Surface treatment method for metal or alloy, and metal or alloy product

Abstract

Provided in the present invention are a surface treatment method for a metal or an alloy, and a metal or alloy product. The surface treatment method for a metal or an alloy comprises: forming an organic-inorganic hybrid layer on a surface of an anodic oxidation layer located on at least one surface of a metal or an alloy, wherein the organic-inorganic hybrid layer contains silicon dioxide as a main component, and also contains carbon-containing groups that fill in a spatial network structure formed by the silicon dioxide. At least one surface of the metal or alloy product has an anodic oxidation layer and an organic-inorganic hybrid layer, wherein the organic-inorganic hybrid layer contains silicon dioxide as a main component, and carbon-containing groups that function as a filling in silicon dioxide. In the technical solution provided in the present invention, by forming the organic-inorganic hybrid layer on a surface of the anodic oxidation layer, good corrosion resistance, extremely high hardness and good car washing resistance can be provided, and the requirements of all automotive original equipment manufacturers in the current market can be met.

Description

Surface treatment method of metal or alloy and metal or alloy product

[0001] Cross-reference information

[0002] This application claims priority to the Chinese patent application filed with the China Patent Office on September 15, 2023, with application number 202311191391.5 and invention name “A surface treatment method for metal or alloy and metal or alloy product”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The invention relates to a surface treatment method for metal or alloy and a metal or alloy product, belonging to the technical field of metal and alloy treatment. Background Art

[0004] Aluminum alloy trim strips, due to their unique metallic surface texture and low material density, are increasingly popular in automotive exterior trim, gaining popularity among vehicle owners, especially high-end customers. Due to their material properties, aluminum alloy trim strips cannot be used directly as automotive exterior trim and require surface treatment before use. This treatment allows for a more diverse and personalized appearance, while significantly improving surface hardness and corrosion resistance. Common surface treatments for aluminum alloy trim strips include anodizing, baking varnish, and powder coating.

[0005] As automotive exterior trim, maintaining its decorative effect over a wide range of operating conditions is a fundamental requirement. Currently, after anodizing, aluminum alloy surfaces undergo a conventional chemical sealing process, significantly improving their surface hardness and corrosion resistance, meeting the needs of a significant portion of customers. However, with the increasing demands of high-end customers for decorative parts, particularly with the use of strong alkaline car washes and automatic car washes, traditional anodized products using a pH 12.5 or pH 13.0 process are susceptible to corrosion and scratching, resulting in surface tarnish, whitening, and changes, thus losing their decorative effect.

[0006] To improve corrosion resistance, especially to meet alkali resistance requirements above pH 13.5, anodic electrophoresis 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 the customer, its low hardness makes it inadequate for the stringent car wash resistance test. For the manufacturer, precisely because it is a highly corrosion-resistant organic coating, significant costs are incurred in stripping and reworking the product and the hangers.

[0007] Summary of the Invention

[0008] In order to solve the above technical problems, the purpose of the present invention is to provide a surface treatment method for metals or alloys and metal or alloy products, which can meet the corrosion resistance and car wash resistance requirements of exterior trim products by forming an organic-inorganic hybrid layer on the surface of the anodized layer, while reducing the manufacturing cost of the product.

[0009] To solve the above technical problems, the present invention first provides a surface treatment method for a metal or alloy, which is to form an organic-inorganic hybrid layer on the surface of an anodic oxide layer on at least one surface of the metal or alloy;

[0010] The organic-inorganic hybrid layer is mainly composed of silicon dioxide and contains carbon-containing groups filling the space between the network structures formed by silicon dioxide.

[0011] The present invention also provides a metal or alloy product, at least one surface of which has 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;

[0012] The organic-inorganic hybrid layer is mainly composed of silicon dioxide and contains carbon-containing groups filling the space between the network structures formed by silicon dioxide.

[0013] According to a specific embodiment of the present invention, preferably, the carbon-containing group includes one or a combination of two or more of epoxy, alkyl, alkenyl, alkynyl, and aryl, more preferably epoxy and / or alkyl.

[0014] According to a specific embodiment of the present invention, the present invention is based on an anodic oxide layer as a substrate, and an organic-inorganic hybrid layer is formed thereon. The provided organic-inorganic hybrid layer comprises a main structure with silicon dioxide as the main component. Preferably, the mass ratio of Si element to C element in the organic-inorganic hybrid layer is 0.33-4.3. The present invention has found that by controlling the ratio of silicon-containing components and carbon-containing components in the organic-inorganic hybrid layer within the above range: on the one hand, the content of silicon dioxide can be kept within a suitable range, which can avoid the problem of poor film formation or poor film forming during the construction process caused by excessive silicon dioxide content, and can avoid quality problems such as easy cracking of the film layer; on the other hand, the content of carbon-containing groups can be kept within a suitable range, which can avoid the adverse effect of excessive carbon-containing groups filling the main structure of silicon dioxide on the hardness of the film layer. The organic-inorganic hybrid layer thus obtained has excellent corrosion resistance, extremely high hardness and scratch resistance, and can have the characteristics of easy film formation and not easy cracking while having extremely high hardness. The mass ratio of Si to C in the organic-inorganic hybrid layer is more preferably 0.42-3.7, and further preferably 0.58-2.6. Within the mass ratio range of Si to C provided by the present invention, the mass ratio of the organic-inorganic hybrid layer can be controlled as needed, for example, to 0.42-1.9, 0.58-1.2, 2.6-3.7, etc.

[0015] According to a specific embodiment of the present invention, preferably, the organic-inorganic hybrid layer is formed of an oligomer generated by dehydration condensation of two or more organooxysilanes (containing alkoxy, aryloxy, acyloxy and / or alkylcarbonyl groups).

[0016] 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.

[0017] 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 an epoxy group includes one or more of 3-(2,3-epoxypropyloxy)propyltrimethoxysilane, 3-[(2,3)-epoxypropyloxy]propylmethyldimethoxysilane, 3-(2,3-epoxypropyloxy)propyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, etc.

[0018] According to a specific embodiment of the present invention, preferably, at least one of the two or more organooxysilanes that form the oligomer does not contain an epoxy group. More preferably, the organooxysilane that does not contain an epoxy group comprises a general formula R a SiX (4-a) In the compound shown, a is 0-3, R represents a non-hydrolyzable group selected from alkyl, alkenyl, alkynyl, and aryl groups, and X represents a hydrolyzable group selected from alkoxy, aryloxy, acyloxy, and alkylcarbonyl groups. Specifically, the epoxy-free organooxysilane includes one or a combination of two or more of methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraacetylsilane, methylphenyldimethoxysilane, dimethoxydiacetoxysilane, diethyldiacetoxysilane, di-tert-butoxydiacetoxysilane, diethoxydiphenylsilane, and trimethylphenoxysilane.

[0019] The present invention preferably uses at least one epoxy-containing organooxysilane and at least one epoxy-free organooxysilane to generate oligomers. This combination can bring the following advantages: 1. The epoxy group can improve the density of the coating, thereby improving the salt spray resistance and alkali resistance. At the same time, the epoxy group can also make the coating more tightly bonded to the anodized surface after immersion in 80°C-98°C water for 1-10 minutes. Actual production has found that if the anodized layer is not immersed in 80°C-98°C water, the workpiece is easily scratched by hands, gloves or other items that contact the workpiece during the transfer process, thereby affecting the aesthetic appearance. Experiments have shown that by introducing an epoxy-containing organooxysilane and controlling its content in the system, the coating can be more tightly bonded to the anodized surface after hot water immersion, thereby improving the corrosion resistance of the product; 2. Adding at least one epoxy-free organooxysilane can provide a basic film structure of silicon dioxide, ensuring the key properties of the coating, such as high hardness.

[0020] 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 element to C element 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 element to C element 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.

[0021] According to a specific embodiment of the present invention, preferably, the organic-inorganic hybrid layer is prepared by coating, for example, common coating methods such as dip coating, spray coating, roller coating, brush coating and spin coating.

[0022] According to a specific embodiment of the present invention, preferably, the metal is aluminum or iron, and the alloy is aluminum alloy or stainless steel.

[0023] According to a specific embodiment of the present invention, preferably, the thickness of the anodized layer is 2 μm-10 μm, more preferably 4 μm-7 μm.

[0024] According to a specific embodiment of the present invention, the anodized film layer can be obtained through a conventional process, and after the anodized layer is obtained, it is first immersed in 80℃-98℃ water for 1-10 minutes. In actual production, after anodizing, the workpiece is transferred from the oxidation line tooling to the spraying line tooling. If the anodized layer is not immersed in 80℃-98℃ water, the workpiece is very likely to be scratched by hands, gloves or other items that come into contact with the workpiece during the transfer process, thereby affecting the appearance of the appearance; by immersing in 80℃-98℃ water, on the one hand, the residual acid in the pores of the anodized 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 more convenient for production operation during the transfer process.

[0025] According to a specific embodiment of the present invention, preferably, the metal or alloy product provided by the present invention is an exterior decorative accessory.

[0026] According to a specific embodiment of the present invention, preferably, the exterior decoration product is a high-hardness, scratch-resistant aluminum alloy exterior decoration product.

[0027] The corrosion resistance of the aluminum alloy exterior trim product provided by the present invention can meet the following requirements: resistance to immersion in acid solution with pH = 1.0 for 10 minutes, the better technical solution can reach 1 hour, and the further preferred technical solution can reach 24 hours; resistance to immersion in alkaline solution with pH = 13.5 for 10 minutes, the better technical solution can reach 1 hour, and the further preferred technical solution can reach 2 hours.

[0028] The surface pencil hardness of the aluminum alloy exterior decoration product provided by the present invention is greater than 5H, and more preferably the pencil hardness is greater than 6H.

[0029] The car wash resistance of the aluminum alloy exterior trim product provided by the present invention can meet the following requirements: using the car wash resistance test in the DIN EN ISO 20566 (2013) standard, the 60° gloss retention rate is greater than 90%, and more preferably 95%.

[0030] According to a specific embodiment of the present invention, preferably, the exterior trim is an exterior trim of an automobile.

[0031] The technical solution provided by the present invention can provide excellent corrosion resistance, extremely high hardness, and exceptional car wash resistance by forming an organic-inorganic hybrid layer on the surface of the anodized layer, which can meet the requirements of all automobile OEMs currently on the market. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] FIG1 is a schematic diagram of a specific implementation example of the high-hardness, scratch-resistant aluminum alloy exterior trim product provided by the present invention.

[0033] FIG2 shows the energy spectrum test results of the first organic-inorganic hybrid layer.

[0034] FIG3 shows the energy spectrum test results of the second organic-inorganic hybrid layer.

[0035] Figure 4 shows the film cracking of organic-inorganic hybrid layers with different Si / C mass ratios.

[0036] Figure 5 shows the appearance of organic-inorganic hybrid layers with different Si / C mass ratios.

[0037] Figure 6 shows the test results of car wash tests for different products. DETAILED DESCRIPTION

[0038] In order to have a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be understood as limiting the scope of implementation of the present invention.

[0039] The structure of a specific embodiment of the high-hardness, scratch-resistant aluminum alloy exterior trim provided by the present invention is shown in Figure 1. The aluminum alloy exterior trim comprises an aluminum substrate 101, with anodized layers 201 and 202 provided on both sides thereof, and organic-inorganic hybrid layers 301 and 302 provided on the surfaces of the two anodized layers 201 and 202, respectively.

[0040] Example 1

[0041] An organic-inorganic hybrid layer with different Si / C mass ratios was prepared on the surface of an aluminum alloy substrate by coating, wherein:

[0042] (1) The first organic-inorganic hybrid layer:

[0043] The first organic-inorganic hybrid layer is formed by oligomers generated by dehydration condensation of organooxysilanes. The organooxysilanes used are 3-(2,3-epoxypropyloxy)propyltrimethoxysilane and methyltrimethoxysilane, with a mass ratio of 1.74. Methanol and ethanol are formed during the hydrolysis of silane. After heating and curing, the methanol and ethanol will evaporate from the system, which is equivalent to decarbonization.

[0044] The Si:C mass ratio of the first organic-inorganic hybrid layer is 0.67, and the energy spectrum is shown in FIG2 ;

[0045] The thickness of the first organic-inorganic hybrid layer is 3 μm-5 μm.

[0046] (2) The second organic-inorganic hybrid layer:

[0047] The second organic-inorganic hybrid layer is formed by oligomers generated by dehydration condensation of organooxysilane, and the organooxysilane used is 3-(2,3-epoxypropyloxy)propyltriethoxysilane and tetraethoxysilane, and the mass ratio of the two is 0.16;

[0048] The Si:C mass ratio of the second organic-inorganic hybrid layer is 3.66, and the energy spectrum is shown in FIG3 ;

[0049] The thickness of the second organic-inorganic hybrid layer is 0.5 μm-1.5 μm.

[0050] As can be seen from Figure 2, the Si:C ratio in the first organic-inorganic hybrid layer is 0.67, and the organic content is high. While ensuring that the film quality meets the product appearance requirements, the film thickness can be made thicker.

[0051] As can be seen from Figure 3: the Si:C ratio in the second organic-inorganic hybrid layer is 3.66, and the organic part is much reduced compared to the first organic-inorganic hybrid layer. While ensuring 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 signal of the Al element on the substrate.

[0052] The above organic-inorganic hybrid layer was subjected to pencil hardness, acid resistance, alkali resistance and other tests. Among them, the acid resistance test and alkali resistance test were carried out in the following ways:

[0053] Under standard conditions, aluminum alloy parts with an organic-inorganic hybrid layer on their surfaces are immersed in acid or alkali solutions of specific pH values. During this process, 30mm-50mm test pieces are ensured to be immersed in the test liquid. Samples are taken out for observation at regular intervals. If there is no bubbling, peeling, or other undesirable phenomena on the substrate surface, the sample is qualified and the test is continued. The duration of the last qualified experiment is recorded as the acid or alkali resistance duration.

[0054] The test results are shown in Table 1 below:

[0055] Table 1

[0056] It can be seen from the results recorded in Table 1 that 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 the aluminum alloy substrate.

[0057] Example 2

[0058] Organic-inorganic hybrid layers with different Si / C mass ratios were prepared on the surface of the aluminum alloy substrate by coating to observe the film cracking of the coating. The test results are shown in Figure 4:

[0059] When the Si:C mass ratio in the coating is too high, especially when Si:C>10 or above, it is difficult to form a film. Even if a film is formed, it is very easy to crack when the coating is cured. As shown in Figure 4 (a), the third organic-inorganic hybrid layer is formed by oligomers generated by dehydration condensation of organooxysilane. The organooxysilanes used are 3-(2,3-epoxypropyloxy)propyltrimethoxysilane and tetramethoxysilane, and the ratio of the two is 0.05. The Si:C mass ratio of the third organic-inorganic hybrid layer is 12.35. The front film layer is completely cracked, and the film thickness cannot be tested.

[0060] When the Si:C mass ratio in the coating is reduced to a range of >5, cracks will still appear in local locations of the product (especially where the film thickness is relatively thick during spraying due to the product structure). As shown in Figure 4 (b), the fourth organic-inorganic hybrid layer is formed by oligomers generated by dehydration condensation of organooxysilane. The organooxysilanes used are 3-(2,3-epoxypropyloxy)propyltrimethoxysilane and tetramethoxysilane, and the ratio of the two is 0.1. The Si:C mass ratio of the fourth organic-inorganic hybrid layer is 6.28. The film thickness is between 0.8μm and 1.2μm in normal locations without film cracks, and between 1.6μm and 2.1μm in locations with cracks.

[0061] When the Si:C mass ratio in the coating is within the appropriate range required by the present invention (Si:C=0.33-4.3), appearance problems such as cracking can be avoided, and a product with excellent appearance can be obtained. As shown in Figure 4 (c), the fifth organic-inorganic hybrid layer is formed by oligomers generated by dehydration condensation of organic oxysilane. The organic oxysilanes used are 3-(2,3-epoxypropoxy)propyltrimethoxysilane and tetramethoxysilane, and the ratio of the two is 2.2. The Si:C mass ratio of the fifth organic-inorganic hybrid layer is 0.67, and its film thickness is between 3μm-5μm.

[0062] Example 3

[0063] Organic-inorganic hybrid layers with different Si / C mass ratios were prepared on the surface of the aluminum alloy substrate by coating to observe the appearance of the coating:

[0064] Figure 5 shows the appearance of organic-inorganic hybrid layers with different Si / C mass ratios under a stripe inspection light. The difference in product appearance quality can be seen from the reflection of the light tube on the product.

[0065] Figure 5 (e) shows the appearance of the product without coating on the surface, with light and shadow diverging;

[0066] Figures (f) and (g) in Figure 5 show the appearance of the product surface coated with an organic-inorganic hybrid layer, where:

[0067] The sixth organic-inorganic hybrid layer in FIG5(f) is formed by oligomers generated by dehydration condensation of organooxysilane. The organooxysilanes used are 3-(2,3-epoxypropyloxy)propyltrimethoxysilane and tetramethoxysilane, and the ratio of the two is 0.28. The Si:C mass ratio of the sixth organic-inorganic hybrid layer is 2.6, and the film thickness is between 2.3μm and 2.6μm. As can be seen from FIG5(f), the light and shadow of the lamp tube are clear, and the appearance of the coating is excellent.

[0068] The seventh organic-inorganic hybrid layer in Figure 5 (g) is formed by oligomers generated by dehydration condensation of organooxysilane. The organooxysilanes used are 3-(2,3-epoxypropoxy)propyltrimethoxysilane and methyltrimethoxysilane, and the ratio of the two is 5. The Si:C mass ratio of the seventh organic-inorganic hybrid layer is 0.4, and the film thickness is between 3.4μm and 4.2μm. It can be seen from Figure 5 (g) that the orange peel texture is serious under the light and shadow of the lamp tube, and the appearance effect is poor, which cannot meet the requirements of high-end customers for external light decorative parts.

[0069] Example 4

[0070] Organic-inorganic hybrid layers with different Si / C mass ratios were prepared on the surface of the aluminum alloy substrate by coating to conduct car wash tests. The test results are shown in Table 2:

[0071] FIG6 shows the appearance after testing according to the car wash resistance test in the DIN EN ISO 20566 (2013) standard;

[0072] Figure 6 (h) shows a product produced using the traditional pH = 13.0 process. It is sealed with Ni and silicate, and has no coating on the surface. The outermost layer is an anodic oxide film, which has high hardness and is scratch-resistant. Figure 6 (h) shows that only slight scratches remain on the surface after the car wash test. However, the product fails the alkali resistance test after the car wash test.

[0073] Figure 6 (i) shows a product processed by anodic electrophoresis at pH 13.5. Electrophoresis forms an acrylic resin coating on the surface of the anodic oxide layer. However, this coating has poor hardness. Figure 6 (i) shows severe scratches on the surface after the car wash test. The scratched coating even has a rainbow sheen when viewed from the side, which is unacceptable for exterior decorative products.

[0074] Figure 6 (j) shows a product of the present invention, with the first organic-inorganic hybrid layer of Example 1 applied to its surface. This first organic-inorganic hybrid layer has a Si:C mass ratio of 0.67 and a thickness between 3 and 5 μm. Figure 6 (j) shows only minor scratches on the surface after the car wash test, and the product still meets performance requirements, such as alkali resistance.

[0075] Table 2 Car wash test data of different products

[0076] Test method:

[0077] 1) Content: The Si / C mass ratio in the organic-inorganic hybrid layer was measured using SEM & EDS (electron microscope and energy dispersive spectrometer, model: Zeiss Super 55).

[0078] 2) Film thickness: The cross-section of the organic-inorganic hybrid layer was observed using a SEM & EDS (electron microscope and energy dispersive spectrometer, model: Zeiss Super 55). The film thickness was accurately measured on the obtained cross-sectional image to obtain the film thickness data.

[0079] 3) Car wash test: The glossiness of the test sample was measured after 10 car wash cycles according to the car wash resistance test in DIN EN ISO 20566 (2013).

[0080] 4) Gloss: Use a gloss tester (model: BYK4586) to measure the gloss data of the test sample at an angle of 60°.

[0081] 5) Alkali resistance test: Under room temperature conditions, a. The traditional pH 13.0 process product was immersed in an alkaline solution with a pH of 13.0 for 10 minutes, and the surface corrosion was observed. Corrosion and whitening were not allowed to occur. b. The anodic electrophoresis pH 13.5 process product and the product of the present invention were immersed in an alkaline solution with a pH of 13.5 for 10 minutes, and the surface corrosion was observed. Corrosion and whitening were not allowed to occur. In the alkali resistance test, the occurrence of corrosion and whitening was deemed unqualified, and the absence of corrosion and whitening was deemed qualified. Preparation of pH = 13.0 alkaline solution: 4.0g NaOH, 4.64g Na3PO4·12H2O, and 0.33g NaCl were dissolved in 1L deionized water. Preparation of pH = 13.5 alkaline solution: 12.7g NaOH, 4.64g Na3PO4·12H2O, and 0.33g NaCl were dissolved in 1L deionized water.

Claims

1. A method for surface treatment of a metal or alloy, which comprises forming an organic-inorganic hybrid layer on the surface of an anodic oxide layer on at least one surface of the metal or alloy; in, The organic-inorganic hybrid layer is mainly composed of silicon dioxide and contains carbon-containing groups filled in the space network structure formed by silicon dioxide.

2. The surface treatment method according to claim 1, wherein: The carbon-containing group includes one or a combination of two or more of an epoxy group, an alkyl group, an alkenyl group, an alkynyl group, and an aryl group.

3. The surface treatment method according to claim 2, wherein: The carbon-containing group is an epoxy group and / or an alkyl group.

4. The surface treatment method according to claim 1, wherein: The mass ratio of Si element to C element in the organic-inorganic hybrid layer is 0.33-4.

3.

5. The surface treatment method according to claim 4, wherein: The mass ratio of Si element to C element in the organic-inorganic hybrid layer is 0.42-3.

7.

6. The surface treatment method according to claim 5, wherein: The mass ratio of Si element to C element in the organic-inorganic hybrid layer is 0.58-2.

6.

7. The surface treatment method according to any one of claims 1 to 6, wherein: The organic-inorganic hybrid layer is formed of an oligomer generated by dehydration condensation of two or more organooxysilanes.

8. The surface treatment method according to claim 7, wherein: At least one organooxysilane contains epoxy groups.

9. The surface treatment method according to claim 7 or 8, wherein: The at least one organooxysilane does not contain epoxy groups.

10. The surface treatment method according to any one of claims 7 to 9, wherein: The organooxysilane includes at least one of dialkoxysilanes, trialkoxysilanes and tetraalkoxysilanes, or a combination of two or more thereof.

11. The surface treatment method according to claim 8, wherein: The epoxy-containing organooxysilane includes one or a combination of two or more of 3-(2,3-epoxypropyloxy)propyltrimethoxysilane, 3-[(2,3)-epoxypropyloxy]propylmethyldimethoxysilane, 3-(2,3-epoxypropyloxy)propyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane.

12. The surface treatment method according to claim 9, wherein: The epoxy-free organooxysilane includes the general formula R a SiX (4-a) The compound shown, wherein a is 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.

13. The surface treatment method according to claim 12, wherein: The epoxy-free organooxysilane includes one or a combination of two or more of methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraacetylsilane, methylphenyldimethoxysilane, dimethoxydiacetoxysilane, diethyldiacetoxysilane, di-tert-butoxydiacetoxysilane, diethoxydiphenylsilane and trimethylphenoxysilane.

14. The surface treatment method according to any one of claims 1 to 13, wherein: The thickness of the organic-inorganic hybrid layer is 0.5 μm-5 μm.

15. The surface treatment method according to claim 14, wherein: The thickness of the organic-inorganic hybrid layer is 1 μm-3 μm.

16. The surface treatment method according to any one of claims 1 to 15, wherein: The metal is aluminum or iron, and the alloy is aluminum alloy or stainless steel.

17. The surface treatment method according to any one of claims 1 to 16, wherein: The thickness of the anodized layer is 2 μm-10 μm.

18. The surface treatment method according to claim 17, wherein: The thickness of the anodized layer is 4 μm-7 μm.

19. A metal or alloy product, at least one surface of which has an anodized layer and an organic-inorganic hybrid layer, wherein: The organic-inorganic hybrid layer is formed on the surface of the anodized layer; The organic-inorganic hybrid layer is mainly composed of silicon dioxide and contains carbon-containing groups filled in the space network structure formed by silicon dioxide.

20. The metal or alloy product according to claim 19, wherein: The carbon-containing group includes one or a combination of two or more of an epoxy group, an alkyl group, an alkenyl group, an alkynyl group, and an aryl group.

21. The metal or alloy product according to claim 20, wherein: The carbon-containing group is an epoxy group and / or an alkyl group.

22. The metal or alloy product according to claim 19 or 20, wherein: The mass ratio of Si element to C element in the organic-inorganic hybrid layer is 0.33-4.

3.

23. The metal or alloy product according to claim 22, wherein: The mass ratio of Si element to C element in the organic-inorganic hybrid layer is 0.42-3.

7.

24. The metal or alloy product according to claim 23, wherein: The mass ratio of Si element to C element in the organic-inorganic hybrid layer is 0.58-2.

6.

25. The metal or alloy product according to any one of claims 19 to 24, wherein: The organic-inorganic hybrid layer is formed of an oligomer generated by dehydration condensation of two or more organooxysilanes.

26. The metal or alloy product according to claim 25, wherein: At least one organooxysilane contains epoxy groups.

27. The metal or alloy product according to claim 25 or 26, wherein: The at least one organooxysilane does not contain epoxy groups.

28. The metal or alloy product according to any one of claims 25 to 27, wherein: The organooxysilane includes at least one of dialkoxysilanes, trialkoxysilanes and tetraalkoxysilanes, or a combination of two or more thereof.

29. The metal or alloy product according to claim 26, wherein: The epoxy-containing organooxysilane includes one or a combination of two or more of 3-(2,3-epoxypropyloxy)propyltrimethoxysilane, 3-[(2,3)-epoxypropyloxy]propylmethyldimethoxysilane, 3-(2,3-epoxypropyloxy)propyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane.

30. The metal or alloy article according to claim 27, wherein: The epoxy-free organooxysilane includes the general formula R a SiX (4-a) The compound shown, wherein a is 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.

31. The metal or alloy product according to claim 30, wherein: The epoxy-free organooxysilane includes one or a combination of two or more of methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraacetylsilane, methylphenyldimethoxysilane, dimethoxydiacetoxysilane, diethyldiacetoxysilane, di-tert-butoxydiacetoxysilane, diethoxydiphenylsilane and trimethylphenoxysilane.

32. The metal or alloy product according to any one of claims 19 to 31, wherein: The thickness of the organic-inorganic hybrid layer is 0.5 μm-5 μm.

33. The metal or alloy product according to claim 32, wherein: The thickness of the organic-inorganic hybrid layer is 1 μm-3 μm.

34. The metal or alloy product according to any one of claims 19 to 33, wherein: The metal is aluminum or iron, and the alloy is aluminum alloy or stainless steel.

35. The metal or alloy product according to any one of claims 19 to 34, wherein: The thickness of the anodized layer is 2 μm-10 μm.

36. The metal or alloy article according to claim 35, wherein: The thickness of the anodized layer is 4 μm-7 μm.

37. The metal or alloy product according to any one of claims 19 to 36, wherein: The metal or alloy product is an exterior decoration.

38. The metal or alloy product according to claim 37, wherein: The exterior trim is an exterior trim of a car.

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