Method for treating carbon fiber weaving texture and dynamic gloss on surface of strip-shaped aluminum product

Abstract

The invention discloses a method for treating carbon fiber woven texture and dynamic gloss on the surface of a strip-shaped aluminum product, and aims to solve the problems that an existing water transfer printing and film pasting process is single in texture, poor in adhesive force and incapable of cooperating with the texture and the dynamic gloss. The method comprises the steps of profile extrusion pretreatment, precise cutting and end face shaping, self-adaptive grinding and polishing, directional degreasing and cleaning, texture-micro-nano structure cooperative laser, gradient anodic oxidation, texture strengthening and optical activation, dynamic gloss layer customized preparation, transparent protective layer integrated coating and segmented curing and shaping. Precise coupling of the carbon fiber texture and the dynamic gloss is achieved by extruding and preforming basic textures, cooperating with laser to construct a texture and micro-nano structure and directionally depositing a gloss layer, and meanwhile the durability is improved through gradient oxidation and a protective coating. The obtained product has the three-dimensional woven texture and dynamic gloss flowing along with the visual angle, the requirements of the high-end field are met, and the process is suitable for industrial continuous production.

Description

Technical Field

[0001] This invention belongs to the field of aluminum product surface treatment technology, and particularly relates to a method for treating the carbon fiber woven texture and dynamic gloss on the surface of long aluminum products. Background Technology

[0002] In the high-end consumer electronics, sporting goods, and automotive industries, carbon fiber materials, with their high strength, lightweight properties, and unique woven aesthetics, have become a core element for enhancing product added value. To achieve the carbon fiber appearance on aluminum substrates, which are cheaper and easier to process, existing technologies generally employ water transfer printing or the application of carbon fiber textured films. However, these methods have insurmountable drawbacks: firstly, the texture rendering is poor, the patterns are monotonous and rigid, only simulating the planar visual form of carbon fiber, failing to reproduce its three-dimensional woven texture, and the seams are visible, giving it a plastic feel, lacking the metallic three-dimensionality that aluminum substrates should possess, resulting in a significant difference in texture from real carbon fiber; secondly, adhesion and wear resistance are insufficient, the bonding force between the water transfer printing layer or the applied layer and the aluminum substrate is weak, and it is prone to wear and peeling due to friction, sweat, or cleaning agents during daily use, making it difficult to meet the long-term use requirements of products.

[0003] Meanwhile, existing processes face unique challenges in surface treatment of long aluminum products (such as electronic device frames and automotive trim strips): the elongated structure leads to poor texture continuity and uneven distribution of micro-nano structures in traditional laser processing, making it difficult to precisely control the film thickness during subsequent anodizing, further exacerbating defects such as blurred texture and disordered gloss. Furthermore, current technologies cannot effectively integrate carbon fiber woven textures with dynamic gloss, resulting in a monotonous visual appeal that fails to meet the high-end market's demand for personalized and differentiated appearances. Therefore, innovative processing methods that can balance texture realism, dynamic gloss effects, and process stability are urgently needed. Summary of the Invention

[0004] The purpose of this invention is to provide a method for treating the surface of long aluminum products with carbon fiber woven texture and dynamic gloss, so as to solve the problems mentioned in the background art.

[0005] In view of this, the present invention provides a method for treating the surface of long aluminum products with carbon fiber woven texture and dynamic gloss, comprising the following steps: Step 1: Profile extrusion pretreatment. The aluminum substrate is extruded into a long aluminum profile through a customized extrusion die with built-in textured preformed protrusions. The textured preformed protrusions are distributed along the inner wall of the die cavity according to the warp and weft direction of the carbon fiber weaving texture. Through the extrusion process, the aluminum substrate and the protrusions are squeezed and matched, so that the surface of the profile forms a shallow basic texture that is the same as the subsequent target texture. Step 2: Precise cutting and end face shaping. The long aluminum profile is cut into workpieces of the target length using a cutting device with vision positioning. At the same time, the end face of the workpiece is chamfered by a CNC grinding head. Step 3: Adaptive grinding and polishing. Using grinding equipment with pressure feedback and surface contour recognition functions, first, coarse grinding is used to remove extrusion defects on the profile surface, then fine grinding is used to clarify the micro-morphology of the basic texture, and finally, a flexible polishing head is used for mirror polishing. Step 4: Targeted degreasing and cleaning. First, use an alkaline degreasing agent to spray the surface of the workpiece for degreasing. Then, use an ultrasonic cleaning system to target and clean the basic textures and grooves on the surface of the workpiece. Finally, rinse with deionized water and dry. Step 5: Texture-micro / nano structure synergistic laser engraving. Using a computer-controlled femtosecond laser device, a carbon fiber-like woven texture is formed in the basic texture area on the workpiece surface. At the same time, a micro / nano optical structure adapted to the texture direction is constructed at the intersection of the warp and weft of the texture, so that the micro / nano structure and the woven texture form an optical coupling. Step 6: Gradient anodizing. The workpiece is placed in a composite electrolyte. The oxidation current density is controlled in stages to create a thickness gradient in the oxide film between the texture protrusion area and the groove area, thus preserving the three-dimensional shape of the texture. Step 7: Texture enhancement and optical activation. First, plasma is used to bombard the oxidized textured surface in a directional manner. Then, the workpiece is immersed in a solution containing optical activation components, so that the activation components adhere to the surface of the micro-nano structure. Step 8: Customized preparation of dynamic gloss layer. A metallic gloss layer is deposited on the workpiece surface using magnetron sputtering. During the sputtering process, the target angle and workpiece movement trajectory are adjusted to create a reflectivity difference between textured and non-textured areas of the gloss layer, achieving directional matching between dynamic gloss and carbon fiber texture. Step 9: Integrated coating of transparent protective layer. A protective coating with both wear resistance and light transmittance is applied to the surface of the metallic luster layer. During the coating process, the coating flow rate is controlled to ensure that the coating is evenly filled in the texture grooves. Step 10: Segmented curing and shaping. The workpiece coated with the protective layer is first pre-cured at low temperature to initially shape the coating, and then deep cured at high temperature to ensure that the protective layer, gloss layer and texture structure are tightly bonded, and finally a long aluminum product with carbon fiber woven texture and dynamic gloss is obtained.

[0006] In a further embodiment of the present invention, in step 1, the height and width of the textured preform protrusion are designed according to the ratio of carbon fiber monofilaments, and the surface of the protrusion is treated with a rounded transition to avoid scratching the aluminum substrate during the extrusion process.

[0007] In a further embodiment of the present invention, in step 5, the arrangement direction of the micro-nano optical structure forms a preset angle with the warp and weft lines of the carbon fiber weave texture, so that the optical effect generated by the incident light after passing through the micro-nano structure is superimposed with the visual effect of the texture.

[0008] In a further embodiment of the present invention, in step 6, the first stage of gradient anodizing uses a low current density to allow the oxide film to grow preferentially in the textured groove region, and the second stage uses a high current density to allow the oxide film to thicken in the textured protrusion region, forming a thickness gradient.

[0009] In a further embodiment of the present invention, in step 7, the optically activating component can enhance the refraction and diffraction effect of the micro / nano structure on visible light, so that the micro / nano structure exhibits more obvious optical changes from different viewing angles.

[0010] In a further embodiment of the present invention, in step 8, by adjusting the composition of the target material for magnetron sputtering, the metallic luster layer exhibits differentiated reflections under illumination of different wavelengths of light.

[0011] In a further embodiment of the present invention, in step 1, the textured preformed protrusions are evenly distributed on the inner wall of the mold cavity at a preset spacing to ensure that the basic texture of the extruded long aluminum profile surface is continuous and consistent.

[0012] In a further embodiment of the present invention, in step 5, the size and shape of the micro-nano optical structure are designed according to the target dynamic gloss effect, so that the optical effect is adapted to the visual style of the carbon fiber texture.

[0013] In a further embodiment of the present invention, in step 7, after the optical activation component is attached to the surface of the micro / nano structure, the activation component is fixed by low-temperature drying.

[0014] In a further embodiment of the present invention, in step 8, the target material for magnetron sputtering is an alloy target of multiple metals, and the reflectivity and color change range of the metallic luster layer are controlled by adjusting the alloy composition ratio.

[0015] The beneficial effects of this invention are: 1. Through a combination of processes including "texture pre-forming extrusion - synergistic laser - texture enhancement and optical activation," a molecular-level fusion of realistic carbon fiber physical texture and dynamic laser luster has been achieved for the first time on the surface of long aluminum products. The shallow surface basic texture in the extrusion stage provides homologous guidance for texture formation. Femtosecond lasers simultaneously construct carbon fiber-like woven textures and adapt micro-nano optical structures. Combined with plasma enhancement and optical activation, the three-dimensional texture at the intersection of warp and weft is made clearer. The directional gloss deposition of magnetron sputtering allows the dynamic luster to transition gradient along the texture direction. From different viewing angles, it can present a visual effect of color jumping and pattern flowing, completely surpassing the single and rigid effect of traditional water transfer printing and lamination processes, and greatly enhancing the aesthetics of the product.

[0016] 2. Constructing a composite protective system consisting of an aluminum substrate, a gradient anodizing film, a metallic luster layer, and a transparent protective layer. Gradient anodizing, through staged control of current density, ensures the oxide film completely covers the texture and micro / nano structure, protecting the substrate while preventing texture fading and wear. The integrated coating of the transparent protective layer ensures uniform filling within the texture grooves, and combined with segmented curing and shaping, the protective layer possesses both high hardness and high light transmittance, effectively resisting daily scratches, sweat, and chemical corrosion. Simultaneously, the entire process is suitable for continuous production of long aluminum products, solving the problems of poor texture continuity and uneven film layer in traditional processes, ensuring high product durability while meeting the needs of industrial mass production. Attached Figure Description

[0017] Figure 1 This is a flowchart of the steps of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0019] In the description of this application, it should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0020] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, the first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0021] It should be noted that in the description of this application, the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0022] It should be noted that, in this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0023] This embodiment provides a method for treating the surface of long aluminum products with carbon fiber woven texture and dynamic gloss, aiming to solve the problems of existing water transfer printing and film lamination processes, such as monotonous texture, poor adhesion, and inability to achieve synergistic integration of texture and dynamic gloss. It also adapts to the continuous production needs of long aluminum products. The specific steps are as follows: Step 1: Profile Extrusion Pretreatment. Aluminum substrate with a purity ≥99.5% is heated to a plastic state and then extruded into a long aluminum profile through a customized extrusion die with built-in textured pre-formed protrusions. The substrate can also be a high-quality aluminum alloy. The textured pre-formed protrusions are made of high-quality aluminum alloy and are distributed strictly along the warp and weft of the carbon fiber weave along the inner wall of the die cavity. The height and width of the protrusions are designed in a 1:1 ratio to the actual carbon fiber monofilament, and the surface of the protrusions is rounded to avoid scratches caused by contact between the aluminum substrate and the sharp edges of the protrusions during extrusion. Through the compression and adaptation between the aluminum substrate and the protrusions during extrusion, a shallow basic texture layer, homologous to the subsequent target texture, is formed on the surface of the profile. This basic texture not only provides precise positioning guidance for the subsequent laser process, avoiding texture misalignment caused by processing errors in the length direction of the long aluminum profile, but also pre-constructs a three-dimensional prototype of the carbon fiber texture, reducing the amount of material removed during subsequent laser processing, improving process efficiency, and strengthening the bonding between the texture and the aluminum substrate, avoiding the problem of texture layer separation from the substrate in traditional processes.

[0024] Step 2: Precise cutting and end-face shaping. A CNC cutting machine with a vision positioning system is used. A vision camera captures the basic texture features on the surface of the long aluminum profile, cutting it to the target length based on texture continuity. This ensures the integrity of the texture at both ends of the cut workpiece, avoiding end texture breakage caused by positioning deviations in traditional cutting. After cutting, a CNC grinding head performs a chamfering process on the end face of the workpiece. This eliminates the safety hazards to operators during subsequent grinding and cleaning processes caused by sharp edges, and prevents film accumulation or peeling during subsequent oxidation and coating processes. This ensures the consistency of the overall surface quality of the workpiece, making it particularly suitable for applications requiring high end-face smoothness, such as electronic device bezels and automotive trim strips.

[0025] Step 3: Adaptive grinding and polishing. A CNC grinding machine with pressure feedback sensors and laser surface contour recognition is used to process the workpiece. First, rough grinding is performed: 180-240 grit silicon carbide abrasive is selected. The contact pressure between the grinding head and the workpiece surface is dynamically adjusted by a pressure sensor to quickly remove surface scratches, oxide scale, and other defects generated during profile extrusion, while preserving the overall shape of the basic texture and avoiding over-grinding that could cause the texture to disappear. Next, fine grinding is performed: 600-800 grit diamond abrasive is used, and the grinding pressure is reduced. A laser contour scanner is used to scan the microstructure of the basic texture in real time. The grinding head's movement trajectory is adjusted based on the scan data to clarify the grooves and raised edges of the basic texture, reducing the grinding marks left by rough grinding. Finally, mirror polishing is performed: a flexible polyurethane polishing head is used with nano-grade alumina polishing fluid at low pressure to achieve the required surface roughness while ensuring the complete preservation of the microstructure of the basic texture. This adaptive grinding process not only solves the problem of uneven surface flatness of long workpieces caused by traditional fixed pressure grinding, but also provides a highly clean and flat substrate for subsequent laser processing, ensuring the accurate formation of laser textures.

[0026] Step 4: Targeted degreasing and cleaning, employing a three-stage cleaning process of "spray degreasing - targeted ultrasonic cleaning - rinsing and drying". First, spray degreasing is performed: the workpiece is placed in a sealed cleaning chamber, and a 5%-8% alkaline degreasing agent is sprayed onto the workpiece surface at specific pressure in a 360° manner. This chemical conversion quickly removes abrasive debris, oil, and other impurities remaining on the workpiece surface from the grinding process. Next, targeted ultrasonic cleaning is performed: the workpiece is transferred to an ultrasonic cleaning tank with texture positioning function. A vision system identifies the groove positions of the basic texture, and the energy focusing direction of the ultrasonic generator is adjusted so that the ultrasonic energy is mainly concentrated in the groove area, specifically removing small impurities remaining in the grooves. This targeted cleaning design solves the problem of difficult-to-clean groove impurities caused by the uniform energy distribution of traditional ultrasonic cleaning. Finally, rinsing and drying are performed: the workpiece is rinsed multiple times with high-resistivity deionized water to ensure complete removal of degreasing agent residue. The workpiece is then placed in a hot air drying oven for drying, with nitrogen protection during the drying process to prevent oxidation of the workpiece surface. Targeted degreasing and cleaning not only ensures the cleanliness of the workpiece surface, but also avoids the interference of impurities on subsequent laser and oxidation processes. In particular, it ensures that there are no impurities clogging the basic texture grooves, providing a clean space for the subsequent construction of micro and nano structures.

[0027] Step 5: Texture-Micro / Nano Structure Collaborative Laser Etching. The workpiece is processed using a computer-controlled femtosecond laser. First, a carbon fiber-like woven texture pattern adapted to the base texture is generated through computer modeling, including parameters such as the intersection angle of warp and weft lines, line width, and spacing. A micro / nano optical structure model is designed based on the target dynamic gloss effect. Then, the workpiece is fixed on a multi-axis CNC platform, and the laser head etchs the base texture area on the workpiece surface along a preset path. On one hand, by controlling the laser energy density and scanning speed, a carbon fiber-like woven texture is etched onto the base texture, restoring the three-dimensional woven texture of carbon fiber. On the other hand, a micro / nano optical structure is simultaneously constructed at the intersection of the warp and weft lines of the texture. This micro / nano optical structure consists of periodically arranged nano-protrusions or grooves, with their arrangement direction forming a preset angle with the warp and weft lines of the carbon fiber woven texture. The structural dimensions are designed according to the target optical effect. By using synergistic lasers, the micro-nano structure and the woven texture are optically coupled: when incident light is irradiated, part of the light is reflected by the woven texture to present the visual effect of carbon fiber, while the other part of the light is refracted and diffracted by the micro-nano structure to produce dynamic luster. The two are superimposed to form a unique visual effect of "texture flowing with luster", which completely solves the problem of separation of texture and luster in traditional processes. At the same time, the ultra-short pulse characteristics of femtosecond lasers avoid thermal damage to the aluminum substrate, ensuring clear texture edges and complete micro-nano structure morphology.

[0028] Step 6: Gradient anodizing. The workpiece is placed in a composite electrolyte composed of sulfuric acid, organic acid, and nano-silica particles. Anodizing is performed by controlling the current density in stages. First stage: Low current density is used, and the electrolyte temperature is controlled within a specific range. At this stage, the oxide film preferentially grows in the textured groove area because the surface area of ​​the groove area is larger, the current density is relatively concentrated, and the oxide film growth rate is faster than in the raised areas, forming an initial thickness difference. Second stage: The current density is increased, and the electrolyte temperature is decreased. At this stage, the oxide film growth rate in the raised areas accelerates, gradually forming a thickness gradient. During the oxidation process, a circulating filtration system is used to maintain the uniformity of the electrolyte composition, avoiding uneven film layers caused by differences in electrolyte concentration on long workpieces. This gradient anodizing process ensures that the oxide film completely covers the woven texture and micro / nano structure, sealing them inside the oxide film and effectively preventing texture wear and micro / nano structure damage during subsequent use. It also preserves the three-dimensional shape of the texture through thickness gradient. The thicker oxide film in the raised areas enhances light reflection and creates a contrast between light and dark areas with the groove areas, further highlighting the three-dimensionality of the carbon fiber texture. At the same time, the nano-silica particles in the composite electrolyte are embedded in the oxide film, improving the hardness and wear resistance of the film layer.

[0029] Step 7: Texture Enhancement and Optical Activation, employing a composite process of "plasma bombardment-optical activation". First, directional plasma bombardment is performed: the workpiece is placed in a vacuum plasma treatment chamber, a mixture of argon and oxygen is introduced, a specific plasma power is set, and the treatment time is specified. By adjusting the angle of the plasma spray gun, the plasma primarily acts on the raised edges of the texture and the surface of the micro / nano structures. The high-energy particles of the plasma remove minute defects on the oxide film surface, making the texture edges sharper and the contours of the micro / nano structures clearer. Simultaneously, the roughness of the oxide film surface is increased, enhancing the adhesion of subsequent optical activation components. Next, optical activation is performed: the workpiece is transferred to a solution containing optical activation components and kept at a specific temperature for a specific time. Through immersion adsorption, the activation components are uniformly adhered to the surface of the micro / nano structures. Finally, the workpiece is placed in a low-temperature drying oven to dry, fixing the activation components. The optically activated component has excellent light scattering and refraction properties, which can enhance the refraction and diffraction effect of micro and nanostructures on visible light. When not activated, the dynamic gloss change angle of the micro and nanostructure is small, but after activation, the change angle can be significantly expanded, making the gloss change more obvious from different viewing angles. At the same time, the binding of the activated component with the oxide film is stable, preventing it from falling off in subsequent processes and ensuring the long-term stability of the dynamic gloss effect.

[0030] Step 8: Customized preparation of the dynamic gloss layer. A metallic gloss layer is deposited on the workpiece surface using magnetron sputtering. The directional distribution of the gloss layer is achieved through "target angle adjustment - workpiece trajectory control". First, the workpiece is fixed on a rotatable magnetron sputtering fixture, which can reciprocate along its length. An aluminum-silver-rare earth alloy target is selected for sputtering. By adjusting the angle between the target and the workpiece surface, sputtered particles are mainly deposited on the raised areas of the texture and the surface of micro-nano structures. During the sputtering process, a specific vacuum level is maintained, and specific sputtering power and deposition time are set to ultimately form a metallic gloss layer of a specific thickness. By coordinating the control of the target angle and the workpiece trajectory, the gloss layer thickness in the textured area is made thicker than that in the non-textured area, creating a difference in reflectivity. The textured area has high reflectivity, while the non-textured area has low reflectivity. When the viewing angle changes, the high reflectivity gloss in the textured area contrasts with the low reflectivity background in the non-textured area. The dynamic gloss presents a gradient transition along the texture direction, achieving the effect of "dynamic gloss and carbon fiber texture orientation matching". This avoids the problem of "gloss covering texture" caused by the uniform distribution of gloss layer in traditional magnetron sputtering. At the same time, the selection of aluminum-silver-rare earth alloy target can be adjusted by adjusting the alloy composition ratio to precisely control the color change range of the gloss layer, further enriching the appearance options of the product.

[0031] Step 9: Integrated Coating of the Transparent Protective Layer. A "nano-silica-polyurethane" organic-inorganic hybrid protective coating is applied to the surface of the metallic gloss layer using a "controlled-speed curtain coating-leveling curing" method. First, the protective coating is heated to a specific temperature to reduce its viscosity. The coating is then evenly applied to the workpiece surface using a curtain coating device. During the curtain coating process, the workpiece's moving speed and the coating's spraying rate are controlled to ensure a uniform liquid film is formed on the workpiece surface. Subsequently, the workpiece is placed on a horizontal flow platform and leveled for a specific time under specific temperature and humidity conditions. During leveling, the coating naturally fills the texture grooves due to gravity, and the leveling time is controlled to prevent excessive coating flow that could lead to groove accumulation. The coating thickness is controlled within a specific range to ensure that the coating completely covers the metallic gloss layer without obscuring texture details. This transparent protective coating combines high hardness, high light transmittance, and excellent weather resistance. On the one hand, it can effectively resist scratches, sweat, alcohol, and cleaning agents in daily use, protecting the metallic luster layer and woven texture from damage. On the other hand, the high light transmittance ensures that the visual effect of dynamic luster and carbon fiber texture is not obstructed, achieving "protection and appearance in balance". This solves the problems of traditional protective coatings that either have poor light transmittance and obscure the texture or have low hardness and are easily worn.

[0032] Step 10: Segmented Curing and Shaping. A segmented process of "low-temperature pre-curing - high-temperature deep curing" is used to process the workpiece coated with the protective layer. First, low-temperature pre-curing is performed: the workpiece is placed in a hot air curing oven and kept at that temperature for a specific time, allowing the solvent in the protective coating to evaporate slowly and the coating to initially set, preventing bubbles and cracks caused by rapid solvent evaporation during subsequent high-temperature curing. Next, high-temperature deep curing is performed: the pre-cured workpiece is transferred to a curing oven and kept at that temperature for a specific time, allowing the resin components in the coating to fully cross-link and cure, forming a dense protective film. Nitrogen gas is used for protection during the curing process to prevent oxidation and discoloration of the workpiece surface. The segmented curing process solves the problems of uneven coating shrinkage and poor adhesion to the gloss layer caused by one-time high-temperature curing, while ensuring complete curing of the protective layer. After curing, the adhesion between the protective layer and the metallic gloss layer meets the standards, and the curing degree of the coating in different areas of long workpieces is small, ensuring consistent overall performance. The resulting long aluminum strips possess both the three-dimensional woven texture of carbon fiber and a dynamic luster that changes with the viewing angle. They also exhibit excellent wear resistance and corrosion resistance, making them widely applicable in high-end consumer electronics bezels, automotive trim strips, and sports equipment accessories.

[0033] In this embodiment, in step 1, the height and width of the textured preform protrusion are designed according to the proportion of carbon fiber monofilaments, and the surface of the protrusion is treated with a rounded transition to avoid scratching the aluminum substrate during extrusion. This design accurately replicates the size proportions of carbon fiber monofilaments, making the basic texture closer to the shape of real carbon fiber, laying the foundation for the realism of subsequent laser textures; the rounded transition treatment avoids scratching the aluminum substrate from the source of the process, reducing the scrap rate. When the protrusion of the traditional mold has a sharp edge, the scratch rate of the aluminum substrate is high during extrusion. After adopting the rounded transition, the scratch rate can be significantly reduced, while protecting the mold protrusion from wear, extending the mold service life, and reducing production costs. It is especially suitable for industrial continuous extrusion production, ensuring the consistency of the basic texture and the surface quality of the workpiece during mass production.

[0034] In this embodiment, in step 5, the arrangement direction of the micro-nano optical structure forms a preset angle with the warp and weft threads of the carbon fiber woven texture, so that the optical effect generated by the incident light after passing through the micro-nano structure is superimposed with the visual effect of the texture. Through the preset angle design, when incident light shines, the diffracted light generated by the micro-nano structure and the reflected light from the woven texture superimpose at a specific angle. When the viewing angle is parallel to the warp and weft threads, the texture visual effect is dominant; when the viewing angle deflects, the dynamic gloss of the micro-nano structure gradually becomes prominent, forming a progressive visual change of "texture-dominant - texture and gloss fusion - gloss-dominant," avoiding visual disorder caused by mutual interference between the two optical effects. Simultaneously, the preset angle can be adjusted according to product requirements. For example, for electronic device frames, a specific angle can be selected to make the gloss change softer; for automotive trim strips, a specific angle can be selected to make the gloss change more pronounced, enhancing the personalized design space of the product appearance and solving the problem of the monotonous visual effect of traditional fixed-angle micro-nano structures.

[0035] In this embodiment, in step 6, the first stage of gradient anodizing uses a low current density to allow the oxide film to grow preferentially in the textured groove area, while the second stage uses a high current density to thicken the oxide film in the textured raised area, forming a thickness gradient. This staged current control design precisely matches the oxidation requirements of different texture areas: the low current in the first stage ensures sufficient oxidation in the groove area, avoiding insufficient oxidation and thin, easily worn films caused by low current density in the groove area; the high current in the second stage allows for the formation of a thicker oxide film in the raised area, enhancing the wear resistance and reflectivity of the raised area. Test data shows that the wear resistance of the raised area after gradient oxidation is significantly improved compared to traditional uniform oxidation, and the corrosion resistance of the groove area is significantly improved. At the same time, the thickness gradient allows the oxide film to perfectly match the three-dimensional shape of the texture, without obscuring texture details, solving the problem of weakened texture three-dimensionality caused by the uniform thickness of traditional uniform oxide films.

[0036] In this embodiment, in step 7, the optically activating component enhances the refraction and diffraction of visible light by the micro / nanostructure, making the micro / nanostructure exhibit more obvious optical changes from different viewing angles. The refractive index of the optically activating component is much higher than that of the oxide film. After adhering to the surface of the micro / nanostructure, it increases the refraction angle and diffraction intensity of incident light within the micro / nanostructure. When unactivated, the intensity of the gloss change in the micro / nanostructure is low; after activation, it is significantly enhanced, and the viewing angle range of the gloss change is greatly expanded, allowing for clear observation of the dynamic gloss effect even in low-light environments. Simultaneously, the activating component exhibits good chemical stability, remaining insoluble and unreacted in common media such as sweat and alcohol, ensuring that the dynamic gloss effect maintains a high level even after many years of product use, thus solving the problem of easy decay of the gloss effect in traditional micro / nanostructures.

[0037] In this embodiment, step 8 involves adjusting the target composition of the magnetron sputtering to achieve differentiated reflections of the metallic gloss layer under different wavelengths of light. Adjusting the target composition allows for precise control of the gloss layer's spectral reflectance characteristics: for example, increasing the aluminum content and decreasing the silver content enhances the reflectivity of the gloss layer in the blue light band, resulting in a cool-toned dynamic gloss; conversely, increasing the silver content and decreasing the aluminum content enhances the reflectivity of the gloss layer in the yellow light band, resulting in a warm-toned dynamic gloss. Adding a small amount of rare earth elements further optimizes the uniformity of reflection in the gloss layer, preventing "spot" problems caused by excessive localized reflection. This design enables the production of dynamic gloss products with different hues using the same process, without requiring equipment changes. Simply adjusting the target composition can meet diverse market demands, reduce production switching costs, and improve process flexibility.

[0038] In this embodiment, in step 1, the textured pre-formed protrusions are evenly distributed on the inner wall of the mold cavity at a preset spacing, ensuring that the basic texture on the surface of the extruded long aluminum profile is continuous and consistent. The preset spacing is designed based on the density of the target carbon fiber texture. High-precision CNC machining ensures that the spacing error of the protrusions on the inner wall of the mold cavity is small. During the extrusion process, a constant extrusion rate and temperature are maintained to ensure that the basic texture on the surface of the long aluminum profile is continuous without breaks and the texture misalignment error is small. This uniform distribution design solves the problem of discontinuous texture on long profiles caused by uneven protrusion spacing in traditional molds, ensuring that the texture can extend continuously along the long strip direction during subsequent laser processing. It is especially suitable for long automotive trim strips, industrial profiles, and other products, improving the overall appearance consistency of the product and avoiding visual defects caused by discontinuous textures.

[0039] In this embodiment, in step 5, the size and shape of the micro / nano optical structure are designed according to the target dynamic gloss effect, so that the optical effect matches the visual style of the carbon fiber texture. For products pursuing "delicate gloss," a nano-protrusion structure with a specific period and height can be designed, which produces a soft dynamic gloss change that complements the fine carbon fiber texture; for products pursuing "strong gloss," a nano-groove structure with a specific period and depth can be designed, which produces a more vivid dynamic gloss change that matches the rough carbon fiber texture style. At the same time, the shape of the micro / nano structure can be selected as circular, square, or hexagonal. The gloss change of the circular structure is more uniform, the gloss change of the square structure is directional, and the hexagonal structure has both uniformity and directionality, further enriching the design dimensions of the optical effect, achieving a precise match between "texture style and gloss effect," and solving the problem of monotonous appearance style caused by the fixed size and shape of traditional micro / nano structures.

[0040] In this embodiment, in step 7, after the optical activation component is attached to the surface of the micro / nano structure, it is fixed by low-temperature drying. The low-temperature drying process avoids the damage to the morphology of the micro / nano structure caused by high temperatures. If higher temperatures are used for drying, the edges of the micro / nano structure are easily blurred due to thermal deformation, leading to a decrease in gloss effect. Low-temperature drying ensures that the outline integrity of the micro / nano structure remains at a high level. Simultaneously, during the low-temperature drying process, the activation component slowly loses water and solidifies, forming a thin layer tightly bonded to the oxide film. Adhesion tests show that the peel strength of the activation component is high, far exceeding the effect of natural drying after traditional impregnation. This prevents the activation component from falling off in subsequent processes such as magnetron sputtering and coating of protective layers, ensuring a stable and long-lasting optical activation effect. Furthermore, the low-temperature process has lower energy consumption, meeting the requirements of green production.

[0041] In this embodiment, in step 8, the target material for magnetron sputtering is an alloy target of multiple metals. By adjusting the proportion of alloy components, the reflectivity and color variation range of the metallic gloss layer are controlled. The alloy target has superior sputtering performance compared to a single metal target: a single aluminum target is prone to "target poisoning" during sputtering, leading to a decrease in sputtering rate. Adding a specific proportion of silver can significantly reduce the probability of target poisoning, stabilizing the sputtering rate. Adding a small amount of rare earth elements can refine the grain structure of the gloss layer, resulting in lower surface roughness and improved gloss smoothness. By adjusting the proportion of alloy components, the reflectivity can be precisely controlled within a wide range, and the color variation range can cover multiple color systems from silver-white to light gold, with small color uniformity errors. This solves the problem of narrow reflectivity and color adjustment range of a single metal target, meeting the differentiated gloss texture requirements of various high-end products.

[0042] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for carbon fiber woven texture and dynamic gloss treatment of the surface of a long aluminum product, characterized by, The method comprises the following steps: Step 1: profile extrusion pretreatment, extruding the aluminum base material through the built-in texture preformed protrusions of the customized extrusion die into long aluminum profiles; Step 2: accurate cutting and end face shaping, using cutting equipment with visual positioning to cut the long aluminum profiles into target length workpieces, and at the same time, performing arc chamfering treatment on the end faces of the workpieces; Step 3: adaptive grinding and polishing, using a grinding device with pressure feedback and surface profile recognition function, first removing the extrusion defects on the profile surface through coarse grinding, then making the micro-morphology of the basic texture clear through fine grinding, and finally performing mirror polishing through a flexible polishing head; Step 4: directional degreasing and cleaning, first spraying the workpiece surface with an alkaline degreasing agent for degreasing, then performing targeted cleaning on the basic texture grooves of the workpiece surface through an ultrasonic cleaning system, and finally rinsing with deionized water and drying; Step 5: texture-micro-nano structure synergistic laser, using a computer numerically controlled femtosecond laser device to form a carbon fiber woven texture on the basic texture area of the workpiece surface, and simultaneously constructing a micro-nano optical structure that is adapted to the texture direction at the intersection of the texture warp and weft; Step 6: gradient anodic oxidation, placing the workpiece in a composite electrolyte for chemical conversion, and by adjusting the oxidation current density in stages, forming a thickness gradient of the oxidation film in the texture protrusion area and groove area; Step 7: texture strengthening and optical activation, first using plasma to perform directional bombardment on the textured surface after oxidation, and then immersing the workpiece in a solution containing an optical activation component; Step 8: dynamic gloss layer customized preparation, using a magnetron sputtering process to deposit a metal gloss layer on the workpiece surface, and adjusting the target material angle and workpiece movement trajectory during the sputtering process; Step 9: integrated coating of transparent protective layer, controlling the coating flow rate; Step 10: segmented curing and shaping, first performing low-temperature pre-curing, and then performing high-temperature deep curing, to obtain a long aluminum product.

2. The method of claim 1, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 1, the texture preformed protrusions are distributed along the inner wall of the die cavity according to the warp and weft direction of the carbon fiber woven texture, and by matching the extrusion of the aluminum base material with the protrusions, a shallow surface layer of basic texture that is homologous to the target texture is formed on the profile surface. The height and width of the texture preformed protrusions are designed according to the ratio of a carbon fiber monofilament, and the surface of the protrusions is treated with a circular arc transition to avoid scratching the aluminum base material during extrusion.

3. The method of claim 1, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 5, the arrangement direction of the micro-nano optical structure and the warp and weft lines of the carbon fiber woven texture form a preset angle, so that the optical effects generated after the incident light passes through the micro-nano structure are superimposed with the visual effects of the texture.

4. The method of claim 1, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 6, the first stage of gradient anodic oxidation uses a low current density to make the oxidation film grow first in the texture groove area, and the second stage uses a high current density to thicken the oxidation film in the texture protrusion area, forming a thickness gradient.

5. The method of claim 1, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 7, the activation component adheres to the surface of the micro-nano structure, and the optical activation component can enhance the refraction and diffraction effects of the micro-nano structure on visible light, so that the micro-nano structure presents more obvious optical changes at different viewing angles.

6. The method of claim 1, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 8, the sputtering makes the gloss layer form reflectivity difference between the textured area and the non-textured area, realizing dynamic gloss and directional matching of carbon fiber texture, and by adjusting the target material composition of the magnetron sputtering, the metal gloss layer presents differential reflection under different wavelengths of light.

7. The method of claim 2, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 1, the texture pre-form protrusions are uniformly distributed on the inner wall of the mold cavity at a predetermined interval, ensuring that the surface of the extruded long aluminum profile has continuous and consistent basic texture.

8. The method of claim 3, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 5, the size and shape of the micro-nano optical structure are designed according to the target dynamic gloss effect, so that the optical effect and the visual style of the carbon fiber texture are adapted.

9. The method of claim 5, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 7, after the optical activation component is attached to the surface of the micro-nano structure, low-temperature drying is used to fix the activation component.

10. The method of claim 6, wherein the carbon fiber woven texture and dynamic gloss treatment of the long strip aluminum product surface is characterized by, In step 8, the target material of the magnetron sputtering is an alloy target of multiple metals, and by adjusting the alloy composition ratio, the reflectivity and color change range of the metal gloss layer are controlled.

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