WO2018196516A1 - Élément structural absorbant les ondes et procédé de fabrication s'y rapportant - Google Patents

Élément structural absorbant les ondes et procédé de fabrication s'y rapportant Download PDF

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Publication number
WO2018196516A1
WO2018196516A1 PCT/CN2018/079812 CN2018079812W WO2018196516A1 WO 2018196516 A1 WO2018196516 A1 WO 2018196516A1 CN 2018079812 W CN2018079812 W CN 2018079812W WO 2018196516 A1 WO2018196516 A1 WO 2018196516A1
Authority
WO
WIPO (PCT)
Prior art keywords
prepreg
absorbing structure
film
layer
manufacturing
Prior art date
Application number
PCT/CN2018/079812
Other languages
English (en)
Chinese (zh)
Inventor
刘若鹏
赵治亚
王晨玥
Original Assignee
深圳光启高等理工研究院
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 深圳光启高等理工研究院 filed Critical 深圳光启高等理工研究院
Publication of WO2018196516A1 publication Critical patent/WO2018196516A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
    • B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C33/00—Moulds or cores; Details thereof or accessories therefor
    • B29C33/56—Coatings, e.g. enameled or galvanised; Releasing, lubricating or separating agents
    • B29C33/58—Applying the releasing agents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C33/00—Moulds or cores; Details thereof or accessories therefor
    • B29C33/56—Coatings, e.g. enameled or galvanised; Releasing, lubricating or separating agents
    • B29C33/68—Release sheets
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/40—Shaping or impregnating by compression not applied
    • B29C70/42—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles
    • B29C70/44—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding
    • B29C70/443—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding and impregnating by vacuum or injection
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
    • B29K2995/0037—Other properties
    • B29K2995/0091—Damping, energy absorption

Definitions

  • the present invention relates to the field of metamaterials, and more particularly to a absorbing structure and a method of making the same.
  • Harmful electromagnetic radiation can cause a certain degree of damage to the human body through thermal or non-thermal effects. Unnecessary electromagnetic radiation can also cause interference to airport flights and hospital medical equipment. Therefore, the absorbing structure capable of resisting or weakening the electromagnetic wave radiation is urgently needed to be developed and expanded.
  • the requirements for absorbing structural members are often not only absorbing characteristics, for example, in order to meet the lightweight design of the aircraft, the absorbing structural members on the aircraft should also have as small a weight as possible. Reduce the flight burden of the aircraft.
  • an object of the present invention is to provide a absorbing structure member with a lighter weight and a manufacturing method thereof.
  • a method of fabricating a absorbing structure comprises: forming a combined layer on a surface of a mold, the combined layer comprising at least one layer of honeycomb core; forming a carbon fiber layer on the combined layer; Demolding, the absorbing structure is obtained.
  • the step of forming a combined layer on the surface of the mold comprises: laying a layer on the surface of the mold to form a multilayer material for forming the combined layer; and first curing, curing the multilayer material to The combined layer.
  • the operating pressure is 0.1 to 0.3 MPa
  • the operating temperature is 100 to 220 degrees Celsius
  • the length is 2 to 9 hours.
  • the paving step comprises: laminating a first prepreg on the surface of the mold; laying a first adhesive film on the first prepreg; and laying a honeycomb on the first adhesive film a core; a second film is laid on the honeycomb core; and a second prepreg is laid on the second film.
  • At least one of the plurality of pavings included in the paving step is subjected to a vacuuming process after the paving.
  • the first prepreg is one of an epoxy quartz prepreg, a double horse quartz prepreg, and a cyanate quartz prepreg
  • the second prepreg is an epoxy quartz prepreg.
  • the first adhesive film is one of an epoxy film, a double horse film, and a cyanate film
  • the second film is an epoxy film, a double horse film, and a cyanate ester.
  • the step of forming a carbon fiber layer on the combined layer comprises: applying a third adhesive film on the combined layer; laying a carbon fiber prepreg on the third adhesive film; and second curing And curing the carbon fiber prepreg into the carbon fiber layer.
  • vacuuming treatment is also performed.
  • the third adhesive film is one of an epoxy film, a double horse film, and a cyanate film.
  • the carbon fiber prepreg is one of an epoxy carbon fiber prepreg, a double horse carbon fiber prepreg, and a cyanate carbon fiber prepreg.
  • the operating pressure is 0.1 to 0.3 MPa
  • the operating temperature is 100 to 220 degrees Celsius
  • the length is 2 to 9 hours.
  • the manufacturing method further comprises: applying a release agent to the surface of the mold; and after drying the release agent, on the release agent A release cloth is laid, and the combined layer is formed on the release cloth.
  • the release agent in the step of applying the release agent to the surface of the mold, 2 to 3 layers of the release agent are applied, and the coating directions of the adjacent layer release agents are crossed.
  • the manufacturing method further comprises: sanding the surface of the combined layer.
  • an absorbing structure is provided which is produced in accordance with the above-described method of fabricating a absorbing structure.
  • the absorbing structure is completed on the surface of the mold, and substantially comprises a combined layer and a carbon fiber layer, wherein the combined layer comprises at least one honeycomb core for providing a certain structural strength and
  • the formation of carbon fiber layer on the combined layer can further provide strong structural strength, while the carbon fiber is lighter than the traditional high-strength material, so that the obtained absorbing structural member can meet the high structural strength while maintaining Light quality, applied to neighborhoods that require lightweight design, such as aircraft neighborhoods, can result in greater productivity for the overall product.
  • FIG. 1 is a block diagram showing a method of fabricating a wave absorbing structure member according to a first embodiment of the present invention
  • FIG. 2 is a block diagram showing the process of step S110 in this embodiment
  • FIG. 3 is a block diagram showing the process of step S120 in this embodiment
  • Fig. 4 is a block diagram showing a method of fabricating a wave absorbing structure member according to a second embodiment of the present invention.
  • FIG. 1 is a block diagram showing a method of fabricating an absorbing structure according to a first embodiment of the present invention.
  • the method for fabricating the absorbing structure of the present embodiment includes steps S110 and S130.
  • step S110 a combined layer is formed on the surface of the mold, wherein the combined layer includes at least one layer of honeycomb cores.
  • step S110 may further include a paving step and a first curing step, wherein in the paving step, a multi-layer material for forming a combined layer is laminated on the surface of the mold, which includes steps S111 to S115.
  • Step S116 is the first curing step.
  • a first prepreg is laid on the surface of the mold, wherein the first prepreg is one of an epoxy quartz prepreg, a double horse quartz prepreg, and a cyanate quartz prepreg.
  • step S112 a first adhesive film is laid on the first prepreg, wherein the first adhesive film is one of an epoxy adhesive film, a double horse adhesive film, and a cyanate adhesive film.
  • step S113 a honeycomb core is laid on the first film for providing certain structural strength and absorbing properties to the absorbing structure.
  • step S114 a second adhesive film is laid on the honeycomb core, wherein the second adhesive film is one of an epoxy adhesive film, a double horse adhesive film, and a cyanate adhesive film.
  • step S115 a second prepreg is laid on the second film, wherein the second prepreg is an epoxy quartz prepreg, a double horse quartz prepreg, and a cyanate quartz prepreg.
  • the second prepreg is an epoxy quartz prepreg, a double horse quartz prepreg, and a cyanate quartz prepreg.
  • the vacuuming process is performed at least once after the tiling.
  • vacuuming may be performed after the paving of step S111, step S112, and step S115 is completed, or vacuuming may be performed after the paving of other steps is completed, but at least one pumping is performed. Vacuum treatment.
  • the raw materials for making the absorbing structural members are usually stored in a low temperature environment.
  • the prepreg, film, carbon fiber prepreg and other materials are taken out, and then thawed in a clean room, and kept in a sealed state. Handle as much as possible to avoid bumping the material.
  • the temperature of the clean room can be controlled at 18 ° C ⁇ 24 ° C, when the material temperature reaches the clean room temperature, and can be used without condensation after the outer film of the sealed bag is dried.
  • the thawing time is: at 20 ° C ⁇ 5 ° C, the thawing time is not less than 8 hours (the defrosting time of the prepreg that has been cut is not less than 2 hours).
  • the digital model of the product can be unfolded using the design software surface, and then the raw material of the absorbing structural member is cut into a corresponding shape.
  • step S116 a first curing step is performed, that is, the above multilayer material is cured into the combined layer.
  • the first curing step may be performed by a vacuum bag hot pressing method, and after the vacuum bag is prepared, it is placed in an autoclave to be solidified.
  • the curing operation pressure is 0.1 to 0.3 MPa
  • the operating temperature is 100 to 220 degrees Celsius
  • the duration is 2 to 9 hours. So far, step S110 is completed.
  • step S120 a carbon fiber layer is formed on the combined layer.
  • Fig. 3 shows a block diagram of the process of step S120 in the present embodiment. Specifically, step S120 may further include steps S121 to S123.
  • step S121 a third adhesive film is laid on the combined layer formed in the above step S110, wherein the third adhesive film is one of an epoxy adhesive film, a bismale film, and a cyanate adhesive film.
  • step S122 a carbon fiber prepreg is laid on the third film, wherein the carbon fiber prepreg is one of an epoxy carbon fiber prepreg, a double horse carbon fiber prepreg, and a cyanate carbon fiber prepreg. kind.
  • vacuuming is also performed.
  • step S123 a second curing is performed, that is, the carbon fiber prepreg is cured into a carbon fiber layer.
  • the second curing step may be performed by a vacuum bag hot pressing method, and after the vacuum bag is prepared, it is placed in an autoclave to be solidified.
  • the curing operation pressure is 0.1 to 0.3 MPa
  • the operating temperature is 100 to 220 degrees Celsius
  • the duration is 2 to 9 hours. So far, step S120 is completed.
  • step S130 demolding is performed, that is, the product is removed from the mold to obtain the absorbing structure.
  • the absorbing structure is completed on the surface of the mold, and generally comprises a combined layer and a carbon fiber layer, wherein the combined layer comprises at least one layer of honeycomb core for providing a certain structural strength and suction.
  • the formation of a carbon fiber layer on the combined layer can further provide strong structural strength, while the carbon fiber is lighter in weight than the conventional high-strength material, so that the obtained absorbing structure can meet the high structural strength while maintaining light weight.
  • the quality applied to neighborhoods that require lightweight design, such as aircraft neighborhoods, can result in greater productivity for the overall product.
  • FIG. 4 is a block diagram showing a method of fabricating a absorbing structure according to a second embodiment of the present invention.
  • the method for fabricating the absorbing structure of the present embodiment includes steps S210 and S260.
  • step S210 a mold release agent is applied to the surface of the mold.
  • the temperature of the surface of the mold is preferably not lower than 15 degrees Celsius, and the surface of the mold is ensured to be clean and dry before applying the release agent.
  • the release agent can be taken up with a dust-free cloth, and the surface of the mold is brushed, preferably 2 to 3 layers of the release agent are applied, each layer of the release agent is uniformly applied, and the release agent of the adjacent layer is applied. Cross the brush direction to ensure even brushing. If there is excessive application of the release agent, it should be wiped off from the mold with a clean cloth.
  • the last layer of release agent is applied and dried in the air for more than 40 minutes.
  • the site where the release agent is applied is preferably well ventilated and can be recorded after painting.
  • step S220 can be performed.
  • step S102 a release cloth is laid on the release agent.
  • the release cloth is often a plurality of pieces, and the area of each release cloth is not less than 10 square centimeters.
  • the stitching gap is not more than 1 mm, and the overlapping form is avoided as much as possible.
  • step S230 is performed to form a combined layer on the surface of the mold, wherein the combined layer comprises at least one layer of honeycomb cores.
  • Step S230 of this embodiment may be substantially the same as step S110 of the first embodiment, and is not described in detail herein.
  • the embodiment further includes step S240 of grinding the surface of the combined layer.
  • This step may be disposed between the step S230 of forming the combined layer and the step S250 of forming the carbon fiber layer, for example, by sanding with 180 to 240 mesh sandpaper to complete the surface of the first cured combined layer, so that the carbon fiber layer on the combined layer is formed later.
  • the combination with the combined layer is more compact, and the resulting absorbing structure is more integral.
  • step S250 and step S260 are performed.
  • step S250 a carbon fiber layer is formed on the combined layer; in step S260, demolding is performed, that is, the product is removed from the mold to obtain the absorbing structure.
  • Step S250 and step S260 of this embodiment may be substantially the same as steps S120 and S130 of the first embodiment, and will not be described in detail herein. Due to the presence of the release agent and the release cloth of the present embodiment, step S260 can be made easier, and the resulting absorbing structure is more complete in shape and closer to the precise design size.
  • the present invention also provides an absorbing structure which can be produced according to the method of fabricating the absorbing structure of any of the above embodiments.
  • the absorbing structure is completed on the surface of the mold, and substantially comprises a combined layer and a carbon fiber layer, wherein the combined layer comprises at least one honeycomb core for providing a certain structural strength and
  • the absorbing properties, the formation of carbon fiber layer on the combined layer can further provide strong structural strength, while the carbon fiber is lighter than the traditional high-strength material, so that the obtained absorbing structural member can meet the high structural strength while maintaining Light quality, applied to neighborhoods that require lightweight design, such as aircraft neighborhoods, can result in greater productivity for the overall product.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Moulding By Coating Moulds (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)

Abstract

L'invention concerne un élément structural absorbant les ondes et un procédé de fabrication s'y rapportant, le procédé de fabrication comprenant les étapes consistant : à former une couche combinée sur une surface d'un moule, la couche combinée comprenant au moins une couche de sandwich en nid d'abeilles ; à former une couche de fibres de carbone sur la couche combinée ; et à démouler cette dernière en vue d'obtenir l'élément structural absorbant les ondes. La fabrication de l'élément structural absorbant les ondes est achevée sur la surface du moule, et l'élément structural absorbant les ondes comprend grossièrement une couche combinée et une couche de fibres de carbone, la couche combinée comprenant au moins une couche de sandwich en nid d'abeilles destinée à fournir une certaine résistance structurale et une propriété d'absorption des ondes, et la couche de fibres de carbone formée sur la couche combinée pouvant en outre fournir une force structurale plus forte ; et en même temps, les fibres de carbone sont plus légères en termes de poids mort que les matériaux à résistance élevée classiques, ce qui permet à l'élément structural absorbant les ondes ainsi obtenu de satisfaire à des exigences de résistance structurale élevée tout en maintenant une masse plus légère, et lorsqu'il est appliqué à des champs qui nécessitent des conceptions légères, telles que le domaine des véhicules aériens, le produit global peut atteindre une efficacité de travail plus élevée.
PCT/CN2018/079812 2017-04-28 2018-03-21 Élément structural absorbant les ondes et procédé de fabrication s'y rapportant WO2018196516A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201710294755.0A CN108790209A (zh) 2017-04-28 2017-04-28 吸波结构件及其制作方法
CN201710294755.0 2017-04-28

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Publication Number Publication Date
WO2018196516A1 true WO2018196516A1 (fr) 2018-11-01

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WO (1) WO2018196516A1 (fr)

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Publication number Priority date Publication date Assignee Title
CN112743874A (zh) * 2020-12-11 2021-05-04 哈尔滨飞机工业集团有限责任公司 一种复合材料蜂窝夹层件胶膜的铺放方法
CN112848600A (zh) * 2021-01-04 2021-05-28 北京大学 超表面嵌入式承载吸波层合板及制备方法

Citations (3)

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Publication number Priority date Publication date Assignee Title
WO2003100364A2 (fr) * 2002-05-23 2003-12-04 Bell Helicopter Textron Inc. Procede et appareil de reduction des signatures infrarouge et radar d'un vehicule
CN203077713U (zh) * 2013-01-28 2013-07-24 苏州芳磊蜂窝复合材料有限公司 一种多层蜂窝夹芯复合材料
CN105291524A (zh) * 2014-05-26 2016-02-03 深圳光启创新技术有限公司 一种芳纶蜂窝夹芯板及其加工方法

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JP5861448B2 (ja) * 2011-12-26 2016-02-16 三菱電機株式会社 サンドイッチパネルの製造方法
ES1093805Y (es) * 2013-10-17 2014-06-18 Perrodo Patrick Alain Cuerpo constructivo modular de alta resistencia
CN106033837A (zh) * 2015-03-20 2016-10-19 深圳光启高等理工研究院 曲面基体超材料及其制造方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003100364A2 (fr) * 2002-05-23 2003-12-04 Bell Helicopter Textron Inc. Procede et appareil de reduction des signatures infrarouge et radar d'un vehicule
CN203077713U (zh) * 2013-01-28 2013-07-24 苏州芳磊蜂窝复合材料有限公司 一种多层蜂窝夹芯复合材料
CN105291524A (zh) * 2014-05-26 2016-02-03 深圳光启创新技术有限公司 一种芳纶蜂窝夹芯板及其加工方法

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