Wear-resistant and corrosion-resistant spraying process for aluminum alloy wheel

Abstract

The invention provides a wear-resistant and corrosion-resistant spraying process for an aluminum alloy wheel. The wear-resistant and corrosion-resistant spraying process comprises the following steps: a) carrying out double sand blasting treatment on the surface of the aluminum alloy wheel; b) carrying out acid pickling and activating treatment on the surface subjected to sand blasting; c) after activating treatment, spraying an epoxy resin composite material containing a hydroxyl functional group on the surface of the aluminum alloy by using a low-temperature plasma auxiliary spraying process; d) after the bottom coating is cured, spraying a ceramic reinforced middle coating; and e) finally, spraying a fluorine-containing polymer and graphene composite material on the intermediate coating as a surface coating, and carrying out high-temperature curing treatment to form a compact protective film. Double sand blasting treatment and a low-temperature plasma auxiliary spraying technology are adopted, so that the wear resistance of the coating is remarkably improved, and the service life of the wheel is prolonged. And through pickling activation and spraying of a high-quality composite material, the corrosion resistance of the aluminum alloy wheel is improved, and corrosion factors in the environment are effectively resisted.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum alloy wheel processing, and specifically to a wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels. Background Art

[0002] Due to its excellent mechanical properties, lightweight characteristics, and good corrosion resistance, aluminum alloy is widely used in the automotive, aerospace, and other industrial fields. In the automotive industry, aluminum alloy wheels are favored for their lightweight design, which can effectively reduce the vehicle's self-weight, improve fuel efficiency, and driving performance. However, during actual use, aluminum alloy wheels are prone to wear and corrosion, especially under harsh environmental conditions, such as the erosion of rainwater, salt spray, and chemical substances. These factors not only affect the appearance of the wheels but may also seriously impact their safety and service life.

[0003] To solve the problems of wear resistance and corrosion resistance of aluminum alloy wheels, researchers and engineers have proposed various surface treatment technologies. Among them, the spraying process is widely used due to its simplicity, high efficiency, and economy. Although traditional spraying technologies can improve the surface properties of aluminum alloy wheels to a certain extent, they often suffer from problems such as poor adhesion, uneven coating thickness, and insufficient wear resistance. Therefore, developing a new spraying process to improve the wear resistance and corrosion resistance of aluminum alloy wheels has become a hot topic in current technical research.

[0004] In recent years, low-temperature plasma-assisted spraying technology has gradually emerged. This technology can effectively improve the adhesion and uniformity of the coating by spraying under low-temperature conditions. At the same time, using epoxy resin composites containing hydroxyl functional groups can enhance the chemical bonding between the coating and the aluminum alloy surface. In addition, ceramic-reinforced intermediate coatings and fluoropolymer and graphene composite surface coatings further improve the wear resistance and corrosion resistance of the coating.

[0005] In summary, the research on the wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels not only has important theoretical significance but also has broad application prospects. Summary of the Invention

[0006] Aiming at the above-mentioned existing technical deficiencies, the purpose of the present invention is to provide a wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels, which improves the wear resistance of the coating and extends the service life of the wheels.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels, comprising the following steps:

[0009] a) Double sandblasting treatment is carried out on the surface of the aluminum alloy wheel. Secondary sandblasting treatment is carried out using coarse-grained and fine-grained alumina particles to remove the oxide scale and improve the surface roughness;

[0010] b) The sandblasted surface is pickled and activated. It is soaked with a mixed acid to remove microscopic surface contaminants and generate a uniform active surface;

[0011] c) After the activation treatment, a low-temperature plasma-assisted spraying process is used to spray an epoxy resin composite containing hydroxyl functional groups on the aluminum alloy surface, so that it forms a chemical bond with the aluminum alloy surface;

[0012] d) After the bottom coating is cured, a ceramic-reinforced intermediate coating is sprayed. The intermediate coating is made of a composite material of nano-alumina and polyurethane-based, and is formed by a multi-layer spraying process. Each coating is controlled at 5-10 microns;

[0013] e) Finally, a composite material of fluoropolymer and graphene is sprayed on the intermediate coating as the top coating, and high-temperature curing treatment is carried out to form a dense protective film.

[0014] Preferably, the epoxy resin composite in the bottom coating includes polyetheramine-based epoxy resin.

[0015] Preferably, the ratio of nano-alumina to polyurethane-based composite material in the ceramic-reinforced intermediate coating is 1:2 to 1:5.

[0016] Preferably, the top coating of the composite material of fluoropolymer and graphene is subjected to superhydrophobic chemical modification treatment, and its contact angle is greater than 140 degrees.

[0017] Preferably, during the spraying process, all coatings are carried out under a nitrogen protection environment to avoid the adsorption of impurities on the coating surface.

[0018] Preferably, during the spraying process, each layer of the intermediate coating is subjected to layer-by-layer curing treatment, the curing temperature is 60 degrees Celsius, and the time is 2 hours.

[0019] Preferably, during the spraying process, the high-temperature curing temperature of the top coating is 120 degrees Celsius, and the time is 3 hours.

[0020] Preferably, during the spraying process, the top coating is polished to improve its surface gloss and appearance quality.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] Improve wear resistance: By adopting double sandblasting treatment and low-temperature plasma-assisted spraying technology, the wear resistance of the coating is significantly improved, and the service life of the wheel is extended.

[0023] Enhanced corrosion resistance: Through pickling activation and spraying of high-quality composite materials, the corrosion resistance of aluminum alloy wheels is improved, effectively resisting corrosive factors in the environment.

[0024] Improve adhesion: The use of epoxy resin composite materials containing hydroxyl functional groups enhances the chemical bonding between the coating and the aluminum alloy surface and reduces the risk of coating peeling.

[0025] Improved coating uniformity: The low-temperature plasma-assisted spraying process ensures uniform coating and helps improve overall surface quality.

[0026] Environmental protection: The coating materials and processes used are relatively environmentally friendly, reducing the emission of harmful substances and meeting the sustainable development requirements of modern manufacturing industry.

[0027] Economic benefits: By improving the wear and corrosion resistance of the wheels, the frequency of maintenance and replacement is reduced, thereby reducing long-term use costs.

[0028] Strong adaptability: This spraying process can be applied to the production and modification of a variety of aluminum alloy wheels, with wide applicability and flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a flowchart of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the accompanying drawings.

[0031] like Figure 1 As shown, a wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels is described in detail below through two embodiments.

[0032] Example 1

[0033] 1. Material Preparation

[0034] Grit blasting particles: coarse and fine grit aluminum oxide particles.

[0035] Pickling solution: mixed acid (such as a mixture of hydrochloric acid and sulfuric acid).

[0036] Primer material: polyetheramine epoxy resin composite material.

[0037] Intermediate coating material: nano-alumina and polyurethane-based composite material (ratio 1:3).

[0038] Top coating material: Fluorine-containing polymer and graphene composite material (after super-hydrophobic chemical modification).

[0039] 2. Process steps

[0040] Sandblasting treatment:

[0041] For the first sandblasting, use coarse-grained alumina particles for 15 minutes to remove the surface scale.

[0042] Subsequently, for the second sandblasting, use fine-grained alumina particles for 10 minutes to increase the surface roughness.

[0043] Pickling activation:

[0044] Immerse the sandblasted wheels in the mixed acid for 30 minutes to remove microscopic contaminants.

[0045] Low-temperature plasma spraying:

[0046] Treat the activated wheels in a cold plasma device and spray an epoxy resin composite containing hydroxyl functional groups to ensure the formation of chemical bonds with the aluminum alloy surface.

[0047] Intermediate coating spraying:

[0048] After the primer coat is cured, use the multi-layer spraying method to spray a composite of nano-alumina and polyurethane-based material, with the thickness of each layer controlled at 5 microns, and cure each layer for 2 hours at a curing temperature of 60 °C.

[0049] Top coating spraying:

[0050] Spray a composite of fluoropolymer and graphene on the intermediate coating and conduct high-temperature curing treatment at a temperature of 120 °C for 3 hours.

[0051] Polishing treatment:

[0052] Finally, polish the top coating to enhance the surface gloss.

[0053] Example 2

[0054] 1. Material preparation

[0055] Sandblasting particles: Coarse-grained (80 mesh) and fine-grained (120 mesh) alumina particles.

[0056] Pickling solution: A mixed solution of concentrated hydrochloric acid and concentrated sulfuric acid (ratio 1:1).

[0057] Primer coat material: Polyetheramine-based epoxy resin composite.

[0058] Intermediate coating material: A composite of nano-alumina and polyurethane-based material (ratio 1:4).

[0059] Top coating material: A composite of fluoropolymer and graphene (contact angle greater than 140 degrees).

[0060] 2. Process steps

[0061] Sandblasting treatment:

[0062] Carry out coarse-grained sandblasting treatment for 20 minutes to remove the scale.

[0063] Then carry out fine-grained sandblasting treatment for 15 minutes to improve the surface roughness.

[0064] Pickling activation:

[0065] Immerse the sandblasted wheels in the mixed acid for 45 minutes to ensure the removal of all microscopic contaminants.

[0066] Low-temperature plasma spraying:

[0067] Use low-temperature plasma spraying equipment to spray an epoxy resin composite material with hydroxyl functional groups on the aluminum alloy surface to ensure good chemical adhesion.

[0068] Intermediate coating spraying:

[0069] After the primer is cured, carry out multi-layer spraying using a composite material of nano-aluminum oxide and polyurethane. The thickness of each layer is controlled at 8 microns, the curing time is 2 hours, and the curing temperature is 60 °C.

[0070] Topcoat spraying:

[0071] Spray a composite material of fluoropolymer and graphene with superhydrophobic chemical modification on the intermediate coating, and carry out high-temperature curing treatment at a temperature of 120 °C for 3 hours.

[0072] Polishing treatment:

[0073] Carry out polishing treatment on the topcoat to improve its surface gloss and appearance quality.

[0074] Performance testing:

[0075] 1. Wear resistance test

[0076] Method: Use a wear testing machine and adopt standard abrasives (such as sandpaper) to test the wear amount of each sample.

[0077] Test conditions:

[0078] Load: 10 kg;

[0079] Time: 60 minutes;

[0080] Data recording:

[0081] Wear amount (unit: gram)

[0082] Sample Wear amount (g) Sample A 0.15 Sample B 0.12 Sample C 0.45

[0083] 2. Corrosion Resistance Test

[0084] Method: Place the sample in a salt spray test chamber, set the salt spray concentration to 5% NaCl solution, the temperature to 35 °C, and the duration to 48 hours.

[0085] Evaluation Criteria: Observe the surface changes of the coating, and record the number and size of corrosion points (unit: mm 2 ).

[0086] Sample Number of corrosion points <![CDATA[Corrosion area (mm 2 )]]> Sample A 2 5 Sample B 1 3 Sample C 10 25

[0087] 3. Adhesion Test

[0088] Method: Use the cross-cut method to conduct the adhesion test and evaluate the adhesion of the coating.

[0089] Evaluation Criteria: The peeled area after cross-cutting (unit: %).

[0090] Sample Adhesion peeling area (%) Sample A 2 Sample B 1 Sample C 15

[0091] Analysis of Experimental Results

[0092] Wear Resistance:

[0093] The wear amount of Sample A and Sample B is significantly lower than that of Sample C, indicating that the spraying process effectively improves the wear resistance.

[0094] Sample B has the lowest wear amount, showing the best wear resistance.

[0095] Corrosion Resistance:

[0096] The number and area of corrosion points of Sample A and Sample B are significantly lower than those of Sample C, indicating that the spraying process effectively improves the corrosion resistance.

[0097] Sample B has the best corrosion resistance and the smallest corrosion area.

[0098] Adhesion:

[0099] The peeled area of the adhesion of Sample A and Sample B is much lower than that of Sample C, indicating that the spraying process enhances the adhesion of the coating.

[0100] Sample B shows the best adhesion.

[0101] Conclusion

[0102] Based on the above experimental results, the following conclusions can be drawn:

[0103] The spraying processes of Example 1 and Example 2 have effectively improved the wear resistance, corrosion resistance, and adhesion of aluminum alloy wheels.

[0104] The effect of Example 2 is more significant, especially showing the best performance in terms of wear resistance and corrosion resistance, and is suitable for practical applications.

Claims

1. A wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels, characterized in that: The following steps are involved: a) Double sandblasting on the surface of aluminum alloy wheels, using coarse and fine grain aluminum oxide particles for secondary sandblasting to remove oxide scale and improve surface roughness; b) The blasted surface is pickled and activated by soaking with mixed acid to remove microscopic surface contaminants and generate a uniform active surface; c) after the activation treatment, using a low-temperature plasma-assisted spraying process, spraying an epoxy resin composite material containing hydroxyl functional groups on the surface of the aluminum alloy to form a chemical bond with the surface of the aluminum alloy; d) After the base coating is cured, a ceramic reinforced intermediate coating is sprayed. The intermediate coating is made of nano-alumina and polyurethane-based composite materials and is formed through multiple layered spraying processes. Each coating is controlled to be 5 to 10 microns; e) Finally, a fluorine-containing polymer and graphene composite material is sprayed on the intermediate coating as a top coating, and a high-temperature curing treatment is performed to form a dense protective film.

2. The wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels according to claim 1, characterized in that: The epoxy resin composite material in the primer layer includes polyetheramine epoxy resin.

3. The wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels according to claim 1 or 2, characterized in that: The ratio of nano-alumina to polyurethane-based composite material in the ceramic-reinforced intermediate coating is 1:2 to 1:

5.

4. The wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels according to claim 1, characterized in that: The surface coating of the fluorine-containing polymer and graphene composite material is treated by super-hydrophobic chemical modification, and its contact angle is greater than 140 degrees.

5. The wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels according to claim 1, characterized in that: During the spraying process, all coatings are carried out in a nitrogen protection environment to prevent impurities from being adsorbed on the coating surface.

6. The wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels according to claim 1, characterized in that: During the spraying process, each layer of the intermediate coating is subjected to a layered curing treatment at a temperature of 60 degrees Celsius for 2 hours.

7. The wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels according to claim 1, characterized in that: During the spraying process, the high temperature curing temperature of the top coating is 120 degrees Celsius and the time is 3 hours.

8. The wear-resistant and corrosion-resistant spraying process for aluminum alloy wheels according to claim 1, characterized in that: During the spraying process, the topcoat is polished to improve its surface gloss and appearance quality.

Images