阅读说明：本技术 一种磁性宽频带电磁吸波超材料 (Magnetic broadband electromagnetic wave-absorbing metamaterial ) 是由 庄海燕 陈翔 叶志民 赵涵 陈小平 于 2020-04-21 设计创作，主要内容包括：本发明公开了一种磁性宽频带电磁吸波超材料,该电磁吸波超材料从下至上包括三层：反射层、介质层和阵列层,所述阵列层是由多个呈矩形阵列间隔排布在介质层上方的磁性结构单元组成的；该电磁吸波超材料的制备方法为：在介质层的一侧粘贴反射层；在介质层远离反射层的一侧打磨出与各磁性结构单元的位置相对应的贴敷区,所述贴敷区的形状与磁性结构单元的底面形状相匹配,贴敷区的粗糙度小大于40μm；在各贴敷区位置粘贴或喷涂磁性结构单元进而形成阵列层,即制得电磁吸波超材料。该电磁吸波超材料在2~18GHz范围内具有优异的宽频带吸波性能,可应用到电子设备、飞机、船舰、军用车辆及设施外表面。(The invention discloses a magnetic broadband electromagnetic wave-absorbing metamaterial, which comprises three layers from bottom to top: the array layer is composed of a plurality of magnetic structure units which are arranged above the dielectric layer in a rectangular array at intervals; the preparation method of the electromagnetic wave-absorbing metamaterial comprises the following steps: sticking a reflecting layer on one side of the dielectric layer; grinding an application area corresponding to the position of each magnetic structure unit on one side of the dielectric layer away from the reflecting layer, wherein the shape of the application area is matched with the shape of the bottom surface of each magnetic structure unit, and the roughness of the application area is less than or equal to 40 mu m; and adhering or spraying the magnetic structure units at the positions of the pasting areas to form an array layer, thereby obtaining the electromagnetic wave-absorbing metamaterial. The electromagnetic wave-absorbing metamaterial has excellent broadband wave-absorbing performance in the range of 2-18 GHz, and can be applied to the outer surfaces of electronic equipment, airplanes, ships, military vehicles and facilities.)

1. The utility model provides a magnetism broadband electromagnetism wave-absorbing metamaterial which characterized in that, this electromagnetism wave-absorbing metamaterial includes the three-layer from supreme down: the array layer is composed of a plurality of magnetic structure units which are arranged above the dielectric layer in a rectangular array at intervals; the preparation method of the electromagnetic wave-absorbing metamaterial comprises the following steps:

(1) sticking a reflecting layer on one side of the dielectric layer;

(2) grinding a pasting area corresponding to the position of each magnetic structure unit on one side of the dielectric layer away from the reflecting layer, wherein the shape of the pasting area is matched with the shape of the bottom surface of each magnetic structure unit, and the roughness of the pasting area is less than 40 microns;

(3) and adhering or spraying the magnetic structure units at the positions of the pasting areas to form an array layer, thereby obtaining the electromagnetic wave-absorbing metamaterial.

2. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 1, wherein the magnetic structure unit is formed by mixing a soft magnetic material and an adhesive, wherein the soft magnetic material is hydroxyl iron, FeCo alloy or ferrite, and the adhesive is a high molecular polymer.

3. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 1, wherein in the step (3), the method for fixing each magnetic structure unit to the application area is spraying, die pressing or 3D printing.

4. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 3, wherein the specific method for fixing each magnetic structure unit to the application area by adopting a spraying process comprises the following steps: fixing the hole sieve plate on one side of the dielectric layer with the application area, spraying the prepared mixture for preparing the magnetic structure unit onto the hole sieve plate by adopting spraying equipment, and removing the hole sieve plate after the mixture is solidified into a film to obtain an array layer; the positions of all holes on the hole sieve plate are consistent with the positions of the application areas, and the diameters and the heights of all the holes and all the magnetic structure units are consistent.

5. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 3, wherein the specific method for fixing each magnetic structure unit to the application area by mold compression molding or 3D printing comprises the following steps: firstly, each magnetic structure unit is manufactured through mould compression molding or 3D printing, and the manufactured magnetic structure units are adhered to the corresponding adhering areas.

6. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 1, wherein the magnetic structural units are cylindrical, hexagonal, ellipsoidal, prismatic, cubic or rectangular.

7. The magnetic broadband electromagnetic wave absorbing metamaterial according to claim 1, wherein the dielectric layer is any one of an FR-4 board, a polyester film, a polycarbonate film or a polyimide film.

8. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 1, wherein the dielectric constant of the dielectric layer is 2-7.

9. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 1, wherein the reflecting layer is made of any one of steel, iron, copper, silver, aluminum or carbon fiber.

10. The magnetic broadband electromagnetic wave-absorbing metamaterial according to claim 1, wherein the row pitch and the column pitch in the array layer are respectively equal.

Technical Field

The invention relates to the field of special functional materials, in particular to a magnetic broadband electromagnetic wave-absorbing metamaterial.

Background

The metamaterial is a novel artificial material which is vigorously developed at home and abroad in recent years, can realize extraordinary physical characteristics which are not possessed by the nature through artificial design, and also provides an unprecedented new idea for the development of wave-absorbing materials. The electromagnetic wave-absorbing metamaterial is an artificial electromagnetic material which is composed of periodically arranged structural units and has a sub-wavelength scale and can absorb electromagnetic waves, and after a perfect wave-absorbing metamaterial is researched and prepared in 2008 N.I. Landy, the electromagnetic wave-absorbing metamaterial is widely researched and greatly developed.

Chinese patent publication No. CN103018926A discloses a tunable artificial electromagnetic metamaterial with respect to topology and graphene, in which a topology material and a graphene material are introduced into an electromagnetic wave-absorbing metamaterial, so that a resonant frequency corresponding to an absorption peak of the electromagnetic wave-absorbing metamaterial changes, and thus, a frequency band of an absorption spectrum of the electromagnetic wave-absorbing metamaterial has tunability. The wave-absorbing artificial electromagnetic metamaterial is of a multilayer structure, a metal layer, a dielectric layer and a metal layer are grown on a substrate material, a periodic resonance unit array is manufactured on a top metal layer, and finally a topological material layer or a graphene material layer is plated on the surface of the periodic resonance unit array. Chinese patent publication No. CN106785468A discloses a wave-absorbing-wave-transmitting integrated metamaterial, the metamaterial structural unit includes a first terrace with edges and a second terrace with edges, both the first terrace with edges and the second terrace with edges are formed by alternately stacking a plurality of first dielectric layers and a plurality of first metal layers in a direction perpendicular to a frequency selective surface unit; the frequency selection surface unit comprises a second dielectric layer and a second metal layer on the second dielectric layer, and the middle metal area of each edge of the second metal layer is etched to form a groove. However, in the above patents, the soft magnetic material is not used as the periodic unit of the metamaterial to achieve the wave absorbing effect in a wider frequency band, and the manufacturing technology is complicated.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a magnetic broadband electromagnetic wave-absorbing metamaterial which has excellent broadband wave-absorbing performance within the range of 2-18 GHz.

In order to achieve the purpose, the invention adopts the specific scheme that:

a magnetic broadband electromagnetic wave-absorbing metamaterial comprises three layers from bottom to top: the array layer is composed of a plurality of magnetic structure units which are arranged above the dielectric layer in a rectangular array at intervals; the preparation method of the electromagnetic wave-absorbing metamaterial comprises the following steps:

(1) sticking a reflecting layer on one side of the dielectric layer;

(2) grinding a pasting area corresponding to the position of each magnetic structure unit on one side of the dielectric layer away from the reflecting layer, wherein the shape of the pasting area is matched with the shape of the bottom surface of each magnetic structure unit, and the roughness of the pasting area is not more than 40 mu m;

(3) and adhering or spraying the magnetic structure units at the positions of the pasting areas to form an array layer, thereby obtaining the electromagnetic wave-absorbing metamaterial.

Furthermore, the magnetic structure unit is formed by mixing a soft magnetic material and an adhesive, wherein the soft magnetic material is hydroxyl iron, FeCo alloy or ferrite, and the adhesive is a high molecular polymer. In detail, the adhesive may be a two-component epoxy resin, a two-component polyurethane resin, or a two-component rubber.

Further, in the step (3), the method for fixing each magnetic structure unit to the application area is spraying process, die pressing or 3D printing.

Further, the specific method for fixing each magnetic structure unit to the application area by adopting the spraying process comprises the following steps: fixing the hole sieve plate on one side of the dielectric layer with the application area, spraying the prepared mixture for preparing the magnetic structure unit onto the hole sieve plate by adopting spraying equipment, and removing the hole sieve plate after the mixture is solidified into a film to obtain an array layer; the positions of all holes on the hole sieve plate are consistent with the positions of the application areas, and the diameters and the heights of all the holes and all the magnetic structure units are consistent.

Further, a specific method for fixing each magnetic structure unit to the application area by mold compression molding or 3D printing is as follows: firstly, each magnetic structure unit is manufactured through mould compression molding or 3D printing, and the manufactured magnetic structure units are adhered to the corresponding adhering areas.

Further, the shape of the magnetic structure unit is cylindrical, hexagonal, ellipsoid, prismoid, cube or cuboid.

Further, the dielectric layer is made of an FR-4 board, a polyester film, a polycarbonate film or a polyimide film.

Further, the dielectric constant of the dielectric layer is 2-7.

Further, the material of the reflecting layer is any one of steel, iron, copper, silver, aluminum or carbon fiber.

Furthermore, the row spacing and the column spacing in the array layer are respectively equal.

Has the advantages that:

1. in the invention, soft magnetic materials are used as main additives of the magnetic structure unit, and besides the traditional quarter thickness matching wave absorption mechanism, the design of the magnetic structure unit enables the magnetic resonance generated by the structure unit, the anti-parallel current effect between layers, the grating effect of the periodic structure and the like to achieve a wider wave absorption effect.

2. The soft magnetic material forming the magnetic structure unit adopts the soft magnetic material with the frequency dispersion characteristic in the microwave band, and the soft magnetic material is a double-complex dielectric material with the dielectric frequency dispersion characteristic and the magnetic frequency dispersion characteristic, so that the soft magnetic material serving as a periodic structure is more beneficial to widening the wave-absorbing frequency band than a pure dielectric material, and the magnetic property of the soft magnetic material has great effect on widening the wave-absorbing frequency band.

3. The dielectric constant of the dielectric layer is 2-7 because the metamaterial is a typical three-layer absorber structure, the dielectric constant of the dielectric layer is not too high, otherwise, an anti-parallel current response cannot be formed between the surface layer and the bottom reflecting layer, and a wave absorbing mechanism is influenced.

4. The prepared electromagnetic wave-absorbing metamaterial has excellent broadband wave-absorbing performance in the range of 2-18 GHz, can be applied to electronic equipment, effectively reduces electromagnetic radiation of the equipment, and realizes electromagnetic compatibility among the equipment; the method can also be used for the outer surfaces of airplanes, ships, military vehicles and facilities, can effectively reduce the radar scattering cross section, has the radar stealth effect, and has better military significance and social benefit.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of the electromagnetic wave-absorbing metamaterial (a magnetic structural unit is a cylinder).

FIG. 2 is a graph of the electromagnetic parameters of FeCo alloy and adhesive in the present invention.

Figure 3 is a schematic illustration of the dielectric layer after polishing of the application region.

FIG. 4 is a schematic diagram of an electromagnetic wave-absorbing metamaterial prepared by the method.

The labels in the figure are: 1. a reflecting layer 2, a dielectric layer 3 and a magnetic structure unit.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to specific embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, belong to the scope of the present invention.

A magnetic broadband electromagnetic wave-absorbing metamaterial comprises three layers from bottom to top: the array substrate comprises a reflecting layer, a dielectric layer and an array layer; the dielectric constant of the dielectric layer is 2-7, and the dielectric layer is any one of an FR-4 board, a polyester film, a polycarbonate film or a polyimide film. The reflecting layer is made of any one of steel, iron, copper, silver, aluminum or carbon fiber. The array layer is composed of a plurality of magnetic structure units which are arranged above the dielectric layer in a rectangular array at intervals, and the distance between each row and each column in the array layer is respectively equal; the magnetic structure unit is formed by mixing a soft magnetic material and an adhesive, wherein the soft magnetic material is hydroxyl iron, FeCo alloy or ferrite, and the adhesive is a high molecular polymer, such as two-component epoxy resin, two-component polyurethane resin or two-component rubber. The magnetic structure unit is cylindrical, hexagonal, ellipsoid, prismatic table, cubic or cuboid.

The preparation method of the electromagnetic wave-absorbing metamaterial comprises the following steps:

(1) sticking a reflecting layer on one side of the dielectric layer;

(2) grinding a pasting area corresponding to the position of each magnetic structure unit on one side of the dielectric layer away from the reflecting layer, wherein the shape of the pasting area is matched with the shape of the bottom surface of each magnetic structure unit, and the roughness of the pasting area is less than 40 microns;

(3) and adhering or spraying the magnetic structure units at the positions of the pasting areas to form an array layer, thereby obtaining the electromagnetic wave-absorbing metamaterial.

In the step (3), the method for fixing each magnetic structure unit in the application area is spraying process, mould compression molding or 3D printing.

The specific method for fixing each magnetic structure unit in the application area by adopting the spraying process comprises the following steps: fixing the hole sieve plate on one side of the dielectric layer with the application area, spraying the prepared mixture for preparing the magnetic structure unit onto the hole sieve plate by adopting spraying equipment, and removing the hole sieve plate after the mixture is solidified into a film to obtain an array layer; the positions of all holes on the hole sieve plate are consistent with the positions of the application areas, and the diameters and the heights of all the holes and all the magnetic structure units are consistent.

The specific method for fixing each magnetic structure unit in the application area by adopting die compression molding or 3D printing comprises the following steps: firstly, each magnetic structure unit is manufactured through mould compression molding or 3D printing, and the manufactured magnetic structure units are adhered to the corresponding adhering areas.