CN118175828A

CN118175828A - Wave-absorbing material, preparation method and device

Info

Publication number: CN118175828A
Application number: CN202410611286.0A
Authority: CN
Inventors: 舒金表; 陈阿龙; 宣臣超; 张秀燕; 钱宏铭; 王雷; 张雪峰; 孔阳
Original assignee: Zhejiang Dahua Technology Co Ltd
Current assignee: Zhejiang Dahua Technology Co Ltd
Priority date: 2024-05-16
Filing date: 2024-05-16
Publication date: 2024-06-11

Abstract

The application discloses a wave-absorbing material, a preparation method and a device. The wave absorbing material comprises titanium silicon carbide which is of a laminated ordered cavity structure. The existence of the laminated ordered cavity structure can enable the titanium silicon carbide to have better wave absorption performance and heat dissipation performance.

Description

Wave-absorbing material, preparation method and device

Technical Field

The application relates to the technical field of electromagnetic compatibility, in particular to a wave-absorbing material, a preparation method and a device.

Background

Any minor disturbance may cause the device to malfunction in highly integrated electronic equipment due to the high sensitivity of the electronic components to electromagnetic fields. If an electronic device without any electromagnetic interference (EMI) shielding is exposed to an electromagnetic field generated by nearby devices, the electronic device will be prone to malfunction.

The problems of heat dissipation caused by the gradual miniaturization, compact structure and high power density of high-power density electronic devices, high-end electronic industrial devices and the like pose serious challenges for the working stability and reliability of the devices. However, the traditional wave absorbing material has the problems of phase interface and phonon simple harmonic vibration mismatch, so that phonons are scattered, and the interface thermal resistance between the filler and the matrix is high, thereby being unfavorable for improving the thermal conductivity.

The statements made above merely serve to provide background information related to the present disclosure and may not necessarily constitute prior art.

Disclosure of Invention

The application mainly solves the technical problem of providing a wave-absorbing material, a preparation method and a device, which can improve the heat radiation performance and the wave-absorbing performance of the wave-absorbing material.

In order to solve the technical problems, the application adopts a technical scheme that: a wave absorbing material is provided, which comprises titanium silicon carbide, wherein the titanium silicon carbide is of a laminated ordered cavity structure.

In order to solve the technical problems, the application adopts another technical scheme that: provided is a method for preparing a wave-absorbing material, comprising: providing a titanium silicon carbide raw material; etching the titanium silicon carbide raw material to obtain uniform laminated titanium silicon carbide; mixing the uniformly laminated titanium silicon carbide and a bulking agent to obtain a uniform mixture; and placing the uniform mixture in a reducing atmosphere, heating to 100 ℃ and preserving heat for 0.5h, and then heating to 150 ℃ and preserving heat for 1h to obtain the wave-absorbing material.

In order to solve the technical problems, the application adopts another technical scheme that: providing a device which is a wave absorbing device or a heat dissipating device, wherein the device comprises the wave absorbing material; or comprises the titanium silicon carbide modified material prepared by the method.

The titanium silicon carbide laminated material comprises a titanium silicon carbide laminated layer, wherein a plurality of holes (namely cavities) are formed between two adjacent layers in the titanium silicon carbide laminated layer, and the cavities in the laminated layer are orderly arranged, so that electromagnetic waves can be reflected and absorbed for a plurality of times in the ordered cavity structure of the titanium silicon carbide, when the electromagnetic waves are injected into the surface of the uniformly laminated expanded Ti ₃SiC₂, part of the electromagnetic waves can be reflected back by a conductive layer on the surface, so that the quantity of the electromagnetic waves entering the inside of an object is reduced, and a better shielding effect can be achieved, so that the wave absorbing material has stronger wave absorbing performance, and Ti ₃SiC₂ has the characteristics of metal, good heat conducting performance and electric conducting performance at normal temperature, relatively lower Vickers hardness and higher elastic modulus; the alloy has ductility at normal temperature, can be processed like metal, and has plasticity at high temperature; meanwhile, the ceramic material has the properties of ceramic material, high yield strength, high melting point, high thermal stability and good oxidation resistance, and can keep high strength at high temperature, so that the wave-absorbing material has better heat dissipation performance and wave-absorbing performance.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an ideal structure of a titanium silicon carbide modified material;

FIG. 2 is a schematic view of the microstructure of the titanium silicon carbide modified material of the present application;

FIG. 3 is a schematic view of the microstructure of a uniformly laminated titanium silicon carbide of the present application;

FIG. 4 is a schematic representation of the puffed titanium silicon carbide of the present application;

FIG. 5 is a comparative schematic illustration of the shielding properties of the titanium silicon carbide modified material of the present application and a conventional titanium silicon carbide material;

FIG. 6 is a schematic diagram showing a comparison of the thermal conductivity of the titanium silicon carbide modified material of the present application and a conventional titanium silicon carbide material;

FIG. 7 is a schematic view of an embodiment of a wave absorbing film according to the present application;

FIG. 8 is a schematic view of an embodiment of a shielding absorbing film according to the present application;

FIG. 9 is a schematic view of another embodiment of a shielding absorbing film according to the present application;

FIG. 10 is a schematic view of a shielding absorbing film according to another embodiment of the present application;

FIG. 11 is a schematic view of a shielding absorbing film according to another embodiment of the present application;

FIG. 12 is a schematic view of an embodiment of a wave-absorbing heat sink according to the present application;

FIG. 13 is a schematic view of another embodiment of a wave-absorbing heat sink according to the present application;

FIG. 14 is a schematic diagram showing the insertion loss curves of two embodiments of the wave-absorbing radiator of the present application;

FIG. 15 is an electron microscopic schematic of a titanium silicon carbide powder produced by the method of comparative example 1;

FIG. 16 is an electron microscope schematic of a titanium silicon carbide powder produced by the method of example 3.

Detailed Description

In order to make the objects, technical solutions and effects of the present application clearer and more specific, embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present application, and thus are merely examples, and are not intended to limit the scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion.

In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the term "plurality" means two or more (including two), and similarly, "plural sets" means two or more (including two), and "plural sheets" means two or more (including two), unless otherwise specifically defined.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is merely an association relationship describing an association object, and indicates that three relationships may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

Amounts, ratios, and other numerical values are presented herein in a range format. It is to be understood that such range format is used for convenience and brevity and should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited.

All the steps of the present application may be performed sequentially, randomly, or in parallel, preferably sequentially, unless otherwise specified. For example, the method comprises steps (a) and (b), meaning that the method may comprise steps (a) and (b) performed sequentially, may comprise steps (b) and (a) performed sequentially, and may be performed simultaneously. For example, the method may further comprise step (c), meaning that step (c) may be added to the method in any order, e.g., the method may comprise steps (a), (b) and (c), may also comprise steps (a), (c) and (b), may also comprise steps (c), (a) and (b), etc.

The application provides a wave-absorbing material, which comprises titanium silicon carbide Ti ₃SiC₂. As shown in fig. 1 and 2, the titanium silicon carbide in the wave-absorbing material has a laminated ordered cavity structure. Wherein titanium silicon carbide is subjected to a layering process (e.g., etching process) to form a laminated structure. And, a plurality of pore channels (i.e. cavities) are formed between two adjacent layers in the titanium silicon carbide lamination, as shown in fig. 2, the cavities in the lamination are arranged in a relatively orderly manner. Thus, as shown in fig. 1, electromagnetic waves can be reflected and absorbed for many times in the ordered cavity structure of titanium silicon carbide, so that when the electromagnetic waves are injected into the surface of the uniformly laminated expanded Ti ₃SiC₂, part of the electromagnetic waves are reflected back by the conductive layer on the surface, so that the quantity of the electromagnetic waves entering the inside of an object is reduced, and a better shielding effect can be achieved, so that the wave absorbing material has stronger wave absorbing performance, and the Ti ₃SiC₂ has the characteristics of metal, good heat conducting performance and electric conducting performance at normal temperature, relatively lower vickers hardness and higher elastic modulus; the alloy has ductility at normal temperature, can be processed like metal, and has plasticity at high temperature; meanwhile, the ceramic material has the properties of ceramic material, high yield strength, high melting point, high thermal stability and good oxidation resistance, and can keep high strength at high temperature, so that the wave-absorbing material has better heat dissipation performance and wave-absorbing performance. Alternatively, the titanium silicon carbide of the present application may be applied to the field of electromagnetic compatibility (EMC).

More preferably, the cavity in the titanium silicon carbide is elliptical, the long axis of the cavity is 200-400 nm, and the short axis of the elliptical is 130-210nm, so that the size of the cavity of the titanium silicon carbide is relatively large, and the titanium silicon carbide can better reflect and absorb electromagnetic waves. Of course, in other embodiments, the titanium silicon carbide cavity may have other shapes such as circular, conical, or cylindrical.

Optionally, the bending part in the laminated ordered hole structure of the titanium silicon carbide is covalently bonded, so that the titanium silicon carbide can form effective connection at the bending part, a good ordered hole form can be maintained, the interface thermal resistance at the joint part is relatively smaller, the heat transfer effect is enhanced, and a better heat dissipation effect can be maintained.

In addition, the cavity of the titanium silicon carbide can be filled with a wave absorbing substance and/or a heat dissipating substance so as to improve the wave absorbing performance and the heat dissipating performance of the titanium silicon carbide material.

The application provides a preparation method of a titanium silicon carbide modified material, which comprises the following steps:

Providing a titanium silicon carbide raw material; etching the titanium silicon carbide raw material to obtain uniform laminated titanium silicon carbide as shown in figure 3; mixing the uniformly laminated titanium silicon carbide and a bulking agent to obtain a uniform mixture; placing the uniform mixture in a reducing atmosphere, heating to 95-105 ℃ and preserving heat for 0.3-1h, then heating to 145-155 ℃ and preserving heat for 0.5-1.5h to obtain the titanium silicon carbide with the laminated ordered hole structure shown in figure 4, wherein the laminated ordered hole structure of the titanium silicon carbide can be shown in figure 2. According to the preparation method, the titanium silicon carbide can be gradually puffed to form a laminated ordered cavity structure by controlling the reaction time of the puffing reaction temperature of the uniformly laminated titanium silicon carbide and the temperature time maintained in the rising process, so that the cracking of the structure caused by the too high puffing speed of the titanium silicon carbide can be avoided, and the laminated ordered cavity network form of the titanium silicon carbide can be maintained, so that the titanium silicon carbide with better wave absorbing performance and heat conducting performance can be prepared by the preparation method. Specifically, the temperature is kept at 100 ℃ for 30min to gradually expand, so that the phenomenon that the whole network is affected due to the fact that the structure is broken due to the fact that the expansion speed is too high is avoided; reacting for 1h at 150 ℃ to expand the mixture to an optimal state and maintain the morphological structure of the mixture.

In one embodiment, the uniformly laminated titanium silicon carbide can be uniformly dispersed in a solvent to obtain a uniformly laminated titanium silicon carbide solution; then adding a proper amount of bulking agent, stirring for a period of time, and drying at a preset temperature to obtain a uniform mixture. In order to improve the dispersing effect of the uniformly laminated titanium silicon carbide, the uniformly laminated titanium silicon carbide colloid dispersion liquid (namely the uniformly laminated titanium silicon carbide solution) can be obtained by adding the uniformly laminated titanium silicon carbide into a proper amount of solvent, stirring for a period of time at a preset rotating speed, and then performing ultrasonic dispersion for a period of time. In addition, the predetermined temperature is less than the decomposition temperature of the bulking agent, for example sodium bicarbonate, and the predetermined temperature may be less than 50 ℃. In other embodiments, the bulking agent may be n-butylamine, etc., without limitation.

Alternatively, the ratio of the bulking agent to the uniformly layered titanium silicon carbide may be within a range, for example, within the range of "1:1.5-1:3", and the degree of bulking of the titanium silicon carbide may be adjusted by adjusting the ratio between the bulking agent and the uniformly layered titanium silicon carbide so that the titanium silicon carbide has different shielding properties. It is preferable that the mass ratio between the bulking agent and the uniformly layered titanium silicon carbide is 1:2, and as shown in FIG. 5, the titanium silicon carbide (i.e., uniformly layered bulked Ti ₃SiC₂ in FIG. 5) prepared in this ratio has excellent electromagnetic wave absorption performance at 30Mhz-18Ghz, and its shielding performance is improved by nearly 30dB, compared to the titanium silicon carbide (i.e., ordinary Ti ₃SiC₂ in FIG. 5) in the non-bulked state prepared without using the bulking agent.

In one specific example, 10g of the uniformly layered titanium silicon carbide powder may be added to 150ml of a 3:1 water and ethanol mixed solution, and uniformly stirred for 3 hours at 300 r/min. Then, uniformly laminating titanium silicon carbide colloid dispersion liquid is obtained through ultrasonic dispersion for 1 h; then, 5g of sodium bicarbonate was added and stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a uniform mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate.

Alternatively, the reducing atmosphere during the puffing reduction treatment may be a hydrogen atmosphere, a nitrogen atmosphere, or the like, without limitation.

In addition, in order to enhance the puffing effect, the temperature rising rate may be controlled within a certain range, for example, within a temperature rising rate range of more than 2 ℃/min and less than 10 ℃/min. More preferably, the rate of temperature increase is 5℃per minute.

Alternatively, the titanium silicon carbide feedstock may be self-made or commercially available.

The titanium silicon carbide raw material can be prepared by taking carbon powder, titanium powder and silicon powder as raw materials through high-temperature sintering. In one embodiment, titanium powder, carbon powder and silicon powder can be placed into vacuum according to the mass fraction ratio of 10:2:3 for high-temperature sintering at 1500 ℃ through vacuum pressureless sintering, and the titanium silicon carbide raw material is obtained.

Optionally, etching is performed on the titanium silicon carbide raw material by adopting etching modes such as hydrofluoric acid etching, molten salt etching, electrochemical etching, ionic liquid etching and the like, so that the titanium silicon carbide is layered, and the etched titanium silicon carbide is of a uniform laminated structure, namely, the laminated structure of the etched titanium silicon carbide is of uniform spacing by controlling etching conditions.

Taking the molten salt method as an example, the etching treatment of the titanium silicon carbide may include: mixing the titanium silicon carbide raw material and halogenated salt, and then placing the mixture in a salt bed of the halogenated salt; and heating the salt bed and the titanium silicon carbide raw material in the salt bed to 1150-1200 ℃ at a heating rate of 150-200 ℃/h in vacuum, preserving heat for 2-4h, cooling to 590-610 ℃, adding an etchant, reacting for 10min-1h, and cooling to room temperature to obtain the uniform laminated titanium silicon carbide. Therefore, silicon atoms in the Ti ₃SiC₂ compound can not be etched by controlling the rising rate of the reaction temperature and the reaction time, and only three substances of Ti, si and C remained in the reaction are removed, so that the purity of titanium silicon carbide in the etched product is ensured to be about 89-95%, and a large number of other derivatives can be avoided; and the layering is more obvious by controlling the rising rate of the reaction temperature and the reaction time, and the titanium silicon carbide is uniformly layered, so that the titanium silicon carbide with a uniform laminated structure is obtained by etching.

Wherein the halide salt may be at least one selected from sodium chloride, potassium chloride and the like, without limitation. The etchant may be one of Lewis acids (CuCl₂、CoCl₂、ZnCl₂、FeCl₃、NiCl₂、AgCl、FeCl₂、CdCl₂, etc.). Specifically, in one example, etching the titanium silicon carbide may include: uniformly mixing titanium silicon carbide raw materials, sodium chloride and potassium chloride according to the ratio of 1:5:5, and placing the prepared mixed solution into a sodium chloride salt bed; and secondly, gradually raising the temperature in vacuum, namely raising the temperature at the rate of 150-200 ℃ per hour, wherein as the temperature is raised, salts such as sodium chloride with low melting point become liquid, titanium silicon carbide powder is gradually layered in vacuum, and reacting for 3 hours at 1200 ℃ to generate laminated titanium silicon carbide. And then FeCl ₂ is added when the temperature is reduced by 600 ℃, etching reaction is carried out on the mixture and phases generated in molten salt, after 0.5h of reaction, cooling is carried out at normal temperature, after cooling to the room temperature, redundant salts are filtered out, and drying is carried out under vacuum, so that the uniform laminated titanium silicon carbide powder is finally obtained.

In one embodiment, the method for preparing the titanium silicon carbide modified material may further comprise:

The titanium silicon carbide with the laminated ordered hole structure is subjected to polydopamine modification to obtain polydopamine modified titanium silicon carbide, so that polydopamine and titanium silicon carbide are utilized to have similar open pore structures with high surface area and average interlayer spacing, covalent bonding between hole joints can be well maintained through polydopamine modification, covalent bonding at the hole joints of the titanium silicon carbide is not easy to break, stability of the hole joints of the microstructure of the titanium silicon carbide is improved, overall morphology and laminated ordered hole structures of the titanium silicon carbide can be well maintained through polydopamine modification, and influence on the laminated ordered hole structures of the titanium silicon carbide due to temperature and other environmental adjustment in the subsequent preparation process is prevented.

In the embodiment, the polydopamine monomer and the titanium silicon carbide can be mixed into a disperse phase according to the mass ratio of 1-1-4:1, the polydopamine monomer is gradually increased at 20-30 ℃ and deposited on the surface of the titanium silicon carbide, and polydopamine modification on the titanium silicon carbide is realized.

More preferably, the mass ratio of polydopamine monomer to titanium silicon carbide may be 3:1.

The paraffin particles are filled in the titanium silicon carbide cavity with the laminated ordered cavity structure, and then the heat pressing densification treatment is carried out, so that the titanium silicon carbide modified material is obtained, and the heat conduction property of the titanium silicon carbide can be improved by filling the paraffin wax type heat conduction substance in the titanium silicon carbide cavity, as shown in fig. 6, the heat conduction rate of the titanium silicon carbide modified material (namely the uniformly laminated expanded Ti ₃SiC₂ in fig. 6) of the embodiment is improved by about 30 percent compared with that of the common Ti ₃SiC₂, and the heat conduction rate of the titanium silicon carbide modified material is up to 6W/m ²/K; the paraffin particles are embedded in the cavity, so that the titanium silicon carbide can also maintain the cavity state under the condition of external pressure, the volume reduction in the subsequent hot pressing process can be avoided, the cavity state change can be avoided, the laminated ordered cavity structure of the uniformly laminated titanium silicon carbide is reserved, the wave absorbing performance and the heat conducting performance of the titanium silicon carbide can be well maintained, and the paraffin is modified among the uniformly laminated expanded titanium silicon carbide powder layers after being melted, so that the uniformly laminated expanded titanium silicon carbide realizes a continuous network structure on a long scale.

Preferably, the paraffin particles have a size smaller than the size of the cavity so that the paraffin particles can meet the requirements for entering the cavity. Specifically, the length of the paraffin particles may be 400nm or less, and the width and height of the paraffin particles may be 210nm or less.

To increase the uniformity of the paraffin particle packing, the paraffin particles may be spherical particles. Of course, in other embodiments, the paraffin particles may also be conical particles, lamellar particles, or columnar particles, etc.

In a specific example, the step of filling paraffin particles in the cavities of the titanium silicon carbide with the laminated ordered cavity structure and performing hot-pressing densification to obtain the titanium silicon carbide modified material may include: 10g of uniform lamination expanded titanium silicon carbide powder and 1-2g of paraffin microspheres are taken, firstly, 10g of paraffin microspheres are heated to be gelatinous, then titanium silicon carbide with a lamination ordered hole structure is added and is continuously stirred, specifically, the paraffin microspheres are self-assembled into holes among the poly-dopamine modified uniform lamination expanded titanium silicon carbide powder layers, the paraffin microspheres are modified among the uniform lamination expanded titanium silicon carbide powder layers after being melted, and finally, hot-pressing densification is carried out, so that the uniform lamination expanded titanium silicon carbide realizes a continuous network structure on a long scale, and the interconnected porous structure of the uniform lamination titanium silicon carbide powder in the composite material is reserved. It is preferable to perform the vibration treatment during stirring of the titanium silicon carbide having the stacked ordered pore structure and the paraffin particles in order to enhance the filling effect of the paraffin particles.

The application also provides a device comprising the wave absorbing material of the application. The device may be a wave absorbing device or a heat dissipating device.

Alternatively, the device may be a wave absorbing film 10, so that electromagnetic waves of 5.8GHz can be absorbed substantially by the wave absorbing film 10 made of the composite wave absorbing material of the present application, and electromagnetic waves of other frequency bands can be absorbed.

Alternatively, as shown in fig. 7, the wave-absorbing film 10 may include a wave-absorbing shielding layer 11 made of the above-described composite wave-absorbing material.

Further, the wave-absorbing film 10 may further include two insulating layers 12, and the two insulating layers 12 are disposed on opposite sides of the wave-absorbing shielding layer 11.

One of the insulating layers 12 may be an adhesive insulating layer and the other insulating layer 12 may be a non-adhesive insulating layer. Of course, in other embodiments, both insulating layers 12 of the wave-absorbing film 10 may be adhesive insulating layers.

Optionally, the device may be a shielding wave-absorbing film, so that electromagnetic waves of 5.8GHz are substantially absorbed by the shielding wave-absorbing film made of the composite wave-absorbing material of the present application, and electromagnetic waves of other frequency bands can be absorbed and/or shielded.

Wherein, the shielding wave-absorbing film may include a mesh shielding layer and an electromagnetic wave-absorbing layer. The mesh-shaped shielding layer may include a through hole as a shielding gap such that the mesh-shaped shielding layer can shield a portion of the electromagnetic wave, which may pass through the gap of the mesh-shaped shielding layer to the wave-absorbing layer to absorb the portion of the electromagnetic wave through the wave-absorbing layer, and the mesh-shaped shielding layer and the wave-absorbing layer may complementarily absorb the electromagnetic wave.

Optionally, the shielding wave absorbing performance of the shielding wave absorbing film can be adjusted by adjusting the number of layers of the metal shielding layer, the density of the metal shielding layer and the number of layers of the electromagnetic wave absorbing layer, so that the shielding wave absorbing film can be flexibly applied to different scenes, and meanwhile, the electromagnetic compatibility problem can be more effectively solved.

In one embodiment, as shown in fig. 8, the shielding and wave-absorbing film 20 may include at least two electromagnetic wave-absorbing layers 21 and a mesh-shaped shielding layer 22. The mesh-shaped shielding layer 22 is disposed between two adjacent electromagnetic wave absorbing layers 21, and two open ends of the through holes 221 of the mesh-shaped shielding layer 22 face the two electromagnetic wave absorbing layers 21 adjacent to the mesh-shaped shielding layer 22 in a one-to-one correspondence.

When the shielding wave-absorbing film 20 includes a wave-absorbing material having a laminated ordered pore structure, electromagnetic waves are absorbed by reflection at the inside of the laminated ordered pore structure a plurality of times, so that when the electromagnetic waves are incident into the electromagnetic wave-absorbing layer 21 made of a composite wave-absorbing material having a uniform laminated ordered pore structure, part of the electromagnetic waves are reflected back by the electromagnetic wave-absorbing layer 21 on the surface, thereby reducing the amount of the electromagnetic waves entering the inside of the object; and is shielded by the mesh shielding layer 22 even if there is an electromagnetic wave absorbing layer 21 through the surface of which electromagnetic waves pass; even if electromagnetic waves pass through the electromagnetic wave absorbing layer 21 and the mesh shielding layer 22 on the surface, the electromagnetic wave absorbing layer 21 arranged on the other side of the mesh shielding layer 22 is reflected back through multiple reflection and absorption in the laminated ordered pore structure, so that the reflection and absorption capacity of the shielding wave absorbing film 20 on electromagnetic waves can be greatly improved through alternate reflection of at least two electromagnetic wave absorbing layers 21 made of composite wave absorbing materials of the uniformly laminated ordered pore structure and mutual matching with the mesh shielding layer 22, thereby greatly reducing the quantity of the electromagnetic waves entering the object through the shielding wave absorbing film 20, namely greatly improving the reflection and absorption effect of the shielding wave absorbing film 20 on the electromagnetic waves.

In this embodiment, as shown in fig. 9, in order to prevent the mesh-type shielding layer 22 from causing damage to the device during use, an insulating treatment may be performed on the mesh-type shielding layer 22, for example, an insulating layer 23 may be laid on the surface of the mesh-type shielding layer 22, that is, an insulating layer 23 may be disposed between the mesh-type shielding layer 22 and the electromagnetic wave absorbing layer 21.

Considering that the electromagnetic wave absorbing layer 21 is provided on both opposite sides of the mesh-shaped shielding layer 22, the insulating layer 23 may not be provided between the mesh-shaped shielding layer 22 and the electromagnetic wave absorbing layer 21, i.e., in the case where the electromagnetic wave absorbing layer 21 is provided on both opposite sides of the mesh-shaped shielding layer 22, the insulating treatment may not be performed on the mesh-shaped shielding layer 22, in which case the heat dissipation performance of the shielding wave absorbing film 20 is better. Thus, the mesh-shaped shielding layer 22 can be prepared in advance, and then the composite wave-absorbing material is laid on the front and back sides of the mesh-shaped shielding layer 22 to serve as the electromagnetic wave-absorbing layer 21, so that the wave-absorbing shielding film 20 with wave-absorbing shielding performance in a wider frequency range can be obtained.

Further, as shown in fig. 8, an insulating layer 23 may be disposed on a side of the electromagnetic wave absorbing layer 21 away from the mesh-shaped shielding layer 22, so that the shielding wave absorbing film 20 may be subjected to a specific insulating treatment so as to be applied to a circuit surface, and further, the insulating distance of the shielding wave absorbing film 20 may be reinforced so as to be applied to a circuit board.

To facilitate the use of the shielding absorbing film 20, the insulating layer 23 may be adhesive, such as an acrylic insulating layer, a rubber-like insulating layer.

In another embodiment, as shown in fig. 10, the shielding and absorbing film 20 may include one electromagnetic wave absorbing layer 21 and a mesh shielding layer 22.

In order to prevent the mesh-like shielding layer 22 from causing damage to the device during use, an insulating treatment may be performed on the mesh-like shielding layer 22 and/or the electromagnetic wave absorbing layer 21.

In a specific example, as shown in fig. 10, the shielding and absorbing film 20 may include a mesh-like shielding layer 22, an insulating layer 23, an electromagnetic wave absorbing layer 21, and an adhesive insulating layer 24, which are laminated in this order.

In another specific example, as shown in fig. 11, the shielding and wave-absorbing film 20 may include a non-adhesive insulating layer 25, an electromagnetic wave-absorbing layer 21, a mesh-shaped shielding layer 22, and an adhesive insulating layer 24, which are laminated in this order.

In the shielding wave-absorbing film 20, the electromagnetic wave-absorbing layer 21 of the shielding wave-absorbing film 20 may be made of the composite wave-absorbing material of the present application.

As for the electromagnetic wave-absorbing layer 21, the method of manufacturing the electromagnetic wave-absorbing layer 21 by the composite wave-absorbing material is not limited.

For example, it may be formed by dry pressing, and specifically, an appropriate amount of the composite wave-absorbing material may be directly pressed to form the electromagnetic wave-absorbing layer 21.

For example, the electromagnetic wave absorbing layer 21 may be obtained by wet curing, specifically, by adding a coagulant to a solution of a suitable amount of a composite wave absorbing material and curing the solution of the wave absorbing material with the coagulant.

For example, the electromagnetic wave absorbing layer 21 can be produced by a printing method such as screen printing, specifically, a suitable amount of the composite wave absorbing material can be made into a solution, then the wave absorbing material solution is printed on the surface of the mesh-shaped shielding layer 22 by a printing method such as screen printing, and then the composite wave absorbing material solution printed on the surface of the mesh-shaped shielding layer 22 is cured.

For the mesh-shaped shielding layer 22, the mesh-shaped shielding layer 22 may include at least one of a metal shielding layer, a ferrite shielding layer, and the like.

The metallic shield may be a woven mesh of metallic wires, for example, the mesh shield 22 may be woven from metallic wires automatically.

Wherein, the metal wire can be made of iron, copper, aluminum and other materials.

The wire diameter of the metal wire is not limited and may be determined comprehensively according to factors such as the cost and shielding performance of the shielding wave-absorbing film 20. More preferably, the wire diameter of the metal wire may be 0.05mm to 0.20mm. Further, the wire diameter of the metal wire may be 0.10mm.

In other embodiments, the metal shielding layer may also be obtained by perforating a non-porous metal layer.

In order to be suitable for practical application environments and meet shielding performance requirements in different environments, the shielding performance of the mesh shielding layer 22 is adjusted by adjusting the number of layers and the size of the through holes 221, so that the cost input of materials can be controlled as much as possible, and the consumption of unnecessary materials is reduced.

Wherein, the size of the through hole 221 and the shielding wave band of the shielding absorbing film 20 may be inversely related. I.e., the shielding wave band of the shielding absorbing film 20 is high, the size of the through hole 221 may be set smaller.

The shape of the through hole 221 is not limited, and may be square or triangular, or honeycomb, for example.

In addition, the device can also be a wave-absorbing radiator, so that the wave-absorbing radiator is manufactured by compounding the wave-absorbing material and the heat-conducting material, and the device has better wave-absorbing effect and heat-radiating effect.

In an embodiment, as shown in fig. 12, the wave-absorbing radiator 30 may include a wave-absorbing member 31 and a heat dissipating member 32 embedded in the wave-absorbing member 31, and further the wave-absorbing member 31 completely encapsulates the heat dissipating member 32, and the embodiment makes the wave-absorbing member 31 and the heat dissipating member 32 cooperate in a manner of embedding and filling complementation, so that the wave-absorbing radiator 30 has both excellent wave-absorbing performance and heat dissipating performance, and may be applied to electronic devices with higher heat dissipating requirements, to improve the heat dissipating performance of the electronic devices and suppress electromagnetic wave interference, and may also be used as a space coupling for isolating crosstalk between signals and avoiding inductive devices, thereby solving the problem that the wave-absorbing member and the heat dissipating member cannot be compatible, greatly reducing space, and being beneficial to the integration and miniaturization progress of the electronic devices.

The application is not limited to the choice of the heat sink 32, and may be a heat sink pad, a metal sheet metal part, heat conductive silica gel, heat conductive silicone, or the like. Among them, when the heat sink 32 is preferably a heat sink pad, a heat conductive silicone grease, or the like, the wave-absorbing heat sink 32 obtained by the combination of the wave-absorbing member 31 has excellent flexibility, ductility, or the like.

Alternatively, the heat sink 32 is made of a heat sink material.

The preparation process of the heat dissipation material can be as follows: preparing raw materials, wherein the raw materials comprise heat conducting powder, and the heat conducting powder can comprise one or a mixture of more of aluminum oxide, aluminum, zinc oxide, aluminum hydroxide, magnesium hydroxide, boron nitride, ceramic and the like, and the particle size is 0.1-100 mu m; the preferable proportion of the heat conducting raw materials is 1:1:1:1, but the heat radiating capability is further improved by increasing the proportion of a certain raw material, the selected heat conducting raw materials are dissolved in 1:1 water, a proper amount of adhesive vinyl silicone oil and hydrogen-containing silicone oil are added into the water, stirring is carried out for 1 h-2.0 h at the temperature of 50-150 ℃ under the vacuum of 80 kPa-90 kPa, the rotating speed is 75 rpm-100 rpm, the stirring is continued for 3 h-4 h, and finally the heat radiating material is obtained by cooling in a prepared mould.

The process of preparing the heat sink 32 from a heat sink material may include: the heat sink material and raw rubber are mixed and subjected to mixing, plasticating, pressing and molding processes to obtain the heat sink 32.

In a specific example, firstly smelting raw rubber, cutting and breaking the raw rubber into small blocks after the raw rubber is baked at 70-80 ℃, then heating the small blocks to 80-90 ℃ in an antioxidant container to obtain gel, adding a heat dissipation material into water to prepare gel, uniformly stirring the raw rubber at the stirring speed of 500r/min, and adding a compounding agent into the heat dissipation material and the raw rubber according to the proportion range of 1:1-4:1, wherein the compounding agent is paraffin; the gel-like heat sink material mixture is used to prepare a heat sink sheet of a specific thickness, and the heat sink 32 is obtained after cooling and molding. Alternatively, the complexing agent may be present in an amount of 1/5 to 1/3.

The wave absorbing member 31 of this embodiment may be made of the composite wave absorbing material described above.

In this embodiment, after the heat sink 32 is manufactured, the heat sink 32 may be laid flat in a mold, and then a mixture of gel-like composite wave-absorbing materials may be added to the mold and pressed to completely cover the heat sink 32, and then cooled at normal temperature to obtain the embedded wave-absorbing heat sink 30.

The gel-like composite wave-absorbing material may be obtained by mixing, kneading and plasticating a composite wave-absorbing material and raw rubber.

Optionally, raw rubber is smelted, the raw rubber is dried and softened in an environment of 70-80 ℃ and then cut and broken into small blocks, then the small blocks are heated to 80-90 ℃ in an antioxidant container to obtain gel, a composite wave-absorbing material is added into water to prepare gel, the raw rubber is uniformly stirred at a stirring speed of 500r/min, and a compounding agent is added into the raw rubber according to a proportion range of 1:1-5:1, wherein the compounding agent can be paraffin, so that a mixture of the gel composite wave-absorbing material is obtained. Alternatively, the complexing agent may be present in an amount of 1/5 to 1/3.

In another embodiment, as shown in fig. 13, the wave-absorbing radiator 30 may include a radiator 32 and a wave-absorbing member 31 embedded in the radiator 32, that is, the radiator 32 completely encloses the wave-absorbing member 31, and the wave-absorbing radiator 30 may be applied in an environment with low heat dissipation requirements.

The preparation process of the wave absorbing member 31 and the heat dissipating member 32 can be as shown in the above embodiments, and will not be described herein.

The wave absorbing member 31 may be prepared in a honeycomb shape.

The above embodiment mixes the elastic raw rubber with the wave-absorbing/heat-dissipating material, thereby improving the ductility and flexibility of the material and improving the structural stability of the wave-absorbing heat sink 30.

Fig. 14 shows a schematic diagram of the insertion loss curve of the wave-absorbing radiator 30 according to the two embodiments. As shown in fig. 14, the wave-absorbing radiator 30 of the two embodiments has an insertion loss of 21dB to 27dB at 30Mhz-18Ghz, i.e., has a good wave-absorbing performance.

In other implementations, the device described above may also be a wave absorbing cable.

In an embodiment, the wave-absorbing layer may be made of the wave-absorbing material, and the wave-absorbing layer may be wrapped around the wire core, so as to obtain the wave-absorbing cable.

In another embodiment, the wave-absorbing material and the cable raw material may be mixed, and the wave-absorbing cable is directly manufactured from the mixed raw material.

The advantageous effects of the present application are further illustrated below with reference to examples.

In order to make the technical problems, technical schemes and beneficial effects solved by the embodiments of the present application more clear, the following will be described in further detail with reference to the embodiments and the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses. All other embodiments, which can be made by a person skilled in the art based on the embodiments of the application without any inventive effort, are intended to fall within the scope of the application.

Comparative example 1

Uniformly mixing titanium silicon carbide raw materials, sodium chloride and potassium chloride according to the ratio of 1:5:5, and placing the prepared mixed solution into a sodium chloride salt bed; and secondly, gradually raising the temperature in vacuum, specifically raising the temperature at a rate of 150 ℃ per hour, enabling low-melting sodium chloride and other salts to become liquid along with the temperature rise, gradually layering titanium silicon carbide powder in vacuum, and reacting for 3 hours at 1200 ℃ to generate laminated titanium silicon carbide. And then FeCl ₂ is added when the temperature is reduced by 600 ℃, etching reaction is carried out on the mixture and phases generated in molten salt, after 0.5h of reaction, cooling is carried out at normal temperature, after cooling to the room temperature, redundant salts are filtered out, and drying is carried out under vacuum, so that the uniform laminated titanium silicon carbide powder is finally obtained.

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, and the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, and the temperature is maintained at 150 ℃ for 1.5h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material. An electron microscopic image of the titanium silicon carbide modified material prepared by the method of this comparative example is shown in fig. 15.

Example 1

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, the temperature is respectively kept at 100 ℃ for 30 minutes, and the temperature is maintained at 150 ℃ for 1h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material. An electron micrograph of the obtained titanium silicon carbide powder is shown in FIG. 2.

Example 2

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, the temperature is respectively kept at 95 ℃ for 30 minutes, and the temperature is maintained at 150 ℃ for 1h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material.

Example 3

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, the temperature is respectively kept at 100 ℃ for 1h, and the temperature is kept at 145 ℃ for 1h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material. An electron microscopic image of the titanium silicon carbide modified material prepared by the method of this example is shown in fig. 16.

Example 4

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, the temperature is respectively kept at 105 ℃ for 1h, and the temperature is maintained at 150 ℃ for 1h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material.

Example 5

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, the temperature is respectively kept at 100 ℃ for 1h, and the temperature is maintained at 155 ℃ for 0.5h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material.

Example 6

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 10 ℃ per minute, the temperature is respectively kept at 100 ℃ for 30 minutes, and the temperature is maintained at 150 ℃ for 1h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material.

Example 7

Uniformly mixing titanium silicon carbide raw materials, sodium chloride and potassium chloride according to the ratio of 1:5:5, and placing the prepared mixed solution into a sodium chloride salt bed; and secondly, gradually raising the temperature in vacuum, specifically raising the temperature at the rate of 125 ℃ per hour, enabling low-melting sodium chloride and other salts to become liquid along with the temperature rise, gradually layering titanium silicon carbide powder in vacuum, and reacting for 3 hours at 1200 ℃ to generate laminated titanium silicon carbide. And then FeCl ₂ is added when the temperature is reduced to 590 ℃, etching reaction is carried out on the mixture and a phase generated in molten salt, after 0.5h of reaction, cooling is carried out at normal temperature, after cooling to the room temperature, redundant salt is filtered out, and drying is carried out under vacuum, so that the uniform laminated titanium silicon carbide powder is finally obtained.

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, the temperature is respectively kept at 100 ℃ for 30 minutes, and the temperature is maintained at 150 ℃ for 1h; and (5) removing excessive sodium salt through filtration after subsequent cooling, and finally obtaining the titanium silicon carbide modified material.

Example 8

Uniformly mixing titanium silicon carbide raw materials, sodium chloride and potassium chloride according to the ratio of 1:5:5, and placing the prepared mixed solution into a sodium chloride salt bed; and secondly, gradually raising the temperature in vacuum, specifically raising the temperature at the rate of 200 ℃ per hour, enabling low-melting sodium chloride and other salts to become liquid along with the temperature rise, gradually layering titanium silicon carbide powder in vacuum, and reacting for 3 hours at 1200 ℃ to generate laminated titanium silicon carbide. And then adding FeCl ₂ when the temperature is reduced by 610 ℃, carrying out etching reaction with a phase generated in molten salt, cooling at normal temperature after 0.5h of reaction, filtering out redundant salt after cooling to the room temperature, and drying under vacuum to finally obtain the uniform laminated titanium silicon carbide powder.

Example 9

10G of the uniformly laminated titanium silicon carbide powder was added to 150ml of a 3:1 mixed solution of water and ethanol, and stirred uniformly at 300r/min for 3 hours. Then, the uniform laminated titanium silicon carbide colloid dispersion liquid is obtained by ultrasonic dispersion for 1 h. Then, 5g of sodium bicarbonate was added, and the mixture was stirred uniformly at 300r/min for 1 hour, and dried at room temperature to obtain a solid mixture of uniformly laminated titanium silicon carbide and sodium bicarbonate. The solid mixture is put into a reducing atmosphere of hydrogen and nitrogen for expansion reduction, the temperature is gradually increased to 150 ℃ from room temperature during the expansion reduction, the temperature increasing rate is controlled to be 5 ℃ per minute, the temperature is respectively kept at 100 ℃ for 30 minutes, and the temperature is maintained at 150 ℃ for 1h; and (5) removing redundant sodium salt through filtration after subsequent cooling, and finally obtaining the uniform lamination puffed titanium silicon carbide powder.

And modifying the titanium silicon carbide with the laminated ordered hole structure by polydopamine to obtain the titanium silicon carbide modified material.

Example 10

And modifying the polydopamine on the titanium silicon carbide with the laminated ordered hole structure to obtain polydopamine modified titanium silicon carbide.

Filling spherical paraffin particles with the particle size of 100nm into the polydopamine modified titanium silicon carbide, and performing hot-pressing densification treatment to obtain the titanium silicon carbide modified material.

Example 11

Filling spherical paraffin particles with the particle size of 300nm into the polydopamine modified titanium silicon carbide, and performing hot-pressing densification treatment to obtain the titanium silicon carbide modified material.

Example 12

Filling flaky paraffin particles with the particle size of 100nm into the polydopamine modified titanium silicon carbide, and performing hot-pressing densification to obtain the titanium silicon carbide modified material.

The performance characterization method comprises the following steps:

(1) Insertion loss test: reference GB/T32596, test absorption bandwidth and insertion loss;

(2) And (3) heat conduction rate test: referring to GB/T10294, the heat conduction rate is tested;

(3) The titanium silicon carbide modified materials prepared in the above comparative examples and examples were subjected to heat press treatment, and then the heat-press-treated materials were subjected to post-heat press insertion loss and post-heat press heat conduction rate measurement by using the above insertion loss test method and heat conduction rate test method.

Table 1 test parameter tables for each of examples and comparative examples

As can be seen from the data of table 1, the comparative examples and comparative example 1 can provide the wave-absorbing material with a stacked ordered cavity structure by controlling the appropriate swelling reduction temperature and reaction time; compared with the wave-absorbing material without the laminated ordered hole structure, the wave-absorbing material with the laminated ordered hole structure has excellent wave-absorbing performance and heat dissipation performance.

Further, as is clear from comparative examples 1 and 9, by modifying the wave-absorbing material with polydopamine, the wave-absorbing performance of the wave-absorbing material can be improved, and the influence of hot pressing on the wave-absorbing performance of the wave-absorbing material can be reduced.

As is clear from comparative examples 9 to 12, by filling the polydopamine-modified titanium silicon carbide material with paraffin particles, the heat radiation performance of the wave-absorbing material can be significantly improved, and the influence of hot pressing on the wave-absorbing performance of the wave-absorbing material can be further reduced.

The foregoing description is only of embodiments of the present application, and is not intended to limit the scope of the application, and all equivalent structures or equivalent processes using the descriptions and the drawings of the present application or directly or indirectly applied to other related technical fields are included in the scope of the present application.

Claims

1. The wave absorbing material is characterized by comprising titanium silicon carbide, wherein the titanium silicon carbide is of a laminated ordered cavity structure.

2. The wave absorbing material of claim 1, wherein the cavities in the titanium silicon carbide are elliptical, the major axis of the elliptical is 200nm to 400nm, and the minor axis of the elliptical is 130nm to 210nm.

3. The wave absorbing material of claim 1, wherein the titanium silicon carbide is covalently bonded at junctions between the voids.

4. A method for preparing a wave-absorbing material, the method comprising:

Providing a titanium silicon carbide raw material;

Etching the titanium silicon carbide raw material to obtain uniform laminated titanium silicon carbide;

Mixing the uniformly laminated titanium silicon carbide and a bulking agent to obtain a uniform mixture;

And placing the uniform mixture in a reducing atmosphere, heating to 95-105 ℃ and preserving heat for 0.3-1 h, and then heating to 145-155 ℃ and preserving heat for 0.5-1.5 h to obtain the wave-absorbing material.

5. The method according to claim 4, wherein said subjecting the homogeneous mixture to a reducing atmosphere to a temperature of 95 ℃ to 105 ℃ and a heat preservation of 0.3h to 1h, followed by a temperature of 145 ℃ to 155 ℃ and a heat preservation of 0.5h to 1.5h to obtain the wave-absorbing material comprises:

placing the uniform mixture in a reducing atmosphere, heating to 100 ℃ and preserving heat for 0.5h, then heating to 150 ℃ and preserving heat for 1h to obtain titanium silicon carbide with a laminated ordered hole structure;

and (3) doping paraffin particles between layers of titanium silicon carbide with a laminated ordered hole structure, and performing hot-pressing densification treatment to obtain the titanium silicon carbide modified material.

6. The method according to claim 5, wherein the steps of doping paraffin particles between layers of titanium silicon carbide having a layered ordered cavity structure, and performing hot-press densification to obtain the titanium silicon carbide modified material include:

polydopamine modification is carried out on the titanium silicon carbide with the laminated ordered cavity structure, and the polydopamine modified titanium silicon carbide is obtained;

And doping paraffin particles between the layers of the polydopamine modified titanium silicon carbide, and performing hot-pressing densification treatment to obtain the titanium silicon carbide modified material.

7. The preparation method of claim 6, wherein the interlayer of the polydopamine modified titanium silicon carbide is doped with paraffin particles, and then the interlayer is subjected to hot pressing densification treatment to obtain the titanium silicon carbide modified material, and the preparation method comprises the following steps:

And heating paraffin particles to gel, mixing with the polydopamine modified titanium silicon carbide, and stirring to obtain the titanium silicon carbide modified material.

8. The method of preparing according to claim 4, wherein said mixing the homogeneously layered titanium silicon carbide with the bulking agent provides a homogeneous mixture comprising:

Dispersing the uniformly laminated titanium silicon carbide in a solution to prepare a colloid dispersion liquid;

adding sodium bicarbonate into the colloidal dispersion, stirring for a period of time, and drying to obtain the uniform mixture.

9. The method of claim 4, wherein etching the titanium silicon carbide material to obtain a uniform stack of titanium silicon carbide comprises:

Mixing the titanium silicon carbide raw material and halogenated salt, and then placing the mixture in a salt bed of the halogenated salt;

And heating the salt bed and the titanium silicon carbide raw material in the salt bed to 1150-1200 ℃ at a heating rate of 150-200 ℃/h in vacuum, preserving heat for 2-4 h, cooling to 590-610 ℃, adding an etchant, reacting for 10 min-1 h, and cooling to room temperature to obtain the uniform laminated titanium silicon carbide.

10. A device comprising the wave-absorbing material of any one of claims 1 to 3; or comprising the titanium silicon carbide modified material produced by the method of any one of claims 4 to 9.