Passivation solution, aluminum alloy components and their preparation methods

Abstract

This application relates to a passivation treatment solution, aluminum alloy components, and a method for preparing the same. The passivation treatment solution comprises a solvent and components dispersed in the solvent at the following concentrations: fluorozirconate 5 g / L–30 g / L, fluorinated silane coupling agent 10 ml / L–50 ml / L, polyphenol complexing agent 1 g / L–8 g / L, and silicate 5 g / L–25 g / L. The passivation treatment solution, through a multi-component synergistic formulation composed of fluorozirconate, fluorinated silane coupling agent, polyphenol complexing agent, and silicate, exhibits different functions and molecular bridging synergistic effects. After passivation treatment of anodized aluminum alloys, the alkaline corrosion resistance of the aluminum alloys can be significantly enhanced.

Description

Technical Field

[0001] This application relates to the field of metal surface treatment, and in particular to passivation solutions, aluminum alloy components and their preparation methods. Background Technology

[0002] Aluminum alloys are gradually becoming the main material for shower valve bodies and fittings due to their low cost and lightweight properties. However, aluminum alloys are prone to corrosion in long-term water environments. Anodizing is a common surface treatment technology for aluminum alloys, which forms an oxide film on the surface of the aluminum material through electrochemical means, improving the material's corrosion resistance, wear resistance, and decorative properties. However, the anodized film has a porous structure, and in humid environments, the micropores can easily become channels for the penetration of corrosive media. In highly alkaline water environments, its resistance to alkaline corrosion is significantly insufficient.

[0003] Traditional anodic oxide film improvement technologies include hard anodizing, micro-arc oxidation, and chromate passivation. However, all of these technologies have limitations: hard anodizing is costly and unsuitable for thin-walled parts; micro-arc oxidation is energy-intensive and one of the most expensive surface treatment processes currently available, and it also has limitations in terms of appearance and color; while chromate passivation can significantly improve the corrosion resistance of aluminum alloys, it causes serious environmental pollution, and hexavalent chromium compounds are classified as carcinogens. Currently developed chromium-free passivation technologies mainly include fluorozirconate systems, silane systems, and vanadate systems. However, traditional chromium-free passivation treatments are still not ideal for protecting aluminum alloy shower valve bodies, faucets, and other components that are subject to prolonged water exposure, especially under high-alkalinity water conditions, where the film layer is prone to pitting corrosion and peeling. Summary of the Invention

[0004] Therefore, it is necessary to provide a passivation solution, an aluminum alloy component, and a method for preparing the same, in order to improve the alkali corrosion resistance of anodic aluminum oxide.

[0005] The first aspect of this application provides a passivation solution, the solution of which is as follows:

[0006] A passivation treatment solution includes a solvent and components dispersed in the solvent at the following concentrations:

[0007] Fluorozyrate 5g / L-30g / L, fluorinated silane coupling agent 10ml / L-50ml / L, polyphenol complexing agent 1g / L-8g / L, and silicate 5g / L-25g / L.

[0008] In some embodiments, the passivation solution contains the following components at concentrations:

[0009] Fluorozyrate 10g / L-20g / L, fluorosilane coupling agent 20ml / L-40ml / L, polyphenol complexing agent 2g / L-5g / L, and silicate 10g / L-20g / L.

[0010] In some embodiments, the passivation solution contains the following components at concentrations:

[0011] Fluorozironate 12g / L-18g / L, fluorinated silane coupling agent 25ml / L-35ml / L, polyphenol complexing agent 3g / L-4.5g / L, and silicate 12g / L-18g / L.

[0012] In some embodiments, the passivation solution further includes a pH buffer at a concentration of 1 g / L to 10 g / L.

[0013] In some embodiments, the pH buffer is selected from at least one of boric acid, citric acid, and tartaric acid.

[0014] In some embodiments, the concentration of the pH buffer is 3 g / L to 8 g / L.

[0015] In some embodiments, the concentration of the pH buffer is 4.5 g / L to 6.5 g / L.

[0016] In some embodiments, the passivation solution further includes a chelating agent at a concentration of 4 g / L to 18 g / L.

[0017] In some embodiments, the concentration of the chelating agent is 6 g / L-14 g / L.

[0018] In some embodiments, the concentration of the chelating agent is 8.5 g / L to 11.5 g / L.

[0019] In some embodiments, the chelating agent includes ethylenediaminetetraacetic acid (EDTA) and methylglycine diacetic acid (MGDIA), wherein the concentration of EDTA is 2 g / L-10 g / L and the concentration of MGDIA is 2 g / L-8 g / L.

[0020] In some embodiments, the concentration of ethylenediaminetetraacetic acid is 3 g / L-8 g / L, and the concentration of methylglycine diacetic acid is 3 g / L-6 g / L.

[0021] In some embodiments, the concentration of ethylenediaminetetraacetic acid is 3 g / L-8 g / L, and the concentration of methylglycine diacetic acid is 4 g / L-5.5 g / L.

[0022] In some embodiments, the passivation solution further includes a lubricating leveling agent at a concentration of 2 g / L to 10 g / L.

[0023] In some embodiments, the lubricating leveling agent is selected from at least one of polyethylene glycol, polyether-modified silicone, and fatty alcohol polyoxyethylene ether.

[0024] In some embodiments, the concentration of the lubricating leveling agent is 3 g / L to 6 g / L.

[0025] In some embodiments, the concentration of the lubricating leveling agent is 4 g / L-5 g / L.

[0026] In some embodiments, the fluorozirconate includes at least one of potassium fluorozirconate and ammonium fluorozirconate.

[0027] In some embodiments, the silicate includes sodium silicate.

[0028] In some embodiments, the fluorinated silane coupling agent includes perfluorooctyltrimethyloxysilane.

[0029] In some embodiments, the polyphenol complexing agent includes tannic acid.

[0030] In some embodiments, the solvent includes water.

[0031] In some embodiments, the passivation solution has a pH of 8.0-10.0.

[0032] The second aspect of this application provides a method for preparing an aluminum alloy component, as follows:

[0033] A method for preparing an aluminum alloy component includes the following steps:

[0034] Anodizing is performed on aluminum alloy workpieces;

[0035] The passivation solution described in any of the above embodiments is used to passivate the preset position of the anodized aluminum alloy workpiece.

[0036] In some embodiments, the passivation treatment is performed at a temperature of 25°C-40°C for a time of 3-5 minutes.

[0037] The third aspect of this application provides an aluminum alloy component, as follows:

[0038] An aluminum alloy component is prepared by the preparation method described in any of the above embodiments.

[0039] Compared with existing solutions, the above-mentioned passivation solution, aluminum alloy components, and their preparation methods have the following advantages:

[0040] In the above passivation solution, fluorozirconate is used as the main film-forming agent, and the F in fluorozirconate... - Ions can corrode the surface of anodic oxide films, Zr 4+Subsequently, hydrolysis generates ZrO2 and Zr(OH)4 nanoparticles as precipitates. These nanoparticles deposit inside and on the surface of the anodic oxide film's micropores, forming an extremely thin zirconium-based conversion film, effectively sealing the micropores initially. The silanol groups formed after hydrolysis of the fluorinated silane coupling agent can undergo condensation reactions with the hydroxyl groups on the aluminum alloy oxide film surface, forming high-strength Si-O-Al covalent bonds. Furthermore, the fluorinated alkyl groups are arranged outwards, imparting extremely low surface energy to the aluminum alloy surface and generating a hydrophobic effect, effectively preventing corrosive ions in water from contacting the film layer. Multiple hydroxyl groups in the polyphenol complexing agent molecule can react with Al... 3+ Zr 4 + Complexation reactions occur, forming stable complexes, thereby increasing the crosslinking density and compactness of the film. Silicates can play a synergistic role in film formation. After hydrolysis, silicates generate silica sol, which can participate in film formation, fill the gaps between film layers, and improve film density. Furthermore, silicate films themselves have good alkali resistance.

[0041] The passivation solution described above is a multi-component synergistic formula consisting of fluorozirconate, fluorinated silane coupling agent, polyphenol complexing agent and silicate. Each component plays a different role, and there is a molecular bridging synergistic effect between the different components. After passivation treatment of anodized aluminum alloy, the alkaline corrosion resistance of the aluminum alloy can be significantly enhanced. Detailed Implementation

[0042] To facilitate understanding of this application, a more comprehensive description of the application will be provided below with reference to specific embodiments. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0044] One embodiment of the passivation solution includes a solvent and components dispersed in the solvent at the following concentrations:

[0045] Fluorozyrate 5g / L-30g / L, fluorinated silane coupling agent 10ml / L-50ml / L, polyphenol complexing agent 1g / L-8g / L, and silicate 5g / L-25g / L.

[0046] The passivation solution described above is composed of a multi-component synergistic formula consisting of fluorozirconate, fluorinated silane coupling agent, polyphenol complexing agent, and silicate. Through the synergistic effect of molecular bridging between the components, the passivation treatment of anodized aluminum alloy can significantly enhance the aluminum alloy's resistance to alkali corrosion.

[0047] Fluorozirconate is the main film-forming agent. The F in fluorozirconate... - Ions can corrode the surface of anodic oxide films, Zr 4+ Subsequently, hydrolysis generates ZrO2 and Zr(OH)4 nanoparticle precipitates. These nanoparticles are deposited inside and on the surface of the micropores of the anodic oxide film, forming an extremely thin zirconium-based conversion film, which effectively and initially seals the micropores.

[0048] Fluorozirates include, but are not limited to, at least one of potassium fluorozirconate and ammonium fluorozirconate. In some examples, the fluorozirconate is potassium fluorozirconate.

[0049] The concentration of fluorozirconate is 5 g / L-30 g / L. More preferably, the concentration of fluorozirconate is 10 g / L-20 g / L. Even more preferably, the concentration of fluorozirconate is 12 g / L-18 g / L. In some specific examples, the concentration of fluorozirconate is, for example, 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L, 25 g / L, 26 g / L, 27 g / L, 28 g / L, 29 g / L, 30 g / L, etc.

[0050] The silanol groups formed after hydrolysis of the fluorinated silane coupling agent can undergo a polycondensation reaction with the hydroxyl groups on the surface of the aluminum alloy oxide film to form a high-strength Si-O-Al covalent bond. Furthermore, the fluorinated alkyl groups at the long chain ends are arranged outwards, giving the aluminum alloy surface extremely low surface energy and generating a hydrophobic effect, effectively blocking the contact between corrosive ions in water and the film layer.

[0051] Fluorinated silane coupling agents, including but not limited to perfluorooctyltrimethyloxysilane.

[0052] The concentration of the fluorosilane coupling agent is 10 ml / L-50 ml / L. Further, the concentration of the fluorosilane coupling agent is 20 ml / L-40 ml / L. Even further, the concentration of the fluorosilane coupling agent is 25 ml / L-35 ml / L. In some specific examples, the concentrations of the fluorosilane coupling agents are, for example, 10 ml / L, 12 ml / L, 14 ml / L, 16 ml / L, 18 ml / L, 20 ml / L, 22 ml / L, 24 ml / L, 26 ml / L, 28 ml / L, 20 ml / L, 22 ml / L, 24 ml / L, 26 ml / L, 28 ml / L, 30 ml / L, 32 ml / L, 34 ml / L, 36 ml / L, 38 ml / L, 40 ml / L, 42 ml / L, 44 ml / L, 46 ml / L, 48 ml / L, 50 ml / L, etc.

[0053] Multiple hydroxyl groups in polyphenol complexing agents can react with Al 3+ Zr 4+ A complexation reaction occurs, forming a stable complex, thereby increasing the crosslinking density and compactness of the film.

[0054] Polyphenol complexing agents include, but are not limited to, tannic acid. In some examples, the polyphenol complexing agent is tannic acid. Multiple ortho- and ortho-phenolic hydroxyl groups in the molecule can react with Al... 3+ Zr 4+ A complexation reaction occurs, forming a stable complex. In addition, tannic acid can also act as a corrosion inhibitor.

[0055] The concentration of the polyphenol complexing agent is 1 g / L-8 g / L. More preferably, the concentration of the polyphenol complexing agent is 2 g / L-5 g / L. Even more preferably, the concentration of the polyphenol complexing agent is 3 g / L-4.5 g / L. In some specific examples, the concentration of the polyphenol complexing agent is, for example, 1 g / L, 1.5 g / L, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 4 g / L, 4.5 g / L, 5 g / L, 5.5 g / L, 6 g / L, 6.5 g / L, 7 g / L, 7.5 g / L, 8 g / L, etc.

[0056] Silicates can play a synergistic role in film formation. After hydrolysis, silicates generate silica sol, which can participate in film formation, fill the gaps between film layers, and improve film density. Furthermore, silicate films themselves have good alkali resistance, effectively improving resistance to alkali corrosion.

[0057] Silicates include, but are not limited to, sodium silicate.

[0058] The concentration of silicate is 5 g / L to 25 g / L. More preferably, the concentration of silicate is 10 g / L to 20 g / L. Further preferably, the concentration of silicate is 12 g / L to 18 g / L. In some specific examples, the concentration of silicate is, for example, 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, 21 g / L, 22 g / L, 23 g / L, 24 g / L, 25 g / L, etc.

[0059] In some examples, the passivation solution also includes a pH buffer. The pH buffer is used to stabilize the pH of the passivation solution and prevent pH fluctuations during the passivation process. - The rapid consumption of ions leads to a sharp rise in pH, thereby ensuring the smooth progress of the film-forming reaction.

[0060] pH buffers include, but are not limited to, at least one of boric acid, citric acid, and tartaric acid.

[0061] In some examples, the concentration of the pH buffer is 1 g / L to 10 g / L. Further, the concentration of the pH buffer is preferably 3 g / L to 8 g / L. Even further, the concentration of the pH buffer is preferably 4.5 g / L to 6.5 g / L. In some specific examples, the concentration of the pH buffer is, for example, 1 g / L, 1.5 g / L, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 4 g / L, 4.5 g / L, 5 g / L, 5.5 g / L, 6 g / L, 6.5 g / L, 7 g / L, 7.5 g / L, 8 g / L, 8.5 g / L, 9 g / L, 9.5 g / L, 10 g / L, etc.

[0062] In some examples, the passivation solution also includes a lubricating leveling agent. The lubricating leveling agent can significantly reduce the surface tension of the passivation solution, allowing the passivation solution to spread and wet the surface of the aluminum alloy more evenly, which helps to form a smoother and more uniform passivation film.

[0063] Lubricating and leveling agents include, but are not limited to, at least one of polyethylene glycol, polyether-modified silicone, and fatty alcohol polyoxyethylene ether.

[0064] In some examples, the lubricating leveling agent is polyethylene glycol. In some examples, the molecular weight of polyethylene glycol is 400-600.

[0065] In some examples, the concentration of the lubricating leveling agent is 2 g / L-10 g / L. Further, the concentration of the lubricating leveling agent is preferably 3 g / L-6 g / L. Even further, the concentration of the lubricating leveling agent is preferably 4 g / L-5 g / L. In some specific examples, the concentration of the lubricating leveling agent is, for example, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 4 g / L, 4.5 g / L, 5 g / L, 5.5 g / L, 6 g / L, 6.5 g / L, 7 g / L, 7.5 g / L, 8 g / L, 8.5 g / L, 9 g / L, 9.5 g / L, 10 g / L, etc.

[0066] In some examples, the passivation solution also includes a chelating agent. The chelating agent reacts with metal ions to form chelates, reducing the adverse effects of metal ions on film formation.

[0067] In some examples, the concentration of the chelating agent is 4 g / L to 18 g / L. Further, the concentration of the chelating agent is preferably 6 g / L to 14 g / L. Even further, the concentration of the chelating agent is preferably 8.5 g / L to 11.5 g / L. In some specific examples, the concentration of the chelating agent is, for example, 4 g / L, 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L, 16 g / L, 17 g / L, 18 g / L, etc.

[0068] Chelating agents include ethylenediaminetetraacetic acid (EDTA) and methylglycinic acid diacetic acid (MGDA). EDT acts as both a chelating agent and a stabilizer. It forms stable chelates with aluminum ions, preventing irregular precipitation and promoting the formation of a dense passivation film. MGDA acts as both a chelating agent and a dispersant. It complexes with hard water ions such as calcium and magnesium, as well as impurity metal ions introduced during the process, effectively reducing scale and impurity deposition on the passivation film surface and preventing defects. The combined use of EDTA and MGDA effectively improves film quality.

[0069] In some examples, the concentration of ethylenediaminetetraacetic acid (EDTA) is 2 g / L to 10 g / L. More preferably, the concentration of EDTA is 3 g / L to 8 g / L. Even more preferably, the concentration of EDTA is 4.5 g / L to 6 g / L. In some specific examples, the concentration of EDTA is, for example, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 4 g / L, 4.5 g / L, 5 g / L, 5.5 g / L, 6 g / L, 6.5 g / L, 7 g / L, 7.5 g / L, 8 g / L, 8.5 g / L, 9 g / L, 9.5 g / L, 10 g / L, etc.

[0070] In some examples, the concentration of methylglycinoacetic acid is 2 g / L to 8 g / L. More preferably, the concentration of methylglycinoacetic acid is 3 g / L to 6 g / L. Even more preferably, the concentration of methylglycinoacetic acid is 4 g / L to 5.5 g / L. In some specific examples, the concentration of methylglycinoacetic acid is, for example, 2 g / L, 2.5 g / L, 3 g / L, 3.5 g / L, 4 g / L, 4.5 g / L, 5 g / L, 5.5 g / L, 6 g / L, 6.5 g / L, 7 g / L, 7.5 g / L, 8 g / L, etc.

[0071] The solvent can be, but is not limited to, water.

[0072] In some examples, the pH value of the passivation treatment solution is 8.0-10.0, specifically, for example, 8.0, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9.0, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, 10.0, etc. Preferably, the pH value of the passivation treatment solution is 8.5-9.5. More preferably, the pH value of the passivation treatment solution is 8.8-9.2.

[0073] The pH value of the passivation solution can be adjusted by adding a pH adjuster. The amount of pH adjuster added is set according to the desired pH value of the passivation solution. A pH adjuster can be, for example, but is not limited to, ammonia.

[0074] Furthermore, this application also provides a method for treating an anodized layer on an aluminum alloy.

[0075] One embodiment of a method for treating an anodized layer on an aluminum alloy includes the following steps:

[0076] Step S1: Perform anodizing treatment on the aluminum alloy workpiece.

[0077] Step S2: Passivate the preset positions of the anodized aluminum alloy workpiece using a passivation solution.

[0078] In step S1, in some examples, the electrolyte used for the anodizing process includes sulfuric acid and aluminum sulfate. The concentration of sulfuric acid is, for example, 150 g / L-200 g / L, specifically 150 g / L, 160 g / L, 170 g / L, 180 g / L, 190 g / L, 200 g / L, etc. The concentration of aluminum sulfate is, for example, 2 g / L-15 g / L, specifically 2 g / L, 4 g / L, 6 g / L, 8 g / L, 10 g / L, 12 g / L, 14 g / L, etc.

[0079] In some examples, the voltage applied during the anodizing process is 10V-15V, specifically 10V, 11V, 12V, 13V, 14V, 15V, etc. In some examples, the temperature of the anodizing process is 15℃-20℃, specifically 15℃, 16℃, 17℃, 18℃, 19℃, 20℃, etc. In some examples, the anodizing process time is 30min-50min, specifically 30min, 35min, 40min, 45min, 50min, etc. In some examples, the thickness of the anodized layer is 10μm-15μm, specifically 10μm, 11μm, 12μm, 13μm, 14μm, 15μm, etc.

[0080] In some examples, the aluminum alloy workpiece is pretreated before the anodizing process.

[0081] In some examples, the pretreatment includes degreasing, alkaline etching, and descaling performed sequentially.

[0082] In some examples, the treatment solution used for degreasing comprises the following components at the following concentrations:

[0083] Sodium phosphate 15g / L-25g / L, sodium carbonate 10g / L-15g / L, and polyoxyethylene polyoxypropylene ether 1g / L-5g / L.

[0084] In some examples, the degreasing temperature is 30℃-60℃, specifically 30℃, 40℃, 50℃, 60℃, etc. The degreasing time is 3min-10min, specifically 4min, 6min, 8min, 10min, etc.

[0085] In some examples, the treatment solution used for alkaline etching includes the following components at the following concentrations:

[0086] Sodium hydroxide 60g / L-70g / L, sodium phosphate 10g / L-20g / L, and sodium carbonate 10-20g / L.

[0087] In some examples, the alkaline etching temperature is 45℃-70℃, specifically 45℃, 50℃, 55℃, 60℃, 65℃, 70℃, etc. The alkaline etching time is 1min-3min, specifically 1min, 1.5min, 2min, 2.5min, 3min, etc.

[0088] In some examples, the treatment solution used for stain removal includes components at the following concentrations:

[0089] Nitric acid 100g / L-150g / L and ferric nitrate 10g / L-20g / L.

[0090] In some examples, the stain removal treatment temperature is 25℃-40℃, specifically 25℃, 30℃, 35℃, 40℃, etc. The stain removal treatment temperature is 1min-3min, specifically 1min, 1.5min, 2min, 2.5min, 3min, etc.

[0091] In step S2, the passivation solution can be any of the passivation solutions described above.

[0092] In some examples, the passivation temperature is 25℃-40℃. In some specific examples, the passivation temperature is, for example, 25℃, 26℃, 27℃, 28℃, 29℃, 30℃, 31℃, 32℃, 33℃, 34℃, 35℃, 36℃, 37℃, 38℃, 39℃, 40℃, etc.

[0093] In some examples, the passivation time is 3-5 minutes. In some specific examples, the passivation time is, for example, 3 minutes, 3.5 minutes, 4 minutes, 4.5 minutes, 5 minutes, etc.

[0094] In some examples, the method for treating the anodized layer on the aluminum alloy after passivation also includes a post-treatment step for the anodized layer.

[0095] In some examples, post-processing includes:

[0096] Step S3, staining treatment;

[0097] Step S4, sealing the hole;

[0098] Step S5: Drying treatment.

[0099] In step S3, the dyeing process is performed on the anodic oxide layer, for example, by using a dyeing solution containing organic pigments.

[0100] The concentration of organic pigment is, for example, 5 g / L-10 g / L, specifically 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L, 10 g / L, etc. The dyeing temperature is, for example, 30℃-45℃, specifically 30℃, 33℃, 36℃, 39℃, 42℃, 45℃, etc. The dyeing time is, for example, 0.5 min-10 min, specifically 0.5 min, 2 min, 4 min, 6 min, 8 min, 10 min, etc.

[0101] It is understandable that in other examples, the above staining process may not be performed.

[0102] In step S4, further sealing treatment can more fully fill the micropores of the oxide film, improving corrosion resistance, wear resistance and stain resistance.

[0103] The sealing solution used in the sealing process may include components with the following concentrations:

[0104] Nickel acetate 5g / L-10g / L, sodium methylene bis(naphthalene) sulfonate 0.5g / L-1.5g / L, sodium acetate 0.5g / L-1g / L, and boric acid 0.1g / L-0.5g / L.

[0105] The sealing temperature is, for example, 75℃-95℃, specifically 75℃, 77℃, 79℃, 81℃, 83℃, 85℃, 87℃, 89℃, 91℃, 93℃, 95℃, etc. The sealing time is, for example, 30min-60min, specifically 30min, 35min, 40min, 45min, 50min, 55min, 60min, etc.

[0106] It is understandable that in other examples, the above-mentioned hole sealing process may not be performed.

[0107] In step S5, the drying temperature is, for example, 100℃-120℃, specifically 100℃, 105℃, 110℃, 115℃, 120℃, etc. The drying time is, for example, 20min-30min, specifically 20min, 22min, 24min, 26min, 28min, 30min, etc.

[0108] It is understandable that in other examples, the above drying process may not be necessary.

[0109] Furthermore, this application also provides an aluminum alloy component, which is prepared by any of the preparation methods described above.

[0110] The aforementioned aluminum alloy components include, but are not limited to, bathroom fixtures, such as shower valve bodies, shower heads, faucets, and shelves.

[0111] The following specific embodiments further illustrate the present invention. These specific embodiments are provided to better understand the present invention, but are not intended to limit the scope of the invention and do not constitute a limitation on its content or protection.

[0112] Example 1

[0113] This embodiment provides a passivation treatment solution, comprising deionized water and components at the following concentrations:

[0114] Potassium fluorozirconate 12 g / L, perfluorooctyltrimethyloxysilane 25 ml / L, tannic acid 3 g / L, sodium silicate 12 g / L, boric acid 4.5 g / L, polyethylene glycol 4 g / L, ethylenediaminetetraacetic acid 4.5 g / L, and methylglycine diacetic acid 4 g / L.

[0115] Example 2

[0116] This embodiment provides a passivation treatment solution, comprising deionized water and components at the following concentrations:

[0117] Potassium fluorozirconate 15g / L, perfluorooctyltrimethyloxysilane 30ml / L, tannic acid 4g / L, sodium silicate 15g / L, boric acid 5.5g / L, polyethylene glycol 4.5g / L, ethylenediaminetetraacetic acid 5g / L, and methylglycine diacetic acid 4.5g / L.

[0118] Example 3

[0119] This embodiment provides a passivation treatment solution, comprising deionized water and components at the following concentrations:

[0120] Potassium fluorozirconate 18 g / L, perfluorooctyltrimethyloxysilane 35 ml / L, tannic acid 4.5 g / L, sodium silicate 18 g / L, boric acid 6.5 g / L, polyethylene glycol 5 g / L, ethylenediaminetetraacetic acid 6 g / L, and methylglycine diacetic acid 5 g / L.

[0121] Example 4

[0122] This embodiment provides a passivation treatment solution, comprising deionized water and components at the following concentrations:

[0123] Potassium fluorozirconate 10g / L, perfluorooctyltrimethyloxysilane 20ml / L, tannic acid 2g / L, sodium silicate 10g / L, boric acid 3g / L, polyethylene glycol 3g / L, ethylenediaminetetraacetic acid 3g / L, methylglycine diacetic acid 3g / L.

[0124] Example 5

[0125] This embodiment provides a passivation treatment solution, comprising deionized water and components at the following concentrations:

[0126] Potassium fluorozirconate 20g / L, perfluorooctyltrimethyloxysilane 40ml / L, tannic acid 5g / L, sodium silicate 20g / L, boric acid 8g / L, polyethylene glycol 6g / L, ethylenediaminetetraacetic acid 8g / L, methylglycine diacetic acid 6g / L.

[0127] Example 6

[0128] This embodiment provides a passivation treatment solution, comprising deionized water and components at the following concentrations:

[0129] Potassium fluorozirconate 5g / L, perfluorooctyltrimethyloxysilane 10ml / L, tannic acid 1g / L, sodium silicate 5g / L, boric acid 1g / L, polyethylene glycol 2g / L, ethylenediaminetetraacetic acid 2g / L, methylglycine diacetic acid 2g / L.

[0130] Example 7

[0131] This embodiment provides a passivation treatment solution, comprising deionized water and components at the following concentrations:

[0132] Potassium fluorozirconate 30g / L, perfluorooctyltrimethyloxysilane 50ml / L, tannic acid 8g / L, sodium silicate 25g / L, boric acid 10g / L, polyethylene glycol 10g / L, ethylenediaminetetraacetic acid 10g / L, methylglycine diacetic acid 8g / L.

[0133] Comparative Example 1

[0134] The only difference between this comparative example and Example 2 is that it does not contain tannic acid.

[0135] Comparative Example 2

[0136] The only difference between this comparative example and Example 2 is that it does not contain potassium fluorozirconate.

[0137] Comparative Example 3

[0138] The only difference between this comparative example and Example 2 is that it does not contain perfluorooctyltrimethyloxysilane.

[0139] Comparative Example 4

[0140] The only difference between this comparative example and Example 6 is that it does not contain sodium silicate.

[0141] Aluminum alloy surface treatment examples

[0142] Take the shower valve body, which is made of 6061 aluminum alloy, and perform surface treatment on it as follows:

[0143] Step 1: Pre-treat the shower valve body, which consists of degreasing, alkaline etching, and dust removal.

[0144] Step 2: Anodize the shower valve body. The electrolyte for anodizing includes 180 g / L sulfuric acid and 10 g / L aluminum sulfate. The current density of the process is 1.5 A / dm³. 2 The temperature was 20℃ and the time was 40 min. The average thickness of the formed anodic oxide layer was 13 μm.

[0145] Step 3: Passivate the shower valve body using the passivation solutions from the above embodiments and comparative examples. The process temperature is 30°C and the time is 4 minutes.

[0146] Step 4: Seal the shower valve body. The treatment solution includes nickel acetate (5g / L-10g / L), sodium methylene bis(naphthalene)sulfonate (0.5g / L-1.5g / L), sodium acetate (0.5g / L-1g / L), and boric acid (0.1g / L-0.5g / L). The process temperature is 85℃, and the time is 30 minutes. After completion, perform a drying process.

[0147] The following performance tests were conducted on the shower valve body that underwent the above surface treatment:

[0148] Neutral salt spray test: The test shall be conducted in accordance with the "Neutral Salt Spray Test (NSS Test)" in standard GB / T 10125-2021.

[0149] Alkaline drop test: Performed according to the "Alkali Drop Test" in standard GB / T5237.2.

[0150] Water contact angle test: Performed in accordance with the "Contact Angle Measurement" standard in ASTM D7334-08.

[0151] The performance test results are shown in Table 1.

[0152] Table 1

[0153]

[0154] As can be seen from the test results in Table 1, Examples 1-7 use a multi-component composite system of fluorozirconate, fluorinated silane coupling agent, polyphenol complexing agent, and silicate, and are combined with auxiliary components such as lubricating leveling agent, chelating agent, and pH buffer. Their overall performance is significantly better than that of Comparative Examples 1-4, which lack a single core component.

[0155] The neutral salt spray test durations of Examples 1-7 all exceeded 800 hours, with a maximum of 1400 hours. The alkaline drop test durations were all above 520 seconds, reaching a maximum of 800 seconds, significantly longer than Comparative Examples 1-4 (neutral salt spray test 350-520 hours, alkaline drop test 150-300 seconds). This indicates that the film-forming and sealing effect of fluorozirconate, the hydrophobic barrier effect of the fluorosilane coupling agent, the cross-linking and densifying effect of the polyphenol complexing agent, and the synergistic film-forming effect of silicate form a highly efficient synergistic effect, effectively blocking the penetration of corrosive media and significantly improving the alkaline corrosion resistance of anodic aluminum oxide.

[0156] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0157] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A passivation treatment solution, characterized in that, Includes the solvent and the components dispersed in the solvent at the following concentrations: Fluorozyrate 5g / L-30g / L, fluorinated silane coupling agent 10ml / L-50ml / L, polyphenol complexing agent 1g / L-8g / L, and silicate 5g / L-25g / L.

2. The passivation treatment solution as described in claim 1, characterized in that, The passivation solution contains the following components at the following concentrations: Fluorozyrate 10g / L-20g / L, fluorosilane coupling agent 20ml / L-40ml / L, polyphenol complexing agent 2g / L-5g / L, and silicate 10g / L-20g / L; Preferably, the passivation solution contains the following components at the following concentrations: Fluorozironate 12g / L-18g / L, fluorinated silane coupling agent 25ml / L-35ml / L, polyphenol complexing agent 3g / L-4.5g / L, and silicate 12g / L-18g / L.

3. The passivation solution as described in claim 1, characterized in that, The passivation solution also includes a pH buffer with a concentration of 1 g / L to 10 g / L; Preferably, the pH buffer is selected from at least one of boric acid, citric acid, and tartaric acid; Preferably, the concentration of the pH buffer is 3 g / L-8 g / L; Preferably, the concentration of the pH buffer is 4.5 g / L to 6.5 g / L.

4. The passivation solution according to any one of claims 1-3, characterized in that, The passivation solution also includes a chelating agent with a concentration of 4 g / L-18 g / L; Preferably, the concentration of the chelating agent is 6 g / L-14 g / L; Preferably, the concentration of the chelating agent is 8.5 g / L-11.5 g / L; Preferably, the chelating agent comprises ethylenediaminetetraacetic acid (EDTA) and methylglycine diacetic acid (MGDIA), wherein the concentration of EDTA is 2 g / L-10 g / L and the concentration of MGDIA is 2 g / L-8 g / L. Preferably, the concentration of ethylenediaminetetraacetic acid is 3 g / L-8 g / L, and the concentration of methylglycine diacetic acid is 3 g / L-6 g / L; Preferably, the concentration of ethylenediaminetetraacetic acid is 3 g / L-8 g / L, and the concentration of methylglycine diacetic acid is 4 g / L-5.5 g / L.

5. The passivation solution according to any one of claims 1-3, characterized in that, The passivation treatment solution also includes a lubricating and leveling agent with a concentration of 2g / L-10g / L; Preferably, the lubricating leveling agent is selected from at least one of polyethylene glycol, polyether-modified silicone, and fatty alcohol polyoxyethylene ether; Preferably, the concentration of the lubricating leveling agent is 3g / L-6g / L; Preferably, the concentration of the lubricating leveling agent is 4g / L-5g / L.

6. The passivation solution according to any one of claims 1-3, characterized in that, The passivation solution meets at least one of the following characteristics (1)-(5): (1) The fluorozirconate includes at least one of potassium fluorozirconate and ammonium fluorozirconate; (2) The silicate includes sodium silicate; (3) The fluorinated silane coupling agent includes perfluorooctyltrimethyloxysilane; (4) The polyphenol complexing agent includes tannic acid; (5) The solvent includes water.

7. The passivation solution according to any one of claims 1-3, characterized in that, The passivation solution has a pH value of 8.0-10.

0.

8. A method for preparing an aluminum alloy component, characterized in that, Includes the following steps: Anodizing is performed on aluminum alloy workpieces; The passivation solution according to any one of claims 1-7 is used to passivate the preset position of the anodized aluminum alloy workpiece.

9. The method for preparing aluminum alloy components as described in claim 8, characterized in that, The passivation treatment is performed at a temperature of 25℃-40℃ for 3-5 minutes.

10. An aluminum alloy component, characterized in that, It is prepared by the preparation method described in claim 8 or 9.

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