A method for patterning deposition of a single-layer wave-absorbing frequency selective surface of a composite material
Patent Information
- Application Number
- CN202610864180.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-06-15
- Publication Date
- 2026-09-29
AI Technical Summary
[0004]本发明的目的在于克服现有吸波频率选择表面制备工艺复杂、结构层数较多、与复合材料基体结合强度不足以及难以实现高精度图案化金属沉积等问题，提供一种复合材料单层吸波频率选择表面的图案化沉积方法
[0021](1)采用激光图案化处理与选择性化学镀相结合的方式，实现复合材料表面的图案化金属沉积，无需传统蚀刻工艺即可获得高精度金属图案；
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Figure CN122833595A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of surface metallization and electromagnetic functional structure preparation technology of composite materials, specifically relating to a patterned deposition method for a single-layer frequency-selective absorbing surface of a composite material. Background Technology
[0002] Fiber-reinforced resin matrix composites are widely used in aerospace, radomes, electronic communications, and defense equipment due to their lightweight, high specific strength, good corrosion resistance, and excellent dielectric properties. With the increasing complexity of the electromagnetic environment, higher demands are placed on the electromagnetic shielding, electromagnetic compatibility, and stealth performance of composite material structures. Therefore, constructing frequency selective surfaces (FSS) on composite material surfaces that combine structural load-bearing and electromagnetic control functions has become an important research direction. Existing frequency selective surfaces typically use processes such as copper foil etching, screen printing, and vacuum deposition to prepare conductive patterns. Although these processes can achieve transmission or reflection control in specific frequency bands, they generally suffer from problems such as complex processes, high costs, insufficient bonding strength with the composite matrix, and difficulty in adapting to complex curved surface structures. Meanwhile, existing absorbing frequency selective surfaces often employ multilayer or sandwich structures composed of resistive layers, dielectric layers, and metal layers, resulting in large thickness, high weight, and complex manufacturing processes, which are detrimental to the development of lightweight electromagnetic functional structures.
[0003] In recent years, laser surface treatment technology has been widely used in the functionalization of polymer-based composite materials due to its advantages such as non-contact processing, high processing precision, and controllable patterns. Combined with chemical plating and electroplating processes, patterned metal deposition can be achieved on composite material surfaces, providing a new technical approach for the preparation of frequency-selective surfaces. By forming a conductive metal layer in a predetermined region, not only can the interfacial bonding between the metal layer and the substrate be improved, but it is also beneficial to construct periodic metal structures with specific electromagnetic response characteristics. However, existing technologies still have shortcomings in terms of patterned deposition precision, metal layer continuity, interfacial bonding strength, and the construction of monolayer absorbing frequency-selective surfaces. Therefore, there is an urgent need to develop a patterned deposition method for monolayer absorbing frequency-selective surfaces of composite materials to achieve high-precision patterned metal deposition and construct monolayer absorbing frequency-selective surfaces with both good structural stability and electromagnetic absorption performance. Summary of the Invention
[0004] The purpose of this invention is to overcome the problems of complex fabrication processes, numerous structural layers, insufficient bonding strength with composite material matrices, and difficulty in achieving high-precision patterned metal deposition in existing microwave absorbing frequency-selective surfaces. This invention provides a patterned deposition method for a single-layer microwave absorbing frequency-selective surface on a composite material. This method utilizes a process route combining laser patterning, selective chemical plating, and electroplating thickening to achieve high-precision patterned metal deposition on the surface of the composite material, thus constructing a single-layer frequency-selective surface with microwave absorbing capabilities.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A method for patterning deposition of a single-layer composite material absorbing frequency-selective surface includes the following steps:
[0007] S1. Pre-treat the composite matrix to remove surface oil, dust and other impurities;
[0008] S2. A preset grid pattern is formed on the surface of the composite material using laser scanning, which improves the surface roughness and surface activity of the patterned area;
[0009] S3. The laser-treated specimen is placed in anhydrous ethanol for ultrasonic cleaning to remove debris, carbonized residues and loose adhering substances generated during laser processing; then the specimen is dried using a drying device.
[0010] S4. Place the specimen in the sensitizing solution for sensitization treatment, so that the surface adsorbs the sensitizing components; after sensitization, rinse the surface of the specimen with deionized water to remove residual sensitizing solution.
[0011] S5. Place the sensitized specimen in the activation solution for activation treatment to form catalytic active sites in the patterned area; after activation, rinse the surface of the specimen with deionized water to remove residual activation solution.
[0012] S6. Place the activated specimen in a chemical copper plating solution for selective chemical plating. The copper layer is preferentially deposited in the patterned area to form a continuous conductive copper layer. After chemical plating, rinse with deionized water and dry.
[0013] S7. Electroplating thickening treatment is performed using a chemically plated copper layer as a conductive substrate to obtain a continuous and dense patterned copper layer; after electroplating, the layer is rinsed with deionized water and dried.
[0014] S8. A single-layer periodic metal mesh structure is formed on the surface of the composite material to construct a single-layer frequency-selective absorbing surface.
[0015] Preferably, the composite matrix is a glass fiber reinforced resin matrix composite.
[0016] Preferably, the ultrasonic cleaning uses anhydrous ethanol as the cleaning medium, the ultrasonic cleaning temperature is 20-50℃, the ultrasonic power density is 10-20W / L, the ultrasonic frequency is 20-60kHz, and the ultrasonic cleaning time is 3-10min.
[0017] Preferably, the drying process is carried out by hot air drying, with a drying temperature of 40-60°C and a drying time of 5-20 minutes.
[0018] Preferably, the patterned metal layer is a periodic square grid structure with a period of 8 to 12 mm and a line width of 1 to 3 mm.
[0019] Preferably, the laser patterning process employs a pulsed laser scanning method with a laser power of 4–20W, a scanning speed of 1000–2000 mm / s, and a laser frequency of 20–40 kHz.
[0020] Compared with the prior art, the present invention has the following beneficial effects:
[0021] (1) By combining laser patterning with selective chemical plating, patterned metal deposition on the surface of composite materials can be achieved without the need for traditional etching processes to obtain high-precision metal patterns.
[0022] (2) Laser treatment can improve the surface activity and surface roughness of the patterned area, providing favorable conditions for subsequent metal deposition and enhancing the interfacial bonding ability between the metal layer and the substrate.
[0023] (3) A continuous and dense patterned copper layer is obtained through the synergistic effect of chemical plating and electroplating, which improves conductivity and structural stability;
[0024] (4) The frequency selective surface is made of a single-layer periodic metal mesh structure, which has the advantages of simple structure, light weight and simplified manufacturing process compared with traditional multi-layer or sandwich absorbing structures.
[0025] (5) The constructed single-layer frequency selective absorbing surface has obvious frequency selective absorption characteristics in the target frequency band, which can realize electromagnetic shielding performance with absorption loss as the main factor, and improve the electromagnetic protection capability of composite materials. Attached Figure Description
[0026] Figure 1 Schematic diagram of surface patterning deposition process for selecting absorption frequency of single layer composite material
[0027] Figure 2 A schematic diagram illustrating the selection of surface mesh structure size and patterned deposition for single-layer absorption frequency. a represents the mesh structure size, and b represents the actual deposition result.
[0028] Figure 3This is an optical micrograph of the laser-patterned region and the patterned copper layer. a is the original substrate, and b1-b3 are the laser-treated surface, the electroless plated surface, and the electroplated surface, respectively.
[0029] Figure 4 The images show the scanning electron microscope (SEM) images and Cu elemental distribution maps of the electroless and electroplated patterned copper layers. a1-c1 represent the SEM morphology of the electroless plated parts at 1000, 2000, and 5000x magnification, and d1-e1 represent the Cu elemental distribution of the electroless plated parts at 1000x magnification. a2-c2 represent the SEM morphology of the electroplated parts at 1000, 2000, and 5000x magnification, and d2-e2 represent the Cu elemental distribution of the electroplated parts at 1000x magnification.
[0030] Figure 5 This diagram illustrates the effect of patterned deposition processes on the three-dimensional morphology of the surface. 'ac' represents the results after laser treatment, electroless plating, and electroplating, respectively.
[0031] Figure 6 Electromagnetic response curves of patterned deposited single-layer grid copper-plated specimens Detailed Implementation
[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to the following embodiments.
[0033] Example
[0034] A method for patterning deposition of a single-layer composite material absorbing frequency-selective surface includes the following steps:
[0035] (1) Matrix pretreatment
[0036] Glass fiber reinforced epoxy resin composite material (GFRP) with dimensions of 100mm×100mm×2mm was selected as the matrix material. First, the surface of the specimen was cleaned with anhydrous ethanol to remove oil and impurities, and then allowed to air dry for later use.
[0037] (2) Laser patterning
[0038] A pulsed fiber laser was used to pattern the GFRP surface. The laser power was 12W, the laser frequency was 20kHz, and the scanning speed was 1500mm / s. Figure 2 (a) shows a preset grid pattern that selectively processes the surface of the specimen, so that the patterned area forms an activated surface with high surface activity and deposition capacity.
[0039] (3) Ultrasonic cleaning and drying
[0040] The laser-treated specimens were immersed in anhydrous ethanol and ultrasonically cleaned for 5 minutes at 40°C, 15 W / L, and 40 kHz to remove laser-processed debris, carbonized residues, and loose adhering substances. The specimens were then dried in a 60°C forced-air drying oven for 5 minutes.
[0041] (4) Sensitization treatment
[0042] The specimens were immersed in a sensitizing solution for 5 minutes for sensitization. The sensitizing solution was prepared from SnCl2·2H2O and HCl, with SnCl2·2H2O concentration of 2 g / L and HCl concentration of 50 g / L. After sensitization, the specimen surface was rinsed with deionized water to remove residual sensitizing solution.
[0043] (5) Activation treatment
[0044] The sensitized specimens were immersed in an activation solution for 5 minutes to activate them, thereby forming catalytically active sites in the patterned areas. The activation solution was prepared from PdCl₂·2H₂O and HCl, with PdCl₂·2H₂O concentration of 0.2 g / L and HCl concentration of 50 g / L. After activation, the specimen surface was rinsed with deionized water to remove residual activation solution.
[0045] (6) Selective electroless copper plating
[0046] The activated specimen was immersed in a chemical copper plating solution for 3 hours. Due to the high surface activity and catalytic ability of the patterned area, the copper layer preferentially deposited in the patterned area, forming a continuous conductive copper layer. After chemical plating, the specimen was rinsed with deionized water and dried. The chemical copper plating solution was prepared from CuSO4·5H2O, HCHO, KNaC4H4O6·4H2O, and H2SO4, with CuSO4·5H2O concentration of 10 g / L, HCHO concentration of 5 g / L, KNaC4H4O6·4H2O concentration of 30 g / L, and H2SO4 concentration of 0.5 g / L. Due to the high surface activity and catalytic ability of the laser-patterned area, the copper layer preferentially deposited in the patterned area, forming a continuous conductive copper layer. After chemical plating, the specimen was rinsed with deionized water and dried.
[0047] (7) Electroplating thickening
[0048] Using a chemically plated copper layer as the conductive layer, the specimen was placed in an electroplating solution for 3 hours. The electroplating solution was prepared from CuSO4·5H2O and H2SO4, with a CuSO4·5H2O concentration of 220 g / L and an H2SO4 concentration of 70 g / L. After electroplating, the specimen was rinsed with deionized water and dried to obtain a continuous and dense patterned copper plating layer.
[0049] (8) Forming a single-layer frequency-selective absorbing surface
[0050] A single-layer periodic metal mesh structure is formed on the surface of a composite material using a patterned deposition process. The mesh period is 10 mm and the line width is 2 mm, forming a single-layer frequency-selective absorbing surface.
[0051] like Figure 2 As shown in (b), after patterned deposition, the copper layer is deposited only in the pre-defined patterned area, achieving patterned copper deposition on the surface of the composite material. Further, as... Figure 3 As shown in the optical microscope, the coating surface formed under 12W laser power is uniform and continuous, with no obvious defects, indicating that this process can obtain a high-quality metal deposition layer; Figure 4 As shown in the electron microscope images, both electroless and electroplated layers exhibit continuous and dense structures at different magnifications. The Cu element distribution results indicate that copper is uniformly distributed throughout the plating area, further verifying the integrity and uniformity of the formed copper layer. Figure 5 Three-dimensional morphology analysis shows that laser patterning and subsequent coating processes create a distinct three-dimensional micro-undulating structure on the composite material surface. This increases the surface roughness parameter Sa, improving the average roughness, while simultaneously decreasing Sz, indicating a reduction in extreme peak-to-valley differences and a more uniform surface morphology. In summary... Figures 3 to 5 It can be seen that the copper coating prepared by the present invention has good continuity, density and uniformity, and can form a stable bond with the composite matrix.
[0052] like Figure 6 As shown, the prepared single-layer frequency-selective absorbing surface exhibits significant frequency-selective absorption characteristics in the 2–18 GHz frequency band, forming absorption peaks at approximately 8.1 GHz and 11.5 GHz, respectively. The total shielding effectiveness reaches 14.5 dB at 8.1 GHz and 10.2 dB at 11.5 GHz. In contrast, the total shielding effectiveness of untreated glass fiber reinforced resin matrix composites in the 2–18 GHz frequency band is typically below 3 dB, indicating virtually no effective electromagnetic shielding capability. Therefore, the single-layer metal mesh structure constructed in this invention significantly improves the electromagnetic shielding performance of the composite material in the target frequency band. Furthermore, the absorption loss of this structure is significantly higher than the reflection loss throughout the entire test frequency band, indicating that its electromagnetic shielding mechanism is primarily absorption-based. The single-layer metal mesh structure constructed through laser patterning, selective chemical plating, and electroplating achieves effective absorption and modulation of electromagnetic waves, exhibiting excellent frequency-selective absorption characteristics.
[0053] It should be noted that the above embodiments are only preferred embodiments of the present invention. Any adjustments or equivalent substitutions made by those skilled in the art to parameters such as laser power, laser frequency, scanning speed, ultrasonic cleaning conditions, sensitization activation time, chemical plating time, electroplating time, and mesh structure size without departing from the technical concept of the present invention shall fall within the protection scope of the present invention.
Claims
1. A method for patterned deposition of a single-layer frequency-selective absorbing surface of a composite material, characterized in that, Includes the following steps: S1. Pre-treat the composite matrix to remove surface oil, dust and other impurities; S2. A preset grid pattern is formed on the surface of the composite material using laser scanning, which improves the surface roughness and surface activity of the patterned area; S3. Place the laser-treated specimen in anhydrous ethanol for ultrasonic cleaning to remove debris, carbonized residues and loose adhering substances generated during laser processing; then perform drying treatment. S4. Sensitize and activate the specimen to form catalytic active sites in the patterned area; S5. Place the activated specimen in a chemical copper plating solution for selective chemical plating, so that the copper layer is preferentially deposited in the patterned area to form a continuous conductive copper layer. S6. Electroplating thickening treatment is performed using a chemically plated copper layer as a conductive substrate to obtain a continuous and dense patterned copper layer. S7. A single-layer periodic metal mesh structure is formed on the surface of the composite material to construct a single-layer frequency-selective absorbing surface.
2. The patterned deposition method according to claim 1, characterized in that, The composite matrix is a fiber-reinforced resin-based composite material.
3. The patterned deposition method according to claim 2, characterized in that, The fiber-reinforced resin matrix composite material is one or more of glass fiber-reinforced resin matrix composite material, carbon fiber-reinforced resin matrix composite material, and aramid fiber-reinforced resin matrix composite material.
4. The patterned deposition method according to claim 1, characterized in that, The laser scanning uses pulsed laser to form a preset grid pattern, with a laser power of 4-20W, a laser frequency of 20-40kHz, and a scanning speed of 1000-2000mm / s.
5. The patterned deposition method according to claim 1, characterized in that, The ultrasonic cleaning uses anhydrous ethanol as the cleaning medium, with an ultrasonic cleaning temperature of 20–50°C, an ultrasonic power density of 10–20 W / L, and an ultrasonic frequency of 20–60 kHz. z The ultrasonic cleaning time is 3 to 10 minutes.
6. The patterned deposition method according to claim 1, characterized in that, The sensitizing solution contains SnCl2·2H2O and HCl, wherein the concentration of SnCl2·2H2O is 1–4 g / L and the concentration of HCl is 40–60 g / L; the activating solution contains PdCl2·2H2O and HCl, wherein the concentration of PdCl2·2H2O is 0.1–0.4 g / L and the concentration of HCl is 40–60 g / L.
7. The patterned deposition method according to claim 1, characterized in that, The electroless copper plating is used to form an initial conductive layer in the patterned area. The electroless copper plating solution contains CuSO4·5H2O, HCHO, KNaC4H4O6·4H2O and H2SO4, wherein the concentration of CuSO4·5H2O is 5-20 g / L, the concentration of HCHO is 2-10 g / L, the concentration of KNaC4H4O6·4H2O is 20-50 g / L, and the concentration of H2SO4 is 0.1-2 g / L.
8. The patterned deposition method according to claim 1, characterized in that, The electroplating is used to thicken the initial conductive layer to obtain a continuous and dense patterned copper layer. The electroplating solution contains CuSO4·5H2O and H2SO4, wherein the concentration of CuSO4·5H2O is 150-300 g / L and the concentration of H2SO4 is 40-100 g / L.
9. The patterned deposition method according to claim 1, characterized in that, The single-layer absorbing frequency selection surface is a single-layer periodic metal mesh structure with a mesh period of 8-12 mm and a line width of 1-3 mm.