CN110746671A - Wave-absorbing material for microwave anechoic chamber, wave-absorbing pyramid and preparation method of wave-absorbing pyramid - Google Patents
Wave-absorbing material for microwave anechoic chamber, wave-absorbing pyramid and preparation method of wave-absorbing pyramid Download PDFInfo
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- CN110746671A CN110746671A CN201910848412.3A CN201910848412A CN110746671A CN 110746671 A CN110746671 A CN 110746671A CN 201910848412 A CN201910848412 A CN 201910848412A CN 110746671 A CN110746671 A CN 110746671A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
- C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
- C08L23/04—Homopolymers or copolymers of ethene
- C08L23/06—Polyethene
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
- H05K9/0083—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising electro-conductive non-fibrous particles embedded in an electrically insulating supporting structure, e.g. powder, flakes, whiskers
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2227—Oxides; Hydroxides of metals of aluminium
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/32—Phosphorus-containing compounds
- C08K2003/321—Phosphates
- C08K2003/322—Ammonium phosphate
- C08K2003/323—Ammonium polyphosphate
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/02—Flame or fire retardant/resistant
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
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Abstract
The invention discloses a wave-absorbing material for a microwave anechoic chamber, which comprises the following components in parts by weight: 10-15 parts of conductive carbon black, 40-50 parts of PE resin and 5-10 parts of a dispersing agent, wherein the rest components comprise a flame retardant and a fiber material, the wave-absorbing pyramid for the microwave anechoic chamber is provided with a display structure, the display structure is formed by repeatedly arranging a plurality of pyramids in the horizontal direction, protrusions are arranged on the outer wall of each pyramid, the electromagnetic wave absorbent, the resin and the flame retardant are uniformly mixed by the preparation method of the wave-absorbing pyramid, an injection molding or blow molding process is used for integral forming to obtain a wave-absorbing pyramid shell, and then the pyramid shell is filled with a corresponding wave-absorbing material to prepare the pyramid. The beneficial technical effects of the invention are as follows: meanwhile, the polyurethane polymer has excellent wave-absorbing performance, flame retardant performance and power resistance, and the electromagnetic wave absorption performance between 2GHz and 40GHz is 5dB higher than that of the conventional polyurethane pyramid.
Description
Technical Field
The invention relates to a wave-absorbing material for a microwave anechoic chamber, a wave-absorbing pyramid and a preparation method of the wave-absorbing pyramid, and belongs to the technical field of electromagnetic shielding.
Background
The microwave darkroom is an important guarantee facility for scientific research and production of a modern weapon equipment system, and provides electromagnetic environment conditions meeting requirements for scientific research and production of weapon equipment. The wave-absorbing material is a functional composite material, is the core of a microwave anechoic chamber and can effectively absorb electromagnetic wave energy irradiated on the wave-absorbing material, so that the reflected or scattered energy of the electric wave is obviously attenuated. With the development of modern weaponry and civil communication industries, microwave darkrooms are widely applied, and the large-scale development of wave-absorbing materials is driven. At present, the common microwave darkroom pyramid type wave-absorbing material comprises a polyurethane foam pyramid, a non-woven fabric pyramid, an EPS pyramid, an EPP pyramid and the like according to different base materials. Among them, polyurethane foam pyramid is the most widely used wave-absorbing pyramid in domestic use because of its advantages such as low cost and high performance. The wave-absorbing material in the prior art has a great promotion space in the aspect of absorbing electromagnetic waves.
Disclosure of Invention
The invention aims to provide a wave-absorbing material for a microwave anechoic chamber, a wave-absorbing pyramid and a preparation method thereof, and overcomes the defects in the prior art.
The invention is realized by adopting the following technical scheme:
the wave-absorbing material for the anechoic chamber is characterized by comprising the following components in parts by mass: 10-15 parts of conductive carbon black, 40-50 parts of PE resin and 5-10 parts of a dispersing agent, and the balance of components comprise a flame retardant and a fiber material.
Further, the wave-absorbing material comprises the following components in parts by weight: 13 parts of conductive carbon black, 45 parts of PE resin and 9 parts of a dispersing agent.
Further, the flame retardant comprises: 60-65 parts of deionized water, 12-15 parts of PVA solution, 12-14 parts of aluminum hydroxide, 1-4 parts of kaolin, 2-2.5 parts of pentaerythritol, 31-2 parts of ammonium polyphosphate App-1, 0.1-0.2 part of wetting agent and 0.1-0.2 part of defoaming agent.
Further, the fiber agent comprises: 50-55 parts of epoxy resin matrix, 1-5 parts of curing agent, 15-25 parts of graphene fiber and 8-12 parts of microwave absorbent.
Further, the inside of the pyramid is filled with conductive polyurethane particles.
The graphene fiber is a graphene fiber bundle, the fiber bundle is vertically dispersed in epoxy resin to form an array with equal spacing, and the microwave absorbent is uniformly dispersed in the epoxy resin, wherein the particle size of the polyurethane is less than or equal to 5mm, and the surface resistance is less than or equal to 300 omega.
The wave-absorbing pyramid for the microwave anechoic chamber is characterized by comprising a display structure, wherein the display structure is formed by repeatedly arranging a plurality of pyramids in the horizontal direction, a horizontal base is arranged below the display structure of each pyramid, and protrusions are arranged on the outer wall of each pyramid.
Further, the protrusions are triangular.
A preparation method of a wave-absorbing pyramid for a microwave anechoic chamber is characterized in that the wave-absorbing pyramid is divided into a pyramid shell and a wave-absorbing material filled inside the pyramid shell, an electromagnetic wave absorbent, resin and a fire retardant are uniformly mixed and then are integrally formed by using an injection molding or blow molding process to obtain the wave-absorbing pyramid shell, and then the pyramid shell is filled with the corresponding wave-absorbing material to prepare the pyramid.
The beneficial technical effects of the invention are as follows: the pyramid shell consumes most energy of electromagnetic waves in a surface absorption mode, the polyurethane wave-absorbing material consumes the energy of the electromagnetic waves in a bulk absorption mode, and meanwhile, the polyurethane wave-absorbing material has excellent wave-absorbing performance, flame retardant performance and power resistance performance, the impedance matching performance of the pyramid is improved, various advantages are effectively combined together, and the electromagnetic wave absorption performance of the pyramid is 5dB higher than that of the conventional polyurethane pyramid in the range of 2 GHz-40 GHz.
Drawings
Fig. 1 is a schematic view of a prior art pyramid structure.
Fig. 2 is a schematic view of the pyramid structure with protrusions of the present invention.
Fig. 3 is a schematic view of a pyramid structure filled with conductive polyurethane particles.
Detailed Description
The invention will be better understood by the following description of embodiments thereof, but the applicant's specific embodiments are not intended to limit the invention to the particular embodiments shown, and any changes in the definition of parts or features and/or in the overall structure, not essential changes, are intended to define the scope of the invention.
As shown in fig. 1 to 3, the common wave-absorbing pyramid processing technology cannot achieve the complex structure of this embodiment, and therefore in this embodiment, the wave-absorbing pyramid uses an integrated molding method to divide the wave-absorbing pyramid into two parts, namely, a pyramid shell and a wave-absorbing material filled inside, and after the electromagnetic wave absorbent, the resin, the fire retardant and the like are uniformly mixed, the wave-absorbing pyramid shell is obtained by using an injection molding or blow molding technology to be integrated (fig. 2), and then the pyramid shell is filled with the corresponding wave-absorbing material to form a novel wave-absorbing pyramid (fig. 3), so that the pyramid has more excellent absorption performance.
The wave-absorbing material for the microwave anechoic chamber comprises the following components in parts by weight: 10-15 parts of conductive carbon black, 40-50 parts of PE resin and 5-10 parts of a dispersing agent, and the balance of components comprise a flame retardant and a fiber material. In this example, the conductive carbon black, PE resin, flame retardant, and dispersant are preferably mixed in a ratio of 13: 45: 33: 9, processing the mixture into a pyramid shell shown in figure 2 by using an injection molding process, and then filling conductive polyurethane particles into the pyramid shell, wherein the conductive polyurethane is an irregular block material, the particle size is less than or equal to 5mm, and the surface resistance is less than or equal to 300 omega. Tests show that the electromagnetic wave absorption performance of the pyramid at 2 GHz-40 GHz is 5dB higher than that of the conventional polyurethane pyramid due to the fact that the impedance matching performance of the pyramid is improved.
The wave-absorbing material is further optimized in the embodiment, and the formula of the wave-absorbing material in parts by mass is as follows: 13 parts of conductive carbon black, 45 parts of PE resin and 9 parts of a dispersing agent, wherein the flame retardant comprises: 60-65 parts of deionized water, 12-15 parts of PVA solution, 12-14 parts of aluminum hydroxide, 1-4 parts of kaolin, 2-2.5 parts of pentaerythritol, 0.1-0.2 part of ammonium polyphosphate App-31, 0.1-0.2 part of wetting agent, 0.1-0.2 part of defoaming agent, and the fiber agent comprises: 50-55 parts of epoxy resin matrix, 1-5 parts of curing agent, 15-25 parts of graphene fiber and 8-12 parts of microwave absorbent, wherein conductive polyurethane particles are filled in the pyramid. The graphene fiber is a graphene fiber bundle, the fiber bundle is vertically dispersed in epoxy resin to form an array with equal spacing, and the microwave absorbent is uniformly dispersed in the epoxy resin, wherein the particle size of the polyurethane is less than or equal to 5mm, and the surface resistance is less than or equal to 300 omega.
The wave-absorbing pyramid structure on the basis of the above embodiment is as follows: the wave-absorbing pyramid is provided with a display structure, the display structure is formed by repeatedly arranging a plurality of pyramids in the horizontal direction, a horizontal base is arranged below the display structure of the pyramids, and protrusions are arranged on the outer walls of the pyramids, preferably the protrusions are triangular. The preparation method of the wave-absorbing pyramid for the microwave anechoic chamber comprises the following steps: the wave-absorbing pyramid is divided into two parts, namely an pyramid shell and a pyramid shell, wherein wave-absorbing materials are filled in the pyramid shell, electromagnetic wave absorbent, resin and flame retardant are uniformly mixed and then are integrally formed by using an injection molding or blow molding process, so that the wave-absorbing pyramid shell is obtained, and then the pyramid shell is filled with corresponding wave-absorbing materials to be manufactured into the pyramid.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore intended that all such changes and modifications as fall within the true spirit and scope of the invention be considered as within the following claims.
Claims (8)
1. The wave-absorbing material for the anechoic chamber is characterized by comprising the following components in parts by mass: 10-15 parts of conductive carbon black, 40-50 parts of PE resin and 5-10 parts of a dispersing agent, and the balance of components comprise a flame retardant and a fiber material.
2. The wave-absorbing material for the anechoic chamber according to claim 1, which is prepared from the following components in parts by weight: 13 parts of conductive carbon black, 45 parts of PE resin and 9 parts of a dispersing agent.
3. The wave-absorbing material for the anechoic chamber as claimed in claim 1, wherein the flame retardant comprises: 60-65 parts of deionized water, 12-15 parts of PVA solution, 12-14 parts of aluminum hydroxide, 1-4 parts of kaolin, 2-2.5 parts of pentaerythritol, 31-2 parts of ammonium polyphosphate App-1, 0.1-0.2 part of wetting agent and 0.1-0.2 part of defoaming agent.
4. The wave-absorbing material for the anechoic chamber according to claim 1, wherein the fiber agent comprises: 50-55 parts of epoxy resin matrix, 1-5 parts of curing agent, 15-25 parts of graphene fiber and 8-12 parts of microwave absorbent.
5. The wave-absorbing material for the microwave anechoic chamber as claimed in claim 4, wherein the inside of the pyramid is filled with conductive polyurethane particles.
6. The wave-absorbing pyramid for the microwave anechoic chamber is characterized by comprising a display structure, wherein the display structure is formed by repeatedly arranging a plurality of pyramids in the horizontal direction, a horizontal base is arranged below the display structure of each pyramid, and protrusions are arranged on the outer wall of each pyramid.
7. The wave-absorbing pyramid for the anechoic chamber as claimed in claim 6, wherein the protrusions are triangular.
8. A preparation method of a wave-absorbing pyramid for a microwave anechoic chamber is characterized in that the wave-absorbing pyramid is divided into a pyramid shell and a wave-absorbing material filled inside the pyramid shell, an electromagnetic wave absorbent, resin and a fire retardant are uniformly mixed and then are integrally formed by using an injection molding or blow molding process to obtain the wave-absorbing pyramid shell, and then the pyramid shell is filled with the corresponding wave-absorbing material to prepare the pyramid.
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| CN201910848412.3A CN110746671A (en) | 2019-09-09 | 2019-09-09 | Wave-absorbing material for microwave anechoic chamber, wave-absorbing pyramid and preparation method of wave-absorbing pyramid |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115490945A (en) * | 2022-09-15 | 2022-12-20 | 南京科频电子科技有限公司 | Wave-absorbing material for microwave anechoic chamber and preparation process of wave-absorbing pyramid |
| CN117089142A (en) * | 2023-09-19 | 2023-11-21 | 亿策科技有限公司 | Wave absorber with internal through holes, preparation method and extrusion foaming processing line |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102675738A (en) * | 2012-05-15 | 2012-09-19 | 金发科技股份有限公司 | Heat-resistant conductive polypropylene composite material and preparation method thereof |
| CN103483792A (en) * | 2012-06-14 | 2014-01-01 | 潘智军 | Wave absorption and radiation protection plastic and preparation method thereof |
| CN104445934A (en) * | 2014-11-11 | 2015-03-25 | 中国人民解放军国防科学技术大学 | High-temperature-resistant wedge-shaped microwave absorbing material and preparation method thereof |
| CN104558396A (en) * | 2014-12-30 | 2015-04-29 | 东莞市维美德电子材料有限公司 | Nano wave-absorbing and shielding material and preparation method thereof |
| CN106496949A (en) * | 2016-11-10 | 2017-03-15 | 无锡市明盛强力风机有限公司 | A kind of composite fiber microwave absorbing material |
| CN107082938A (en) * | 2017-06-14 | 2017-08-22 | 南京波平电子科技有限公司 | Thermoplastic resin foam pyramid high-performance wave-absorbing material and its design, manufacture method |
| CN108192315A (en) * | 2018-02-09 | 2018-06-22 | 重庆邮电大学 | A kind of vehicle instrument instrument housing electromagnetic shielding composite material and preparation method thereof |
| CN109152319A (en) * | 2018-09-18 | 2019-01-04 | 南京波平电子科技有限公司 | The suction wave shell and preparation method thereof of the complex contour structure opposite sex |
| CN109228000A (en) * | 2018-09-07 | 2019-01-18 | 南京波平电子科技有限公司 | Dedicated absorbing material of vehicle radar antenna and preparation method thereof |
| CN109796623A (en) * | 2019-01-28 | 2019-05-24 | 南京波平电子科技有限公司 | A kind of electromagnetic compatibility takes into account antenna measurement absorbing material and preparation method thereof |
| CN110144125A (en) * | 2019-06-13 | 2019-08-20 | 慧迈材料科技(广东)有限公司 | A kind of manufacturing method for inhaling wave TPO material |
-
2019
- 2019-09-09 CN CN201910848412.3A patent/CN110746671A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102675738A (en) * | 2012-05-15 | 2012-09-19 | 金发科技股份有限公司 | Heat-resistant conductive polypropylene composite material and preparation method thereof |
| CN103483792A (en) * | 2012-06-14 | 2014-01-01 | 潘智军 | Wave absorption and radiation protection plastic and preparation method thereof |
| CN104445934A (en) * | 2014-11-11 | 2015-03-25 | 中国人民解放军国防科学技术大学 | High-temperature-resistant wedge-shaped microwave absorbing material and preparation method thereof |
| CN104558396A (en) * | 2014-12-30 | 2015-04-29 | 东莞市维美德电子材料有限公司 | Nano wave-absorbing and shielding material and preparation method thereof |
| CN106496949A (en) * | 2016-11-10 | 2017-03-15 | 无锡市明盛强力风机有限公司 | A kind of composite fiber microwave absorbing material |
| CN107082938A (en) * | 2017-06-14 | 2017-08-22 | 南京波平电子科技有限公司 | Thermoplastic resin foam pyramid high-performance wave-absorbing material and its design, manufacture method |
| CN108192315A (en) * | 2018-02-09 | 2018-06-22 | 重庆邮电大学 | A kind of vehicle instrument instrument housing electromagnetic shielding composite material and preparation method thereof |
| CN109228000A (en) * | 2018-09-07 | 2019-01-18 | 南京波平电子科技有限公司 | Dedicated absorbing material of vehicle radar antenna and preparation method thereof |
| CN109152319A (en) * | 2018-09-18 | 2019-01-04 | 南京波平电子科技有限公司 | The suction wave shell and preparation method thereof of the complex contour structure opposite sex |
| CN109796623A (en) * | 2019-01-28 | 2019-05-24 | 南京波平电子科技有限公司 | A kind of electromagnetic compatibility takes into account antenna measurement absorbing material and preparation method thereof |
| CN110144125A (en) * | 2019-06-13 | 2019-08-20 | 慧迈材料科技(广东)有限公司 | A kind of manufacturing method for inhaling wave TPO material |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115490945A (en) * | 2022-09-15 | 2022-12-20 | 南京科频电子科技有限公司 | Wave-absorbing material for microwave anechoic chamber and preparation process of wave-absorbing pyramid |
| CN115490945B (en) * | 2022-09-15 | 2023-11-17 | 南京科频电子科技有限公司 | Preparation technology of wave-absorbing material and wave-absorbing pyramid for microwave darkroom |
| CN117089142A (en) * | 2023-09-19 | 2023-11-21 | 亿策科技有限公司 | Wave absorber with internal through holes, preparation method and extrusion foaming processing line |
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