A surface treatment method for a metal or alloy and a metal or alloy article

Abstract

This invention provides a surface treatment method for metals or alloys, and metal or alloy articles thereof. The surface treatment method involves forming an organic-inorganic hybrid layer on the surface of an anodic oxide layer on at least one surface of the metal or alloy; wherein the organic-inorganic hybrid layer is primarily composed of silicon dioxide, and also contains carbon-containing groups filling the spatial network structure formed by the silicon dioxide. At least one surface of the metal or alloy article has an anodic oxide layer and an organic-inorganic hybrid layer. The organic-inorganic hybrid layer is primarily composed of silicon dioxide, and contains carbon-containing groups filling the space between it. The technical solution provided by this invention, by forming an organic-inorganic hybrid layer on the surface of the anodic oxide layer, can provide excellent corrosion resistance, extremely high hardness, and exceptionally good car wash resistance, meeting the requirements of all current automotive OEMs.

Description

Technical Field

[0001] This invention relates to a surface treatment method for metals or alloys and metal or alloy products, belonging to the field of metal and alloy treatment technology. Background Technology

[0002] Aluminum alloy trim strips are increasingly used in automotive exterior parts due to their unique metallic texture and low material density, and are favored by many car owners, especially high-end customers. Due to the material's characteristics, aluminum alloy trim strips cannot be used directly as automotive exterior parts; they require surface treatment before use. After surface treatment, aluminum alloy trim strips offer more diverse and personalized appearances, and their surface hardness and corrosion resistance are significantly improved. Currently, commonly used surface treatment methods for aluminum alloy trim strips include anodizing, baking paint, and powder coating.

[0003] As automotive exterior components, maintaining their decorative effect over time under various operating conditions is the most basic requirement. Currently, after anodizing, aluminum alloy surfaces undergo conventional chemical sealing, significantly improving surface hardness and corrosion resistance, which meets the needs of a considerable number of customers. However, with high-end customers demanding more from decorative components, especially with the use of highly alkaline car wash liquids and automatic car wash machines, traditional pH 12.5 or pH 13.0 anodized products are prone to corrosion or scratches, resulting in loss of luster, whitening, and other changes, thus negating their decorative effect.

[0004] To improve corrosion resistance, especially to meet alkali resistance requirements above pH 13.5, anodic electrophoresis technology has been used in recent years. This process involves depositing a polyacrylate coating on the surface of the anodic oxide layer via electrophoresis. This organic coating offers excellent corrosion resistance, but it also has significant drawbacks. For end users, its hardness is not high enough to meet stringent car wash resistance tests. For manufacturers, precisely because it is a highly corrosion-resistant organic coating, rework of the product and the hangers requires substantial costs for paint stripping. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention aims to provide a surface treatment method for metals or alloys and metal or alloy products, which forms an organic-inorganic hybrid layer on the surface of the anodic oxide layer to meet the corrosion resistance and car wash resistance requirements of exterior parts products, while reducing the manufacturing cost of the products.

[0006] To solve the above-mentioned technical problems, the present invention first provides a surface treatment method for metals or alloys, which involves forming an organic-inorganic hybrid layer on the surface of an anodic oxide layer on at least one surface of the metal or alloy.

[0007] The organic-inorganic hybrid layer is mainly composed of silicon dioxide and contains carbon-containing groups that fill the spaces between the silicon dioxide-formed network structure.

[0008] The present invention also provides a metal or alloy article having at least one surface having an anodic oxide layer and an organic-inorganic hybrid layer, wherein the organic-inorganic hybrid layer is formed on the surface of the anodic oxide layer;

[0009] The organic-inorganic hybrid layer is mainly composed of silicon dioxide and contains carbon-containing groups that fill the spaces between the silicon dioxide-formed network structure.

[0010] According to a specific embodiment of the present invention, preferably, the carbon-containing group includes one or more combinations of epoxy, alkyl, alkenyl, alkynyl, and aryl groups, more preferably epoxy and / or alkyl.

[0011] According to a specific embodiment of the present invention, the present invention uses an anodic oxide layer as a substrate and forms an organic-inorganic hybrid layer thereon. The provided organic-inorganic hybrid layer comprises a main structure with silicon dioxide as the main component. Preferably, the mass ratio of Si to C elements in the organic-inorganic hybrid layer is 0.33-4.3. The present invention has found that by controlling the ratio of silicon-containing and carbon-containing components in the organic-inorganic hybrid layer within the above-mentioned range: on the one hand, the silicon dioxide content can be kept within a suitable range, avoiding problems such as difficulty in film formation or poor film formation during construction caused by excessive silicon dioxide content, and preventing quality problems such as easy cracking of the film layer; on the other hand, the carbon group content can be kept within a suitable range, avoiding the adverse effects of excessive carbon groups filling the silicon dioxide main structure on the film layer hardness. The resulting organic-inorganic hybrid layer has excellent corrosion resistance, extremely high hardness and scratch resistance, and can simultaneously possess extremely high hardness and the characteristics of easy film formation and resistance to cracking. The mass ratio of Si to C in the organic-inorganic hybrid layer is more preferably 0.42-3.7, and even more preferably 0.58-2.6. Within the mass ratio range of Si to C provided by this invention, the mass ratio of the specific organic-inorganic hybrid layer can be controlled as needed, for example, controlled to 0.42-1.9, 0.58-1.2, 2.6-3.7, etc.

[0012] According to a specific embodiment of the present invention, preferably, the organic-inorganic hybrid layer is formed by the dehydration condensation of two or more organic oxysilanes (containing alkoxy, aryloxy, acyloxy and / or alkyl carbonyl groups).

[0013] According to a specific embodiment of the present invention, preferably, the organooxysilane includes at least one or a combination of two or more of dialkoxysilanes, trialkoxysilanes, and tetraalkoxysilanes.

[0014] According to a specific embodiment of the present invention, preferably, at least one of the two or more organooxysilanes that generate the oligomer contains an epoxy group. More preferably, the organooxysilane containing the epoxy group includes one or a combination of two or more of the following: 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, 3-(2,3-epoxypropoxy)propyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane.

[0015] According to a specific embodiment of the present invention, preferably, at least one of the two or more organooxysilanes that generate the oligomer does not contain an epoxy group. More preferably, the organooxysilane that does not contain an epoxy group includes general formula R a SiX (4-a) In the compounds shown, a represents 0-3, R represents a non-hydrolyzable group selected from alkyl, alkenyl, alkynyl, and aryl, and X represents a hydrolyzable group selected from alkoxy, aryloxy, acyloxy, and alkyl carbonyl. Specifically, the organooxysilanes that do not contain epoxy groups include one or more combinations of methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraacetylsilane, methylphenyldimethoxysilane, dimethoxydiacetoxysilane, diethyldiacetoxysilane, di-tert-butoxydiacetoxysilane, diethoxydiphenylsilane, and trimethylphenoxysilane.

[0016] This invention preferably uses at least one epoxy-containing organooxysilane and at least one epoxy-free organooxysilane to produce oligomers. This combination brings the following advantages: 1. Epoxy groups can improve the density of the coating, thereby improving salt spray resistance and alkali resistance. At the same time, epoxy groups can also make the coating bond more tightly to the anodized surface after immersion in water at 80℃-98℃ for 1-10 minutes. Actual production has found that if the anodized layer is not immersed in water at 80℃-98℃, the workpiece is easily scratched by hands, gloves or other items that come into contact with the workpiece during the transfer process, thus affecting the appearance. Experiments show that by introducing epoxy-containing organooxysilanes and controlling their content in the system, the coating can bond more tightly to the surface after hot water immersion, improving the corrosion resistance of the product; 2. Adding at least one epoxy-free organooxysilane can provide the basic film structure of silica, ensuring the key performance of the coating, such as high hardness.

[0017] According to a specific embodiment of the present invention, preferably, the thickness of the organic-inorganic hybrid layer is 0.5 μm-5 μm. Specifically, when the mass ratio of Si to C in the organic-inorganic hybrid layer is 0.42-1.9, the thickness of the corresponding organic-inorganic hybrid layer is preferably 3 μm-5 μm; when the mass ratio of Si to C in the organic-inorganic hybrid layer is 2.6-3.7, the thickness of the corresponding organic-inorganic hybrid layer is preferably 0.5 μm-2.6 μm.

[0018] According to a specific embodiment of the present invention, preferably, the organic-inorganic hybrid layer is prepared by coating, such as common coating methods such as dip coating, spray coating, roller coating, brush coating and spin coating.

[0019] According to a specific embodiment of the present invention, preferably, the metal is aluminum or iron, and the alloy is an aluminum alloy or stainless steel.

[0020] According to a specific embodiment of the present invention, preferably, the thickness of the anodic oxide layer is 2μm-10μm, more preferably 4μm-7μm.

[0021] According to a specific embodiment of the present invention, the anodic oxide film layer can be obtained through conventional processes, and after obtaining the anodic oxide layer, it is first immersed in water at 80℃-98℃ for 1-10 minutes. In actual production, after anodizing, the workpiece needs to be transferred from the anodizing line fixture to the spraying line fixture. If the anodic oxide layer is not immersed in water at 80℃-98℃, the workpiece is easily scratched by hands, gloves, or other items that come into contact with the workpiece during the transfer process, thus affecting the aesthetic appearance. By immersing in water at 80℃-98℃, on the one hand, residual acid in the pores of the anodic oxide film can be cleaned more thoroughly, and on the other hand, more importantly, the scratch resistance of the oxide film layer can be improved, making the workpiece easier to handle during production operations.

[0022] According to a specific embodiment of the present invention, preferably, the metal or alloy product provided by the present invention is an external decorative item.

[0023] According to a specific embodiment of the present invention, preferably, the exterior trim is a high-hardness, scratch-resistant aluminum alloy exterior trim product.

[0024] The aluminum alloy exterior parts provided by this invention have corrosion resistance that meets the following requirements: they can withstand immersion in acidic solution with pH=1.0 for 10 minutes, a more preferred technical solution can reach 1 hour, and a further preferred technical solution can reach 24 hours; they can withstand immersion in alkaline solution with pH=13.5 for 10 minutes, a more preferred technical solution can reach 1 hour, and a further preferred technical solution can reach 2 hours.

[0025] The aluminum alloy exterior parts provided by this invention have a surface pencil hardness >5H, and more preferably a pencil hardness >6H.

[0026] The aluminum alloy exterior trim products provided by this invention meet the following car wash resistance requirements: using the car wash resistance test in the DIN EN ISO 20566 (2013) standard, the 60° gloss retention rate is >90%, and more preferably 95%.

[0027] According to a specific embodiment of the present invention, preferably, the exterior trim is an automotive exterior trim.

[0028] The technical solution provided by this invention forms an organic-inorganic hybrid layer on the surface of the anodic oxide layer, which can provide excellent corrosion resistance, extremely high hardness, and exceptionally good car wash resistance, thus meeting the requirements of all current car OEMs on the market. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of a specific embodiment of the high-hardness, scratch-resistant aluminum alloy exterior trim product provided by the present invention.

[0030] Figure 2 The results are from the energy dispersive spectroscopy (EDS) test of the first organic-inorganic hybrid layer.

[0031] Figure 3 The results are the energy dispersive spectroscopy (EDS) results for the second type of organic-inorganic hybrid layer.

[0032] Figure 4 The film cracking of organic-inorganic hybrid layers with different Si / C mass ratios is shown.

[0033] Figure 5 The appearance of organic-inorganic hybrid layers with different Si / C mass ratios.

[0034] Figure 6 The results of car wash tests for different products. Detailed Implementation

[0035] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

[0036] A specific embodiment of the high-hardness, scratch-resistant aluminum alloy exterior trim product provided by this invention has the following structure: Figure 1 As shown. The aluminum alloy exterior trim product includes an aluminum substrate 101, with anodized layers 201 and 202 on both sides of the substrate, and organic-inorganic hybrid layers 301 and 302 on the surfaces of the two anodized layers 201 and 202, respectively.

[0037] Example 1

[0038] Organic-inorganic hybrid layers with different Si / C mass ratios were prepared on the surface of an aluminum alloy substrate by coating, wherein:

[0039] (1) The first organic-inorganic hybrid layer:

[0040] The first type of organic-inorganic hybrid layer is formed by oligomers generated by the dehydration condensation of organooxysilanes. The organooxysilanes used are 3-(2,3-epoxypropoxy)propyltrimethoxysilane and methyltrimethoxysilane, with a mass ratio of 1.74. During the hydrolysis of silanes, methanol, ethanol, etc. are formed. After heating and curing, methanol and ethanol will evaporate from the system, which is equivalent to decarbonization.

[0041] The first organic-inorganic hybrid layer has a Si:C mass ratio of 0.67, and its energy spectrum is shown below. Figure 2 As shown;

[0042] The thickness of the first organic-inorganic hybrid layer is 3μm-5μm.

[0043] (2) The second type of organic-inorganic hybrid layer:

[0044] The second type of organic-inorganic hybrid layer is formed by oligomers generated by the dehydration condensation of organic oxysilanes. The organic oxysilanes used are 3-(2,3-epoxypropoxy)propyltriethoxysilane and tetraethoxysilane, with a mass ratio of 0.16.

[0045] The second type of organic-inorganic hybrid layer has a Si:C mass ratio of 3.66, and its energy spectrum is shown below. Figure 3 As shown;

[0046] The thickness of the second type of organic-inorganic hybrid layer is 0.5μm-1.5μm.

[0047] Depend on Figure 2 It can be seen that: in the first type of organic-inorganic hybrid layer, Si:C = 0.67, the organic content is high, and the film thickness can be made relatively thick while ensuring that the film quality meets the product appearance requirements.

[0048] Depend on Figure 3 It can be seen that the Si:C ratio in the second organic-inorganic hybrid layer is 3.66, and the organic portion is much smaller than that in the first organic-inorganic hybrid layer. To ensure that the film quality meets the product appearance requirements, the film thickness can only be made relatively thin. Therefore, it can be seen that the electron beam can penetrate the second organic-inorganic hybrid layer and detect the Al element signal on the substrate.

[0049] The above organic-inorganic hybrid layer was tested for pencil hardness, acid resistance, and alkali resistance. The acid resistance and alkali resistance tests were conducted using the following methods:

[0050] Under standard conditions, aluminum alloy parts with organic-inorganic hybrid layers on their surfaces are immersed in acidic or alkaline solutions of a specific pH. During this process, the test pieces with a diameter of 30-50 mm are kept immersed in the test solution. The samples are taken out for observation at regular intervals. If there are no defects such as blistering or peeling from the substrate surface, the test is considered qualified and the test continues. The duration of the last qualified test is recorded as the acid resistance or alkali resistance duration.

[0051] The test results are shown in Table 1 below:

[0052] Table 1

[0053] Pencil hardness Acid resistance pH=1 Alkali resistance pH=13.5 The first type of organic-inorganic hybrid layer 6H 36h 2.5h The second type of organic-inorganic hybrid layer 7H 48h 2.1h

[0054] As can be seen from the results recorded in Table 1, the organic-inorganic hybrid layer formed in Example 1 has high hardness and acid and alkali resistance, and can provide good protection for the surface of aluminum alloy substrate.

[0055] Example 2

[0056] Organic-inorganic hybrid layers with different Si / C mass ratios were prepared on the surface of an aluminum alloy substrate by coating. The film cracking behavior of the coatings was observed, and the test results were... Figure 4 As shown:

[0057] When the Si:C mass ratio in the coating is too high, especially when Si:C > 10, the coating is difficult to form, and even if it does, it is prone to cracking during curing. Figure 4 The third type of organic-inorganic hybrid layer shown in Figure (a) is formed by oligomers generated by the dehydration condensation of organic oxysilanes. The organic oxysilanes used are 3-(2,3-epoxypropoxy)propyltrimethoxysilane and tetramethoxysilane, with a ratio of 0.05. The Si:C mass ratio of this third type of organic-inorganic hybrid layer is 12.35. The entire front film layer is cracked, and the film thickness cannot be measured.

[0058] Even when the Si:C mass ratio in the coating decreases to >5, cracking can still occur in localized areas of the product (especially in areas where the film thickness is relatively thick due to the product's structure). Figure 4The fourth type of organic-inorganic hybrid layer shown in Figure (b) is formed by oligomers generated by the dehydration condensation of organooxysilanes. The organooxysilanes used are 3-(2,3-epoxypropoxy)propyltrimethoxysilane and tetramethoxysilane, with a ratio of 0.1. The Si:C mass ratio of this fourth type of organic-inorganic hybrid layer is 6.28. In areas without cracks, the film thickness is between 0.8 μm and 1.2 μm. In areas with cracks, the film thickness is between 1.6 μm and 2.1 μm.

[0059] When the Si:C mass ratio in the coating is within the suitable range required by this invention (Si:C = 0.33-4.3), appearance problems such as cracking can be avoided, resulting in a product with excellent appearance, such as... Figure 4 Figure (c) shows the fifth type of organic-inorganic hybrid layer, which is formed by the dehydration condensation of an organooxysilane. The organooxysilane used is 3-(2,3-epoxypropoxy)propyltrimethoxysilane and tetramethoxysilane, with a ratio of 2.2. The Si:C mass ratio of this fifth type of organic-inorganic hybrid layer is 0.67, and its film thickness is between 3 μm and 5 μm.

[0060] Example 3

[0061] Organic-inorganic hybrid layers with different Si / C mass ratios were prepared on the surface of aluminum alloy substrates by coating, and the appearance effects of the coatings were observed.

[0062] Figure 5 The image shows the appearance of organic-inorganic hybrid layers with different Si / C mass ratios under bar inspection light. The difference in product appearance quality can be seen from the reflection of the light tube on the product.

[0063] Figure 5 Figure (e) shows the appearance of the product surface without coating, with diffused light and shadow;

[0064] Figure 5 Figures (f) and (g) show the appearance of the product surface coated with an organic-inorganic hybrid layer, where:

[0065] Figure 5 The sixth type of organic-inorganic hybrid layer in Figure (f) is formed by the dehydration condensation of an organooxysilane to form an oligomer. The organooxysilane used is 3-(2,3-epoxypropoxy)propyltrimethoxysilane and tetramethoxysilane in a ratio of 0.28. The Si:C mass ratio of this sixth type of organic-inorganic hybrid layer is 2.6, and the film thickness is between 2.3 μm and 2.6 μm. Figure 5 As can be seen in Figure (f), the light and shadow of the lamp tube are clear, and the coating has an excellent appearance.

[0066] Figure 5The seventh type of organic-inorganic hybrid layer in Figure (g) is formed by the dehydration condensation of an organooxysilane to produce an oligomer. The organooxysilane used is 3-(2,3-epoxypropoxy)propyltrimethoxysilane and methyltrimethoxysilane in a ratio of 5. The Si:C mass ratio of this seventh type of organic-inorganic hybrid layer is 0.4, and the film thickness is between 3.4 μm and 4.2 μm. Figure 5 As can be seen in Figure (g), the orange peel texture is severe under the light and shadow of the lamp tube, resulting in a poor appearance that does not meet the requirements of high-end customers for external decorative parts.

[0067] Example 4

[0068] Organic-inorganic hybrid layers with different Si / C mass ratios were prepared on the surface of aluminum alloy substrates by coating, and car wash tests were conducted. The test results are shown in Table 2.

[0069] Figure 6 The image shown is a rendering of the vehicle after a wash resistance test according to the DIN EN ISO 20566 (2013) standard.

[0070] Figure 6 The (h) diagram shows a product from a traditional pH 13.0 process. Through Ni and silicate sealing, its surface has no coating; the outermost layer is an anodized film, which is highly hard and scratch-resistant. Figure 6 As shown in Figure (h), the surface after the car wash test only has slight scratches, but the drawback is that it cannot pass the alkali resistance test after the car wash test.

[0071] Figure 6 Figure (i) shows the product from the anodic electrophoresis pH 13.5 process. Through electrophoresis, an acrylic resin coating adheres to the surface of the anodic oxide layer; however, this coating has poor hardness. Figure 6 Figure (i) shows that the surface was severely scratched after the car wash test. The scratched coating also showed a rainbow sheen when viewed from the side, which is unacceptable for an exterior decorative product.

[0072] Figure 6 Figure (j) shows the product of the present invention, which has a first organic-inorganic hybrid layer of Example 1 on its surface. The Si:C mass ratio of the first organic-inorganic hybrid layer is 0.67, and its film thickness is between 3 μm and 5 μm. Figure 6 Figure (j) shows that the surface only has slight scratches after the car wash test, and it still meets the performance requirements such as alkali resistance after the car wash test.

[0073] Table 2. Car wash test data for different products

[0074]

[0075] Test method:

[0076] 1) Content: The Si / C mass ratio in the organic-inorganic hybrid layer was determined using SEM & EDS (electron microscope and energy dispersive spectroscopy, model: Zeiss Super 55).

[0077] 2) Film thickness: The cross-section of the organic-inorganic hybrid layer was observed using SEM & EDS (electron microscope and energy dispersive spectroscopy, model: Zeiss Super 55). The film thickness was accurately measured on the obtained cross-sectional images to obtain film thickness data.

[0078] 3) Car wash test: The test was conducted according to the car wash resistance test in DIN EN ISO 20566 (2013) standard, and the gloss data of the test sample was measured after 10 car wash cycles.

[0079] 4) Gloss: Use a gloss meter (model: BYK4586) to measure the gloss data of the test sample at a 60° angle.

[0080] 5) Alkali Resistance Test: Under room temperature conditions, a. For products using the traditional pH 13.0 process, immerse them in an alkaline solution with pH = 13.0 for 10 minutes and observe the surface corrosion. Corrosion and whitening are not allowed. b. For products using the anodic electrophoresis pH 13.5 process and the product of this invention, immerse them in an alkaline solution with pH = 13.5 for 10 minutes and observe the surface corrosion. Corrosion and whitening are not allowed. In the alkali resistance test, corrosion and whitening are considered unqualified, while the absence of corrosion and whitening is considered qualified. Preparation of pH = 13.0 alkaline solution: Dissolve 4.0g NaOH, 4.64g Na3PO4·12H2O, and 0.33g NaCl in 1L of deionized water. Preparation of pH = 13.5 alkaline solution: Dissolve 12.7g NaOH, 4.64g Na3PO4·12H2O, and 0.33g NaCl in 1L of deionized water.

Claims

1. A metal or alloy article having at least one surface having an anodic oxide layer and an organic-inorganic hybrid layer, wherein, The organic-inorganic hybrid layer is formed on the surface of the anodic oxide layer; The organic-inorganic hybrid layer is mainly composed of silicon dioxide and contains carbon-containing groups filling the spatial network structure formed by silicon dioxide. The mass ratio of Si to C in the organic-inorganic hybrid layer is 0.58-2.

6. The organic-inorganic hybrid layer is formed by the dehydration condensation of two or more organic oxysilanes; wherein at least one organic oxysilane contains an epoxy group and at least one organic oxysilane does not contain an epoxy group.

2. The metal or alloy article according to claim 1, wherein, The carbon-containing group includes one or more combinations of epoxy, alkyl, alkenyl, alkynyl, and aryl groups.

3. The metal or alloy article according to claim 2, wherein, The carbon-containing groups include epoxy groups and / or alkyl groups.

4. The metal or alloy article according to claim 1, wherein, The organooxysilanes include at least one or a combination of two or more of the following: dialkoxysilanes, trialkoxysilanes, and tetraalkoxysilanes.

5. The metal or alloy article according to claim 1, wherein, The organooxysilanes include at least one or a combination of two or more of the following: dialkoxysilanes, trialkoxysilanes, and tetraalkoxysilanes.

6. The metal or alloy article according to claim 5, wherein, The epoxy-containing organooxysilanes include one or more combinations of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, 3-(2,3-epoxypropoxy)propyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane.

7. The metal or alloy article according to claim 1, wherein, The organooxysilanes that do not contain epoxy groups include those of general formula R. a SiX (4-a) The compounds shown are 0-3, R represents a non-hydrolyzable group selected from alkyl, alkenyl, alkynyl and aryl, and X represents a hydrolyzable group selected from alkoxy, aryloxy, acyloxy and alkylcarbonyl.

8. The metal or alloy article according to claim 7, wherein, The organooxysilanes that do not contain epoxy groups include one or more combinations of methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraacetylsilane, methylphenyldimethoxysilane, dimethoxydiacetoxysilane, diethyldiacetoxysilane, di-tert-butoxydiacetoxysilane, diethoxydiphenylsilane, and trimethylphenoxysilane.

9. The metal or alloy article according to claim 1, wherein, The organooxysilanes that do not contain epoxy groups include those of general formula R. a SiX (4-a) The compounds shown are 0-3, R represents a non-hydrolyzable group selected from alkyl, alkenyl, alkynyl and aryl, and X represents a hydrolyzable group selected from alkoxy, aryloxy, acyloxy and alkylcarbonyl.

10. The metal or alloy article according to claim 9, wherein, The organooxysilanes that do not contain epoxy groups include one or more combinations of methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraacetylsilane, methylphenyldimethoxysilane, dimethoxydiacetoxysilane, diethyldiacetoxysilane, di-tert-butoxydiacetoxysilane, diethoxydiphenylsilane, and trimethylphenoxysilane.

11. The metal or alloy article according to any one of claims 1-4 and 6-10, wherein, The thickness of the organic-inorganic hybrid layer is 0.5 μm-5 μm.

12. The metal or alloy article according to claim 11, wherein, The thickness of the organic-inorganic hybrid layer is 1μm-3μm.

13. The metal or alloy article according to any one of claims 1-4, 6-10, and 12, wherein, The metal is aluminum or iron, and the alloy is aluminum alloy or stainless steel.

14. The metal or alloy article according to any one of claims 1-4, 6-10, and 12, wherein, The thickness of the anodic oxide layer is 2μm-10μm.

15. The metal or alloy article according to claim 14, wherein, The thickness of the anodic oxide layer is 4μm-7μm.

16. The metal or alloy article according to claim 15, wherein, The metal or alloy product is an exterior decorative item.

17. The metal or alloy article according to claim 16, wherein, The exterior trim items mentioned are exterior trim items for automobiles.

18. A surface treatment method for forming the organic-inorganic hybrid layer on the surface of the anodic oxide layer of a metal or alloy article according to any one of claims 1-17.

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