Coating composition, coating, preparation method of coating and part for vehicle steering system

Abstract

The invention provides a coating composition, a coating, a preparation method and a part for a vehicle steering system.The coating composition is prepared from, by weight, 10-20 parts of nano ceramic microbeads and 35-50 parts of binder, the binder comprises modified polyacrylate resin and epoxy resin, the weight ratio of the modified polyacrylate resin to the epoxy resin is (40-50): (5-8), and the weight ratio of the modified polyacrylate resin to the epoxy resin is (40-50): (5-8). The modified polyacrylate resin contains an epoxy group and a C3-10 chain alkyl group substituted by a fluorine atom. According to the scheme, the nano ceramic microbeads, the modified polyacrylate resin and the epoxy resin interact to generate a composite effect, so that the single performance of the coating is improved, and synergistic optimization is realized in three dimensions of corrosion resistance, weather resistance and high mechanical strength; the problem that a traditional coating is insufficient in corrosion resistance, weather resistance and mechanical strength is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to a coating composition, a coating and a preparation method thereof, and components for a vehicle steering system. Background Art

[0002] In the modern automotive industry, improving the durability and protection of vehicles, especially off-road vehicles, is crucial to ensuring performance stability and safety. The steering system, as the core component responsible for directional control, has extremely high requirements for corrosion resistance, weather resistance, and mechanical strength.

[0003] Traditional coating processes used in the existing technology to protect steering system components, such as solvent-based or water-dispersible coatings, have many limitations: First, the protective coatings formed by these coatings often have a single function and cannot simultaneously meet the requirements of corrosion resistance, weather resistance and high mechanical strength. For example, some coatings perform well in terms of weather resistance but are insufficient in terms of corrosion resistance, and vice versa; second, in order to achieve the ideal protective effect, multi-layer coating is usually required, the process is complex, the coating is thick, and the protection period is limited. Rust, gloss loss, powdering, discoloration and other problems often occur after one to three years of use. This not only increases production costs, but also reduces the performance durability of components.

[0004] Currently, no effective solution has been proposed to the problem that coatings in existing technologies are difficult to simultaneously meet the requirements of corrosion resistance, weather resistance and high mechanical strength. Summary of the Invention

[0005] The main purpose of the present invention is to provide a coating composition, a coating and a preparation method, and components for a vehicle steering system, so as to solve the problem that coatings in the prior art are difficult to simultaneously meet the requirements of corrosion resistance, weather resistance and high mechanical strength.

[0006] To achieve the above object, according to one aspect of the present invention, a coating composition is provided, which comprises, by weight, 10 to 20 parts of nano-ceramic microbeads and 35 to 50 parts of a binder, wherein the binder comprises a modified polyacrylate resin and an epoxy resin, wherein the weight ratio of the modified polyacrylate resin to the epoxy resin is (40 to 50):(5 to 8), and the modified polyacrylate resin contains an epoxy group and a chain alkyl group with 3 to 10 carbon atoms substituted by a fluorine atom.

[0007] Furthermore, the coating composition further comprises 20 to 30 parts of other additives, including pigments, and no inorganic metal powder is added to the other additives.

[0008] Furthermore, other additives also include a silane coupling agent, and the weight ratio of the silane coupling agent to the nano-ceramic microbeads is (5-10): (30-45).

[0009] Furthermore, the coating composition also includes a curing agent, which is used to cure the mixture of the coating composition.

[0010] Furthermore, it is preferred that the curing agent is a polyamide curing agent.

[0011] Furthermore, the weight ratio of the mixture of the nano-ceramic microbeads and the binder to the polyamide curing agent is (1-2): (1-2.5).

[0012] According to another aspect of the present invention, a coating is provided. The coating is prepared using raw materials including the above-mentioned coating composition.

[0013] According to another aspect of the present invention, a method for preparing a coating is provided, comprising the following steps: mixing a mixture of nano-ceramic microbeads and a binder with a curing agent to obtain a preliminary coating; and curing the preliminary coating to obtain a final coating.

[0014] Furthermore, the curing treatment temperature is 20-50° C., and the curing time is 0.5-24 h.

[0015] According to another aspect of the present invention, a component for a vehicle steering system is provided. The component for a vehicle steering system is coated with a coating, and the coating is the above-mentioned coating, or the coating is prepared by the above-mentioned preparation method.

[0016] By applying the technical solution of the present invention, the nano-ceramic microbeads have high hardness and stable chemical properties, which can improve the wear resistance and impact resistance of the coating, that is, improve the mechanical strength of the coating; the epoxy group in the modified polyacrylate resin strengthens the adhesion between the resin and the substrate, thereby improving the adhesion of the coating; the chain alkyl group with 3 to 10 carbon atoms replaced by fluorine atoms makes the resin hydrophobic and oleophobic, enhances the coating's ability to repel water and corrosive media, and thus improves the corrosion resistance of the coating; the epoxy resin has antioxidant and temperature stability, can effectively resist oxidation in the atmosphere, ensures that the coating is not easy to age and deteriorate during long-term outdoor use, and can maintain its physical and chemical properties within a wide temperature range, so that the coating can still maintain good stability in an alternating hot and cold environment, is not prone to cracking or peeling, and improves the weather resistance of the coating. In the above scheme, the interaction between nano-ceramic microbeads, modified polyacrylate resin and epoxy resin produces a composite effect, which not only improves the single performance of the coating, but also achieves synergistic optimization in the three dimensions of corrosion resistance, weather resistance and high mechanical strength, effectively solving the problems of insufficient corrosion resistance, weather resistance and mechanical strength of traditional coatings. DETAILED DESCRIPTION

[0017] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the embodiments.

[0018] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0019] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0020] Now, exemplary embodiments according to the present application will be described in more detail. However, these exemplary embodiments may be implemented in a variety of different forms and should not be construed as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of this application thorough and complete and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art.

[0021] As analyzed in the background art, the gold coating in the prior art is difficult to simultaneously meet the requirements of corrosion resistance, weather resistance and high mechanical strength. To solve this problem, the present invention provides a coating composition, a coating and a preparation method, and components for vehicle steering systems.

[0022] In a typical embodiment of the present application, a coating composition is provided, which includes, by weight, 10 to 20 parts of nano-ceramic microbeads and 35 to 50 parts of a binder, wherein the binder includes a modified polyacrylate resin and an epoxy resin, and the weight ratio of the modified polyacrylate resin to the epoxy resin is (40 to 50): (5 to 8), and the modified polyacrylate resin contains an epoxy group and a chain alkyl group with 3 to 10 carbon atoms substituted by a fluorine atom.

[0023] In the embodiments of the present application, the nano-ceramic microbeads have high hardness and stable chemical properties, which can improve the wear resistance and impact resistance of the coating, that is, improve the mechanical strength of the coating; the epoxy group in the modified polyacrylate resin strengthens the adhesion between the resin and the substrate, thereby improving the adhesion of the coating; the chain alkyl group with 3 to 10 carbon atoms replaced by fluorine atoms makes the resin hydrophobic and oleophobic, enhances the coating's repellency to water and corrosive media, thereby improving the corrosion resistance of the coating; the epoxy resin has antioxidant and temperature stability, can effectively resist oxidation in the atmosphere, ensure that the coating is not easy to age and deteriorate during long-term outdoor use, and can maintain its physical and chemical properties within a wide temperature range, so that the coating can still maintain good stability in a hot and cold alternating environment, is not prone to cracking or peeling, and improves the weather resistance of the coating. In the above scheme, the interaction between nano-ceramic microbeads, modified polyacrylate resin and epoxy resin produces a composite effect, which not only improves the single performance of the coating, but also achieves synergistic optimization in the three dimensions of corrosion resistance, weather resistance and high mechanical strength, effectively solving the problems of insufficient corrosion resistance, weather resistance and mechanical strength of traditional coatings.

[0024] In one embodiment of the present application, the raw materials for preparing the modified polyacrylate resin include a first acrylate monomer and an acrylate prepolymer, the first acrylate monomer contains an epoxy group, the acrylate prepolymer contains a chain alkyl group with 3 to 10 carbon atoms substituted by a fluorine atom, and the double bonds in the first acrylate and the acrylate prepolymer undergo free radical polymerization to form a copolymerized modified polyacrylate resin.

[0025] In one embodiment of the present application, the raw materials for preparing the acrylate prepolymer include a second acrylate monomer, a third acrylate monomer and mercaptoethanol, the second acrylate monomer contains a chain alkyl group with 3 to 10 carbon atoms substituted by a fluorine atom, and the third acrylate monomer contains an isocyanate group.

[0026] In one embodiment of the present application, the first acrylic ester monomer includes glycidyl methacrylate.

[0027] In one embodiment of the present application, the second acrylic acid ester monomer includes at least one of hexafluorobutyl acrylate and hexafluorobutyl methacrylate.

[0028] In one embodiment of the present application, the third acrylic acid ester monomer is isocyanoethyl methacrylate.

[0029] In one embodiment of the present application, the molar ratio of the first acrylate monomer, the second acrylate monomer, and the third acrylate monomer is (2.5-5):(1-2):(0.2-1.4). By regulating the monomer structure and molar ratio in the modified polyacrylate resin, the content of epoxy groups and fluorine-substituted alkyl groups in the modified polyacrylate resin is indirectly regulated to further enhance the synergistic effect of the binder, nano-ceramic microbeads, and other additives, thereby further enhancing the weather resistance of the coating.

[0030] In one embodiment of the present application, the method for preparing the above-mentioned acrylate prepolymer comprises the following steps:

[0031] The second acrylic acid ester monomer and mercaptoethanol are subjected to a first polymerization reaction, and then the third acrylic acid ester monomer is added to carry out a second polymerization reaction.

[0032] It can be understood that in the second polymerization reaction, the hydroxyl groups in the product of the first polymerization reaction that are blocked with mercaptoethanol undergo condensation reaction to form urethane groups.

[0033] In one embodiment of the present application, taking the second acrylic ester monomer as hexafluorobutyl acrylate (HFA) and hexafluorobutyl methacrylate (HFMA) as an example, the preparation method of the acrylic ester prepolymer includes the following steps:

[0034] An acrylate prepolymer is prepared by placing HFA, HFMA, AIBN (azobisisobutyronitrile), and 2-ME in MEK (methyl ethyl ketone) for a first polymerization reaction, followed by the addition of IEM (isocyanatoethyl methacrylate) in the presence of dibutyltin dilaurate for a second polymerization reaction. The mass ratio of HFA, HFMA, 2-ME, and IEM is (1-2):(1-2):(0.1-0.2):(0.3-0.5).

[0035] After the second polymerization reaction is completed, the following purification step is also included: the product of the second polymerization reaction is precipitated with petroleum ether, the precipitate is dissolved with MEK (methyl ethyl ketone), and then precipitated with petroleum ether again; this purification step can be repeated N times, where N is an integer greater than or equal to 1, to wash away unreacted initiator or monomer.

[0036] The first polymerization reaction is carried out at a temperature of 60°C to 80°C for 12 hours to 24 hours, and the second polymerization reaction is carried out at a temperature of 60°C to 70°C for 12 hours to 24 hours.

[0037] In one embodiment of the present application, the preparation method of the modified polyacrylate resin comprises the following steps:

[0038] The acrylic ester prepolymer and the first acrylic ester monomer are subjected to a free radical polymerization reaction in a solvent to prepare a modified polyacrylate resin.

[0039] The mass ratio of the first acrylate to the acrylate prepolymer is (2-5):1. The free radical polymerization reaction is carried out at a temperature of 60°C to 80°C for 5 to 10 hours. The initiator for the free radical polymerization reaction is AIBN (azobisisobutyronitrile), and the solvent is MEK (methyl ethyl ketone).

[0040] In one embodiment of the present application, the nano-ceramic microbeads have a hollow structure.

[0041] Hollow nano-ceramic microbeads, due to their internal cavities, have a lower density than solid microbeads. This significantly reduces the overall weight of a coating for the same volume of microbeads. For applications such as steering system components, reducing coating weight not only helps reduce the vehicle's total load but also improves fuel efficiency. The air or inert gas within the hollow nano-ceramic microbeads acts as a thermal insulator, significantly reducing the coating's thermal conductivity and enhancing its insulation. This is crucial for the thermal stability of steering system components operating in high-temperature environments, effectively protecting the substrate from thermal damage and extending component life. The cavities within the nano-ceramic microbeads reduce stress concentration within the coating, improving its resistance to spalling and further enhancing its corrosion resistance. The hollow nano-ceramic microbeads absorb and buffer the impact of natural factors such as ultraviolet rays, rain, and windblown sand on the coating. The reflection and scattering effects of the microbead walls reduce damage to the coating, thereby improving its weather resistance.

[0042] In a typical embodiment of the present application, the coating composition further comprises 20 to 30 parts of other additives, wherein the other additives include pigments, and no inorganic metal powder is added to the other additives.

[0043] In the embodiments of the present application, the addition of pigments can not only meet the visual aesthetic requirements, but also ensure that the coating has good color stability. The selection of pigments with good weather resistance and corrosion resistance can also prevent color fading caused by ultraviolet radiation or erosion by corrosive media. Mixing metal powder into the coating, especially in a humid environment, can easily form micro-batteries and accelerate the corrosion of the metal substrate. Not adding inorganic metal powder makes the coating more stable and does not weaken the protective effect due to its own internal electrochemical reaction. Not adding inorganic metal powder simplifies the formulation and production process of the coating. The addition of inorganic metal powder often requires special treatment to ensure its dispersion uniformity and stability in the coating. For example, a solvent needs to be added to fully mix and disperse the inorganic metal powder. Removing this complex step makes the coating composition easier to prepare, improves production efficiency, and reduces costs.

[0044] In one embodiment of the present application, other additives further include a silane coupling agent, and the weight ratio of the silane coupling agent to the nano-ceramic microbeads is (5-10): (30-45).

[0045] In an embodiment of the present application, the silane coupling agent molecule has a bifunctional group, wherein a part of the functional group can react with the hydroxyl group or other active groups on the surface of the nano-ceramic microbeads, and the other part forms a chemical bond with the binder. The silane coupling agent builds a bridge between two different materials, strengthens the interfacial bonding force between the nano-ceramic microbeads and the binder, and promotes the integration of the internal structure of the coating. When the weight ratio of the silane coupling agent to the nano-ceramic microbeads is within a specified range, it can promote the uniform dispersion of the nano-ceramic microbeads in the coating system, avoids agglomeration, and makes the coating more uniform and dense. The use of silane coupling agent can simplify the processing technology of the coating. The silane coupling agent can improve the dispersibility and stability of the nano-ceramic microbeads in the coating, reduces additional processing steps and time, thereby improving production efficiency and economy. The addition of silane coupling agent helps to adjust the mechanical properties of the coating so that it, while maintaining high hardness, also has appropriate toughness, avoids brittleness too large and causes the coating to be easily cracked or fall off.

[0046] Preferably, the mass ratio of the silane coupling agent to the nano-ceramic microbeads is (1.5-5): (10-20).

[0047] Preferably, the silane coupling agent is at least one of PSI®-520, PSI®-500, and KH-560.

[0048] In a typical embodiment of the present application, the coating composition further includes a curing agent, and the curing agent is used to cure the mixture of the coating composition.

[0049] In the embodiments of this application, the curing agent promotes the cross-linking reaction of the binder (such as modified polyacrylate resin and epoxy resin) in the coating, significantly shortening the curing time while also forming a denser and stronger three-dimensional network structure. This in turn improves the coating's hardness, impact resistance, and abrasion resistance, making it less susceptible to flaking or breakage under mechanical stress. During the curing process, the curing agent also promotes chemical bonding between the coating and the substrate, enhancing the coating's adhesion and preventing separation or flaking from the substrate under physical or chemical stress.

[0050] It should be noted that the substrate is sprayed using a spray gun, and the mixture of nano-ceramic microbeads and a binder is mixed with a curing agent before the spray gun, that is, the curing agent is set at the front end of the spray gun, and the mixture of nano-ceramic microbeads and a binder is input into the spray gun and mixed with the curing agent before spraying on the substrate to avoid affecting the fluidity of the coating before coating.

[0051] Preferably, the curing agent is a polyamide curing agent.

[0052] When polyamide curing agents react with epoxy resins, they require no external heat source and can cure rapidly at room temperature or even at low temperatures, significantly improving the coating's applicability and production efficiency. When cross-linked with epoxy resins, polyamide curing agents form a flexible cured network structure, which imparts excellent flexibility to the coating. Compared to rigid curing agents, coatings formed with polyamide curing agents are less likely to crack or peel when subjected to impact or bending, enhancing the coating's durability, especially in dynamic load-bearing situations such as vehicle steering system components. During the curing process, polyamide curing agents generate amine groups, which can interact with reactive groups on the metal surface, strengthening chemical bonds and improving the adhesion of the coating to the metal substrate.

[0053] Furthermore, the weight ratio of the mixture of the nano-ceramic microbeads and the binder to the polyamide curing agent is (1-2): (1-2.5).

[0054] In the embodiments of the present application, the contents of the components are proportioned in the above ratios, which can promote effective reactions between the nano-ceramic microbeads, the binder and the polyamide curing agent, ensuring that the coating is thoroughly cured and forming a highly cross-linked network structure.

[0055] According to another specific embodiment of the present application, a coating is provided, which is prepared using raw materials including the above-mentioned coating composition.

[0056] In the embodiments of the present application, the interaction between nano-ceramic microbeads, modified polyacrylate resin and epoxy resin produces a composite effect, which not only improves the single performance of the coating, but also achieves synergistic optimization in the three dimensions of corrosion resistance, weather resistance and high mechanical strength, thereby improving the corrosion resistance, weather resistance and mechanical strength of the coating.

[0057] According to another specific embodiment of the present application, a method for preparing a coating is provided, comprising the following steps:

[0058] Step S1: Mixing the mixture of nano-ceramic microbeads and a binder with a curing agent to obtain a preliminary coating.

[0059] Step S2: curing the preliminary coating to obtain a final coating.

[0060] In the examples of this application, nano-ceramic microbeads provide a physical barrier, while modified polyacrylate resin and epoxy resin form a chemical protective layer. The synergistic effect of these two elements results in a coating with significant advantages in corrosion resistance, weather resistance, and mechanical strength. Further curing of the initial coating accelerates film formation and shortens the production cycle of the workpiece.

[0061] The curing temperature is 20-50°C and the curing time is 0.5-24h.

[0062] The thickness of the coating is 90µm~150µm.

[0063] Before spraying the substrate, the surface of the substrate is sequentially subjected to sandblasting treatment, rust prevention treatment and compressed air cleaning treatment.

[0064] According to another specific embodiment of the present application, a component for a vehicle steering system is provided. The component for a vehicle steering system is coated with a coating. The coating is the above-mentioned coating, or the coating is prepared using the above-mentioned preparation method.

[0065] Among them, components for vehicle steering systems include but are not limited to: steering wheels, steering shafts, steering intermediate shafts, steering oil pipes, steering oil pumps, steering oil tanks, steering knuckle arms, steering tie rods, steering rocker arms, integral steering gears, steering tie rods, steering dampers, etc.

[0066] Example 1

[0067] Preparation of modified polyacrylate resin:

[0068] Step S10: 10 g of hexafluorobutyl acrylate (HFA), 10 g of hexafluorobutyl methacrylate (HFMA), 0.2 g of azobisisobutyronitrile (AIBN), 1.2 g of mercaptoethanol (2-ME), and 40 g of butanone (MEK) were weighed and mixed to form a solution, which was placed in a three-necked flask and polymerized at 80° C. for 24 h. The mixture was then cooled to 70° C., 4.77 g of isocyanoethyl methacrylate (IEM) and 2 drops of dibutyltin dilaurate (DBTDL) were added, and the mixture was reacted at 70° C. for 24 h. After the reaction, the polymer solution was precipitated with petroleum ether (PE), the supernatant was decanted, and the precipitate was dissolved with butanone (MEK), and then precipitated with petroleum ether (PE) again after dissolution. This process was repeated three times. Finally, the precipitate was collected and vacuum-dried to constant mass to obtain acrylate prepolymer FM with a yield of 90%.

[0069] Step S20: Weigh 15 g of the above-prepared acrylic prepolymer FM, 35 g of glycidyl methacrylate (GMA), and 1 g of azobisisobutyronitrile (AIBN), mix them into a solution, and place them in a three-necked flask. Polymerize them at 80° C. for 10 h. After the reaction, precipitate the polymer solution with petroleum ether (PE), remove the supernatant, and dissolve the precipitate with butanone (MEK). After dissolution, precipitate with petroleum ether (PE) again. Repeat this process three times, and collect the precipitate to obtain a modified polyacrylate resin.

[0070] The coating composition was prepared:

[0071] The nano-ceramic hollow microspheres, the binder (the modified polyacrylate resin and epoxy resin), the pigment (carbon black) and the coupling agent were mixed according to the mass ratio in Table 1 to prepare a first mixture.

[0072] Spraying of coatings and parts:

[0073] The metal body surface of the steering system was pre-treated in the following order: sandblasting for 10 min, cleaning with compressed air, coating with an anti-rust polymer film (inositol hexaphosphate), and cleaning with compressed air.

[0074] The first mixture formed by mixing the above and the curing agent are mixed according to the mass ratio in Table 1, and mixed in front of the spray gun. After mixing, the treated workpiece is sprayed.

[0075] After spraying, the coating was cured at room temperature for 0.5 hours to form a coating with a cured thickness of 90 μm, and the parts were obtained.

[0076] Performance testing:

[0077] 1. Conduct neutral salt spray corrosion tests on components in accordance with the standard GB / T 1771-2007 "Paints and varnishes - Determination of resistance to neutral salt spray". Observe the time it takes for the coating to develop red rust products and blistering, which is recorded as the salt spray resistance time. Conduct neutral weathering resistance tests on components in accordance with the standard GB / T 1865-2009 "Paints and varnishes - Artificial weathering and artificial radiation exposure to filtered xenon arc radiation". Observe the time it takes for the coating to develop obvious discoloration and peeling, which is recorded as the weathering resistance time, in accordance with the evaluation standard GB / T 1766-2008 "Paints and varnishes - Rating method for coating aging".

[0078] 2. Adhesion shall be carried out in accordance with GB / T 9286-1998 "Scratch test for paint and varnish films".

[0079] 3. Impact strength is tested in accordance with GB / T 1732-1993 "Determination of impact resistance of paint films". The test steps for stone impact resistance are as follows:

[0080] Step 1000: Connect the stone impact tester to the compressed air pipe, place the coating sample to be tested with the tested surface facing the stone flow outlet of the stone impact tester, fix it on the fixture frame, and tighten it.

[0081] Step 2000: Open the valve of the compressed air conduit and adjust the released air flow through the pressure reducing valve to a pressure of 0.2 MPa as indicated by the pressure gauge.

[0082] Step 3000: Weigh 500 g of angular steel shot and evenly load it into a hopper. The steel shot is gathered by the airflow and sprayed onto the test surface. The compressed air valve is then closed, and the steel shot is collected in a collection hopper.

[0083] Step 4000: Repeat step 3 twice.

[0084] Step 5000: Use a 12-15 cm long tape to completely adhere to the damaged surface and press it tightly (use a plastic scraper or cam to apply pressure). Bend the remaining tail of the tape upwards, and then tear the tape violently in the vertical direction of the test plate to remove the damaged part of the paint film from the coating surface. Finally, continue to compare with the anti-stone chip standard picture to confirm the anti-stone chip level. The anti-stone chip level is represented by an integer from 0 to 10. The smaller the value, the better the anti-stone chip performance.

[0085] 4. The chemical resistance test of the coating is as follows:

[0086] Use engine oil (SG10W / 30) to perform a spot test at 23°C for 16 hours to observe whether the paint film has any changes;

[0087] Use 0.05mol / L sulfuric acid solution at 23℃ for 24 hours to observe whether the paint film has any changes;

[0088] Use 0.1mol / L sodium hydroxide solution and maintain it at 23℃ for 24 hours to observe whether the paint film has any changes.

[0089] 5. Install the parts in the steering system and install them on an off-road vehicle for road testing: After the vehicle has run 50,000 km, check whether the coating surface of the parts has obvious discoloration, peeling, or rust.

[0090] Please see Table 1 for specific test results.

[0091] Example 2

[0092] Example 2 is basically the same as Example 1, except that the ratio of the coating composition is different from that of Example 1.

[0093] Example 3

[0094] Example 3 is basically the same as Example 1, except that the ratio of the coating composition is different from that of Example 1.

[0095] Comparative Example 1

[0096] Comparative Example 1 is substantially the same as Example 1, except that in step S1, hexafluorobutyl acrylate (HFA) and hexafluorobutyl methacrylate (HFMA) are replaced by equal masses of n-butyl acrylate and butyl trifluoromethacrylate, respectively.

[0097] Comparative Example 2

[0098] The coating and parts are prepared as follows:

[0099] The metal body surface of the steering system is pre-treated in the following order: sandblasting for 10 minutes, compressed air cleaning, phosphating and compressed air cleaning.

[0100] An acrylic topcoat was sprayed on the surface of the pre-treated workpiece to form a coating with a thickness of 90 microns to obtain a steering system component.

[0101] The performance test steps are the same as those in Example 1.

[0102] The main components and proportions of the coating compositions in each embodiment and comparative example, as well as the test results of the coatings are shown in Table 1.

[0103] Table 1

[0104]

[0105] It should be noted that: “ / ” means that the condition does not exist.

[0106] For ease of description, spatially relative terms such as "above," "above," "on the upper surface of," and "above" may be used herein to describe the spatial positional relationship of a device or feature to other devices or features. It should be understood that spatially relative terms are intended to encompass different orientations during use or operation. For example, if a device is inverted, a device described as "above" or "above" another device or structure would then be positioned as "below" or "below" the other device or structure. Thus, the exemplary term "above" may include both the orientations of "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used herein should be interpreted accordingly.

[0107] In addition to the above, it should be noted that references to "one embodiment," "another embodiment," "an embodiment," and the like in this specification refer to specific features, structures, or characteristics described in conjunction with that embodiment as included in at least one embodiment generally described in this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in conjunction with any embodiment, it is intended that such feature, structure, or characteristic, when implemented in conjunction with other embodiments, also falls within the scope of the present invention.

[0108] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0109] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A coating composition, characterized in that The coating composition comprises, in parts by weight, 10 to 20 parts of nano-ceramic microbeads and 35 to 50 parts of a binder, wherein the binder comprises a modified polyacrylate resin and an epoxy resin, wherein the weight ratio of the modified polyacrylate resin to the epoxy resin is (40 to 50):(5 to 8), and the modified polyacrylate resin contains an epoxy group and a chain alkyl group having 3 to 10 carbon atoms substituted by a fluorine atom.

2. The coating composition according to claim 1, wherein The coating composition further comprises 20 to 30 parts of other additives, wherein the other additives include pigments, and no inorganic metal powder is added to the other additives.

3. The coating composition according to claim 2, characterized in that The other additives further include a silane coupling agent, and the weight ratio of the silane coupling agent to the nano-ceramic microbeads is (5-10): (30-45).

4. The coating composition according to any one of claims 1 to 3, characterized in that The coating composition further includes a curing agent, which is used to cure the mixture of the coating composition.

5. The coating composition according to claim 4, characterized in that Preferably, the curing agent is a polyamide curing agent.

6. The coating composition according to claim 5, characterized in that The weight ratio of the mixture of the nano-ceramic microbeads and the binder to the polyamide curing agent is (1-2): (1-2.5).

7. A coating, characterized in that The coating is prepared using raw materials comprising the coating composition according to any one of claims 1 to 6.

8. A method for preparing a coating, characterized in that: The following steps are involved: mixing the mixture of nano-ceramic microbeads and a binder with a curing agent to obtain a preliminary coating; The preliminary coating is cured to obtain a final coating.

9. The preparation method according to claim 8, characterized in that The curing treatment temperature is 20-50° C. and the curing time is 0.5-24 hours.

10. A component for a vehicle steering system, the component being coated with a coating, characterized in that: The coating is the coating described in claim 7, or the coating is prepared using the preparation method described in claim 8 or 9.

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