RU2300832C2 - Anti-radar material - Google Patents

Abstract

FIELD: anti-radar materials.

SUBSTANCE: proposed material has polymeric binder and powdered filler produced from mixture of ferric carbonate, ferrite, and fullerene in definite proportion of ingredients. This anti-radar material can be applied directly to surface under protection and/or to flexible electricity conducting warm made of woven or nonwoven material used to produce flexible cover with anti-radar material on top that can reflect electromagnetic waves of power reduced by 10 - 30 dB compared with prior art.

EFFECT: reduced level and/or power of electromagnetic wave reflected from entity under protection.

1 cl, 1 dwg, 2 tbl

Description

Technical field

The invention relates to materials that reduce the magnitude and / or power of the reflected signal from the electromagnetic wave of the radar in a wide frequency range, and can be used as a protective device to reduce the radar visibility of objects of various sizes and configurations in the radar range of "visibility" of electromagnetic waves (EMW) .

State of the art

A known absorber of electromagnetic radiation (US patent 5,561,428, class H01Q 17/00), in which the filler is made in the form of randomly oriented threads forming a three-dimensional porous structure, while a conductive layer is applied to part of the threads.

Its disadvantages include the difficulty of manufacturing when applying a conductive layer to the filaments and forming a uniform three-dimensional filament structure from filaments.

Known synthetic dielectric material of broadband absorption and reflection (US patent 5,298,903, CL H01Q 17/00) containing a synthetic material with distributed in it ellipsoid Rayleigh reflectors with a maximum linear size smaller than the smallest wavelength in a given frequency range. Rayleigh particles are an insulator coated with a thin metal shell. The thickness of the material selected is greater than the maximum wavelength of the working strip in the synthetic material.

The disadvantages of this material include the complexity of its manufacture and application to the protected object.

The closest in technical essence and purpose to the claimed invention is the radar absorbing material described in the patent (RU 2107705 C1, CL C09D 5/32; C08K 3/10, publ. 03/27/98). It uses a synthetic adhesive "Elaton" as a polymer binder, and powdered ferrite or carbonyl iron in the ratio, wt.%: "Elaton" - 80-20; magnetic filler 20-80.

Disclosure of invention

The technical problem to which the invention is directed is the creation of an elastic anti-radar material that eliminates or significantly reduces the likelihood of detection and / or classification of objects when using stationary and mobile radars operating in the frequency range from 8 GHz to 13 GHz. In this case, the anti-radar material can be applied directly to the surface of the protected object and / or on a flexible electrically conductive base made of woven and / or non-woven material, from which a cover coated with anti-radar material is made.

The technical result achieved by the implementation of the invention is to reduce the level and / or power of the reflected electromagnetic wave from the object in the direction of the irradiating radar by 10-30 dB (depending on the required magnitude of reduction) with respect to the level and / or power of the locating electromagnetic wave of the radar when placed at any distance no closer than one hundred meters from the protected object.

The specified technical result is achieved in that in the anti-radar material containing a polymeric binder and a powdery filler, a mixture of carbonyl iron, ferrite and fullerene is used as filler in the following ratio of components, wt.%:

polymer binder 40-60 ferrite 9-6 carbonyl iron 42-28 fullerene 9-6

wherein fullerene is used in the form of a mixture of fullerenes C-60 and C-70 in the following ratio of components, wt.%:

fullerene S-60 70-99.9 fullerene S-70 30-0.1

and ferrite and carbonyl iron are used in the form of spherical particles with a diameter of 10-50 microns.

Adding fullerenes to the composition leads to the appearance of specific atomic-molecular structures in the material, in which, under the influence of an incident electromagnetic wave, electron density fluctuations occur, which significantly reduce the level and / or power of the electromagnetic wave reflected into the surrounding space.

The presence of randomly oriented and uniformly located in the volume of the polymer binder filler particles of various sizes leads to the formation of Rayleigh scattering structures of various sizes, which leads to the expansion of the working frequency range of the proposed material.

A diagram of the attenuation of the level and / or power of the reflected radar wave in the frequency range 8-13 GHz when using a polymer with a filler without fullerene and with fullerene is shown in the drawing.

The above characteristics are obtained for a material with a thickness of approximately 1.7 mm deposited on a metal base. The filler is made in the form of a mixture of carbonyl iron, ferrite and fullerenes (70% C-60, 30% C-70) in the following ratio of components, wt.%: 85; 5 and 10, respectively.

As a polymer binder, for example, latexes of grades SKS-50GPS (GOST 14053-78), BS-50 "A" (GOST 15080-77), BSK-70/2 (TU 38.103541-88), DL-950 can be used .

The material can also be applied to a flexible electrically conductive base. This results in flexible coatings that can be used to create radar covers. As a flexible electrically conductive base, non-woven materials shown in table 1 can be used.

To create an external decorative layer, enamels can be used, for example, grades АС-1151 (acrylic styrene, TU 6-10-1029-83), ХВ 16 (vinyl chloride TU 6-10-1301-83), ЭП-140 (epoxy GOST 24709 -81), HFA 133, 132,130 (US production MILC-83286, polyurethane semi-gloss, matte, glossy, article 31738/317155/317011). The above enamels are applied to the coating either directly or on the underlying soil.

Examples of carrying out the invention

Anti-radar material is prepared by mechanically mixing the components immediately before applying it to the surface to be coated. Depending on the required value of reducing the level and / or power of the reflected electromagnetic wave, appropriate ratios of the components of the filler are prepared.

After measurements made at the facility, three local areas with different, high levels and / or powers of the reflected electromagnetic wave were detected. The first - in the form of an angular reflector on the surface of the object, the second was an edge formed by the intersection of two planes, the third - in the form of a flat plate located normal to the axis of irradiation.

To attenuate reflection from the first section, it was required to apply anti-radar material with formulation No. 1 1.5 mm thick on it. This resulted in a 13 dB reduction in reflection. A 2 mm thick anti-radar material with formulation No. 2 was sprayed onto the second portion, resulting in a 19 dB decrease in reflection. To attenuate reflection from the third region, a layer of material 0.8 mm thick was applied to the plate with formulation No. 3, which led to a decrease in reflection by 11 dB. The composition of the formulations are presented in table 2.

Table 2. Recipe number 1 polymer binder - 40 ferrite - 9 carbonyl iron - 42 fullerene - 9 Recipe number 2 polymer binder - 46 ferrite - 7 carbonyl iron - 40 fullerene - 7 Recipe number 3 polymer binder - 50 ferrite - 7 carbonyl iron - 36 fullerene - 7

The anti-radar material works as follows. A part of the electromagnetic wave incident on the material from the microwave energy space is absorbed by converting the molecules of the filler material into the energy of thermal motion, and a part is randomly reflected into the space. All particles of the filler that are uniformly distributed in the polymer base by elementary point emitters with wide radiation patterns repeatedly participate in the rereflection. The re-reflection of the electromagnetic wave is not mirror but diffuse (by analogy from optics, the “dusty mirror” effect can be cited).

Industrial applicability

The use of the invention reduces the visibility of the protected object in the radar range of electromagnetic waves (EMW). The production and use of the inventive material does not impose strict requirements on the safety of personnel and technological equipment, because All materials used are non-toxic.

Claims (1)

An anti-radar material containing a polymer binder and a powdery filler, characterized in that a mixture of carbonyl iron, ferrite and fullerene is used as filler in the following ratio of components, wt.%: Polymer binder 40-60 Ferrite 9-6 Carbonyl iron 42-28 Fulleren 9-6 wherein fullerene is used in the form of a mixture of fullerenes C-60 and C-70 in the following ratio of components, wt.%: Fulleren S-60 70-99.9 Fulleren S-70 30-0.1 and ferrite and carbonyl iron are used in the form of spherical particles with a diameter of 10-50 microns.