A wave-absorbing yarn and wave-absorbing fabric

Abstract

The application belongs to the field of fabric treatment, and particularly relates to a wave-absorbing yarn and a wave-absorbing fabric. In order to solve the technical problem that the wave-absorbing performance of a composite fiber fabric in the prior art is poor because, after electromagnetic waves enter the composite fiber fabric, the part of the electromagnetic waves that enters the wave-absorbing fiber after being reflected is less, and the part of the electromagnetic waves that reaches the outside after being reflected is more, the application provides a wave-absorbing yarn. The wave-absorbing yarn comprises a wave-transparent base body, a connecting surface is formed on a part of the circumferential surface of the wave-transparent base body in the circumferential direction, the cross section of the connecting surface is parabolic, a reflecting structure is connected to the connecting surface, the reflecting structure has a reflecting surface that is consistent with the connecting surface, and a wave-absorbing body is arranged in the wave-transparent base body and located at the focal point of the reflecting surface. The application further provides a wave-absorbing fabric comprising the wave-absorbing yarn. The parabolic reflecting surface can effectively reflect the electromagnetic waves to the wave-absorbing body, thereby improving the wave-absorbing capacity of the wave-absorbing yarn and the wave-absorbing fabric.

Description

Technical Field

[0001] This invention belongs to the field of fabric treatment, and in particular relates to a wave-absorbing yarn and a wave-absorbing fabric. Background Technology

[0002] In existing technologies, microwave absorbing fabrics are generally classified into coated microwave absorbing fabrics and structural matrix microwave absorbing fabrics.

[0003] Coated microwave absorbing fabrics can be obtained by coating the interior or surface of a three-dimensional fabric with a microwave absorbing agent (such as carbon black, graphite, or ferrite, which are resistive or magnetic dielectric materials). In this case, the fabric serves as a stable support structure, while the microwave absorbing agent absorbs electromagnetic waves.

[0004] Structural matrix-type radar-absorbing fabrics can be produced by directly weaving yarns or fibers with radar-absorbing properties (such as nickel-iron fibers or carbon fibers) into a three-dimensional fabric product, and then experimentally testing the radar-absorbing performance and influence parameters of the woven three-dimensional fabric. For example, Chinese invention patent CN113183548B, authorized on March 24, 2023, discloses a cone array type radar stealth textile material and its preparation method. The cone array type radar stealth textile material includes at least one layer of composite fiber fabric, which is made by blending 15-25% flame-retardant polyester filament, 15-25% polyester staple fiber, 8-15% heat-set fiber, 1-30% spiral stainless steel fiber, and 1-30% nickel-plated carbon fiber (i.e., radar-absorbing fiber).

[0005] After electromagnetic waves enter the composite fiber fabric, the path of the electromagnetic waves is as follows:

[0006] (1) It directly reaches the absorbing fiber and is absorbed by the absorbing fiber;

[0007] (2) It passes through the wave-transmitting fiber to reach the wave-absorbing fiber and is absorbed by the wave-absorbing fiber;

[0008] (3) After entering the composite fiber fabric, it is reflected and enters the microwave absorbing fiber;

[0009] (4) After entering the composite fiber fabric, it reaches the outside world through reflection.

[0010] In the aforementioned composite fiber fabric, the electromagnetic waves are reflected and enter the absorbing fibers in a relatively small amount, while a relatively large amount reaches the outside world, resulting in poor wave absorption performance of the composite fiber fabric. Summary of the Invention

[0011] The purpose of this invention is to provide a microwave-absorbing yarn and microwave-absorbing fabric to solve the technical problem that when electromagnetic waves are injected into the composite fiber fabric of the prior art, a small portion of the electromagnetic waves enters the microwave-absorbing fibers after reflection, while a large portion reaches the outside after reflection, resulting in poor microwave absorption performance of the composite fiber fabric.

[0012] To achieve the above objectives, the technical solution for the wave-absorbing yarn provided by this invention is as follows:

[0013] A microwave-absorbing yarn includes a microwave-transparent substrate, a portion of the outer circumferential surface of the microwave-transparent substrate being a connecting surface, the cross-section of the connecting surface being parabolic, a reflective structure being connected to the connecting surface, the reflective structure having a reflective surface that matches the connecting surface, and a microwave-absorbing body located at the focal point of the reflective surface within the microwave-transparent substrate.

[0014] Furthermore, on the cross-section of the absorbing yarn, the line connecting the two ends of the reflective surface along the circumference of the transparent substrate passes through the focal point of the reflective surface.

[0015] Furthermore, the absorber is cylindrical, and on the cross-section of the absorber yarn, the center of the absorber coincides with the focal point of the reflecting surface.

[0016] Furthermore, the radius of the absorber must satisfy the following condition: the radius of the absorber is not less than the wavelength of the electromagnetic wave to be absorbed.

[0017] Furthermore, the reflective structure is a parabolic reflective layer.

[0018] Furthermore, the cross-section of the wave-transparent substrate is a symmetrical structure with the line connecting the two ends of the reflecting surface along the circumference of the wave-transparent substrate as the axis of symmetry.

[0019] The beneficial effects of the microwave-absorbing yarn of the present invention are as follows: The present invention is a pioneering invention. The microwave-transparent substrate can support the reflective structure and the microwave absorber; a parabolic connecting surface is provided on a part of the outer peripheral surface of the microwave-transparent substrate, and the reflective structure can be easily connected through the connecting surface. Since the reflective surface of the reflective structure matches the connecting surface, the reflective surface is also parabolic, thereby reflecting the electromagnetic waves passing through the microwave-transparent substrate into the microwave absorber located at the focal point of the reflective surface. This increases the proportion of electromagnetic waves entering the microwave absorber after reflection and reduces the proportion of electromagnetic waves reaching the outside after reflection, thus improving the microwave absorption performance of the microwave-absorbing yarn.

[0020] To achieve the above objectives, the technical solution for the wave-absorbing fabric provided by this invention is as follows:

[0021] A microwave-absorbing fabric is woven from microwave-absorbing yarn. The microwave-absorbing yarn includes a microwave-transparent matrix. A portion of the outer circumferential surface of the microwave-transparent matrix is ​​a connecting surface with a parabolic cross-section. A reflective structure with a reflective surface that is completely in contact with the connecting surface is connected to the connecting surface. A microwave-absorbing body is provided in the microwave-transparent matrix at the focal point of the reflective surface. All reflective surfaces are located on the same side of the microwave-absorbing fabric.

[0022] Furthermore, on the cross-section of the absorbing yarn, the line connecting the two ends of the reflective surface along the circumference of the transparent substrate passes through the focal point of the reflective surface.

[0023] Furthermore, the absorber is cylindrical, and on the cross-section of the absorber yarn, the center of the absorber coincides with the focal point of the reflecting surface.

[0024] Furthermore, the radius of the absorber must satisfy the following condition: the radius of the absorber is not less than the wavelength of the electromagnetic wave to be absorbed.

[0025] Furthermore, the reflective structure is a parabolic reflective layer.

[0026] Furthermore, the wave-transparent substrate is a symmetrical structure with the line connecting the two ends of the reflective surface along the circumference of the wave-transparent substrate as the axis of symmetry.

[0027] Furthermore, the wave-absorbing fabric is a plain weave fabric.

[0028] The beneficial effects of the microwave-absorbing fabric of the present invention are as follows: The present invention is a pioneering invention. The microwave-transparent substrate can support the reflective structure and the microwave absorber; a parabolic connecting surface is provided on a part of the outer peripheral surface of the microwave-transparent substrate, and the reflective structure can be easily connected through the connecting surface. Since the reflective surface of the reflective structure matches the connecting surface, the reflective surface is also parabolic, thereby reflecting the electromagnetic waves passing through the microwave-transparent substrate into the microwave absorber located at the focal point of the reflective surface, increasing the proportion of electromagnetic waves entering the microwave absorber after reflection, reducing the proportion of electromagnetic waves incident from the side of the microwave-absorbing fabric away from the reflective surface that return to the outside after reflection, and improving the microwave absorption performance of the microwave-absorbing yarn. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the parabolic reflection principle in existing technology;

[0030] Figure 2 This is a schematic diagram of the structure of an embodiment of the wave-absorbing yarn in this invention;

[0031] Figure 3 This is a schematic diagram of the structure of an embodiment of the wave-absorbing fabric in this invention;

[0032] Figure 4 for Figure 3 Enlarged view of the structure of section A;

[0033] Figure 5 A comparison chart of the absorption capabilities of sample a and sample b;

[0034] Figure 6 This is a comparison chart of the absorption capabilities of samples a and c.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Transparent substrate; 2. Absorber; 3. Reflective layer; 4. Focal point; 6. Concave mirror. Detailed Implementation

[0037] To address the technical problem that when electromagnetic waves are incident on existing composite fiber fabrics, a small portion of the electromagnetic waves enters the absorbing fibers after reflection, while a larger portion reaches the outside, resulting in poor wave absorption performance of the composite fiber fabrics, the main concept of this invention is to reflect as many electromagnetic waves as possible onto the absorbing body through a parabolic reflective surface, thereby improving the wave absorption capability of the absorbing yarn and the absorbing fabric.

[0038] The cross-section in this invention is defined as follows: the cross-section of an existing cylinder is circular, and based on this, the cross-section of the connecting surface is parabolic.

[0039] The parabolic shape in this invention is defined as follows: Figure 1 As shown, in the prior art, the concave mirror 6 can focus the incident light to the focal point of the concave mirror 6, and the curve obtained by the intersection of the plane containing the incident light and the plane containing the outgoing light with the mirror surface of the concave mirror 6 is parabolic in shape.

[0040] Since light is essentially an electromagnetic wave, the concave mirror 6 can focus electromagnetic waves to the focal point of the concave mirror 6.

[0041] The present invention will be further described in detail below with reference to the embodiments.

[0042] Specific embodiments of the wave-absorbing yarn provided by this invention:

[0043] like Figure 2 As shown, the microwave-absorbing yarn includes a microwave-transparent substrate 1. A portion of the outer circumferential surface of the microwave-transparent substrate 1 is a connecting surface, and the cross-section of the connecting surface is parabolic. A reflective structure is connected to the connecting surface, and the reflective structure has a reflective surface that matches the connecting surface. An absorber 2 is located at the focal point 4 of the reflective surface within the microwave-transparent substrate 1. Specifically, the microwave-transparent substrate 1 is made of existing microwave-transparent materials such as microwave-transparent polyvinyl chloride, as long as the microwave-transparent substrate 1 has sufficient strength to support the three-dimensional structure of the microwave-absorbing yarn. The absorber 2 is made of existing microwave-absorbing materials such as galvanized iron wire and nickel-plated carbon fiber. The reflective structure is made of existing materials such as metals that can reflect electromagnetic waves.

[0044] The wave-transparent substrate 1 can support the reflective structure and the wave-absorbing body 2. A parabolic connecting surface is provided on a part of the outer peripheral surface of the wave-transparent substrate 1, and the reflective structure can be easily connected through the connecting surface. Since the reflective surface of the reflective structure matches the connecting surface, the reflective surface is also parabolic, thereby reflecting the electromagnetic waves passing through the wave-transparent substrate 1 into the wave-absorbing body 2 located at the focal point 4 of the reflective surface. This increases the proportion of electromagnetic waves entering the wave-absorbing body 2 after reflection and reduces the proportion of electromagnetic waves reaching the outside after reflection, thereby improving the wave-absorbing performance of the wave-absorbing yarn.

[0045] To further improve the wave-absorbing performance of wave-absorbing yarn, as a specific implementation method, such as Figure 2 As shown, in the cross-section of the absorbing yarn, the line connecting the two ends of the reflective surface along the circumference of the transparent substrate 1 passes through the focal point 4 of the reflective surface. Of course, in other embodiments, the circumferential length of the reflective surface can be reduced. Making the line connecting the two ends of the reflective surface along the circumference of the transparent substrate 1 pass through the focal point 4 of the reflective surface ensures that the maximum amount of electromagnetic waves incident on the reflective surface are reflected into the absorber 2, thus improving the absorption performance of the absorbing yarn.

[0046] It should be noted that, compared to the technical solution where the line connecting the two ends of the reflective surface along the circumference of the wave-transparent substrate 1 passes through the focal point 4 of the reflective surface, if the circumferential length of the reflective surface is increased, then the "reflective surface" includes the original part and the added part. The original part is the true reflective surface, meaning the line connecting the two ends of the true reflective surface along the circumference of the wave-transparent substrate 1 passes through the focal point 4 of the reflective surface. The added part cannot focus electromagnetic waves to the focal point 4; therefore, the added part is a false "reflective surface" different from the true reflective surface. However, this technical solution still falls within the protection scope of this application. In this case, a portion of the outer circumferential surface of the wave-transparent substrate 1 is a parabolic curved surface. This curved surface has a connecting surface for connecting the true reflective surface and a connecting portion for connecting the false "reflective surface." That is, the connecting surface is only a part of the parabolic curved surface, not all parabolic curved surfaces constitute the connecting surface.

[0047] To further improve the wave-absorbing performance of wave-absorbing yarn, as a specific implementation method, such as Figure 2 As shown, the absorber 2 is cylindrical. On the cross-section of the absorbing yarn, the center of the absorber 2 coincides with the focal point 4 of the reflecting surface. This ensures that electromagnetic waves reflected from all points on the reflecting surface and passing through the focal point 4 can all pass through the absorber 2 of the same length, avoiding situations where some electromagnetic waves reflected by the reflecting surface and passing through the focal point 4 are absorbed to a lesser extent, thus improving the absorption performance of the absorbing yarn. Of course, in other specific embodiments, the absorber 2 can also be a cuboid or other shape.

[0048] To further improve the wave-absorbing performance of wave-absorbing yarn, as a specific implementation method, such as Figure 2 As shown, the radius of the absorber 2 satisfies the following condition: the radius of the absorber 2 is not less than the wavelength of the electromagnetic wave to be absorbed. Specifically, the radius of the absorber 2 is greater than the wavelength of the electromagnetic wave to be absorbed. However, in other specific embodiments, the diameter of the absorber 2 can also be greater than the wavelength of the electromagnetic wave to be absorbed, that is, the radius of the absorber 2 is greater than half the wavelength of the electromagnetic wave to be absorbed; or, the radius of the absorber 2 is equal to the wavelength of the electromagnetic wave to be absorbed. Since the electromagnetic wave directly incident and passing through the focal point 4 will be absorbed by the portion of the absorber 2 away from the reflecting surface, and the electromagnetic wave reflected by the reflecting surface and passing through the focal point 4 will be absorbed by the portion of the absorber 2 towards the reflecting surface, when the radius of the absorber 2 is not less than the wavelength of the electromagnetic wave to be absorbed, it can effectively absorb the electromagnetic waves directly incident on the absorber 2 and the electromagnetic waves reflected by the reflecting surface to the absorber 2, thereby improving the absorption performance of the absorber yarn.

[0049] To simplify the structure, in one specific embodiment, the reflective structure is a parabolic reflective layer 3. Specifically, the reflective layer 3 is coated on the connecting surface, resulting in a simple structure. However, in other embodiments, the reflective structure may also include a rectangular substrate, on which material is removed to form a parabolic reflective surface.

[0050] To facilitate the processing of the reflective layer 3, in one specific embodiment, the cross-section of the wave-transparent substrate 1 is a symmetrical structure with the line connecting the two ends of the reflective surface along the circumference of the wave-transparent substrate 1 as the axis of symmetry. This eliminates the need to distinguish the front and back of the absorbing yarns during the processing of the reflective layer 3, simplifying the process. However, in other specific embodiments, the outer periphery of the wave-transparent substrate 1 is composed of parabolas and semicircles on its cross-section. In this embodiment, the specific structure of the wave-transparent substrate 1 is not limited, as long as it has a connecting surface.

[0051] Specific embodiments of the wave-absorbing fabric provided by the present invention:

[0052] like Figure 2-4 As shown, the microwave-absorbing fabric in this embodiment is woven from microwave-absorbing yarn, and the reflective surfaces are all located on the same side of the microwave-absorbing fabric. The specific structure of the microwave-absorbing yarn is the same as that in the specific embodiment of the microwave-absorbing yarn in this invention, and will not be described again here.

[0053] Specifically, the wave-absorbing fabric is a plain weave fabric, but in other specific embodiments, the wave-absorbing fabric can also be woven using other existing weaving methods, such as twill fabric.

[0054] Experiments were conducted using the rectangular waveguide method:

[0055] Sample a: Plain weave fabric with a reflective surface;

[0056] Sample b: Plain weave fabric without a reflective surface, forming a control group with sample a that is identical in structure except for the reflective surface;

[0057] Sample c: A fabric with a reflective surface but made of side-by-side absorbent yarns, forming a control group with the same structure as sample a except for the weaving method;

[0058] like Figure 5 and 6 As shown, reflectivity reflects the wave absorption capability. The smaller the reflectivity (with a negative sign for comparison), the more electromagnetic waves are absorbed, which means that the sample has a better wave absorption capability.

[0059] like Figure 5 As shown, sample b's maximum absorption performance is only around -2dB, with an insignificant absorption effect. However, with the addition of a reflective surface, sample a's maximum absorption performance is around -9dB, demonstrating a significant absorption effect. Furthermore, within the 1-10GHz electromagnetic band, sample a's absorption performance remains stable around -8dB, indicating that sample a has a better absorption capability for electromagnetic waves in the 1-10GHz frequency range. This proves that a reflective surface can effectively improve the absorption capability of absorbing yarns and fabrics. Within the 10-18GHz electromagnetic band, sample a exhibits multiple absorption valleys. This is because the electromagnetic parameters of sample a change significantly with frequency, leading to multiple absorption valleys. Nevertheless, it is still evident that sample a, with its reflective surface, has a better absorption capability than sample b, which lacks a reflective surface.

[0060] like Figure 6 As shown, sample c exhibits relatively stable absorption capability in the 1-5 GHz electromagnetic wave band, poor absorption capability in the 5-10 GHz electromagnetic wave band, and multiple absorption valleys in the 10-18 GHz electromagnetic wave band. Comparing the absorption capability curves of sample a and sample c, it can be seen that the plain weave structure can improve the fabric's absorption capability for electromagnetic waves in the 5-10 GHz frequency range, and the valley value of the absorption capability curve of sample a is lower, indicating that the plain weave structure can improve the maximum absorption capability of the fabric.

[0061] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wave-absorbing yarn, characterized by, The wave-absorbing yarn comprises a wave-transparent base, a connecting surface of which is in a part of the circumference direction, the cross section of the connecting surface is parabolic, a reflecting structure is connected to the connecting surface, the reflecting structure has a parabolic reflecting surface which is consistent with the connecting surface, and a wave-absorbing body is arranged in the wave-transparent base at the focal point of the reflecting surface.

2. The wave-absorbing yarn of claim 1, wherein, In the cross section of the wave-absorbing yarn, the reflecting surface passes through the focal point of the reflecting surface along the line connecting the two ends of the circumference direction of the wave-transparent base.

3. The wave-absorbing yarn according to claim 1 or 2, wherein The wave-absorbing body is cylindrical, and in the cross section of the wave-absorbing yarn, the center of the wave-absorbing body coincides with the focal point of the reflecting surface.

4. The wave-absorbing yarn of claim 3, wherein, The radius of the wave-absorbing body satisfies: the radius of the wave-absorbing body is not less than the wavelength of the electromagnetic wave to be absorbed.

5. The wave-absorbing yarn according to claim 1 or 2, wherein The reflecting structure is a parabolic reflecting layer.

6. The wave-absorbing yarn of claim 2, wherein, The cross section of the wave-transparent base is a symmetrical structure with the line connecting the two ends of the circumference direction of the wave-transparent base as the symmetrical axis.

7. A wave-absorbing fabric, characterized by, The wave-absorbing fabric is woven by the wave-absorbing yarn of any one of claims 1-6, and the reflecting surfaces are all located on the same side of the wave-absorbing fabric.

8. The wave-absorbing fabric according to claim 7, wherein, The wave-absorbing fabric is a plain fabric.

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