CN106342374B - A kind of multilayer absorption coating - Google Patents
A kind of multilayer absorption coatingInfo
- Publication number
- CN106342374B CN106342374B CN200810075570.1A CN200810075570A CN106342374B CN 106342374 B CN106342374 B CN 106342374B CN 200810075570 A CN200810075570 A CN 200810075570A CN 106342374 B CN106342374 B CN 106342374B
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Abstract
The invention provides a kind of multilayer Radar Absorbing Coating and preparation method thereof, microwave absorbing coating comprises the dielectric loss composite coating layer and the magnetic loss composite coating layer that are superimposed; Dielectric loss coating mainly comprises four acicular type zinc oxide crystal whisker, conductive black; Magnetic loss composite coating mainly comprises tri-iron tetroxide and nanometer iron powder; With spraying or spread coating construct on aluminium matter plate material, from bottom to surface layer spraying, order is: magnetosphere-dielectric layer-magnetosphere-dielectric layer ..., coating obtains microwave absorbing coating after normal temperature cure, and total coating thickness is 1.5 ± 0.1mm, the every layer thickness of mean allocation. Radar wave absorbing invisible coating of the present invention reaches-4～-6dB at the reflectivity of 4～8GHz wave band; Reflectivity at 8～18GHz wave band reaches-5～-8dB. Coat side density is 1.6 ± 0.2kg/m2Left and right, more than adhesive force reaches 13.5MPa, impact strength reaches 50kg.cm, and has good temperature tolerance and environmental stability.
Description
Technical field
The present invention relates to a kind of wave-absorbing and camouflage material (RAM), specifically, relate generally to a kind of multilayer radarAntiradar coatings and preparation method thereof.
Background technology
The development of stealth material and application are considered to the important breakthrough of military high-tech sector, modern stealthy skillArt mainly contains the stealthy design of construction profile and design and the application of stealth material. Advanced stealth material is hiddenEngineering application in body target plays a part very important, and it not only can be used to suppress minute surface ripple, also can press downRow ripple processed, creep and involve edge and penetrate echo. The Radar Absorbing Property of material is stealth material and stealth technologyImportant and key index; Radar-wave absorbing performance refer to material by with the work that incides its surperficial radar waveWith, the ability of decay target-echo intensity. Its general principle is conduction that radar wave is inducted in absorbing materialElectric current, magnetic hystersis loss or dielectric loss, make energy that the electromagnetic energy of radar wave is converted into other formation (as machineTool energy, electric energy and heat energy etc.) and consume, the object of RCS reduced to reach decay radar wave. Inhale rippleMaterial is generally composited by matrix material (as resin matrix) and lossy medium (inhaling ripple medium), the formerPlay cementation, the latter brings into play suction wave energy. And different lossy mediums has different radar wave absorption machinesReason, and demonstrate different wave-absorbing effects. Absorbing material, in application, is divided into coating-type and structural type two is largeFamily macromolecule composite. Coating-type material is taking the Polymer Solution such as resin type and rubber-type or emulsion as baseMaterial, wherein makes wave absorbing agent by certain proportioning.
In known technology, the research emphasis of absorbing material is nearly all concentrated on and finds and study new suction ripple mediumOn. At present, start application and mainly contained magnetic loss material, dielectric with the radar wave absorbing medium of studyingConsumable material two great causes, secondly also have resistor-type material, conduction high polymer, chirality high polymer etc. to inhale ripple materialMaterial. Taking ferrite, hydroxyl iron powder, iron fiber etc. as the magnetic loss material of representative be wherein study the most extensively,Application radar wave absorbing agent the earliest. Because material internal magnetic dipole consumes thunder with illuminating-radar wave motionDanone, therefore it has higher magnetic conductivity and moderate resistivity, makes electromagnetic wave be easy to enter material internalAnd obtain effective attenuation, therefore there is good wave-absorbing effect. But than great, difficult dispersion, oxidizable and residenceIn temperature low (occur magnetic domain reversion), heat-resisting quantity poor (higher than the oxidation rapidly of 500 degree), peel strengthThe defect such as low, channel is narrow, coating surface is coarse has almost limited its large-scale application.
Dielectricity absorbing material is another kind of important radar wave absorbing medium in known technology, although most ofDielectric material has advantages of lighter than ferrite, but its wave-absorbing effect, especially low-frequency range effect is not so good asMagnetic material, and require certain thickness just to show suitable absorbing property.
Conduction high polymer absorbing material in known technology, is difficult to separate although can solve many inorganic absorbentsThe problems such as adhesive force certainly, pliability, proportion, processability, the transparency, but it inhales ripple frequency range and effect beginsEventually unsatisfactory, seem also not reach requirement.
Making wave absorbing agent by nano material also has many reports, and has caused the great attention of various countries, but it inhales rippleMechanism is still not clear. Also deposit problem both ways from the situation of practical application: the one, powdery nanometer materialMaterial dispersing technology not yet solves, and the 2nd, stability and wave-absorbing effect are accepted not yet.
Though the chirality macromolecular material attracting great attention equally has development potentiality, synthesis technique and suctionReceiving bandwidth problem not yet solves so far.
From the angle of design of material, the material of single component to reach comprise absorbing property, mechanical property,It is very difficult that environmental performance, workability and other combination property require in the harshness aspect interior national defence.With the compound thinking of many components be perhaps the simple and effective method that meets functional requirement and structural behaviour. ItsOn tangible some advanced persons' of the U.S. stealthy weapon, this design and selection thinking are comprised, more advanced functionAlso among studying with structural composite material. Utilize conduction and the piezoelectric property of four needle-like ZnO whiskers, andIn conjunction with its unique space four acicular textures, the U.S. reports at its patent US 5310598 (1994), when it withAfter other radar wave absorbing medium is compound, obtain having at 1～20GHz wave band the suction ripple of certain absorbent propertiesMaterial. But more than its material thickness reaches 3.5mm.
The absorption of ZnOw to VHF, UHF, microwave and radar wave introduced in European patent EP-374795Performance, does not relate to the absorption to millimere-wave band yet.
Japan Patent JP04-91167 (1992) and JP03-143936 (1991) have reported four acicular type zinc oxide crystal whiskerAnd the electromagnetic shielding of polymer matrix composites and microwave heating function.
The national defence patent of invention (200510000942.0 and 200410029043.9) of our application in early stage is utilizedFour acicular type zinc oxide crystal whisker and carbon black etc. are compound, have prepared millimere-wave band and 8～12GHz wave band has better suctionProduce effects can invisible coating.
Summary of the invention
For RAM, the design of coating material and the research of absorbent are two large keys of absorbing material, thin,Gently, wide, be the general requirement to absorbing material by force. For this reason, the present invention proposes a kind of based on Multi-layer designBroadband Radar Absorbing Materials and preparation method thereof.
Alternately construction acquisition is many to the object of the present invention is to provide one to utilize dielectric loss layer and magnetic depletion layerThe method of layer absorbing material, wherein dielectric loss layer mainly utilizes the 26S Proteasome Structure and Function of four acicular type zinc oxide crystal whiskerParticularity, add appropriate conductive carbon black as resistance adjustment agent; Magnetic depletion layer mainly utilizes four oxidationsThe magnetic loss mechanism of three-iron and nanometer iron powder, has obtained a kind of surface density little and have wideband ripple absorbent propertiesWith good mechanics and absorbing material that can normal temperature cure.
Object of the present invention is achieved through the following technical solutions: according to the present invention, above-mentioned absorbing material comprises2～6 layers of different composite coating of (even level) content solidify and obtain, Qi Zhongfu after spraying or brush applicationClose coating and contain the compositions such as macromolecule resin binding agent, radar wave absorbing agent and diluent. Radar wave absorbing agentFor composite parts, and at least comprise two formula systems, one is dielectric loss layer, mainly comprises four pinsShape ZnOw, conductive black; It two is magnetic depletion layer, comprises tri-iron tetroxide, nickel oxide, oxygenChange the mixture of cobalt. The formula (by weight) that coating is each layer is: dielectric layer: polyurethane resin 15～30%,Cyclohexanone solvent 15～40%, four acicular type zinc oxide crystal whisker 35～60%, conductive black 5～15%; Magnetosphere:Polyurethane resin 5～10%, cyclohexanone solvent 10～15%, tri-iron tetroxide powder 50～70%, nanometer iron powder15～30%. Add appropriate diluent according to construction requirement. After the preliminary mixing of above-mentioned each composition, use mixerLow rate mixing 0.5～3 hour, removes by filter after a small amount of sediment with 60 order nylon cloths, executes with spraying or spread coatingWork is to aluminium matter plate material, and the spraying order of each layer is (from bottom to the every layer thickness of surface layer mean allocation):Magnetosphere-dielectric layer-magnetosphere-dielectric layer, coating obtains microwave absorbing coating, coating after normal temperature cureGross thickness is 1.5 ± 0.1mm.
The present invention, in the situation that total coating thickness keeps certain, replaces by dielectric loss layer and magnetic depletion layerConstruction, has obtained wideband Radar Stealth Materials, and its principle is can form material between dielectric layer and magnetosphereSharp interface in performance, can effectively reduce electromagnetic wave and once concentrate reflection and enter as much as possible materialMaterial is inner, and respectively by dielectric loss mechanism and tri-iron tetroxide powder and the nanometer of four acicular type zinc oxide crystal whiskerThe magnetic loss mechanism of iron powder realizes electromagnetic wave energy decay, reaches the effect of wave-absorbing and camouflage.
Four acicular type zinc oxide crystal whisker as dielectricity absorbent Main Ingredients and Appearance is high-temperature firing product, has betterTemperature tolerance and environmental stability. Each spicule length 10～200 μ m of this whisker, best 40～120 μ m; BrilliantPalpus root diameter (RD) 0.1～10 μ m, best 0.3～5 μ m. In composite, the use of ZnOwAmount is 35～60%. For the resistance of regulation and control ZnOw, add conductive black, its consumption is5～15%, so that composite reaches optimum impedance coupling, obtain best wave-absorbing effect. At magnetic depletion layer,Tri-iron tetroxide is micron-sized powder material, and particle diameter is 5～80 μ m, best 10～30 μ m, consumption 50～70%;Add nanometer iron powder, be the interfacial polarization effect in order to increase nano material, and utilize the high magnetic permeability of iron powderCharacteristic is widened absorption frequency range, nanometer iron powder particle diameter 5～200nm, best 10～50nm.
It should be noted that, the consumption of diluent does not strictly count formula, can according to mix and construction needs,In two kinds of coating compositions, add appropriate diluent respectively. The mixing of each component adopts mechanical type low rate mixing,Also can stir by hand. After mixing, under normal temperature nature, spray or brush in substrate or table of equipmentFace, coating layer thickness is 1.4～1.6mm.
Effect of the present invention is: by sandwich construction, significantly improved radar wave assimilation effect, and widenedFrequency range. Radar wave absorbing invisible coating of the present invention, in the situation that thickness is 1.5 ± 0.1mm, at 4～8GHzThe reflectivity of wave band reaches-4～-6dB; Reflectivity at 8～18GHz wave band reaches-5～-8dB, coat sideDensity is 1.6 ± 0.2kg/m2, more than adhesive force reaches 13.5MPa, impact strength reaches 50kg.cm, and toolThere are good temperature tolerance and environmental stability.
Brief description of the drawings
Fig. 1 is the scanning electron micrograph of the present invention's four acicular type zinc oxide crystal whisker used.
Fig. 2 is the projection electron microphoto that the present invention's Nanoscale Iron used divides.
Fig. 3 is the flat reflective rate curve of embodiment 1 gained coating.
Fig. 4 is the flat reflective rate curve of embodiment 2 gained coatings.
Fig. 5 is the flat reflective rate curve of embodiment 3 gained coatings.
Fig. 6 is the flat reflective rate curve of comparative example gained coating.
Fig. 7 is each multilayer antiradar coatings Example formulations and the performance table of comparisons.
Detailed description of the invention
The following examples can illustrate in greater detail the present invention, but do not limit in any form the present invention.
Embodiment 1
By polyurethane lacquer (carbimide prepolymer and curing agent total amount) 25%, four acicular type zinc oxide crystal whisker60%, conductive black 5%, cyclohexanone 10% is after the preliminary mixing of each composition, little with mixer low rate mixing 2Time, obtain dielectric layer antiradar coatings composition; Polyurethane lacquer (carbimide prepolymer and curing agent total amount)7%, tri-iron tetroxide 50%, nanometer iron powder 30%, cyclohexanone 13%, after the preliminary mixing of each composition, with stirringMix machine low rate mixing 2 hours, obtain magnetosphere antiradar coatings composition. Two kinds of coating compositions use respectively 60After order filter-cloth filtering, add appropriate diluent according to construction requirement, be sprayed at successively the smooth aluminium that 2.5mm is thickOn plate, dielectric layer and magnetic layer thickness are all controlled at 0.75 ± 0.05mm, after solidifying, obtain 1.5 ± 0.1mmThick coating. As shown in Figure 3, other performance is listed Fig. 7 table in to the radar reflection rate curve of the present embodiment coatingIn.
Embodiment 2
By polyurethane lacquer (carbimide prepolymer and curing agent total amount) 30%, four acicular type zinc oxide crystal whisker40%, conductive black 15%, cyclohexanone 15%, after the preliminary mixing of each composition, with mixer low rate mixing 1Hour, obtain dielectric layer antiradar coatings composition; (carbimide prepolymer and curing agent are total for polyurethane lacquerAmount) 5%, tri-iron tetroxide 70%, nanometer iron powder 15%, cyclohexanone 10%, after the preliminary mixing of each composition,With mixer low rate mixing 3 hours, obtain magnetosphere antiradar coatings composition. Two kinds of coating compositions respectivelyWith after 60 order filter-cloth filterings, add appropriate diluent according to construction requirement, according to dielectric layer-magnetosphere-JieElectricity layer-magnetosphere sequence alternate is sprayed on the smooth aluminium sheet that 2.5mm is thick, and every layer thickness is controlled at0.375 ± 0.005mm obtains the coating that 1.5 ± 0.1mm is thick after solidifying. The radar of the present embodiment coating is anti-Penetrate rate curve as shown in Figure 4, other performance is listed in Fig. 7 table.
Embodiment 3
By polyurethane lacquer (carbimide prepolymer and curing agent total amount) 15%, four acicular type zinc oxide crystal whisker35%, conductive black 10%, cyclohexanone 40%, after the preliminary mixing of each composition, with mixer low rate mixing 0.5Hour, obtain dielectric layer antiradar coatings composition; (carbimide prepolymer and curing agent are total for polyurethane lacquerAmount) 10%, tri-iron tetroxide 57%, nanometer iron powder 18%, cyclohexanone 15%, after the preliminary mixing of each composition,With mixer low rate mixing 1 hour, obtain magnetosphere antiradar coatings composition. Two kinds of coating compositions respectivelyWith after 60 order filter-cloth filterings, add appropriate diluent according to construction requirement, according to dielectric layer-magnetosphere-JieElectricity layer-magnetosphere-dielectric layer-magnetosphere sequence alternate is sprayed on the smooth aluminium sheet that 2.5mm is thick, every layerTHICKNESS CONTROL, at 0.25 ± 0.05mm, obtains the coating that 1.5 ± 0.1mm is thick after solidifying. The present embodiment coatingRadar reflection rate curve as shown in Figure 5, other performance is listed in Fig. 7 table.
Comparative example
Comparative example of the present invention is identical with the formula of embodiment 2, does not just take construction in layer, butAfter directly adopting each component to mix, obtain by the construction of individual layer antiradar coatings, that is:
By polyurethane lacquer (carbimide prepolymer and curing agent total amount) 17.5%, four acicular type zinc oxide crystal whisker20%, conductive black 7.5%, cyclohexanone 12.5%, tri-iron tetroxide 35%, nanometer iron powder 7.5%, respectively becomesDivide after preliminary mixing, use mixer low rate mixing 2 hours, obtain mixing antiradar coatings composition, use 60 ordersAfter filter-cloth filtering, add appropriate diluent according to construction requirement, be sprayed on the smooth aluminium sheet that 2.5mm is thick, thickDegree is controlled at 1.5 ± 0.1mm. The radar reflection rate curve of this comparative example coating as shown in Figure 6, other performanceList in Fig. 7 table.
Can think, above-described embodiment is only described in the mode of enumerating, and can also have many according to thisWorking of an invention mode, for example, do appropriate change by component ratio wherein. Therefore the technology people to this areaMember, various changes and change that the present invention is made are apparent, can not depart from structure of the present inventionThink and the protection domain of additional claim.
Claims (4)
1. a multilayer absorption coating, described microwave absorbing coating by the dielectric loss composite coating layer being superimposed andMagnetic loss composite coating layer composition; Described dielectric loss composite coating mainly comprises four-needle-like zinc oxide crystalline substancePalpus, conductive black; Described magnetic loss composite coating mainly comprises tri-iron tetroxide and nanometer iron powder; HeavyAmount percentage meter, dielectric loss composite coating: polyurethane resin 15～30%, cyclohexanone solvent 15～40%,Four acicular type zinc oxide crystal whisker 35～60%, conductive black 5～15%; Magnetic loss composite coating: polyurethaneResin 5～10%, cyclohexanone solvent 10～15%, tri-iron tetroxide powder 50～70%, nanometer iron powder 15～
30％。
2. multilayer absorption coating claimed in claim 1, is characterized by four acicular type zinc oxide crystal whisker needle-like usedBody length is 40～120 μ m.
3. the multilayer absorption coating described in claim 1 or 2, is characterized by described tri-iron tetroxide for micronLevel powder body material, particle diameter is 10～30 μ m; Nanometer iron powder particle diameter 10～50nm.
4. multilayer absorption coating claimed in claim 1, the spraying order that it is characterized by each layer is: magnetosphere-dielectric layer-magnetosphere-dielectric layer ..., total coating thickness is 1.5 ± 0.1mm, flat from bottom to surface layerAll distribute every layer thickness.
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| CN200810075570.1A CN106342374B (en) | 2008-05-23 | 2008-05-23 | A kind of multilayer absorption coating |
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| CN200810075570.1A CN106342374B (en) | 2008-05-23 | 2008-05-23 | A kind of multilayer absorption coating |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106332534A (en) * | 2015-07-10 | 2017-01-11 | 深圳光启尖端技术有限责任公司 | Wave absorber structure |
| CN108617160A (en) * | 2018-06-22 | 2018-10-02 | 四川大学 | A kind of absorbing material and preparation method thereof |
| CN109049913A (en) * | 2018-06-29 | 2018-12-21 | 安徽尼古拉电子科技有限公司 | A kind of high temperature resistant radar absorbing and preparation method thereof based on the double-deck Meta Materials |
| CN109526192A (en) * | 2018-11-07 | 2019-03-26 | 中国航发北京航空材料研究院 | Wave suction composite material |
| CN111969330A (en) * | 2020-07-31 | 2020-11-20 | 航天科工武汉磁电有限责任公司 | Radar wave-absorbing material with unit structure pattern and preparation method thereof |
| CN112094575A (en) * | 2020-09-24 | 2020-12-18 | 航天特种材料及工艺技术研究所 | Preparation method of magnetic wave-absorbing material resistant to marine environment |
| CN112350075A (en) * | 2020-10-19 | 2021-02-09 | 内蒙古大学 | Multilayer composite material with strong microwave absorption in GHz interval and preparation method thereof |
| CN116478598A (en) * | 2023-05-17 | 2023-07-25 | 新疆戍边方阵装备科技有限公司 | High-temperature-resistant radar wave absorbing coating and spraying process thereof |
-
2008
- 2008-05-23 CN CN200810075570.1A patent/CN106342374B/en active Active
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106332534A (en) * | 2015-07-10 | 2017-01-11 | 深圳光启尖端技术有限责任公司 | Wave absorber structure |
| CN106332534B (en) * | 2015-07-10 | 2020-03-10 | 深圳光启尖端技术有限责任公司 | Wave absorber structure |
| CN108617160A (en) * | 2018-06-22 | 2018-10-02 | 四川大学 | A kind of absorbing material and preparation method thereof |
| CN109049913A (en) * | 2018-06-29 | 2018-12-21 | 安徽尼古拉电子科技有限公司 | A kind of high temperature resistant radar absorbing and preparation method thereof based on the double-deck Meta Materials |
| CN109526192A (en) * | 2018-11-07 | 2019-03-26 | 中国航发北京航空材料研究院 | Wave suction composite material |
| CN111969330A (en) * | 2020-07-31 | 2020-11-20 | 航天科工武汉磁电有限责任公司 | Radar wave-absorbing material with unit structure pattern and preparation method thereof |
| CN112094575A (en) * | 2020-09-24 | 2020-12-18 | 航天特种材料及工艺技术研究所 | Preparation method of magnetic wave-absorbing material resistant to marine environment |
| CN112350075A (en) * | 2020-10-19 | 2021-02-09 | 内蒙古大学 | Multilayer composite material with strong microwave absorption in GHz interval and preparation method thereof |
| CN112350075B (en) * | 2020-10-19 | 2023-01-31 | 内蒙古大学 | Multilayer composite material with strong microwave absorption in GHz interval and preparation method thereof |
| CN116478598A (en) * | 2023-05-17 | 2023-07-25 | 新疆戍边方阵装备科技有限公司 | High-temperature-resistant radar wave absorbing coating and spraying process thereof |
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