Lightning protection composite board and preparation method and application thereof

Abstract

This invention relates to a lightning protection composite material, its preparation method, and its applications. The lightning protection composite material includes a substrate with a first end and a second end disposed opposite to each other. At least one conductive element is embedded in the second end of the substrate. The substrate has a first surface and a second surface disposed opposite to each other, both extending from the first end to the second end. The conductive element extends from the first surface through the second surface. At least a portion of the first surface and at least a portion of the second surface are covered with a conductive rubber layer, and the conductive rubber layer covering the first surface extends at least from the first end to the second end, and the conductive rubber layer covering the second surface extends at least from the first end to the second end. This invention solves the problem of open conductive paths in composite materials used in aircraft due to abrasion caused by deflection, friction, etc., during operation.

Description

Technical Field

[0001] This application relates to the field of materials, specifically to a lightning protection composite board, its preparation method, and its uses. Background Technology

[0002] Fiber-reinforced resin matrix composites have been widely used in the aerospace field due to their advantages such as light weight, high strength, good structural designability, and ease of achieving integrated structural and functional molding. Reinforcing fibers and resin are two crucial components of resin matrix composites. Generally, the organic resin matrix possesses insulating properties, and with the exception of a few reinforcing fibers like carbon fiber, most reinforcing fibers are also poor conductors of electric current. This results in poor overall electrical conductivity of resin matrix composites. However, aircraft are susceptible to harsh environments such as lightning strikes during service. If electrical charges cannot be effectively discharged, severe thermal ablation damage can occur on the surface of the composite material, affecting the structural stiffness and strength of the composite components and thus jeopardizing the operational safety of the aircraft.

[0003] Traditional methods for improving the conductivity of composite materials used in aircraft include laying metal conductive meshes or spraying conductive coatings on the surface of composite components. However, laying metal conductive meshes increases the structural weight of the aircraft, reducing its maneuverability and fuel economy. Poor adhesion between the conductive coating and the composite material interface, leading to coating peeling during service, is also a key factor limiting the application of conductive coatings. Currently, in the sealing structures of stealth fighters, composite components must withstand fatigue conditions involving long-term, large-deflection deformation. This can cause the rigid metal conductive mesh to break, exacerbating the peeling of the conductive coating from moving parts. Furthermore, frictional losses at the moving ends of the sealing composite structure can cause discontinuities in the conductive pathways between the upper and lower surfaces of the composite material, hindering the discharge of charge from the outer surface after a lightning strike.

[0004] Therefore, this invention is proposed. Summary of the Invention

[0005] The main objective of this invention is to improve a lightning protection composite material, its preparation method, and its applications, thereby solving the problem of open conductive paths caused by deflection, friction, and other abrasion of composite materials in aircraft during operation.

[0006] To achieve the above objectives, the present invention provides the following technical solutions.

[0007] A first aspect of the present invention provides a lightning protection composite board, which includes a substrate having a first end and a second end disposed opposite to each other, and at least one conductive element is embedded in the second end of the substrate.

[0008] The substrate has a first surface and a second surface disposed opposite to each other, the first surface and the second surface extending from the first end to the second end respectively, and the conductive element penetrating from the first surface to the second surface;

[0009] At least a portion of the first surface and at least a portion of the second surface are covered with a conductive rubber layer, and the conductive rubber layer covering the first surface extends at least from the first end to the second end, and the conductive rubber layer covering the second surface extends at least from the first end to the second end.

[0010] Therefore, by embedding a metal part in the second end of the substrate, which can serve as the movable friction end of the plate, the present invention can realize the connection of the conductive circuits of the two surfaces (the first surface and the second surface) of the composite plate. This ensures that when the outer surface of the composite plate is subjected to electrical loads such as lightning strikes, the charge can be smoothly discharged through the conductive circuit, effectively preventing the problem of open circuits in the conductive path caused by the erosion of the conductive rubber layer at the movable friction end.

[0011] In some implementations, multiple conductive elements are included;

[0012] The width direction of the substrate extends from the first end to the second end, the thickness direction extends from the first surface to the second surface, and the length direction of the substrate extends perpendicular to both the first and second directions. The plurality of conductive elements are distributed at equal intervals along the length direction.

[0013] The evenly spaced distribution of multiple conductive components can not only meet the requirements of circuit conduction on both sides of the substrate, but also achieve weight reduction. At the same time, the uniform distribution of conductivity throughout the composite board helps to extend its service life.

[0014] In some embodiments, the side length of the conductive element along the width direction is 5% to 20% of the width of the substrate.

[0015] Since the density of conductive components is usually greater than that of the substrate, the size of the conductive components does not need to be too large. As long as they can effectively conduct the circuit, their width is usually 5% to 20% of the substrate width to meet the above requirements.

[0016] For the same purpose, in some embodiments, the sum of the side lengths of all the conductive elements along the length direction is 5% to 20% of the length of the substrate.

[0017] In some embodiments, the two opposing surfaces of all the conductive elements are flush with the first surface and the second surface, respectively.

[0018] The conductive components are flush with the substrate surface, which can reduce wind resistance and maintain the regularity of the material's shape.

[0019] In some embodiments, the conductive element is block-shaped.

[0020] In some implementations, all conductive elements have the same shape and size.

[0021] In some embodiments, the conductive rubber layers of both the first and second surfaces comprise rubber and conductive fillers;

[0022] The rubber includes natural rubber, synthetic rubber, or a blend of natural and synthetic rubber; the synthetic rubber includes one or more of the following blends: styrene-butadiene rubber, butadiene rubber, chloroprene rubber, ethylene propylene rubber, nitrile rubber, hydrogenated nitrile rubber, butyl rubber, chloroprene rubber, polysulfide rubber, fluorosilicone rubber, silicone rubber, or fluororubber; the conductive filler includes one or more of the following: carbon fiber, carbon nanotubes, graphene, carbon black, graphite, silver powder, nickel powder, aluminum powder, iron powder, copper powder, and gold powder.

[0023] The above-mentioned materials combining conductive fillers and rubber have excellent characteristics such as high elasticity, high conductivity, high weather resistance, light weight, high wear resistance, high elongation, high durability, and vibration damping effect.

[0024] In some embodiments, the substrate is preferably made of fiber-reinforced resin material. Fiber-reinforced resin material, as the main material of the board, has advantages such as light weight, fatigue resistance, and high strength.

[0025] In some embodiments, the reinforcing fibers used in the fiber-reinforced resin material include one or more of carbon fiber, glass fiber, aramid fiber, basalt fiber, alumina fiber, or silicon carbide fiber, and the structural form of the reinforcing fibers can be fabric or unidirectional tape.

[0026] In some embodiments, the matrix resin used in the fiber-reinforced resin material includes thermoplastic resin or thermosetting resin. Specifically: the thermoplastic resin may be one or a mixture of several of the following resins: polyetherketone, polysulfone, polyethersulfone, thermoplastic polyimide, polyetherimide, polycarbonate, polyphenylene ether, or polyamide; the thermosetting resin may be one or a mixture of several of the following resins: epoxy resin, bismaleimide resin, thermosetting polyimide resin, polybenzoxazine resin, phenolic resin, cyanate ester resin, or unsaturated polyester resin.

[0027] The combination of the above substrate and conductive rubber layer materials can achieve the following effects: on the one hand, it can give full play to the advantages of fiber-reinforced resin materials, such as high specific strength, specific stiffness, and good structural designability; on the other hand, by coating with conductive rubber layer, the high elasticity of rubber can be used to improve the impact resistance and damping vibration reduction characteristics of the component during service.

[0028] In some embodiments, the conductive element is preferably a metallic conductive element.

[0029] In some embodiments, the conductive rubber layer of the second surface further includes friction-reducing filler, which includes one or a mixture of the following: Si-based particles, Al-based particles, Ti-based particles, Zn-based particles, Cu-based particles, molybdenum-based particles, lead-based particles, and carbon-based particles.

[0030] These fillers can significantly improve the wear resistance of rubber and are readily available. Specifically, materials prepared by adding conductive fillers to rubber or by adding both conductive and wear-resistant fillers simultaneously exhibit excellent electrical conductivity and wear resistance, large tensile deformation, good elongation, and excellent fatigue resistance. They are particularly suitable for complex structural components with special requirements for reciprocating fatigue and large deformation motions, avoiding fatigue damage such as surface cracking caused by the low elongation and relatively weak adhesion of conductive and wear-resistant coatings sprayed on the surface of traditional composite parts.

[0031] Among them, Si-based particles include, but are not limited to, SiO2, Si3N4, and SiC; Al-based particles include, but are not limited to, Al2O3; Ti-based particles include, but are not limited to, TiO2 and TiN; Zn-based particles include, but are not limited to, ZnO; Cu-based particles include, but are not limited to, CuCl, CuCl2, Cu2O, CuO, and CuS; Molybdenum-based particles include, but are not limited to, MoS2; Lead-based particles include, but are not limited to, Pb3O4, PbO, and PbS; and Carbon-based particles include, but are not limited to, carbon nanofibers, graphite, carbon nanotubes, and graphene.

[0032] In some embodiments, the entire area of ​​the first surface and the entire area of ​​the second surface are covered with a conductive rubber layer.

[0033] Alternatively, in some embodiments, the width of the conductive rubber layer covering the first surface in the width direction is 5% to 100% of the width of the substrate.

[0034] Similarly, in the width direction, the width of the conductive rubber layer covering the second surface is 5% to 100% of the width of the substrate.

[0035] A second aspect of the present invention provides a method for preparing the lightning protection composite board described in the first aspect, comprising:

[0036] The substrate with the pre-embedded conductive component and the conductive rubber layer are molded and vulcanized to obtain the lightning protection composite board.

[0037] This method achieves integrated manufacturing of structure and function by one-time vulcanization molding of conductive component embedded composite substrate and conductive rubber layer. It reduces the secondary spraying process required for traditional conductive and wear-resistant composite materials, which helps to improve labor productivity, reduce human and material input, and save production costs.

[0038] A third aspect of the invention provides the use of the lightning protection composite sheet described in the first aspect, wherein the lightning protection composite sheet is used to manufacture a seal for the gap between the main wing, aileron, or flap of an aircraft wing.

[0039] A fourth aspect of the present invention provides a main wing of an aircraft, which is mainly formed of a lightning-resistant composite material as described in the first aspect.

[0040] The fifth aspect of the present invention provides an aileron of an aircraft wing, which is mainly formed of the lightning protection composite material of the first aspect.

[0041] A sixth aspect of the invention provides an aircraft in which the seal between the flaps comprises a lightning protection composite material as described in the first aspect.

[0042] In summary, compared with the prior art, the present invention achieves the following technical effects:

[0043] (1) By embedding a metal part in the second end of the substrate, this end can be used as the active friction end of the plate. This enables the connection of the conductive circuits of the two surfaces (first surface and second surface) of the composite plate, thereby ensuring that the charge can be smoothly discharged from the conductive circuit when the outer surface of the composite plate is subjected to electric loads such as lightning strikes, effectively preventing the problem of open circuit of conductive path caused by the wear of conductive rubber layer at the active friction end.

[0044] (2) The combination of fiber-reinforced resin substrate and conductive rubber layer can achieve the following effects: on the one hand, it gives full play to the advantages of fiber-reinforced resin material, such as high specific strength, high specific stiffness, and good structural designability; on the other hand, by coating with conductive rubber layer, the high elasticity of rubber can be used to improve the impact resistance and damping vibration reduction characteristics of the component during service.

[0045] (3) Materials prepared by adding conductive fillers to rubber or by adding both conductive and wear-resistant fillers have excellent electrical and wear-resistant properties, large tensile deformation, good elongation, and excellent fatigue resistance. They are particularly suitable for complex structural parts with special requirements for reciprocating fatigue and large deformation motion, avoiding fatigue damage such as surface cracking caused by the low elongation and relatively weak adhesion of conductive and wear-resistant coatings sprayed on the surface of traditional composite parts.

[0046] (4) By one-time vulcanization molding of conductive component embedded composite substrate and conductive rubber layer, the structure and function of the structure can be integrated, reducing the secondary spraying process required by traditional conductive and wear-resistant composite materials, which is conducive to improving labor productivity, reducing human and material input, and saving production costs.

[0047] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0048] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0049] Figure 1 This is a schematic diagram of the structure of the substrate in the composite material provided by the present invention;

[0050] Figure 2 This is a schematic diagram of the structure of the composite material provided by the present invention;

[0051] Figure 3 This is a schematic diagram of the assembly of the device for detecting the abrasion and corrosion resistance of the sheet material according to the present invention.

[0052] Figure label:

[0053] 10-Substrate, 101-First end, 102-Second end, 103-First surface, 104-Second surface, 105-Conductive component, 20-Conductive rubber layer, 30-Conductive rubber layer. Detailed Implementation

[0054] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0056] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0057] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0058] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0059] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0060] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0061] To address the problem of open conductive paths in composite materials used in aircraft due to abrasion caused by deflection and friction during operation, this invention provides... Figure 1 and Figure 2 The composite panel structure shown has functions such as lightning protection, wear resistance, and vibration reduction.

[0062] Combination Figure 1 and Figure 2 As shown, the composite board includes a substrate 1, which has a first end 101 and a second end 102 disposed opposite to each other, and at least one conductive element 105 is embedded in the second end 102 of the substrate 1.

[0063] The substrate 1 has a first surface 103 and a second surface 104 disposed opposite to each other. The first surface 103 and the second surface 104 extend from the first end 101 to the second end 102 respectively. The conductive element 105 extends from the first surface 103 to the second surface 104.

[0064] At least a portion of the first surface 103 and at least a portion of the second surface 104 are respectively covered with a conductive rubber layer 20 and a conductive rubber layer 30, and the conductive rubber layer 20 covering the first surface 103 extends at least from the first end 101 to the second end 102, and the conductive rubber layer 30 covering the second surface 104 extends at least from the first end 101 to the second end 102.

[0065] Therefore, by embedding a conductive element 105 in the second end 102 of the substrate 1, this end can serve as the movable friction end of the plate. This enables the connection of the conductive circuits of the two surfaces (first surface 103 and second surface 104) of the composite plate, thereby ensuring that when the outer surface of the composite plate is subjected to electrical loads such as lightning strikes, the charge can be smoothly discharged through the conductive circuit, effectively preventing the problem of open circuit of conductive path caused by the wear of conductive rubber layer at the movable friction end face.

[0066] like Figure 1 As shown, multiple conductive elements 105 can be provided. The multiple conductive elements 105 are distributed at equal intervals along the length direction.

[0067] The length direction, width direction, and thickness direction in this document are defined as follows: The width direction W of the substrate 1 extends from the first end 101 to the second end 102; the thickness direction of the substrate 1 extends from the first surface 103 to the second surface 104; and the length direction L is perpendicular to both the first and second directions. The composite material provided by this invention can be a flat panel or a curved panel, such as... Figure 1 and 2 The examples listed are curved sheet materials, so their width direction will vary depending on the position of the first surface 103, but the overall direction remains unchanged, that is, basically from the first end 101 to the second end 102. At the same time, the length direction is fixed, and the other two-dimensional directions perpendicular to it (width direction and thickness direction) are correspondingly fixed.

[0068] The equal spacing of multiple conductive components 105 can not only meet the requirements of circuit conduction on both sides of the substrate 1, but also achieve weight reduction. At the same time, the conductivity of the composite board is evenly distributed, which helps to extend its service life.

[0069] Since the density of conductive elements 105 is generally greater than that of substrate 1, the size of conductive elements 105 does not need to be too large, as long as it can effectively conduct the circuit. Therefore, in some embodiments, the side length of conductive elements 105 along the width direction is 5% to 20% of the width of substrate 1. For the same purpose, the sum of the side lengths of all conductive elements 105 along the length direction can be 5% to 20% of the length of substrate 1.

[0070] In some embodiments, the two opposing surfaces of all conductive elements 105 are flush with the first surface 103 and the second surface 104, respectively. The flush alignment of the conductive elements 105 with the substrate 1 surface reduces wind resistance and maintains the regularity of the material's shape.

[0071] In some embodiments, the conductive element 105 is block-shaped.

[0072] In some implementations, all conductive elements 105 have the same shape and size.

[0073] In some embodiments, the entire area of ​​the first surface 103 and the entire area of ​​the second surface 104 are covered with a conductive rubber layer.

[0074] Alternatively, in some embodiments, the width of the conductive rubber layer covering the first surface 103 in the width direction is 5% to 100% of the width of the substrate 1.

[0075] Similarly, in the width direction, the width of the conductive rubber layer covering the second surface 104 is 5% to 100% of the width of the substrate 1.

[0076] The following examples are used to illustrate the present invention, but the present invention is not limited thereto.

[0077] Example 1

[0078] Producing lightning protection composite material sheets with wear resistance, vibration reduction, and conductivity: length 500mm±5mm, width 100mm±5mm, thickness 4.2mm±0.2mm, the steps are as follows.

[0079] 1. Lay a 3mm±0.2mm thick T300 carbon fiber twill fabric / epoxy resin composite material preform, and uniformly embed three copper metal blocks along the length of the moving friction end. The thickness of the copper metal blocks is the same as that of the moving friction end, with a length of 50mm±2mm and a width of 10mm±2mm. The composite material substrate is prepared by vacuum bag pressing process.

[0080] 2. Grind both sides of the composite material substrate and clean with alcohol. Apply adhesive to both sides of the substrate to prepare an adhesive layer. The adhesive layer thickness is 0.05mm to 0.1mm.

[0081] 3. Starting from the moving friction end of the composite material substrate, a 0.5mm ± 0.1mm thick hydrogenated nitrile butadiene elastic adhesive layer is applied to the friction side surface, containing Al2O3 particle wear-resistant filler and silver powder conductive filler (i.e., Figure 1The second surface of the composite material has a length and width equivalent to the free end of the composite material's moving friction. A 0.5mm ± 0.1mm thick hydrogenated nitrile rubber layer with silver powder conductive filler is adhered to the adhesive layer on the other side of the composite material substrate. The blank formed from the composite material substrate, adhesive, elastic conductive rubber layer, and elastic wear-resistant conductive rubber layer is then molded and vulcanized at 150 ± 5℃, 10 ± 5MPa, and 2 ± 0.5h. After demolding and trimming, a lightning protection composite material sheet of uniform thickness with wear resistance, vibration damping, and conductivity is obtained.

[0082] Example 2

[0083] Producing lightning protection composite panels with wear resistance, vibration reduction, and conductivity: length 1270mm±5mm, width 150mm±5mm, thickness 3.6mm±0.2mm, the steps are as follows.

[0084] 1. Lay a 2.5mm±0.2mm thick T800 carbon fiber plain weave fabric / bismaleimide resin composite material preform, and evenly embed five metal copper blocks along the length of the moving friction end. The thickness of the copper blocks is the same as that of the moving friction end, with a length of 80mm±2mm and a width of 20mm±2mm. Prepare the composite material substrate by autoclaving.

[0085] 2. Grind both sides of the composite material substrate and clean with alcohol. Apply adhesive to both sides of the substrate to prepare an adhesive layer. The adhesive layer thickness is 0.05mm to 0.1mm.

[0086] 3. Starting from the moving friction end of the composite material substrate, a 0.6mm±0.1mm thick natural rubber elastic adhesive layer with MoS2 particle wear-resistant filler and silver powder conductive filler is applied to the friction side surface. Its length is equivalent to the free end of the moving friction of the composite material, and its width is 50% of the width of the composite material. On the other side of the composite material substrate, a 0.4mm±0.1mm thick natural rubber elastic adhesive layer with graphene conductive filler is applied to the adhesive layer. Its length and width are equivalent to the free end of the moving friction of the composite material. The blank formed by the composite material substrate, adhesive, elastic conductive rubber layer, and elastic wear-resistant conductive rubber layer is molded and vulcanized at 145±5℃, 10±5MPa, and 2±0.75h. After demolding and trimming, a lightning protection composite curved surface sheet with wear resistance, vibration damping, and conductivity is obtained.

[0087] The abrasion and corrosion resistance of all the above embodiments was tested using the following methods.

[0088] The first end 101 of the lightning protection composite material of the present invention is connected and fixed (e.g., Figure 3 On the left, simulating a fixed wing surface), the second end 102 is attached to the rotating module (e.g., Figure 3 On the right side (simulating an active wing surface), the rotating module rotates between -45° and +45° along the central rotation axis. The second end of the composite material plate slides and rubs on the rotating module. The upper surface of the rotating module is coated with primer, infrared, wave-absorbing and wear-resistant coatings to simulate the state of an aircraft wing surface. After a certain number of reciprocating sliding frictions, the wear condition of the second end of the composite material curved panel is observed.

[0089] After deflection wear test, in both Examples 1 and 2, after 100,000 deflection friction tests at room temperature, the second-end composite material substrate was not worn through and exposed, showing good wear and corrosion resistance.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A lightning strike protection composite panel, characterized by, The substrate includes a first end and a second end disposed opposite to each other, and at least one conductive element is embedded in the second end of the substrate. The substrate has a first surface and a second surface disposed opposite to each other, the first surface and the second surface extending from the first end to the second end respectively, and the conductive element penetrating from the first surface to the second surface; At least a portion of the first surface and at least a portion of the second surface are covered with a conductive rubber layer, and the conductive rubber layer covering the first surface extends at least from the first end to the second end, and the conductive rubber layer covering the second surface extends at least from the first end to the second end.

2. The lightning strike resistant composite panel of claim 1, wherein, Includes multiple conductive components; The width direction of the substrate extends from the first end to the second end, the thickness direction extends from the first surface to the second surface, and the length direction of the substrate is perpendicular to both the width and thickness directions. The plurality of conductive elements are distributed at equal intervals along the length direction.

3. The lightning strike resistant composite panel of claim 2, wherein, The side length of the conductive element along the width direction is 5% to 20% of the width of the substrate.

4. The lightning strike resistant composite panel of claim 2, wherein, The sum of the side lengths of all the conductive elements along the length direction is 5% to 20% of the length of the substrate.

5. The lightning protection composite board as described in claim 1, characterized in that, The two opposing surfaces of all the conductive elements are flush with the first surface and the second surface, respectively.

6. The lightning protection composite board as described in claim 1, characterized in that, The conductive rubber layers on both the first and second surfaces contain rubber and conductive fillers; The rubber includes natural rubber, synthetic rubber, or a blend of natural and synthetic rubber; the synthetic rubber includes one or more blends of styrene-butadiene rubber, cis-butadiene rubber, chloroprene rubber, ethylene propylene rubber, nitrile rubber, butyl rubber, chloroprene rubber, polysulfide rubber, fluorosilicone rubber, silicone rubber, and fluororubber; the conductive filler includes one or more mixtures of carbon fiber, carbon nanotubes, graphene, carbon black, graphite, silver powder, nickel powder, aluminum powder, iron powder, copper powder, and gold powder. The substrate is made of fiber-reinforced resin material; the conductive component is a metal conductive component.

7. The lightning protection composite board as described in claim 6, characterized in that, The conductive rubber layer on the second surface also includes friction-reducing fillers, which include one or more of the following: Si-based particles, Al-based particles, Ti-based particles, Zn-based particles, Cu-based particles, molybdenum-based particles, lead-based particles, and carbon-based particles.

8. The lightning protection composite board as described in claim 1, characterized in that, The entire area of ​​the first surface and the entire area of ​​the second surface are covered with a conductive rubber layer.

9. The method for preparing the lightning protection composite board according to any one of claims 1-8, characterized in that, include: The substrate with the pre-embedded conductive component and the conductive rubber layer are molded and vulcanized to obtain the lightning protection composite board.

10. The use of the lightning protection composite board according to any one of claims 1-8, characterized in that, The lightning protection composite material is used to manufacture seals for the gaps between the main wing, aileron, or flaps of an aircraft wing.

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