consists of a lower conductive adhesive film and an upper conductive adhesive film. The preparation process of both is the same, and the thickness of the finished product is controlled to be 0.15mm. The lower conductive adhesive film is laid first. The specific preparation and laying process is as follows: S1.4 Sensitization treatment of mesh cloth: The nylon mesh cloth is cut to a size of 200mm×100mm, wiped clean with alcohol and dried, and then placed in a 20g / L tin chloride solution. An appropriate amount of hydrochloric acid is added, and the sensitization treatment is carried out for 15min. After taking it out, it is steamed. Wash thoroughly with distilled water; S1.5 Activation treatment: Arrange the sensitized nylon mesh in a mixed solution of palladium chloride and boric acid, and activate for 15 min; then place it in a sodium hypophosphite solution and activate for 40 min; wash thoroughly with distilled water after each treatment; S1.6 Preparation of chemical silver plating solution: Prepare a 25 g / L silver nitrate aqueous solution, add 2% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water, stirring until the solution becomes clear; finally, add glucose and tartaric acid in a mass ratio of 1.0 and 0.4 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1.7 Chemical silver plating: Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 Hot pressing film formation: Hot press the high-temperature conductive silver paste and the silver-plated nylon mesh into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm; S1.9 Curing and molding: Place the hot-pressed conductive film between two sandblasted metal molds and cure it in an oven under the following conditions: pressure 0.5MPa, temperature 180°C, and time 2.5h to obtain the conductive film; Take one of the conductive films prepared above as the lower conductive film and lay it flat on the upper surface of the carbon fiber reinforced resin substrate.

[0052] S2 was used to prepare graphite honeycomb interlayers and thermoplastic microcapsules and complete the laying process; S2 places a 200mm×100mm×5mm graphite honeycomb interlayer on top of the lower conductive adhesive film. The pores of the graphite honeycomb interlayer are pre-injected with thermoplastic microcapsules. The preparation steps of the graphite honeycomb interlayer are as follows: S2.1 Preform preparation: Natural flake graphite is selected as raw material, and uniform fine powder is obtained by dry ball milling. The honeycomb interlayer preform is prepared by laser selective sintering process, and the thickness is controlled to be 5mm; S2.2 High temperature carbonization treatment: The preform is placed in a vacuum carbonization furnace and heated to 2200°C at a heating rate of 10°C / min under argon protection, and held at that temperature for 2h for high temperature carbonization treatment to obtain the graphite honeycomb interlayer; The preparation and filling steps of the thermoplastic microcapsules are as follows: S2.1.1 Core material preparation: Polyethylene-methacrylic acid copolymer is used to prepare the core material. The particles were fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which were used as the core material; S2.1.2 Wall material melting: Low melting point thermoplastic polyethylene material was selected and heated to 150°C to melt it into a transparent viscous liquid, which was then kept at the temperature for later use; S2.1.3 Emulsification and dispersion: The core material was dispersed in the molten wall material and stirred to form a uniform emulsion dispersion; S2.1.4 Atomization and curing: The emulsion dispersion was sprayed into a 100°C hot air stream through an atomizing device at an atomization pressure of 0.4 MPa, and the droplets were rapidly cured to form microcapsules with a particle size of 220 μm; S2.1.5 Pore filling: The obtained microcapsules were filled into the pores of the graphite honeycomb interlayer by vibration, with the filling volume accounting for 80% of the pore volume; The filled graphite honeycomb interlayer was then placed flat on top of the lower conductive adhesive film.

[0053] S3 is laid with a conductive adhesive film, a zirconium oxide fiber paper heat insulation layer and a super-arranged carbon nanotube thin film conductive layer with a nano-clay temporary barrier layer to form a stacked structure; S3. A conductive film prepared using the same method as the lower conductive film is laid on the graphite honeycomb interlayer as the upper conductive film, and is laid flat on the upper surface of the completed graphite honeycomb interlayer. Then, a zirconia fiber paper insulation layer and a super-arranged carbon nanotube thin film conductive layer are sequentially laid on the upper conductive film to form a stacked structure. The pretreatment and laying steps of the zirconia fiber paper insulation layer are as follows: Zirconia fiber paper with a thickness of 0.8 mm and a surface density of 120 g / m² is selected, cut to a size of 200 mm × 100 mm, and dried in an 80°C oven for 2 hours to remove adsorbed moisture, thus completing the pretreatment. The pretreated zirconia fiber paper insulation layer is laid flat on top of the upper conductive film. The preparation steps of the super-arranged carbon nanotube thin film conductive layer are as follows: S3.1 Carbon nanotube array preparation: A super-arranged carbon nanotube array is prepared at 800°C by chemical vapor deposition. The carbon source is ethylene, and the carrier gas is a mixture of argon and hydrogen. S3.2 Thin Film Stretching: The carbon nanotube array is mechanically stretched at a speed of 50 mm / min to form a continuous thin film with a thickness controlled at 50 μm and an areal density of 20 g / m². S3.3 Thin Film Purification: The obtained film is heat-treated in air at 350°C for 30 min to remove residual impurities and obtain a super-aligned carbon nanotube conductive layer. Before laying the super-aligned carbon nanotube conductive layer, a temporary nano-clay barrier layer is applied to its surface. The specific steps are as follows: a 10 wt% nano-clay aqueous suspension is prepared, stirred at 80°C for 2 h, and then cooled to room temperature. The suspension is uniformly sprayed onto one side of the super-aligned carbon nanotube conductive layer using an air spray gun, with a spraying amount controlled at 10 g / m². It is dried at 60°C for 2 h to form a continuous barrier layer with a thickness of 2 μm. The super-aligned carbon nanotube conductive layer with the temporary nano-clay barrier layer is laid flat on top of the zirconia fiber paper insulation layer to complete the stacked structure preparation.

[0054] S4 hot pressing curing molding and post-processing; The resulting stacked structure was placed in an autoclave, and the autoclaving pressure was controlled at 0.8 MPa and the curing temperature at 150°C. The structure was then kept under heat and pressure for 1.5 hours for curing. After curing, the structure was allowed to cool naturally to room temperature. After demolding, the surface nano-clay temporary barrier layer was removed by rinsing with deionized water to obtain a clean surface of the multifunctional layer-synergistic lightning protection composite material of this embodiment.

[0055] In summary, the multifunctional layered lightning protection composite material prepared by this invention is a multi-layered, integrated layered structure that integrates multiple functions such as structural load-bearing, lightning current conduction, thermal insulation and buffering, and damage self-repair. The super-arranged carbon nanotube thin film conductive layer can rapidly and uniformly conduct large lightning currents, while the zirconia fiber paper thermal insulation layer can effectively block the inward transmission of high-temperature arcs, significantly reducing ablation and structural damage caused by lightning strikes. The added nano-clay temporary barrier layer can prevent conductivity attenuation caused by resin wetting of the conductive layer during hot-pressing curing, ensuring stable lightning conduction performance. The thermoplastic microcapsules within the graphite honeycomb interlayer can self-repair lightning cracks. The overall structure does not require additional fasteners, fundamentally avoiding the risk of lightning ablation at connection points. It achieves lightweight while maintaining excellent mechanical properties, resulting in superior lightning protection and structural service stability.

Claims

1. A multifunctional layered synergistic lightning protection composite material, characterized in that, The material includes a carbon fiber reinforced resin substrate layer, and above the carbon fiber composite substrate layer, a lower conductive adhesive film, a graphite honeycomb interlayer, an upper conductive adhesive film, a zirconia fiber paper heat insulation layer, and a super-arranged carbon nanotube thin film conductive layer are sequentially disposed; the pores of the graphite honeycomb interlayer are filled with thermoplastic microcapsules.

2. The multifunctional layered synergistic lightning protection composite material according to claim 1, characterized in that, The carbon fiber reinforced resin substrate layer has a thickness of 1.5-2.0 mm and is prepared by hot pressing using T700 grade carbon fiber reinforced epoxy resin prepreg; the graphite honeycomb interlayer has a height of 3-5 mm; and the zirconium oxide fiber paper insulation layer has a thickness of 0.5-0.8 mm and a surface density of 80-120 g / m².

3. The multifunctional layered synergistic lightning protection composite material according to claim 1, characterized in that, The thickness of the super-aligned carbon nanotube film conductive layer is 30-50 μm, the area density is ≤20 g / m 2 , and the conductivity is ≥6×10 4 S / m.

4. The multifunctional layered synergistic lightning protection composite material according to claim 1, characterized in that, The conductive layer of the super-arranged carbon nanotube film is provided with a temporary nano-clay barrier layer, the thickness of which is 1-2 μm.

5. A method for preparing a multifunctional layered synergistic lightning protection composite material, characterized in that, Using the multifunctional layered lightning protection composite material according to any one of claims 1-4, the steps include: S1, using carbon fiber reinforced resin matrix as the bottom layer; and laying a conductive adhesive film on the bottom layer; S2, a graphite honeycomb interlayer is placed above the lower conductive adhesive film, and thermoplastic microcapsules are pre-injected into the pores of the graphite honeycomb interlayer; S3, a conductive adhesive film is laid on the graphite honeycomb interlayer, and then a zirconium oxide fiber paper heat insulation layer and a super-arranged carbon nanotube thin film conductive layer are sequentially laid on the conductive adhesive film to form a stacked structure; S4, the stacked structure is placed in an autoclave for curing to obtain a multifunctional layered synergistic lightning protection composite material.

6. The preparation method of the multifunctional layer-synergistic lightning protection composite material according to claim 5, characterized in that, The pressure in the autoclave in S4 is 0.5-0.8 MPa, the temperature is 130-150°C, and the time is 1.5-2 hours.

7. The preparation method of the multifunctional layer-synergistic lightning protection composite material according to claim 5, characterized in that, The preparation method of the carbon fiber reinforced resin substrate layer in S1 includes the following steps: S1.1, T700 grade high-strength carbon fiber is prepared into carbon fiber reinforced epoxy resin prepreg, with the resin content controlled at 35-45 wt%; S1.2 The carbon fiber reinforced epoxy resin prepreg obtained in S1.1 is cyclically laid up and stacked in the order of fiber orientation of 45°, 0°, -45° and 90°, and the total number of layers is controlled to be 8-12 to form a preform. S1.

3. Place the preform in an autoclave and cure it for 1.5-2 hours at a temperature of 120-180°C and a pressure of 0.5-0.8MPa to obtain a carbon fiber reinforced resin substrate layer; The preparation steps of the lower conductive adhesive film are as follows: S1.4 After wiping the nylon mesh cloth clean with alcohol and drying it, place it in a 15-20 g / L tin chloride solution, add an appropriate amount of hydrochloric acid, and sensitize it for 10-15 minutes; after taking it out, wash it clean with distilled water. S1.5, the sensitized nylon mesh is arranged in a mixed solution of palladium chloride and boric acid and activated for 10-15 min; then placed in sodium hypophosphite solution and activated for 30-40 min; S1.6, prepare a 25 g / L silver nitrate aqueous solution, add 1-2% (by volume) of 2 mol / L sodium hydroxide solution to it, and stir continuously; then add concentrated ammonia water and stir until the solution is clear; finally, add glucose and tartaric acid in a mass ratio of 0.6-1.0 and 0.2-0.4 to silver nitrate, respectively, and stir until a homogeneous system is formed to prepare the silver plating solution; S1.7 Immerse the activated nylon mesh in the silver plating solution, react at room temperature for 1 hour, then remove and air dry; S1.8 involves hot-pressing high-temperature conductive silver paste and silver-plated nylon mesh fabric into a film at 90°C and 5MPa, with the thickness controlled at 0.15mm. S1.9, The hot-pressed conductive film is placed between two sandblasted metal molds and cured in an oven under the following conditions: pressure 0.3-0.5MPa, temperature 160-180°C, and time 2-2.5h, to obtain the conductive film.

8. The method for preparing the multifunctional layered synergistic lightning protection composite material according to claim 5, characterized in that, The steps for preparing the graphite honeycomb interlayer described in S2 are as follows: S2.1 uses natural flake graphite as raw material, which is dry ball milled to obtain uniform fine powder, and then honeycomb sandwich preforms are prepared by molding or laser selective sintering process, with the thickness controlled at 3-5mm. S2.2, the preform is placed in a vacuum carbonization furnace and heated to 1800-2200°C at a heating rate of 5-10°C / min under argon or nitrogen protection, and held at that temperature for 1-2 hours for high-temperature carbonization treatment to obtain a graphite honeycomb interlayer. The preparation steps of the thermoplastic microcapsules are as follows: S2.1.1, polyethylene-methacrylic acid copolymer particles are fed into a dry ball mill to obtain microparticles with a particle size of 200 μm, which are used as core material; S2.1.2 Select a low-melting-point thermoplastic material, heat it to 150°C to melt it into a transparent viscous liquid, and keep it at that temperature for later use; S2.1.3, Disperse the core material in the molten wall material to form an emulsion dispersion; S2.1.4, the emulsified dispersion is sprayed into a 100°C hot air stream through an atomizing device at an atomizing pressure of 0.2-0.4MPa, and the droplets are rapidly solidified to form microcapsules with a particle size of 220μm; S2.1.5, the obtained microcapsules are filled into the pores of the graphite honeycomb interlayer by vibration or negative pressure adsorption, and the filling volume accounts for 60-80% of the pore volume.

9. The method for preparing the multifunctional layered synergistic lightning protection composite material according to claim 5, characterized in that, The pretreatment steps for the zirconia fiber paper insulation layer in S3 are as follows: Place zirconia fiber paper with a thickness of 0.5-0.8 mm and a surface density of 80-120 g / m² in an 80°C oven and dry for 2 hours to remove adsorbed moisture; The preparation steps of the super-aligned carbon nanotube thin film conductive layer are as follows: S3.1, Super-arranged carbon nanotube arrays were prepared by chemical vapor deposition at 700-800°C, with ethylene or methane as the carbon source and argon or hydrogen mixture as the carrier gas. S3.2, the carbon nanotube array is mechanically stretched at a speed of 10-50 mm / min to form a continuous film with a thickness controlled at 30-50 μm and an areal density ≤20 g / m²; S3.3, the obtained film is heat-treated in air at 350°C for 30 min to remove impurities and obtain a super-arranged carbon nanotube thin film conductive layer.

10. The method for preparing the multifunctional layered synergistic lightning protection composite material according to claim 5, characterized in that, In step S3, before laying the super-aligned carbon nanotube thin film conductive layer, a temporary nano-clay barrier layer is applied to its surface. Prepare a 10wt% nano-clay aqueous suspension, stir at 80°C for 2 hours and then cool; use an air spray gun to uniformly spray the suspension onto one side of the conductive layer of the super-arranged carbon nanotube film, with the spraying amount controlled at 5-10 g / m²; dry at 60°C for 2 hours to form a continuous barrier layer with a thickness of 1-2 μm.

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