3D printing high-performance terahertz wave absorber and manufacturing method

Abstract

The invention relates to the technical field of terahertz wave electromagnetic interference shielding, in particular to a 3D printing high-performance terahertz wave absorber and a manufacturing method thereof.The manufacturing method comprises the steps that a space coordinate system is established in modeling software, an initial cuboid structure is established, and an included angle is formed between the edge of the initial cuboid structure and the coordinate axis of the space coordinate system; hollow structures in the X-axis direction, the Y-axis direction and the Z-axis direction of the space coordinate system are determined correspondingly, the hollow structures in the X-axis direction, the Y-axis direction and the Z-axis direction of the space coordinate system act on the initial cuboid structure, and a 3D printing model is obtained; printing the 3D printing model to obtain a 3D printing structure; the 3D printing structure is treated through a graphene dip-coating method, so that the surface of the 3D printing structure has conductivity, and finally the terahertz wave absorber is formed; according to the invention, high absorptivity and high absorption bandwidth can be realized at the same time, and the terahertz wave absorber can be flexibly prepared.

Description

Technical Field

[0001] The present invention relates to the technical field of terahertz wave electromagnetic interference shielding, and in particular to a 3D printed high-performance terahertz absorber and a manufacturing method thereof. Background Art

[0002] With the continuous development of terahertz technology, terahertz-based devices are gradually entering the application market, including communications equipment, imaging security inspection, and various experimental equipment. When these devices are operating, a large amount of terahertz electromagnetic interference is generated, which puts new requirements on shielding against terahertz electromagnetic interference in space.

[0003] Currently, there are three main types of terahertz wave absorbing materials: metamaterials based on micro- and nanostructures primarily achieve this through structural absorption, but suffer from issues such as narrow bandwidth and susceptibility to external factors; carbon-based absorbing materials rely on the inherent properties of the material for absorption, but face limitations such as poor surface dispersion and strong interface reflection. Emerging porous two-dimensional conductive materials, while showing good performance in terms of both absorptivity and bandwidth, still face challenges such as complex preparation processes, susceptibility to oxidation, and difficulty in large-scale production. Therefore, the development of materials with broadband, easy-to-process, and efficient absorbing properties remains a major challenge in current terahertz wave absorption research.

[0004] In recent years, 3D printing technology, thanks to its simple preparation and ease of processing, has been increasingly applied to the development of terahertz absorbers. For example, Li Shennan's team at Xi'an Jiaotong University achieved near-perfect single-band absorption at 0.94 THz through projection microscopic imaging and electron-beam evaporation gold deposition. Zhang Liuyang's team, using microscale 3D printing and a stack of multilayer ring resonators, achieved absorption exceeding 90% in the 1.07-2.88 THz frequency band.

[0005] While research on terahertz absorbers based on 3D printing has made some progress, existing results still leave room for improvement in terms of absorption performance and bandwidth. Maintaining the flexible processing advantages of 3D printing while further improving absorption performance and expanding the absorption bandwidth has become a key area of research and development in terahertz absorber technology that urgently needs breakthroughs. Summary of the Invention

[0006] In view of the above problems, the present invention provides a 3D printed high-performance terahertz absorber and a manufacturing method, which solves the technical problem in terahertz absorbing technology of the lack of a terahertz absorber design method that can simultaneously have high absorptivity and wide absorption bandwidth and can be flexibly prepared.

[0007] In one aspect, the present invention provides a 3D-printed high-performance terahertz absorber, characterized in that the 3D-printed high-performance terahertz absorber includes a cube grid composed of a plurality of mutually parallel strip structures along a first direction, a plurality of mutually parallel strip structures along a second direction, and a plurality of mutually parallel strip structures along a third direction, wherein the cube grid includes a plurality of interconnected cube cavities; the first direction, the second direction, and the third direction are perpendicular to each other;

[0008] The spacing between the plurality of mutually parallel strip structures along the first direction, the spacing between the plurality of mutually parallel strip structures along the second direction, and the spacing between the plurality of mutually parallel strip structures along the third direction are all equal to a preset spacing a; the width of all the strip structures is equal to a preset width b, and the surfaces of all the strip structures are coated with graphene;

[0009] The outer envelope of the cube grid is in the shape of a flat plate, the flat surface of the flat plate is the absorbing surface, and the angle between the first direction and the absorbing surface is The angle between the second direction and the absorbing surface is The third direction is parallel to the absorbing surface.

[0010] In one aspect, the present invention provides a method for manufacturing a 3D-printed high-performance terahertz absorber, comprising the following steps:

[0011] Step S1: establishing a spatial coordinate system in a modeling software, and establishing an initial cuboid structure in the spatial coordinate system, wherein the sides of the initial cuboid structure have angles with the coordinate axes of the spatial coordinate system;

[0012] Step S2: respectively determining hollow structures along the X-axis, Y-axis, and Z-axis directions of the spatial coordinate system, and applying the hollow structures along the X-axis, Y-axis, and Z-axis directions of the spatial coordinate system to the initial rectangular parallelepiped structure to obtain a 3D printing model;

[0013] Step S3: Printing the 3D printing model using a 3D printer to obtain a 3D printed structure;

[0014] Step S4: treating the 3D printed structure with a graphene dip coating method to make the surface of the 3D printed structure conductive, thereby finally forming a terahertz absorber.

[0015] Preferably, the step S1 specifically includes:

[0016] Step S1-1, establishing a spatial coordinate system formed by mutually perpendicular X-axis, Y-axis and Z-axis in the modeling software;

[0017] Step S1-2: In the spatial coordinate system, a first cuboid with dimensions of 1 cm × 1 cm × 0.5 cm is created, with the length, width, and height of the cuboid parallel to the X-axis, Y-axis, and Z-axis, respectively. The first cuboid is rotated around the Y-axis by an angle of The initial rectangular parallelepiped structure T1 is obtained.

[0018] Preferably, the step S2 specifically includes:

[0019] Step S2-1: Create a first basic cuboid with dimensions of a × a × 1.2 cm along the X-axis, with the long side of the first basic cuboid parallel to the X-axis. Use the first basic cuboid as a basic unit, and form a first cuboid array with b as the interval around each unit. Perform a Boolean subtraction operation on the initial cuboid structure T1 and the first cuboid array to obtain structure T2.

[0020] Step S2-2: Build a second basic cuboid with dimensions of a × a × 1 cm along the Y-axis, with the long side of the second basic cuboid parallel to the Y-axis. Use the second basic cuboid as a basic unit and form a second cuboid array with b as the interval around each unit. Perform a Boolean subtraction operation on the structure T2 and the second cuboid array to obtain a structure T3.

[0021] Step S2-3: Build a third basic cuboid with dimensions of a × a × 0.7 cm along the Z-axis, with the long side of the second basic cuboid parallel to the Z-axis. Use the third basic cuboid as a basic unit, and form a third cuboid array with b as the interval around each unit. Perform a Boolean subtraction operation on the structure T3 and the third cuboid array to obtain a structure T4.

[0022] Step S2-4: Rotate the structure T4 as a whole with the Y axis as the rotation axis by an angle - The 3D printing model is obtained.

[0023] Preferably, in steps S1-2 and S2-4, the parameters The value of is 22.5°; in steps S2-1, S2-1 and S2-1, the value of parameter a is 500μm, and the value of parameter b is 150μm.

[0024] Preferably, the 3D printer is a P400 UHD; the printing accuracy of the 3D printer is 32.5 μm; and the printing material is a rigid resin material.

[0025] Preferably, the step S4 specifically includes:

[0026] The 3D printed structure is immersed in a graphene dispersion for two minutes. After the immersion is completed, the structure is taken out and placed in a suitable environment for drying to make the surface of the structure conductive, thereby finally forming a terahertz absorber.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects:

[0028] (1) The present invention fully considers the wavelength range of the 0.5-2.0 THz frequency band and reasonably sets the aperture size between 300-500 μm to adapt it to the target terahertz wave frequency band, thereby reducing the reflection of the terahertz wave at the interface. However, the cumbersome etching or template technology of traditional manufacturing processes cannot achieve precise aperture size control and adjustment. The present invention uses 3D printing technology to accurately set the aperture size through digital modeling, thereby greatly improving the feasibility and accuracy of material preparation and achieving precise control of the aperture size to meet the requirements of matching surface impedance with air impedance.

[0029] (2) The present invention fully utilizes the characteristic of constant thinnest thickness during 3D printing. Traditional circular through holes are difficult to print and are prone to collapse due to local excessive thinness. The present invention adopts a square aperture design, so that the thinnest thickness of the entire structure is not less than the printing accuracy limit of the equipment, avoiding the collapse caused by excessive thinness during the printing process, improving the stability and success rate of 3D printing manufacturing, and enabling the porous absorbing structure to be smoothly prepared and formed.

[0030] (3) In terms of structural design, the present invention sets a specific rotation angle, which is combined with the hollow array to make the hole distribution of adjacent layers appear dislocated. When the terahertz wave is incident, a continuously reflecting propagation path will be formed inside, resulting in multiple internal reflections, which improves the propagation capability, strengthens the absorption of terahertz wave energy, and improves the performance of the terahertz absorber. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings are only for purposes of illustrating particular embodiments and are not to be considered limiting of the invention.

[0032] Figure 1 This is a structural diagram of the 3D printed high-performance terahertz absorber provided by the present invention.

[0033] Figure 2 This is a flow chart of the 3D printed high-performance terahertz absorber manufacturing method provided by the present invention.

[0034] Figure 3 Schematic diagram of the hollowing process of the 3D printed high-performance terahertz absorber model provided by the present invention.

[0035] Figure 4 This is an optical microscope image of the 3D printed structure provided by the present invention.

[0036] Figure 5 This is an optical microscope image of the surface of the 3D printed structure provided by the present invention after being dip-coated with graphene.

[0037] Figure 6 The wave absorbing efficiency corresponding to the wave absorber with different incident angles provided by the present invention. DETAILED DESCRIPTION

[0038] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. In addition, the present invention can also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited by the specific embodiments disclosed below.

[0039] Terahertz instruments and equipment are subject to electromagnetic interference, particularly in high-sensitivity terahertz communication systems and precision imaging equipment. External electromagnetic noise can cause signal distortion and increase bit error rates, severely impacting the system's communication quality and detection accuracy. Compared to traditional absorbers, 3D-printed absorbers offer advantages in processing cost, flexibility, and mass production. Compared to existing 3D-printed terahertz absorber technology, the design, combining a porous structure with a dip-coated graphene surface, offers the advantages of both high absorption efficiency and bandwidth.

[0040] The high-performance terahertz absorber designed in this invention can reduce undesirable radiation and suppress the impact of electromagnetic interference on equipment. Its porous skeleton structure allows for multiple internal reflections of terahertz waves. Graphene dip-coating on the structure's surface allows for internal conversion of electromagnetic energy into heat. 3D printing allows for flexible fabrication. The result is a high-performance terahertz absorber that can be 3D-printed in the 0.5-2.0 THz frequency range, achieving an absorption efficiency of at least 99%.

[0041] The technical solution provided by this invention uses 3D printing technology to fabricate porous absorbing structures, achieving high absorptivity and broadband absorption of terahertz waves. Based on research findings on absorbing materials, the present invention determined that porous materials must meet three key requirements: surface impedance matching with air impedance, internal multiple reflection propagation capability, and internal conductivity. Furthermore, considering the practical feasibility of 3D printing, the present invention proposes the additional requirement of controllable structural dimensions (for regular structures). These four requirements serve as the basis for the fabrication of 3D-printed porous terahertz absorbers.

[0042] (1) Surface impedance and air impedance matching conditions

[0043] Principle: The matching of surface impedance and air impedance has a significant impact on absorbing performance. In the absorber structure, the difference in relative impedance between the material and air directly determines the strength of the reflected signal. When the impedances are mismatched, the reflection effect is more pronounced. However, when the absorber surface impedance matches the air impedance, reflections are effectively reduced.

[0044] Technical implementation plan: When using 3D printing technology to prepare porous absorbing structures, the pore size of the porous material is reasonably formed according to the wavelength range corresponding to the target terahertz wave frequency band, and the material thickness is ensured to be adapted to it, so as to meet the condition of matching the surface impedance with the air impedance and effectively reduce the reflected signal.

[0045] (2) Internal multiple reflection propagation capability conditions

[0046] Principle Explanation: The ability to propagate electromagnetic waves with multiple reflections is another key factor in ensuring a material's absorption effectiveness. When the aperture size meets the aforementioned matching conditions, terahertz waves can enter the material. However, if the material lacks sufficient internal reflection restraint mechanisms, the terahertz waves will pass directly through the pores and penetrate the material, preventing effective absorption. Therefore, a corresponding structure must be constructed within the material to restrict the linear propagation of terahertz waves, promoting multiple reflections and thereby enhancing energy absorption.

[0047] Technical implementation: In terms of the internal structure of the absorber, a processing method combining rotation angle and hollow array is adopted, so that the hole distribution of adjacent layers is staggered. When the terahertz wave is incident, a continuously reflected propagation path will be formed inside, meeting the condition of internal multiple reflection propagation capability and enhancing the absorption of terahertz wave energy.

[0048] (3) The structure has conductive conditions inside

[0049] Principle: The material's conductivity (metallicity) plays a crucial role in terahertz wave absorption. The absorption of terahertz waves by porous materials essentially converts electromagnetic energy into heat. When a terahertz wave enters the material and undergoes multiple reflections, due to the material's internal conductivity, each reflection converts a portion of the electromagnetic energy into heat, ultimately causing the terahertz wave to completely attenuate. Conversely, if the material is an insulator, the reflected electromagnetic energy cannot be converted, resulting in the wave's transmission.

[0050] Technical implementation method: By conducting conductive treatment on the surface of the structure, that is, dipping graphene into the surface, the surface is able to convert electromagnetic energy into thermal energy, thereby achieving effective absorption of terahertz wave energy.

[0051] (4) Conditions for controllable structural dimensions (regular structure)

[0052] Principle Explanation: Considering the practical feasibility of 3D printing, the precision of existing 3D printing equipment is limited to a certain extent, with a minimum precision of approximately 30μm. The optimal aperture size corresponding to the 0.5-2.0THz frequency band is generally between 300-500μm. Furthermore, when printing irregular structures, while it is easy to meet the requirements of multiple internal reflections, ensuring that the minimum thickness of the entire structure reaches 30μm is a major challenge, because areas that are too thin are prone to local collapse during the printing process. Therefore, in order to successfully produce porous absorbing structures through 3D printing, it is necessary to effectively control the structural dimensions to form a regular structure.

[0053] Technical implementation: There are two methods for structural design: irregular and regular. During the design stage of the porous absorbing structure, by designing a regular structure, the size of the structure is reasonably planned according to the precision parameters of the 3D printing equipment to avoid printing failures caused by unreasonable size. This ensures that the entire structure can be successfully manufactured through 3D printing and meets the condition of controllable structural size, thereby ensuring the successful preparation of porous terahertz absorbers based on 3D printing.

[0054] In order to illustrate the effectiveness of the method proposed in the present invention, the above technical solution of the present invention is described in detail below through a specific embodiment.

[0055] The present invention discloses a 3D printed high performance terahertz absorber, such as Figure 1 As shown, the 3D printed high-performance terahertz absorber includes a cube grid composed of a plurality of mutually parallel strip structures along a first direction, a plurality of mutually parallel strip structures along a second direction, and a plurality of mutually parallel strip structures along a third direction, wherein the cube grid includes a plurality of interconnected cube cavities; the first direction, the second direction, and the third direction are perpendicular to each other;

[0056] The spacing between the plurality of mutually parallel strip structures along the first direction, the spacing between the plurality of mutually parallel strip structures along the second direction, and the spacing between the plurality of mutually parallel strip structures along the third direction are all equal to a preset spacing a; the width of all the strip structures is equal to a preset width b, and the surfaces of all the strip structures are coated with graphene;

[0057] The outer envelope of the cube grid is in the shape of a flat plate, the flat surface of the flat plate is the absorbing surface, and the angle between the first direction and the absorbing surface is The angle between the second direction and the absorbing surface is The third direction is parallel to the absorbing surface.

[0058] In some embodiments, the parameter The value of is 22.5°; the value of parameter a is 500μm, and the value of parameter b is 150μm.

[0059] like Figure 2 As shown, the present invention discloses a method for manufacturing a 3D printed high-performance terahertz absorber, and the specific implementation steps are as follows:

[0060] Step S1: establishing a spatial coordinate system in modeling software, and establishing an initial rectangular parallelepiped structure in the spatial coordinate system, wherein the sides of the initial rectangular parallelepiped structure have angles with the coordinate axes of the spatial coordinate system.

[0061] The present invention uses modeling software such as C4D or SolidWorks to establish an initial rectangular parallelepiped structure. Specifically, a spatial coordinate system is first established, and the spatial coordinate system includes an X-axis, a Y-axis, and a Z-axis that are perpendicular to each other.

[0062] In the spatial coordinate system, a first cuboid with dimensions of 1 cm × 1 cm × 0.5 cm was constructed, with the length, width, and height of the first cuboid parallel to the X-axis, Y-axis, and Z-axis, respectively. The first cuboid was then rotated 22.5° about the Y-axis to obtain the initial cuboid structure, which was labeled T1.

[0063] The initial rectangular parallelepiped structure formed in this step serves as the foundation for the subsequent construction of complex hollow structures. By rotating the rectangular parallelepiped by a specific angle about the Y-axis, this step can create misalignment between the different layers of the subsequent hollow structure, enhancing the multiple reflection effect and thus improving the terahertz absorption performance.

[0064] Step S2: respectively determine the hollow structures along the X-axis, Y-axis, and Z-axis directions of the spatial coordinate system, and apply the hollow structures along the X-axis, Y-axis, and Z-axis directions of the spatial coordinate system to the initial rectangular parallelepiped structure to obtain a 3D printing model.

[0065] like Figure 3 As shown, the present invention establishes a hollow structure along the X-axis, Y-axis and Z-axis directions of the spatial coordinate system, and the specific steps include:

[0066] (1) X-axis structure construction

[0067] Along the X-axis, a cuboid with dimensions of 500μm×500μm×1.2cm is established, ensuring that its long side remains parallel to the X-axis. Next, using this cuboid as the basic unit, a first cuboid array is formed with a spacing of 150μm in the top, bottom, left, and right directions. Afterwards, a subtraction Boolean operation is used to operate the previously marked initial cuboid structure T1 with the first cuboid array. Through this operation, a structure with a 500μm hollowed-out spacing in the X-direction can be obtained, which is recorded as T2. This structure initially forms a specific hollowed-out shape in the X-axis direction, which is conducive to the subsequent realization of multi-path reflection performance.

[0068] (2) Y-axis structure construction

[0069] Along the Y-axis, a rectangular parallelepiped with dimensions of 500μm × 500μm × 1cm was constructed, with its long side parallel to the Y-axis. Similarly, using this rectangular parallelepiped as a unit, a second rectangular parallelepiped array was formed, with spacing of 150μm in both the top, bottom, left, and right directions. Then, using the subtraction Boolean operation again, T2 was applied to the second rectangular parallelepiped array, resulting in a structure with 500μm hollowing out in both the X and Y directions, which was recorded as T3. This structure further expanded the hollowing out range and increased the possibility of multipath reflection of terahertz waves inside.

[0070] (4) Z-axis structure construction

[0071] Along the Z-axis, a rectangular parallelepiped measuring 500μm × 500μm × 0.7cm was designed, ensuring its long side was parallel to the Z-axis. Using this rectangular parallelepiped as a unit, a third rectangular parallelepiped array was formed, with 150μm spacing between the top, bottom, left, and right edges. A Boolean subtraction operation was then performed on T3 from the third rectangular parallelepiped array, resulting in a structure with 500μm hollowing out in the X, Y, and Z directions, designated T4. Finally, T4 was rotated -22.5° around the Y-axis, resulting in a 3D printable model.

[0072] Through the above steps, the present invention can form a porous absorbing structure. The aperture width of the porous absorbing structure is 500 μm, the spacing between the apertures is 150 μm, and the aperture size can match the wavelength range corresponding to the target frequency band of the terahertz wave, which can effectively reduce reflection and improve the absorbing performance.

[0073] On the other hand, the present invention rotates a rectangular parallelepiped with each side parallel to the coordinate axis by 22.5° with the Y-axis as the rotation axis to obtain an initial rectangular parallelepiped structure. By combining the rotation angle with the hollow array, the aperture distribution of adjacent layers is dislocated, thereby forming a continuously reflecting propagation path, satisfying the condition of internal multiple reflection propagation capability, and enhancing the absorption of terahertz wave energy.

[0074] Step S3: Print the 3D printing model using a 3D printer to obtain a 3D printed structure.

[0075] The present invention may use a P400 UHD model 3D printer, the minimum printing accuracy of which is 32.5 μm.

[0076] In some embodiments, the printing material of the present invention may be a rigid resin material.

[0077] During the printing process, parameters such as temperature, print speed, and material flow rate need to be monitored and adjusted in real time to ensure a smooth printing process and avoid issues such as material blockage and poor interlayer adhesion. After printing is complete, the 3D printed structure is removed and inspected for surface quality, dimensional accuracy, and overall integrity to prepare for subsequent processing steps.

[0078] Figure 4 An optical microscope image showing the 3D-printed structure.

[0079] Step S4: treating the 3D printed structure with a graphene dip coating method to make the surface of the 3D printed structure conductive, thereby finally forming a terahertz absorber.

[0080] After 3D printing, a graphene dip coating method was used to make the surface of the 3D printed structure conductive. The specific steps are: immerse the printed structure in a graphene dispersion for two minutes, remove the structure after immersion, and place it in a suitable environment for drying to make the surface conductive, ultimately forming a terahertz absorber. Figure 5 An optical microscope image of the surface of a 3D printed structure dipped in graphene is shown.

[0081] In the above method, since the absorber structure is conductive, the terahertz wave converts electromagnetic energy into thermal energy when entering the material, causing the terahertz wave energy to completely attenuate. Figure 6 The corresponding absorption efficiency of the absorber at different incident angles is shown.

[0082] Although the specific embodiments of the present invention depict various actions or steps in a specific order, this should be understood as requiring such actions or steps to be performed in the specific order shown or in a sequential order, or requiring that all illustrated actions or steps should be performed to obtain the desired results. Under certain circumstances, multitasking and parallel processing may be advantageous. Similarly, although a number of specific implementation details are included in the above discussion, these should not be interpreted as limiting the scope of this disclosure. Certain features described in the context of separate embodiments can also be implemented in combination in a single implementation. Conversely, the various features described in the context of a single implementation can also be implemented in multiple implementations individually or in any suitable sub-combination. The above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or replacements that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered within the scope of protection of the present invention.

[0083] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A 3D printed high-performance terahertz absorber, characterized in that: The 3D printed high-performance terahertz absorber includes a cube grid composed of a plurality of parallel strip structures along a first direction, a second direction, and a third direction, wherein the cube grid has a plurality of interconnected cube cavities; the first direction, the second direction, and the third direction are perpendicular to each other; The spacing between the plurality of mutually parallel strip structures along the first direction, the second direction, and the third direction is equal to the preset spacing a; the width of all the strip structures is equal to the preset width b, and the surfaces of all the strip structures are coated with graphene; The outer envelope of the cube grid is in the shape of a flat plate, and the flat plate has an absorbing surface. The angle between the first direction and the absorbing surface is The angle between the second direction and the absorbing surface is The third direction is parallel to the absorbing surface.

2. A method for manufacturing a 3D printed high-performance terahertz absorber according to claim 1, characterized in that: The following steps are involved: Step S1: establishing a spatial coordinate system in a modeling software, and establishing an initial cuboid structure in the spatial coordinate system, wherein the sides of the initial cuboid structure have angles with the coordinate axes of the spatial coordinate system; Step S2: respectively determining hollow structures along the X-axis, Y-axis, and Z-axis directions of the spatial coordinate system, and applying the hollow structures along the X-axis, Y-axis, and Z-axis directions of the spatial coordinate system to the initial rectangular parallelepiped structure to obtain a 3D printing model; Step S3: Printing the 3D printing model using a 3D printer to obtain a 3D printed structure; Step S4: treating the 3D printed structure with a graphene dip coating method to make the surface of the 3D printed structure conductive, thereby finally forming a terahertz absorber.

3. The method for manufacturing a 3D printed high-performance terahertz absorber according to claim 2, wherein: The step S1 specifically includes: Step S1-1, establishing a spatial coordinate system formed by mutually perpendicular X-axis, Y-axis and Z-axis in the modeling software; Step S1-2: In the spatial coordinate system, a first cuboid with dimensions of 1 cm × 1 cm × 0.5 cm is created, with the length, width, and height of the cuboid parallel to the X-axis, Y-axis, and Z-axis, respectively. The first cuboid is rotated around the Y-axis by an angle of The initial rectangular parallelepiped structure T1 is obtained.

4. The method for manufacturing a 3D printed high-performance terahertz absorber according to claim 3, wherein: The step S2 specifically includes: Step S2-1: Create a first basic cuboid with dimensions of a × a × 1.2 cm along the X-axis, with the long side of the first basic cuboid parallel to the X-axis. Use the first basic cuboid as a basic unit, and form a first cuboid array with b as the interval around each unit. Perform a Boolean subtraction operation on the initial cuboid structure T1 and the first cuboid array to obtain structure T2. Step S2-2: Build a second basic cuboid with dimensions of a × a × 1 cm along the Y-axis, with the long side of the second basic cuboid parallel to the Y-axis. Use the second basic cuboid as a basic unit and form a second cuboid array with b as the interval around each unit. Perform a Boolean subtraction operation on the structure T2 and the second cuboid array to obtain a structure T3. Step S2-3: Build a third basic cuboid with dimensions of a × a × 0.7 cm along the Z-axis, with the long side of the second basic cuboid parallel to the Z-axis. Use the third basic cuboid as a basic unit, and form a third cuboid array with b as the interval around each unit. Perform a Boolean subtraction operation on the structure T3 and the third cuboid array to obtain a structure T4. Step S2-4: Rotate the structure T4 as a whole with the Y axis as the rotation axis by an angle The 3D printing model is obtained.

5. The method for manufacturing a 3D printed high-performance terahertz absorber according to claim 4, characterized in that: In the steps S1-2 and S2-4, the parameters The value of is 22.5°; in steps S2-1, S2-1 and S2-1, the value of parameter a is 500μm, and the value of parameter b is 150μm.

6. The method for manufacturing a 3D printed high-performance terahertz absorber according to claim 5, characterized in that: In the step S3: The 3D printer is a P400 UHD; the printing accuracy of the 3D printer is 32.5 μm; and the printing material is a rigid resin material.

7. The method for manufacturing a 3D printed high-performance terahertz absorber according to claim 6, wherein: The step S4 specifically includes: The 3D printed structure is immersed in a graphene dispersion for two minutes. After the immersion is completed, the structure is taken out and placed in a suitable environment for drying to make the surface of the structure conductive, thereby finally forming a terahertz absorber.

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