Graphene capsule, honeycomb core wave-absorbing material and preparation method of graphene capsule and honeycomb core wave-absorbing material

Abstract

The invention relates to the field of composite materials, in particular to a graphene capsule, a honeycomb core wave-absorbing material and a preparation method thereof. The graphene capsule comprises a capsule shell and a filler, the capsule shell is prepared from a wave-transparent material, and the filler is a graphene powder material. The honeycomb core wave-absorbing material comprises a honeycomb core, and the honeycomb core is filled with the graphene capsule. The graphene capsules are adopted as the filler, the wave-absorbing performance and parameters of the single capsule are relatively more stable, the designability of the wave-absorbing performance of the honeycomb core is higher, and the adjustable range of the wave-absorbing performance is wider. According to the preparation process of the honeycomb core wave-absorbing material, mechanical equipment can be adopted for filling capsules, operation is more standardized, and the designability of the filling process is higher. Meanwhile, the wave-absorbing material of the honeycomb core is higher in maintainability, and when the wave-absorbing material is damaged, only the damaged graphene capsule needs to be independently repaired and replaced.

Description

Technical Field

[0001] The present application relates to the field of composite materials, and in particular to a graphene capsule, a honeycomb core absorbing material and a preparation method thereof. Background Art

[0002] Graphene is a two-dimensional material with excellent electrical and thermal conductivity. According to recent research, graphene also has special wave-absorbing properties. Wave-absorbing properties are the key to stealth technology, and the introduction of wave-absorbing materials into stealth technology is also a research hotspot at home and abroad.

[0003] Authorized Chinese patent CN 114030269 B discloses a method for manufacturing a graphene-filled honeycomb core absorbing composite material, which involves directly filling the core cells of the honeycomb core material with graphene powder materials of different contents or different components. By changing the structure of the honeycomb core material or adjusting the composition and content of the filled graphene powder material, a graphene powder-filled honeycomb core absorbing composite material that meets the requirements of various absorbing frequency bands can be produced.

[0004] However, the above patent directly fills the honeycomb core with graphene powder, which has the technical problem of difficult powder filling construction. Summary of the invention

[0005] The main purpose of the present application is to provide a graphene capsule, a honeycomb core absorbing material and a preparation method thereof, aiming to solve the problems of the difficulty in graphene powder filling construction and the uncontrollable powder in the honeycomb core in the prior art.

[0006] To achieve the above-mentioned purpose, the present application proposes a graphene capsule, which includes a capsule shell and a filler. The capsule shell is made of a wave-transmitting material, and the filler is a graphene powder material.

[0007] Optionally, the wave-transmitting material includes at least one of a glass fiber composite material, a ceramic-based composite material and an organic wave-transmitting material.

[0008] Optionally, the graphene powder material includes at least one of pure graphene powder and composite powder, and the composite powder includes graphene powder and magnetic particles.

[0009] Optionally, the length of the capsule shell is 0.5 to 20 mm.

[0010] Optionally, the thickness of the capsule shell is 0.01 to 0.1 mm.

[0011] Based on the same inventive concept, the present application also provides a method for preparing the above-mentioned graphene capsule, comprising the steps of:

[0012] According to the wave absorbing performance requirements of the graphene capsule, the capsule shell is designed using electromagnetic wave material performance simulation software to determine the material and size parameters of the capsule shell;

[0013] Prepare a capsule shell according to the determined material and size parameters;

[0014] The graphene powder material is filled into the capsule shell to obtain a graphene capsule.

[0015] Based on the same inventive concept, the present application also provides a honeycomb core absorbing material, comprising at least one layer of honeycomb core, wherein the honeycomb core is filled with the above-mentioned graphene capsules.

[0016] Optionally, a core cell height of the honeycomb core is greater than or equal to a length of the graphene capsule.

[0017] Optionally, the honeycomb core absorbing material further comprises a skin, an adhesive film and a composite board;

[0018] One side of the honeycomb core is connected to the skin through the adhesive film, and the other side of the honeycomb core is connected to the composite board through the adhesive film.

[0019] Based on the same inventive concept, the present application also provides a method for preparing the above-mentioned honeycomb core absorbing material, comprising the steps of:

[0020] Cut the skin to the required size and use adhesive film to bond the honeycomb core to the skin;

[0021] Filling the graphene capsules in the honeycomb core cells manually or mechanically;

[0022] After the graphene capsules are filled, the surface of the honeycomb core is covered with a film, and then with a composite board, and the whole is placed in an autoclave for curing to obtain a honeycomb core absorbing material.

[0023] Compared with the prior art, the beneficial effects achieved by this application are:

[0024] Compared with the direct filling of graphene powder in the previous authorized patent CN 114030269 B, the present invention proposes an improved solution and provides a graphene capsule. The graphene capsule is used as a filler. The wave absorption performance and parameters of a single capsule are relatively more stable, and the wave absorption performance of the honeycomb core is more designable. There are more adjustable content performance parameters, capsule geometric parameters, and filling compatibility forms, so the wave absorption performance can be adjusted in a wider range.

[0025] Due to the change in the filling method of graphene, the preparation method of honeycomb core absorbing materials can be changed from the original manual filling of powder to filling capsules by mechanical equipment. The operation is more standardized and the filling process is more designable.

[0026] Compared with directly filling the honeycomb core with graphene powder, filling in the form of capsules is more maintainable. When the absorbing material is damaged, the damaged graphene capsules can be repaired and replaced separately. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0028] Figure 1 It is a schematic diagram of directly filling the honeycomb core with graphene powder in the prior art;

[0029] Figure 2 This is a schematic diagram of the capsule shell structure in the embodiment of the present application;

[0030] Figure 3 This is a schematic diagram of graphene capsules filled in the honeycomb core cells in the embodiment of the present application;

[0031] Figure 4 This is a photo of the honeycomb core after being attached with adhesive film in Example 4 of the present application;

[0032] Figure 5 This is a graph showing the RCS wave absorption performance of the honeycomb core sample of Example 4;

[0033] Figure 6 This is a graph showing the RCS wave absorption performance of the honeycomb core sample of Example 5;

[0034] Figure 7 This is a curve diagram of the RCS wave absorption performance of the honeycomb core sample of Example 6;

[0035] Figure 8 This is a graph showing the RCS wave absorption performance of the honeycomb core sample of Example 7;

[0036] Reference numerals:

[0037] 1-Core grid, 2-Graphene capsule.

[0038] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0041] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0042] Honeycomb core structure absorbing materials have become important materials in the fields of wireless communication and radar technology due to their unique composite structure and material composition. Honeycomb core structure absorbing materials are designed using the shape of the honeycomb, and better absorbing effects can be obtained by adjusting the geometric parameters of the honeycomb structure. Traditional honeycomb core structure preparation methods often require the addition of conductive particles or metal magnetic powders to improve absorbing performance. With the in-depth study of the radar wave absorbing properties of graphene and its derivatives, the application of graphene in honeycomb cores has gradually become a popular research direction.

[0043] In current research in this field, a process scheme is usually adopted to produce a honeycomb core product with a graphene coating by coating a graphene slurry or a rubber on the surface of the honeycomb core to form a coating, and finally drying and post-processing to form a honeycomb core composite material with a graphene coating.

[0044] The previous invention CN 114030269 B discloses a method for manufacturing a graphene-filled honeycomb core absorbing composite material, which involves directly filling a core cell 1 of a honeycomb core material with graphene powder materials of different contents or different components, and manufacturing a graphene powder-filled honeycomb core absorbing composite material that meets the requirements of multiple absorbing frequency bands by changing the structure of the honeycomb core material or the composition and content of the filled graphene powder materials. The graphene powder is directly filled into the honeycomb core cell 1, such as Figure 1 This technology has many problems in the specific construction process, such as: difficult construction of powder filling, poor uniformity of powder filling, uncontrollable movement of powder in the honeycomb core, etc. These problems will lead to uncontrollable absorbing performance of the final absorbing material and fail to meet the design requirements.

[0045] In view of the technical problems existing in the above-mentioned prior art, the first embodiment of the present application provides a graphene capsule 2, wherein the graphene capsule 2 comprises a capsule shell and a filler, wherein the capsule shell is made of a wave-transmitting material, and the filler is a graphene powder material.

[0046] This application pre-fills a small amount of graphene powder with different wave-absorbing properties into a capsule made of wave-transmitting material with standardized size specifications, and then uses a filling capsule with different wave-absorbing properties to re-fill the honeycomb core material. Since the capsule is small in size, the amount of graphene powder that can be accommodated is limited, and the size can be standardized, the filling of the powder can be completed mechanically and automatically, effectively solving the series of problems mentioned above.

[0047] As an optional implementation, the wave-transmitting material includes at least one of a glass fiber composite material, a ceramic-based composite material and an organic wave-transmitting material.

[0048] Glass fiber is light in weight and has good hoop strength; it has excellent electrical insulation and strong wave transmittance (wave transmittance is as high as over 98%).

[0049] Ceramic-based composite materials are a type of absorbing materials made of ceramic materials as the matrix and adding absorbing agents. The ceramic matrix has good thermal stability, chemical stability, high mechanical strength and wave transmission, and is often used as a composite matrix or impedance matching layer. In addition to maintaining reliable absorbing capabilities under extreme environments such as high temperature and high pressure, ceramic-based composite materials may also achieve strong load-bearing capacity. They mainly include carbide ceramic-based absorbing materials, nitride ceramic-based absorbing materials, and oxide ceramic-based absorbing materials.

[0050] Organic wave-transmitting materials are composite materials that have both load-bearing capacity and electromagnetic wave transmission functions, with organic high molecular polymers as the matrix and inorganic or organic fibers as the reinforcement material, and are formed by hot pressing, winding, resin transfer molding or sintering. Commonly used organic high molecular polymers include polyimide, polytetrafluoroethylene, cyanate ester and silicone resin.

[0051] As an optional implementation, the graphene powder material includes at least one of pure graphene powder and composite powder, and the composite powder includes graphene powder and magnetic particles.

[0052] As an optional embodiment, the pure graphene powder material may be one or more of flocculent graphene, expanded graphene or conventional mechanically exfoliated graphene.

[0053] Since the capsules are small in size and standardized, they can be filled and manufactured in large quantities using the mature technology of existing drug capsule filling, and mechanized and automated production can be easily achieved.

[0054] Based on the same inventive concept, the present application also provides a method for preparing the above-mentioned graphene capsule, comprising the steps of:

[0055] According to the wave absorbing performance requirements of the graphene capsule, the capsule shell is designed using electromagnetic wave material performance simulation software to determine the material and size parameters of the capsule shell;

[0056] Prepare a capsule shell according to the determined material and size parameters;

[0057] Specifically, after determining the size parameters of the capsule shell, a capsule mold is first prepared according to the size parameters; the corresponding material is injected or coated in the capsule mold, and the capsule shell is obtained after curing. The capsule shell is composed of a capsule body and a capsule cap, so the corresponding capsule mold also includes a capsule body mold and a capsule cap mold.

[0058] The graphene powder material is filled into the capsule body, and then a capsule cap is installed to obtain a graphene capsule.

[0059] like Figure 2 As shown, as an example, using the geometric features of conventional medicinal capsules, the cylindrical diameter (D) of the capsule shell should be smaller than the inscribed circle diameter of the hexagonal grid of the filled honeycomb core lattice 1, for example: the inscribed circle diameter of the -2.75 specification honeycomb core is 4.763mm, and the inscribed circle diameter of the -1.83 specification honeycomb core is 3.17mm. The overall length of the capsule is designed as a standardized series of length dimensions (L), so as to achieve the adjustability of the capsule's wave absorbing performance in the length direction. The size and shape of the capsule shell can be specially designed and manufactured according to the size of the core lattice 1 (honeycomb hole) of the honeycomb core material to be filled later, and is not limited to the following. Figure 2 The geometry shown.

[0060] As an optional embodiment, the length of the capsule shell is 0.5-20 mm. As an example, the length of the capsule shell is 0.5 mm, 1 mm, 2 mm, 3 mm, 5 mm, 10 mm or 20 mm.

[0061] As an optional embodiment, the thickness of the capsule shell is 0.01-0.1 mm. As an example, the thickness of the capsule shell is 0.01, 0.03, 0.05, 0.07, 0.09 or 0.1 mm.

[0062] Based on the same inventive concept, another embodiment of the present application provides a honeycomb core absorbing material, comprising a honeycomb core, wherein the honeycomb core is filled with the graphene capsules 2 of the above embodiment.

[0063] As an optional embodiment, the height of the core cell 1 of the honeycomb core is greater than or equal to the length of the graphene capsule 2, that is, the selection and matching of the size of the graphene capsule 2 should ensure that the upper and lower surfaces of the honeycomb core cell 1 in the actual structure do not protrude, so as to facilitate the subsequent covering with skin or film.

[0064] As an optional implementation, the honeycomb core absorbing material further includes a skin, an adhesive film and a composite board;

[0065] One side of the honeycomb core is connected to the skin through the adhesive film, and the other side of the honeycomb core is connected to the composite board through the adhesive film.

[0066] As an optional implementation, the composite board is a cured quartz fiber board.

[0067] As an optional implementation, the honeycomb core material is aramid paper honeycomb, ferrite honeycomb or a hybrid honeycomb in which the two are stacked.

[0068] As an optional implementation, the aramid paper honeycomb may be an NH aramid honeycomb.

[0069] In this application, the comprehensive wave absorption performance of the composite material is determined by the characteristics of the graphene material itself, the filling content, density, the height of the filled honeycomb core and other parameters combined with the size, quantity and distribution of the capsules. The adjustable content performance parameters, capsule geometric parameters and filling compatibility forms are more, so the wave absorption performance can be adjusted in a wider range. And the use of standardized capsules for filling can ensure the uniformity of graphene distribution and avoid the uncontrollable defects of direct filling of powder.

[0070] Based on the same inventive concept, another embodiment of the present application provides a method for preparing the above-mentioned honeycomb core absorbing material, comprising the steps of:

[0071] S1. Cut the skin to the required size and use adhesive film to bond the honeycomb core to the skin;

[0072] S2, filling the graphene capsules 2 in the honeycomb core cells 1 manually or mechanically;

[0073] S3. After the graphene capsules 2 are filled, the surface of the honeycomb core is covered with a film, and then covered with a composite board, and the whole is put into an autoclave for curing to obtain a honeycomb core absorbing material.

[0074] As an optional embodiment, in step S2, according to the design of the wave absorbing performance of the honeycomb core wave absorbing material, graphene capsules 2 of different sizes and quantities are filled in the honeycomb core cells 1 according to the design parameters. Figure 3, so that the components show more complex wave-absorbing performance. Compared with the existing technology of directly using graphene powder filling, this feature has stronger processability, better operability and more flexible combination. Figure 3 The honeycomb core in the figure is shown in the form of an oblique section to clearly show that each core cell 1 can be filled with graphene capsules 2 of different numbers and sizes. This does not mean that the graphene capsules 2 will exceed the upper and lower surfaces of the honeycomb core. As an optional embodiment, according to the requirements of the absorbing performance of the honeycomb core absorbing material, CST

[0075] Studio Suite and other electromagnetic simulation analysis software and electromagnetic wave material performance simulation software are used to design the capsule shell and determine the material and size parameters of the capsule shell. By adjusting the parameters of the graphene capsule itself and its distribution in the core grid of the honeycomb core material, the wave absorption performance of the overall structure is adjusted and verified. This designability is stronger and more flexible than existing technologies.

[0076] The graphene capsule 2 of standardized design and manufacturing proposed in the present invention has a smaller volume and, compared with powders filled unevenly and over a large area, has simpler and more consistent performance, is more standardized and more adjustable, and can meet the requirements of different absorbing frequency bands.

[0077] The present invention proposes a honeycomb core absorbing material filled with graphene capsules 2 and a manufacturing technology thereof, which replaces the prior art solution of directly filling the honeycomb core with graphene powder, and can not only achieve a significant reduction in product weight, but also avoid the disadvantage that traditional absorbing materials need to be frequently replaced, and have stronger maintainability. When the absorbing structural material is damaged, the damaged graphene capsules can be repaired and replaced separately, and the material has higher designability and adjustability.

[0078] The manufacturing process technology proposed in the present invention is simpler than that of patent CN 114030269 B, and the process control is easier, and can form industrial transformation faster. Moreover, the process does not involve toxic and harmful operations and is safe and reliable.

[0079] Some specific embodiments are provided below. In the following embodiments, the flocculent graphene used is brand SG-01005; the expanded graphene is brand XFI14; the conventional mechanically exfoliated graphene is brand XFQ024; the ferrite honeycomb is model skuf; and the aramid paper honeycomb is model NH-1-2.75-64.

[0080] Example 1

[0081] A graphene capsule 2, comprising a capsule shell and a filler;

[0082] The capsule shell is made of a nitride ceramic-based composite material and has a diameter of 3 mm, a length of 5 mm, and a thickness of 0.06 mm.

[0083] The filler is graphene powder material, which is pure graphene powder, specifically flocculent graphene, and the filling amount of graphene powder in each capsule shell is 0.85mg to 1.5mg. 。

[0084] Example 2

[0085] A graphene capsule 2, comprising a capsule shell and a filler;

[0086] The capsule shell is made of glass fiber composite material and has a diameter of 4 mm, a length of 10 mm and a thickness of 0.1 mm.

[0087] The filler is a graphene powder material, which is a mixed powder of pure graphene powder and magnetic particles, wherein the pure graphene powder accounts for 60% by mass, specifically expanded graphene, and the magnetic particles account for 40% by mass, specifically magnetic iron oxide; the filling amount of the powder in each capsule shell is 5.5mg to 9.5mg 。

[0088] Example 3

[0089] A graphene capsule 2, comprising a capsule shell and a filler;

[0090] The capsule shell is made of an organic composite material with a diameter of 2 mm, a length of 3 mm and a thickness of 0.03 mm. The organic composite material has epoxy resin as a matrix and quartz fiber as a reinforcing material.

[0091] The filler is graphene powder material, which is pure graphene powder, and the graphene is specifically peeled off by conventional machinery; the filling amount of the powder in each capsule shell is 0.25mg to 0.45mg 。

[0092] Example 4

[0093] A honeycomb core absorbing material comprises a honeycomb core, wherein the honeycomb core is filled with the graphene capsules 2 of Example 1.

[0094] The honeycomb core is an aramid paper honeycomb with a honeycomb size of 200×200 mm. The inscribed circle diameter of the core cell 1 is 3.17 mm and the height is 12 mm. Two graphene capsules 2 in Example 1 are filled in each core cell 1 .

[0095] One side of the honeycomb core is covered with a skin by bonding with an adhesive film, and the other side is covered with a quartz fiberboard by bonding with an adhesive film.

[0096] The photo of the honeycomb core after the adhesive film is applied to Example 4 is as follows Figure 4 As shown in the figure, the measured data of the RCS absorbing performance of the sample is as follows Figure 5shown.

[0097] Example 5

[0098] A honeycomb core absorbing material comprises a three-layer honeycomb core, wherein the honeycomb core is filled with graphene capsules 2.

[0099] The first layer of honeycomb core is aramid paper honeycomb, which serves as the incident surface of the absorbing material; the honeycomb size is 200×200 mm, the inscribed circle diameter of the core cell 1 is 4.763 mm, and the height is 20 mm. Three graphene capsules 2 in Example 2 are filled in each core cell 1.

[0100] The second layer of honeycomb core is a ferrite honeycomb with a honeycomb size of 200×200 mm. The inscribed circle diameter of the core cell 1 is 4.763 mm and the height is 20 mm. No graphene capsules 2 are filled therein.

[0101] The third layer of honeycomb core is an aramid paper honeycomb, which serves as a reflective surface of the absorbing material; the honeycomb size is 200×200 mm, the inscribed circle diameter of the core cell 1 is 4.763 mm, and the height is 15 mm. One graphene capsule 2 in Example 2 and one graphene capsule 2 in Example 3 are filled in each core cell 1.

[0102] The three-layer honeycomb core is bonded to each other as a whole through adhesive film. One side of the whole honeycomb core is covered with a skin through adhesive film, and the other side is covered with a quartz fiber board through adhesive film.

[0103] The measured data of the RCS wave absorption performance of the honeycomb core sample of Example 5 is as follows: Figure 6 shown.

[0104] Example 6

[0105] A honeycomb core wave absorbing material comprises two layers of honeycomb cores, wherein the honeycomb cores are filled with graphene capsules 2.

[0106] The first layer of honeycomb core is an aramid paper honeycomb with a honeycomb size of 180×180 mm, an inscribed circle diameter of the core cell 1 of 4.763 mm, and a height of 20 mm; the first layer of honeycomb core is divided into three areas from the center to the periphery according to equal areas, the center is a high-quantity area, the middle area is a medium-quantity area, and the edge is a low-quantity area; each core cell 1 in the high-quantity area is filled with four graphene capsules 2 in Example 1; each core cell 1 in the medium-quantity area is filled with one graphene capsule 2 in Example 2 and one graphene capsule 2 in Example 3; each core cell 1 in the low-quantity area is filled with two graphene capsules 2 in Example 3;

[0107] The honeycomb core obtained by the above filling method has a graphene filling amount that decreases step by step from the center to the edge, and can show more complex wave absorbing performance.

[0108] The second layer of honeycomb core is a ferrite honeycomb with a honeycomb size of 180×180 mm. The inscribed circle diameter of the core cell 1 is 4.763 mm and the height is 10 mm. No graphene capsules 2 are filled therein.

[0109] The two layers of honeycomb core are bonded to each other as a whole through adhesive film. One side of the whole honeycomb core is covered with a skin through adhesive film, and the other side is covered with a quartz fiber board through adhesive film.

[0110] The measured data of the RCS wave absorption performance of the honeycomb core sample of Example 6 are as follows: Figure 7 shown.

[0111] Example 7

[0112] A honeycomb core absorbing material comprises a three-layer honeycomb core, wherein the honeycomb core is filled with graphene capsules 2.

[0113] The first layer of honeycomb core is an aramid paper honeycomb with a honeycomb size of 180×180 mm, an inscribed circle of a core cell 1 with a diameter of 3.17 mm and a height of 20 mm; the first layer of honeycomb core is divided into 5 regions of equal area from left to right, which are sequentially arranged as regions 1 to 5; each core cell 1 in the first region is filled with 4 graphene capsules 2 in Example 1; each core cell 1 in the second region is filled with 2 graphene capsules 2 in Example 1 and 3 graphene capsules 2 in Example 3; each core cell 1 in the third region is filled with 2 graphene capsules 2 in Example 1 and 2 graphene capsules 2 in Example 3; each core cell 1 in the fourth region is filled with 2 graphene capsules 2 in Example 1 and 1 graphene capsule 2 in Example 3; each core cell 1 in the fifth region is filled with 1 graphene capsule 2 in Example 1 and 1 graphene capsule 2 in Example 3;

[0114] The honeycomb core obtained by the above filling method has a graphene filling amount that decreases step by step from left to right.

[0115] The second layer of honeycomb core is an aramid paper honeycomb with a honeycomb size of 180×180 mm. The inscribed circle diameter of the core cell 1 is 4.763 mm and the height is 10 mm. One graphene capsule 2 in Example 2 is filled in each core cell 1 .

[0116] The third layer of honeycomb core is a ferrite honeycomb with a honeycomb size of 180×180 mm. The inscribed circle diameter of the core cell 1 is 3.17 mm and the height is 5 mm. One graphene capsule 2 in Example 3 is filled in each core cell 1 .

[0117] The three-layer honeycomb core is bonded to each other as a whole through adhesive film. One side of the whole honeycomb core is covered with a skin through adhesive film, and the other side is covered with a quartz fiber board through adhesive film.

[0118] The measured data of the RCS wave absorption performance of the honeycomb core sample of Example 7 is as follows: Figure 8 shown.

[0119] Example 8

[0120] A method for preparing a honeycomb core absorbing material comprises the following steps:

[0121] S1. Prepare the skin in advance and cut it to the required size. Use a honeycomb core with a size of 200×200mm, that is, cut the skin to 200×200mm. Use adhesive film to bond the honeycomb core to the skin;

[0122] S2, filling the graphene capsule 2 in the honeycomb core cell 1;

[0123] The honeycomb core is an aramid paper honeycomb with a honeycomb size of 200×200 mm. The inscribed circle diameter of the core cell 1 is 3.17 mm and the height is 12 mm. Two graphene capsules 2 in Example 1 are filled in each core cell 1 using automated mechanical equipment.

[0124] S3. After the graphene capsules 2 are filled, the surface of the honeycomb core is covered with a film, and then covered with a cured quartz fiber board, and the whole is placed in an autoclave for curing.

[0125] S4. After the overall curing is completed, the material is taken out, and a carbon fiber composite board and a glass fiber composite board are respectively glued on both sides of the material to obtain a honeycomb core absorbing material.

[0126] Example 9

[0127] A method for preparing a honeycomb core absorbing material comprises the following steps:

[0128] S1. Prepare the skin in advance and cut it to the required size. This embodiment uses a honeycomb core with a size of 180×180mm, that is, cut the skin into 180×180mm. Use adhesive film to bond the second layer of honeycomb core to the skin; the second layer of honeycomb core is a ferrite honeycomb with a honeycomb size of 180×180mm, and the inscribed circle diameter of the core cell 1 is 4.763mm and the height is 10mm.

[0129] S2, filling the graphene capsule 2 in the honeycomb core cell 1;

[0130] The second layer of honeycomb core is not filled with graphene capsules 2, but directly covered with a layer of adhesive film on its surface, and then the first layer of honeycomb core is stacked on it;

[0131] The first layer of honeycomb core is an aramid paper honeycomb with a honeycomb size of 180×180mm, a core cell 1 with an inscribed circle diameter of 4.763mm and a height of 20mm. The first layer of honeycomb core is divided into three regions from the center to the periphery with equal areas, the center is the high-volume region, the middle region is the medium-volume region, and the edge is the low-volume region; each core cell 1 in the high-volume region is filled with four graphene capsules 2 in Example 1; each core cell 1 in the medium-volume region is filled with one graphene capsule 2 in Example 2 and one graphene capsule 2 in Example 3; each core cell 1 in the low-volume region is filled with two graphene capsules 2 in Example 3;

[0132] S3. After the graphene capsules 2 of the first layer of honeycomb core are filled, the surface of the first layer of honeycomb core is covered with a film, and then covered with a cured quartz fiber board, and the whole is placed in an autoclave for curing.

[0133] S4. After the overall solidification is completed, the material is taken out to obtain a honeycomb core absorbing material.

[0134] Example 10

[0135] S1. Prepare the skin in advance and cut it to the required size. This embodiment uses a honeycomb core with a size of 180×180mm, that is, cut the skin into 180×180mm. Use adhesive film to bond the third layer of honeycomb core to the skin; the third layer of honeycomb core is a ferrite honeycomb with a honeycomb size of 180×180mm, and the inscribed circle diameter of the core cell 1 is 3.17mm and the height is 5mm.

[0136] S2, filling the graphene capsule 2 in the honeycomb core cell 1;

[0137] Each core cell 1 of the third layer of honeycomb core is filled with one graphene capsule 2 of Example 3. After the filling is completed, a layer of adhesive film is covered thereon, and then the second layer of honeycomb core is stacked.

[0138] The second layer of honeycomb core is an aramid paper honeycomb with a honeycomb size of 180×180 mm, a core cell 1 with an inscribed circle diameter of 4.763 mm and a height of 10 mm, and one graphene capsule 2 in Example 2 is filled in each core cell 1. After filling, a layer of film is covered thereon, and then the first layer of honeycomb core is stacked.

[0139] The first layer of honeycomb core is an aramid paper honeycomb with a honeycomb size of 180×180 mm, an inscribed circle of a core cell 1 with a diameter of 3.17 mm and a height of 20 mm; the first layer of honeycomb core is divided into 5 regions of equal area from left to right, which are sequentially arranged as regions 1 to 5; each core cell 1 in the first region is filled with 4 graphene capsules 2 in Example 1; each core cell 1 in the second region is filled with 2 graphene capsules 2 in Example 1 and 3 graphene capsules 2 in Example 3; each core cell 1 in the third region is filled with 2 graphene capsules 2 in Example 1 and 2 graphene capsules 2 in Example 3; each core cell 1 in the fourth region is filled with 2 graphene capsules 2 in Example 1 and 1 graphene capsule 2 in Example 3; each core cell 1 in the fifth region is filled with 1 graphene capsule 2 in Example 1 and 1 graphene capsule 2 in Example 3;

[0140] S3. After the graphene capsule 2 is filled, the surface of the first layer of honeycomb core is covered with a film, and then covered with a cured quartz fiber board, and the whole is placed in an autoclave for curing.

[0141] The above description is only an optional embodiment of the present application, and does not limit the patent scope of the present application. All equivalent structural transformations made by using the contents of the present application specification and drawings under the inventive concept of the present application, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A graphene capsule, characterized in that: The graphene capsule comprises a capsule shell and a filler, wherein the capsule shell is made of a wave-transmitting material, and the filler is a graphene powder material.

2. The graphene capsule according to claim 1, characterized in that: The wave-transmitting material comprises at least one of a glass fiber composite material, a ceramic-based composite material and an organic wave-transmitting material.

3. The graphene capsule according to claim 1, characterized in that: The graphene powder material includes at least one of pure graphene powder and composite powder, and the composite powder includes graphene powder and magnetic particles.

4. The graphene capsule according to claim 1, characterized in that: The length of the capsule shell is 0.5 to 20 mm.

5. The graphene capsule according to claim 1, characterized in that: The thickness of the capsule shell is 0.01-0.1 mm.

6. A method for preparing a graphene capsule according to any one of claims 1 to 5, characterized in that: Includes steps: According to the wave absorbing performance requirements of the graphene capsule, the capsule shell is designed using electromagnetic wave material performance simulation software to determine the material and size parameters of the capsule shell; Prepare a capsule shell according to the determined material and size parameters; The graphene powder material is filled into the capsule shell to obtain a graphene capsule.

7. A honeycomb core absorbing material, comprising at least one layer of honeycomb core, characterized in that: The honeycomb core is filled with the graphene capsules according to any one of claims 1 to 5.

8. The honeycomb core absorbing material according to claim 7, characterized in that: The core cell height of the honeycomb core is greater than or equal to the length of the graphene capsule.

9. The honeycomb core absorbing material according to claim 7, characterized in that: It also includes skins, films and composite panels; One side of the honeycomb core is connected to the skin through the adhesive film, and the other side of the honeycomb core is connected to the composite board through the adhesive film.

10. A method for preparing the honeycomb core absorbing material according to claim 9, characterized in that: Includes steps: Cutting the skin to a desired size, and bonding the honeycomb core to the skin using the adhesive film; Filling the graphene capsules in the honeycomb core cells; After the graphene capsules are filled, the surface of the honeycomb core is covered with a glue film, and then covered with a composite board, and the whole is put into an autoclave for curing to obtain a honeycomb core wave absorbing material.

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