A single cone lightweight high power absorbing material and a manufacturing method thereof

Abstract

The present invention belongs to the field of wave-absorbing materials, and provides a single-cone lightweight high-power wave-absorbing material and a manufacturing method thereof. The wave-absorbing material comprises an outer shell, an inner core and a wave-transmitting cap, wherein the outer shell is in the shape of a regular tetrahedron, and is assembled and formed by a three-layer composite wave-absorbing flame-retardant substrate formed by a conductive layer-flame-retardant board-conductive layer, and the angle between the two opposite sides of the outer shell is 16° to 18°, and microwave radiation heat dissipation holes are provided on the outer shell, and the inner core is arranged at the bottom of the outer shell, and the inner core is an array formed by a plurality of regular tetrahedrons, and is assembled and formed by a double-layer composite wave-absorbing flame-retardant substrate formed by a flame-retardant paper-conductive layer. The single-cone lightweight high-power wave-absorbing material of the present invention is composed of an assembled flame-retardant board outer shell and a flame-retardant paper angle pyramid inner core, and its production process is greatly reduced compared with conventional non-woven flame-retardant materials, and its production efficiency is significantly improved, and its quality and appearance consistency can meet the requirements, so that the overall performance and aesthetics of the darkroom are guaranteed.

Description

Technical Field

[0001] The invention belongs to the field of wave absorbing materials, and in particular relates to a single-cone lightweight high-power wave absorbing material and a manufacturing method thereof. Background Art

[0002] With the development of modern science and technology, the impact of electromagnetic radiation on the environment is increasing. At airports, flights are delayed due to electromagnetic interference and cannot take off; in hospitals, mobile phones often interfere with the normal operation of various electronic diagnostic and treatment equipment. Therefore, controlling electromagnetic pollution and finding a material that can resist and weaken electromagnetic radiation - absorbing materials, has become a major topic in materials science.

[0003] At present, the commonly used absorbing materials in my country mainly include absorbing materials based on soft polyurethane foam plastics and flame-retardant absorbing materials based on non-woven fabrics. However, the above two absorbing materials have some shortcomings in production and application: (1) Although the soft polyurethane foam plastic absorbing material has been flame-retardant treated, its flame retardant performance can only meet B2 level, and its power resistance performance does not exceed 1500W / m 2 Even if the aperture is enlarged to 5mm, its power resistance performance can reach up to 3000W / m 2 , cannot withstand power density ≥ 4000W / m 2 At the same time, as the height of the polyurethane foam absorbing material continues to increase, its cone tip will be more likely to sag as its own weight continues to increase, affecting the overall performance of the darkroom; (2) Although the multi-angle cone non-woven flame-retardant absorbing material can solve the problems of poor flame retardancy, insufficient power resistance, elbows, and powder loss of polyurethane foam absorbing materials, the material has many processes in the production process and is purely handmade. Its quality and appearance consistency cannot be guaranteed, affecting the overall performance and aesthetics of the darkroom. Summary of the invention

[0004] The purpose of the present invention is to address the problem that the production process of polygonal pyramid non-woven flame-retardant absorbing materials is multiple and the consistency of appearance and performance cannot be guaranteed. A single-cone lightweight high-power absorbing material and a manufacturing method thereof are proposed. The absorbing material has the characteristics of rapid production and excellent absorbing performance and power resistance.

[0005] The technical solution adopted by the present invention is as follows.

[0006] A single-cone lightweight high-power absorbing material comprises an outer shell, an inner core and a wave-transmitting cap. The outer shell is in the shape of a regular tetrahedron and is assembled from a three-layer composite wave-absorbing flame-retardant substrate formed by a conductive layer, a flame-retardant board and a conductive layer. The angle between two opposite sides of the outer shell is 16° to 18°. Microwave radiation heat dissipation holes are provided on the outer shell. The inner core is arranged at the bottom of the outer shell. The inner core is an array formed by a plurality of regular tetrahedrons and is assembled from a double-layer composite wave-absorbing flame-retardant substrate formed by flame-retardant paper and a conductive layer. The wave-transmitting cap is arranged at the top of the outer shell.

[0007] In the above technical solution, the single-cone lightweight high-power absorbing material further includes a metal bracket for hanging the absorbing material, and the metal bracket is arranged at the bottom of the outer shell.

[0008] In the above technical solution, the flame retardant performance of the flame retardant board meets the A1 standard, and after the conductive layer is coated on its surface, the surface resistance is 300-500 ohms / square.

[0009] In the above technical solution, the flame retardant board is made of modified foamed polypropylene material or glass magnesium board with a thickness of 2-3 mm.

[0010] In the above technical solution, after the surface of the flame-retardant paper is coated with a conductive layer, the surface resistance is less than 300 ohms / square.

[0011] In the above technical solution, the flame retardant paper is made of asbestos fiber and has a thickness of 0.2-0.4 mm.

[0012] In the above technical solution, the wave-transmitting cap is made of polypropylene.

[0013] The present invention also provides a method for manufacturing a single-cone lightweight high-power absorbing material, the method comprising:

[0014] (1) Manufacturing an absorbing material outer shell substrate assembly sheet; first, cutting a flame retardant board into triangular sheets, applying a layer of conductive liquid on the surface of the triangular sheet, drying, applying the same amount of conductive liquid on the other side of the triangular sheet, drying, the drying temperature is 50° C. to 70° C., the drying time is 10 min to 15 min, and the conductive film thickness is 0.1 mm to 0.2 mm, thereby forming an absorbing material outer shell substrate assembly sheet;

[0015] (2) manufacturing an inner core of an absorbing material; first, a layer of conductive liquid is applied to the surface of asbestos fiber paper, and the paper is dried at a temperature of 50° C. to 70° C. for 10 min to 15 min to form a composite substrate for the inner core of the absorbing material; the composite substrate is cut and assembled into a regular tetrahedron, and then a plurality of regular tetrahedrons are bonded into a pyramid array to form an inner core of the absorbing material;

[0016] (3) Assembling a single cone lightweight high-power absorbing material; opening microwave radiation heat dissipation holes on the absorbing material outer shell substrate assembly sheet, bonding the absorbing material outer shell substrate assembly sheets with microwave radiation heat dissipation holes together to form a regular quadrangular pyramid outer shell, bonding the inner core and the metal bracket together with fireproof adhesive, and then bonding the metal bracket to the bottom of the outer shell with fireproof adhesive, and finally placing the wave-transmitting cap on the top of the outer shell and bonding it with fireproof adhesive.

[0017] The single-cone lightweight high-power absorbing material of the present invention is composed of an assembled flame-retardant board outer shell and a flame-retardant paper pyramid inner core. Its production process is greatly reduced compared with conventional non-woven flame-retardant materials, and the production efficiency is significantly improved, which meets the requirements of mass production. In addition, its quality and appearance consistency can meet the requirements, so that the overall performance and aesthetics of the darkroom are guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the single-cone lightweight high-power absorbing material of the present invention.

[0019] Figure 2 It is a three-dimensional schematic diagram of the single-cone lightweight high-power absorbing material of the present invention.

[0020] Figure 3 It is a schematic diagram of the outer shell in the present invention.

[0021] Figure 4 It is a schematic diagram of the inner core in the present invention.

[0022] Figure 5 It is a bottom view of the single-cone lightweight high-power absorbing material of the present invention.

[0023] Figure 6 It is a schematic diagram of the assembled pieces of the shell substrate of the flame retardant board of the absorbing material in this embodiment.

[0024] Figure 7 It is a schematic diagram of the wave-transmitting cap in the present invention.

[0025] Figure 8 Schematic diagram of the metal bracket in the present invention.

[0026] Fig. 9 This is a comparison chart of the electrical performance test of the absorbing material of the present invention.

[0027] Among them: 1. outer shell, 2. inner core, 3. wave-transmitting cap, 4. microwave radiation heat dissipation hole, 5. metal bracket. DETAILED DESCRIPTION

[0028] The specific implementation modes of the present invention are further described in detail below in conjunction with examples.

[0029] Example 1

[0030] like Figures 1 to 8 As shown, this embodiment provides a single-cone lightweight high-power absorbing material, including an outer shell 1, an inner core 2, a metal bracket 5 and a wave-transmitting cap 3. The outer shell 1 is in the shape of a regular quadrangular pyramid and is assembled and formed by a three-layer composite absorbing flame-retardant substrate formed by a conductive layer-a flame-retardant board-a conductive layer. The flame retardant performance of the flame retardant board meets the A1 standard. After the conductive layer is coated on its surface, the surface resistance is 300-500 ohms / square. The angle between the two opposite sides of the outer shell 1 is 16°~18°, which is obtained based on electromagnetic simulation data. It can be more conducive to the entry of electromagnetic waves into the interior of the material and is easy to assemble. The outer shell 1 is provided with microwave radiation heat dissipation holes 4. The metal bracket 5 is arranged at the bottom of the outer shell for hanging materials. The inner core 2 is arranged at the bottom of the outer shell and bonded to the metal bracket 5. The inner core 2 is an array formed by a plurality of regular tetrahedrons, and is assembled by a double-layer composite absorbing flame-retardant substrate formed by a flame-retardant paper-conductive layer. The flame-retardant paper is made of asbestos fiber with a thickness of 0.2-0.4mm. After the surface of the flame-retardant paper is coated with a conductive layer, the surface resistance is less than 300 ohms / square. The wave-transmitting cap 3 is arranged at the top of the outer shell, and the wave-transmitting cap is made of polypropylene.

[0031] In the above embodiment, the flame retardant board is a modified foamed polypropylene material or a glass magnesium board, and has a thickness of 2-3 mm.

[0032] The modified foamed polypropylene material is made of flame-retardant foamed polypropylene particles by hot pressing and welding, and the flame-retardant foamed polypropylene particles are obtained by stirring and drying a flame-retardant emulsion and foamed polypropylene particles in a mass ratio of 1:10 to 3:7 using a planetary mixer, and the flame-retardant emulsion is dispersed and ground with water, a dispersant, aluminum hydroxide, and a polyacrylic acid emulsion, wherein the mass ratio of the dispersant, aluminum hydroxide, and polyacrylic acid is between 1:5:5 and 1:7:3.

[0033] Example 2

[0034] This embodiment provides a method for manufacturing a single-cone lightweight high-power absorbing material, the method comprising:

[0035] (1) Manufacturing of absorbing material shell substrate assembly pieces

[0036] First, a 3mm thick high-power flame-retardant board is cut into triangular pieces by a cutting machine, and then transferred to a painting room to apply a layer of conductive liquid on its surface and dry it. The same amount of conductive liquid is applied to the other side of the triangular piece and dried at a temperature of 50°C for 10 minutes. The conductive film thickness is 0.1mm, forming an absorbing material flame-retardant board shell substrate assembly sheet, and its structure is shown in FIG. Figure 6 Since the flame retardant board has a certain thickness, it will be cut into Figure 6 Only the two shapes a and b can ensure the assembly effect.

[0037] (2) Manufacturing the inner core of the absorbing material

[0038] First, a layer of conductive liquid is applied on the surface of asbestos fiber paper with a thickness of 0.3 mm, and then dried at a temperature of 50°C for 10 minutes to form a composite substrate with a flame-retardant paper pyramid core of an absorbing material. The composite substrate is then transferred to a flat die-cutting machine and cut into a specific shape. The composite substrate of the specific shape is assembled into a regular tetrahedron with glue, and then multiple regular tetrahedrons are bonded into a pyramid array. The structure is shown in FIG. Figure 4 .

[0039] (3) Single cone lightweight high power absorbing material assembly

[0040] A microwave radiation heat dissipation hole is opened on the substrate assembly piece of the absorbing material shell body, and the absorbing material shell body substrate assembly piece with the microwave radiation heat dissipation hole is pressed Figure 6 The two types a and b are combined and bonded into a regular tetrahedral outer shell. The inner core and the metal bracket are bonded together with fireproof glue. The metal bracket is then bonded to the bottom of the outer shell with fireproof glue. Finally, the wave-transmitting cap is placed on the top of the outer shell and bonded with fireproof glue. Among them, the wave-transmitting cap is formed by bending the polypropylene material into a hat shape. The finally assembled single-cone lightweight high-power absorbing material has a base of 500mm*500mm and a height of 1600mm.

[0041] The single cone lightweight high power absorbing material manufactured in Example 2 was used for performance testing:

[0042] 1. Electrical performance test, the results are as follows Fig. 9 shown.

[0043] It can be seen from the figure that the electrical properties of the single-cone lightweight high-power absorbing material and the polygonal cone non-woven flame-retardant absorbing material are similar, indicating that the single-cone lightweight high-power absorbing material prepared by this method can ensure the electrical properties of the material.

[0044] 2. Power resistance performance test, the results are shown in the following table.

[0045] Table 1 Comparison of material power resistance performance test

[0046] Specification <![CDATA[Power resistance performance / W / m 2 > 1600mm high single cone lightweight high power absorbing material ≤4000 1600mm high polygonal pyramid polyurethane sponge absorbing material ≤1500 1600mm high polygonal pyramid non-woven fabric flame retardant wave absorbing material ≤4000

[0047] From the data in the table, it can be seen that the power resistance performance of the single-cone lightweight high-power absorbing material is similar to that of the polygonal cone non-woven flame-retardant absorbing material, and is better than that of the polyurethane sponge, indicating that the single-cone lightweight high-power absorbing material prepared by this method can ensure the power resistance performance of the material.

[0048] In summary, the single cone light-weight high-power absorbing material prepared by the method of the present invention has excellent absorbing performance and power resistance performance. At the same time, it is easier to produce than the multi-angle cone non-woven flame-retardant absorbing material and has better appearance consistency.

[0049] The present invention relates to a single-cone lightweight high-power absorbing material and a manufacturing method thereof, the essential feature of which is to apply a conductive layer on the surface of a flame-retardant board material, and then design the single-cone size through simulation according to the theoretical low-high frequency absorption performance of the material, adjust the thickness of the single cone, and design the size and structure of the inner core material to achieve the best absorption performance of the high and low bandwidth of the absorbing material. Since the fireproof board is used to replace the traditional non-woven fabric material, the flame-retardant treatment process of the non-woven fabric is reduced, the material appearance consistency is better, and the rapid production of the single-cone high-power absorbing material is achieved.

[0050] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, proportional scaling, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A single cone lightweight high power absorbing material, comprising an outer shell, an inner core and a wave-transmitting cap, characterized in that: The outer shell is in the shape of a regular tetrahedron, and is assembled and formed by a three-layer composite wave-absorbing flame-retardant substrate formed by a conductive layer-a flame-retardant board-a conductive layer. The flame-retardant board is made of a modified foamed polypropylene material or a glass magnesium board with a thickness of 2-3 mm. The modified foamed polypropylene material is made of flame-retardant foamed polypropylene particles by hot pressing and welding. The flame-retardant foamed polypropylene particles are obtained by mixing and drying a flame-retardant emulsion and foamed polypropylene particles in a mass ratio of 1:10 to 3:7 using a planetary mixer. The flame-retardant emulsion is obtained by dispersing and grinding water, a dispersant, aluminum hydroxide, and a polyacrylic acid emulsion, wherein the mass ratio of the dispersant, aluminum hydroxide, and polyacrylic acid is 1:5:5 to 1:7:3, the angle between the two opposite sides of the outer shell is 16°~18°, the outer shell is provided with microwave radiation heat dissipation holes, the inner core is arranged at the bottom of the outer shell, the inner core is an array formed by a plurality of regular tetrahedrons, and is assembled by a double-layer composite absorbing flame-retardant substrate formed by a flame-retardant paper-conductive layer, and the wave-transparent cap is arranged on the top of the outer shell.

2. The single cone light-weight high-power absorbing material according to claim 1, characterized in that: It comprises a metal bracket for hanging the wave-absorbing material, and the metal bracket is arranged at the bottom of the outer shell.

3. The single cone light-weight high-power absorbing material according to claim 1, characterized in that: The flame retardant performance of the flame retardant board meets the A1 standard, and after the conductive layer is coated on the surface of the flame retardant board, the surface resistance is 300-500 ohms / square.

4. The single-cone lightweight high-power absorbing material according to claim 1, characterized in that: After the surface of the flame retardant paper is coated with a conductive layer, the surface resistance is less than 300 ohms / square.

5. The single-cone lightweight high-power absorbing material according to claim 1, characterized in that: The flame retardant paper is made of asbestos fiber and has a thickness of 0.2-0.4 mm.

6. The single-cone lightweight high-power absorbing material according to claim 1, characterized in that: The material of the wave-transmitting cap is polypropylene.

7. A method for manufacturing a single-cone lightweight high-power absorbing material, characterized in that The method includes: (1) Manufacturing an absorbing material outer shell substrate assembly sheet; first, cutting a flame retardant board into triangular sheets, applying a layer of conductive liquid on the surface of the triangular sheets, drying, applying the same amount of conductive liquid on the other side of the triangular sheets, drying, the drying temperature is 50°C to 70°C, the drying time is 10 min to 15 min, the conductive film thickness is 0.1 mm to 0.2 mm, and forming an absorbing material outer shell substrate assembly sheet; (2) Manufacturing the inner core of the absorbing material; first, a layer of conductive liquid is applied on the surface of the asbestos fiber paper, and the paper is dried at a temperature of 50°C to 70°C for 10 to 15 minutes to form a composite substrate for the inner core of the absorbing material; the composite substrate is cut and assembled into a regular tetrahedron; and then a plurality of regular tetrahedrons are bonded into a pyramid array to form the inner core of the absorbing material; (3) Assembly of single-cone lightweight high-power absorbing materials; opening microwave radiation heat dissipation holes on the absorbing material outer shell substrate assembly pieces, bonding the absorbing material outer shell substrate assembly pieces with microwave radiation heat dissipation holes together to form a regular tetrahedral outer shell, bonding the inner core and the metal bracket together with fireproof adhesive, and then bonding the metal bracket to the bottom of the outer shell with fireproof adhesive, and finally placing the wave-transmitting cap on the top of the outer shell and bonding it with fireproof adhesive.

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