An ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure

Abstract

This invention belongs to the field of microwave absorption technology, and particularly relates to an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure, comprising: multiple unit cells, all fixed to a base plate, arranged in an array, each unit cell including a trunk fixed to the base plate with its axis perpendicular to the base plate; multiple thin plates coaxially fixed to the trunk, all parallel to the base plate, with equal distances between adjacent plates; and the size of the thin plates gradually decreasing from bottom to top. This ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure exhibits a minimum reflection loss of less than -9dB in the 2 to 18GHz frequency range, efficiently absorbing incident electromagnetic waves and reducing reflections, thereby improving the stealth effect of flight equipment. Manufactured using 3D printing technology, the fabrication process is more flexible and efficient, and the structure possesses higher mechanical strength and greater stability and reliability.

Description

Technical Field

[0001] This invention belongs to the field of microwave absorption technology, and particularly relates to an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure. Background Technology

[0002] The rapid popularization and widespread application of electronic communication technologies have greatly improved the convenience of daily life and industrial production. However, these advancements have also brought challenges such as electromagnetic interference (EMI) and electromagnetic pollution. These problems not only pose a threat to human health but also challenge the electromagnetic compatibility and interference immunity of electronic devices.

[0003] However, existing microwave absorption structures do not provide ideal microwave absorption. Therefore, an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure to solve the above-mentioned problems.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] An ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure includes: multiple unit cells, all fixed to a base plate, the multiple unit cells being arranged in an array, each unit cell including a trunk, the trunk being fixed to the base plate, the axis of the trunk being perpendicular to the base plate, multiple thin plates being coaxially fixed to the trunk, the multiple thin plates being parallel to the base plate, the distance between adjacent thin plates being equal, and the size of the multiple thin plates being gradually reduced from bottom to top.

[0007] In an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical load-bearing structure of the present invention, the base plate, the trunk and the sheet are made of the following materials: by mass fraction, 94% ABS powder, 5% polypyrrole nanotubes and 1% multi-walled carbon nanotubes.

[0008] In an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical load-bearing structure of the present invention, the cross-sectional shape of the thin sheet is a regular polygon or a circle.

[0009] In an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure of the present invention, the thickness t1 of the thin sheet is 0.2 to 1.0 mm.

[0010] In an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical load-bearing structure of the present invention, the main trunk is frustum-shaped, the bottom diameter D1 of the main trunk is 20-40mm, the top diameter of the main trunk is 11-25mm, and the height H2 of the main trunk is 6-8mm.

[0011] In an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure of the present invention, there are three thin sheets, the cross-sectional shape of the thin sheets is a regular quadrilateral, the length / width L2 of the thin sheet at the bottom is 20-40mm, the length / width L3 of the thin sheet in the middle is 20-38mm, the length / width L4 of the thin sheet at the top is 20-38mm, and the distance H3 between two adjacent thin sheets is 1.5-3.5mm.

[0012] A method for fabricating the aforementioned ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure comprises the following steps:

[0013] The materials are mixed and made into filaments. The model of the ultra-wideband bionic tree-shaped microwave absorbing-mechanical load-bearing structure optimized by the ant colony algorithm is imported into the 3D printing slicing software for slicing. The printing parameters are set, the printing code is generated, the printing code is input into the printer, the filaments are installed on the printer, the printer is adjusted, and then printing begins. After printing is completed, the ultra-wideband bionic tree-shaped microwave absorbing-mechanical load-bearing structure is post-processed, and the fabrication is completed.

[0014] Compared with the prior art, the present invention has the following advantages and technical effects:

[0015] The ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure of this invention has a minimum reflection loss of less than -9dB in the frequency range of 2 to 18GHz, which can efficiently absorb incident electromagnetic waves, reduce reflection, and thus improve the stealth effect of flight equipment. It is manufactured using 3D printing technology, which makes the preparation process more flexible and efficient, and has high mechanical strength, making the structure more stable and reliable. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0018] Figure 2 This is a reflection curve diagram of the present invention at different incident angles;

[0019] Figure 3 This is a schematic diagram of the three-point bend test of the present invention;

[0020] Figure 4 This is a flexural strength curve of the present invention;

[0021] Figure 5This is a reflectance curve diagram for different numbers of thin sheets in this invention;

[0022] Figure 6 This is a graph showing the reflectance of different sheet shapes according to the present invention;

[0023] Figure 7 This is a reflection curve diagram of the main trunk with different numbers of side edges in this invention;

[0024] Figure 8 This is a flowchart of the ant colony algorithm optimization process in this invention;

[0025] Among them, 1. base plate; 2. main trunk; 3. thin sheet. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Reference Figure 1 This invention discloses an ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure, comprising: multiple unit cells, all fixed to a base plate 1, the multiple unit cells being arranged in an array, each unit cell including a trunk 2, the trunk 2 being fixed to the base plate 1, the axis of the trunk 2 being perpendicular to the base plate 1, multiple thin plates 3 being coaxially fixed to the trunk 2, the multiple thin plates 3 being parallel to the base plate 1, the distance between two adjacent thin plates 3 being equal, and the size of the multiple thin plates 3 being gradually reduced from bottom to top.

[0029] In one feasible embodiment, the base plate 1, the main body 2, and the sheet 3 are made of materials comprising, by mass fraction, 94% ABS powder, 5% polypyrrole nanotubes, and 1% multi-walled carbon nanotubes.

[0030] In one feasible embodiment, the cross-sectional shape of the sheet 3 is a regular polygon or a circle.

[0031] In one feasible embodiment, the thickness t1 of the sheet 3 is 0.2 to 1.0 mm.

[0032] In one feasible embodiment, the main trunk 2 is frustum-shaped, with a bottom diameter D1 of 20-40 mm, a top diameter of 11-25 mm, and a height H2 of 6-8 mm.

[0033] Main trunk 2 can also be set as a frustum.

[0034] In one feasible embodiment, there are three thin sheets 3. The cross-sectional shape of the thin sheets 3 is a regular quadrilateral. The length / width L2 of the thin sheet 3 at the bottom is 20-40 mm, the length / width L3 of the thin sheet 3 in the middle is 20-38 mm, the length / width L4 of the thin sheet 3 at the top is 20-38 mm, and the distance H3 between two adjacent thin sheets 3 is 1.5-3.5 mm.

[0035] A method for fabricating an ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure, comprising the following steps:

[0036] The materials are mixed and made into filaments. The model of the ultra-wideband bionic tree-shaped microwave absorbing-mechanical load-bearing structure optimized by the ant colony algorithm is imported into the 3D printing slicing software for slicing. The printing parameters are set, the printing code is generated, the printing code is input into the printer, the filaments are installed on the printer, the printer is adjusted, and then printing begins. After printing is completed, the ultra-wideband bionic tree-shaped microwave absorbing-mechanical load-bearing structure is post-processed, and the fabrication is completed.

[0037] One specific example:

[0038] Reference Figure 1 The ultra-wideband biomimetic tree-shaped microwave absorption-mechanical support structure of the present invention includes a base plate 1, a plurality of main trunks 2 fixedly attached to the top surface of the base plate 1, the plurality of main trunks 2 being arrayed, and three thin plates 3 being fixedly attached sequentially from bottom to top on the main trunks 2, the three thin plates 3 being equally spaced, the thin plates 3 being coaxially arranged with the main trunks 2, the thickness of the thin plates 3 being t1 = 0.8 mm, the length / width L2 of the thin plate 3 located at the bottom being 40 mm, the length / width L3 of the thin plate 3 located in the middle being 38 mm, the length / width L4 of the thin plate 3 located at the top being 25 mm, the distance between two adjacent thin plates 3 being H3 = 3.5 mm, the thickness of the base plate 1 being H1 = 2 mm, the height of the main trunks 2 being H2 = 8 mm, the bottom diameter of the main trunks 2 being D1 = 36 mm, and the top diameter of the main trunks 2 being D2 = 12.5 mm.

[0039] Preparation method:

[0040] 94% ABS powder, 5% polypyrrole nanotubes, and 1% multi-walled carbon nanotubes by weight were simultaneously added to a mixer and mixed. The mixed material was then added to a twin-screw extruder in multiple batches to form filaments with a diameter of 1.70 to 1.80 mm. The ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure was optimized using an ant colony algorithm. The optimized ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure model was imported into 3D printing slicing software for slicing. The printer speed was set to 100 mm / s, and the nozzle diameter was 0.6 mm. After slicing, G-code was generated. The generated G-code was then substituted into a desktop FDM 3D printer. The prepared filaments were pre-cut to the length of the 3D printer, and the printer was leveled. The heated bed temperature of the 3D printer was set to 50°C, and the cooling fan was turned on. After preheating, printing began. After printing, the resulting semi-finished product was placed in an environment of 50–60°C for heat treatment to relieve stress, thus obtaining the ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure.

[0041] In this application, the mixture of ABS powder, polypyrrole nanotubes, and multi-walled carbon nanotubes forms a composite material with high dielectric loss, which can effectively convert electromagnetic wave energy into heat energy, thereby achieving electromagnetic wave absorption. The addition of polypyrrole nanotubes and multi-walled carbon nanotubes enhances the conductivity of the material, forming a spatially continuous conductive network, which further promotes the dissipation of electromagnetic waves.

[0042] The composite filaments prepared by the twin-screw extruder have their diameter precisely controlled, ensuring the consistency and uniformity of the filaments. The consistency and uniformity of the filaments are crucial for the accuracy and performance of the structure in the subsequent 3D printing process, because the uniformity of the filaments directly affects the mechanical properties and electromagnetic characteristics of the printed biomimetic tree structure.

[0043] 3D printing technology allows for precise control of printing parameters, such as printing speed and nozzle diameter, thereby optimizing the density and porosity of the structure. The density and porosity of the structure directly affect the propagation and absorption of electromagnetic waves inside the material, which is crucial for adjusting the wave absorption performance of the material.

[0044] Reference Figure 7 This application utilizes an ant colony algorithm to optimize the mechanical bearing-microwave absorption structure model, ensuring that the structure meets mechanical performance requirements while also having the best wave absorption effect. The biomimetic tree-like spatial multi-layer structure facilitates the deep penetration and multiple reflections of electromagnetic waves, thereby improving absorption efficiency.

[0045] Heat treatment after printing helps release the stress generated during the printing process and helps to further optimize the internal structure of the material, thereby improving its microwave absorption performance and ensuring the long-term stability and performance of the material.

[0046] The reflectivity and three-point bending of the ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure were tested to evaluate its microwave absorption performance and mechanical load-bearing capacity. (Refer to...) Figure 2-7 Therefore, it can be seen that the solution in this embodiment is one of the better solutions.

[0047] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0048] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An extremely wideband biomimetic tree-shaped microwave absorption-mechanical load bearing structure, characterized in that, include: Multiple unit cells are fixedly attached to the base plate (1). The multiple unit cells are arranged in an array. Each unit cell includes a main stem (2). The main stem (2) is fixedly attached to the base plate (1). The axis of the main stem (2) is perpendicular to the base plate (1). Multiple thin plates (3) are coaxially fixed to the main stem (2). The multiple thin plates (3) are parallel to the base plate (1). The distance between two adjacent thin plates (3) is equal. The size of the multiple thin plates (3) is gradually reduced from bottom to top. The base plate (1), the main trunk (2) and the sheet (3) are made of the following materials: by mass fraction, 94% ABS powder, 5% polypyrrole nanotubes and 1% multi-walled carbon nanotubes. The cross-sectional shape of the thin sheet (3) is a regular polygon or a circle; The thickness t1 of the thin sheet (3) is 0.2~1.0 mm; The main trunk (2) is frustum-shaped, the bottom diameter D1 of the main trunk (2) is 20~40mm, the top diameter of the main trunk (2) is 11~25mm, and the height H2 of the main trunk (2) is 6~8mm; The number of the thin slices (3) is three, the cross-sectional shape of the thin slices (3) is a regular quadrilateral, the length / width L2 of the thin slice (3) at the bottom is 20~40mm, the length / width L3 of the thin slice (3) in the middle is 20~38mm, the length / width L4 of the thin slice (3) at the top is 20~38mm, and the distance H3 between two adjacent thin slices (3) is 1.5~3.5mm; ABS powder, polypyrrole nanotubes, and multi-walled carbon nanotubes are mixed to form a composite material with high dielectric loss, which converts electromagnetic wave energy into heat energy and realizes electromagnetic wave absorption. The addition of polypyrrole nanotubes and multi-walled carbon nanotubes enhances the conductivity of the material and forms a spatially continuous conductive network, which promotes the dissipation of electromagnetic waves.

2. A method for fabricating the ultra-wideband biomimetic tree-shaped microwave absorbing-mechanical load-bearing structure as described in claim 1, characterized in that, The steps are as follows: The materials are mixed and made into filaments. The model of the ultra-wideband bionic tree-shaped microwave absorbing-mechanical load-bearing structure optimized by the ant colony algorithm is imported into the 3D printing slicing software for slicing. The printing parameters are set, the printing code is generated, the printing code is input into the printer, the filaments are installed on the printer, the printer is adjusted, and then printing begins. After printing is completed, the ultra-wideband bionic tree-shaped microwave absorbing-mechanical load-bearing structure is post-processed, and the fabrication is completed.

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