Forming method of environment-friendly coating for enhancing wear resistance of aluminum three-dimensional plate

Abstract

The invention discloses a forming method of an environment-friendly coating for enhancing wear resistance of an aluminum three-dimensional plate, and belongs to the technical field of environment-friendly coatings, yttrium chloride heptahydrate and graphene oxide are subjected to surface acylating chlorination treatment through a hydrothermal combination calcination method, then nano silicon carbide is aminated, and a silicon carbide / graphene composite filler is obtained through an acylating chlorination-amidation method; then coating with hydrophobic titanium dioxide to obtain a composite filler, compounding the composite filler with water-borne epoxy resin, a dispersing agent and other substances in proportion, and uniformly stirring to obtain the composite environment-friendly coating. After the surface of an aluminum three-dimensional plate is pretreated, a composite environment-friendly coating is sprayed to the surface of the aluminum three-dimensional plate through a two-time spraying method, and the forming method of the environment-friendly coating for enhancing the wear resistance of the aluminum three-dimensional plate is completed. And a high-adhesion, high-wear-resistance and super-hydrophobic functional coating is formed on the surface of the aluminum three-dimensional plate.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of environment-friendly coating, and particularly relates to a forming method of environment-friendly coating for enhancing the wear resistance of aluminum three-dimensional plate. BACKGROUND

[0002] Environment-friendly coating, also known as green coating, refers to a kind of coating or coating material which significantly reduces the negative impact on the environment in the whole process of design, production, use and waste treatment, and is committed to protecting the health of users; the environment-friendly coating for enhancing the wear resistance of aluminum three-dimensional plate generally refers to a material with high wear resistance and environmental protection properties coated on the surface of an aluminum plate; the aluminum three-dimensional plate, as a kind of aluminum material treated by a special process, is widely used in the field of building decoration, and as the application field is continuously expanding, the performance requirements for the aluminum three-dimensional plate are also continuously increasing, especially in terms of wear resistance.

[0003] Chinese patent application with publication number CN104073116A discloses a preparation method of super-bipolar coating, a mixed solution is prepared by preparing a fluorine-containing silane polymer solution, adding tetraethyl orthosilicate, water and hydrochloric acid to perform hydrolysis reaction; nano-silicon dioxide is added to the mixed solution, and a composite sol is obtained by uniformly mixing, the composite sol is coated on a substrate, and the super-bipolar coating is obtained after solidification and drying; however, the nano-silicon dioxide is easy to agglomerate in the mixed solution, and if the dispersion is insufficient, a local loose structure is formed after the coating is solidified, resulting in poor adhesion between the coating and the substrate.

[0004] Chinese patent application with publication number CN106318184A discloses a preparation method of environment-friendly conductive super-hydrophobic coating, a hydrophobic modified water-based polyurethane emulsion is sprayed on the surface of a substrate and heated and solidified, an ethanol dispersion solution of modified carbon nanotubes is sprayed on the surface of the polyurethane, the ethanol solvent is completely volatilized, then a layer of hydrophobic water-based polyurethane is sprayed on the surface of the carbon nanotube coating and heated and solidified, and finally the composite coating with a sandwich structure is heat-treated in a vacuum oven to obtain the conductive super-hydrophobic coating; however, the chloride ion in salt spray has strong permeability in extreme environment, promotes corrosion, causes the polyurethane matrix to be unstable, and causes problems such as yellowing, powdering, brittleness, cracking and peeling of the coating, further affecting the service life of the coating. SUMMARY

[0005] The present application aims to provide a forming method of environment-friendly coating for enhancing the wear resistance of aluminum three-dimensional plate, which improves the wear resistance of the aluminum three-dimensional plate and solves the adhesion problem between the coating and the substrate, thereby prolonging the service life of the aluminum three-dimensional plate in open air or extreme environment.

[0006] The yttrium modified graphene nanosheet prepared in the application is grafted with amino carbonized silicon through chemical bonds to obtain a silicon carbide / graphene composite filler, and then the silicon carbide / graphene composite filler is coated with titanium dioxide and subjected to hydrophobic treatment, and then is compounded with water-based epoxy resin, dispersant and the like, and is sprayed on the surface of aluminum three-dimensional plate through a two-time spraying method to complete the forming method of an environmental protection coating for enhancing the wear resistance of aluminum three-dimensional plate.

[0007] The object of the application can be achieved by the following technical solutions:

[0008] The forming method of an environmental protection coating for enhancing the wear resistance of aluminum three-dimensional plate comprises the following steps:

[0009] Step one: using yttrium chloride heptahydrate as a yttrium source and graphene oxide, acyl chloride yttrium / graphene filler is obtained through hydrothermal combination calcination and surface acyl chloride; then nano silicon carbide is modified by silane coupling agent to obtain amino nano silicon carbide, and the amino nano silicon carbide is grafted on the surface of the acyl chloride yttrium / graphene filler through acyl chloride-acylamide reaction to obtain silicon carbide / graphene composite filler;

[0010] Step two: through sol-gel method and surface grafting fluorosilane, a hydrophobic nano titanium dioxide coating layer is constructed on the surface of the silicon carbide / graphene composite filler to obtain a composite filler coated with hydrophobic titanium dioxide; after the composite filler coated with hydrophobic titanium dioxide is compounded with water-based epoxy resin, dispersant, deionized water, zinc phosphate corrosion inhibitor, film forming aid, polyurethane thickening agent and mineral oil defoaming agent in proportion, it is stirred uniformly in stages to obtain a composite environmental protection coating;

[0011] Step three: the surface of the aluminum three-dimensional plate is polished with 400-500 mesh sandpaper in the same direction, and then the surface is scrubbed with non-woven fabric soaked with anhydrous ethanol, and is dried for 20-30 min for standby; the composite environmental protection coating is sprayed on the surface of the aluminum three-dimensional plate through a two-time spraying method, and is cooled to room temperature to complete the forming method of an environmental protection coating for enhancing the wear resistance of aluminum three-dimensional plate.

[0012] Further, the acyl chloride yttrium / graphene filler is prepared through the following steps:

[0013] The graphene oxide powder and deionized water are added into a reaction kettle, and are ultrasonically treated for 30-40 min; then the yttrium chloride heptahydrate is added, and is magnetically stirred for 3-4 h; after being placed for 24-26 h, it is transferred into a polytetrafluoroethylene-lined hydrothermal kettle, and is reacted at 150-160 DEG C for 12-14 h; after being cooled to room temperature, it is vacuum filtered, washed with deionized water until neutral, frozen at -70 DEG C for 2 h, and dried under vacuum for 48-50 h; then it is transferred into a vacuum tube furnace, and is kept at 750 DEG C under nitrogen for 1 h to obtain yttrium / graphene filler; the yttrium / graphene filler, methyltetrahydrofuran, thionyl chloride and N,N-dimethylformamide are added into a reaction kettle, and are stirred under nitrogen for 3-4 h; the solvent is removed by distillation under reduced pressure to obtain acyl chloride yttrium / graphene filler.

[0014] Further, the amount ratio of graphene oxide powder, deionized water, yttrium chloride heptahydrate, yttrium / graphene filler, methyltetrahydrofuran, thionyl chloride and N,N-dimethylformamide is 8-10 g:4-5 L:16-18 g:5-8 g:500-600 mL:50-60 mL:20-30 mL.

[0015] Further, the silicon carbide / graphene composite filler is prepared by the following steps:

[0016] The nanosilicon carbide, anhydrous ethanol and deionized water are added into a reaction kettle, stirred at 300-400 rpm and 50-60℃ for 30-40 min, then 3-aminopropyl triethoxysilane is added, and stirring is continued for 4-5 h, centrifuged at 3000-4000 rpm for 15-25 min, filtered, the filter cake is washed with deionized water for 3-5 times, and dried at 60-80℃ for 2-3 h to obtain aminated nanosilicon carbide; the aminated nanosilicon carbide, yttrium acyl chloride / graphene filler, anhydrous dimethyl sulfoxide, triethylamine are added into a reaction kettle, stirred at room temperature for 10-12 h, vacuum filtration, the filter cake is washed with deionized water for 3-5 times, and vacuum dried at 60-80℃ for 2-4 h to obtain a silicon carbide / graphene composite filler.

[0017] Further, the amount ratio of nanosilicon carbide, anhydrous ethanol, deionized water, 3-aminopropyl triethoxysilane, aminated nanosilicon carbide, yttrium acyl chloride / graphene filler, anhydrous dimethyl sulfoxide and triethylamine is 10-12 g:15-16 mL:40-50 mL:7-9 mL:5-6 g:5-6 g:1-1.2 L:10-12 mL.

[0018] Further, the hydrophobic titanium dioxide coated composite filler is prepared by the following steps:

[0019] The silicon carbide / graphene composite filler, anhydrous ethanol and deionized water are added into a reaction kettle, stirred for 20-30 min, then tetrabutyl titanate is added, and stirring is continued for 20-30 min, transferred to a 60-80℃ water bath and stirred for 8-10 h, the precipitate is collected and transferred to a 1 wt% tridecafluorooctyl triethoxysilane solution, soaked for 1-2 h, vacuum dried at 50-60℃ for 6-8 h, ground and refined, and passed through a 300 mesh sieve to obtain a hydrophobic titanium dioxide coated composite filler.

[0020] Further, the amount ratio of silicon carbide / graphene composite filler, anhydrous ethanol, deionized water, tetrabutyl titanate and tridecafluorooctyl triethoxysilane solution is 5-8 g:4-6 L:75-85 mL:135-145 mL:100-110 mL.

[0021] Further, the composite environment-friendly paint is prepared through the following steps:

[0022] The water-based epoxy resin, dispersant and deionized water are stirred at 600-800 rpm for 10-20 min, then the hydrophobic titanium dioxide coated composite filler is added, and stirred at 1200-1400 rpm for 30-40 min, then the zinc phosphate corrosion inhibitor, film forming aid, polyurethane thickening agent and mineral oil defoaming agent are added, and continue to stir at 300-400 rpm for 10-20 min, to obtain the composite environment-friendly paint.

[0023] Further, the water-based epoxy resin, dispersant, deionized water, hydrophobic titanium dioxide coated composite filler, zinc phosphate corrosion inhibitor, film forming aid, polyurethane thickening agent and mineral oil defoaming agent are used in a ratio of 60-80 mL: 1-1.2 g: 20-30 mL: 5-8 g: 2-2.2 g: 2-2.2 g: 0.5-0.7 g: 0.3-0.5 g.

[0024] Further, the two-spraying method is specifically prepared through the following steps:

[0025] The composite environment-friendly paint is sprayed on the treated aluminum substrate at a uniform speed along the same direction by a spray gun, and a wet film of 30-40 microns is formed on the surface, and is placed for 10-20 min, and is transferred to an oven for pre-curing at 70-80 DEG C for 2-3 h, and is sprayed again along the opposite direction, and a wet film of 50-60 microns is formed on the surface, and is placed for 15-25 min, and is pre-cured at 70-80 DEG C for 2-4 h, and is then cured at 100-120 DEG C for 3-4 h.

[0026] The beneficial effects of the present application are:

[0027] 1. The yttrium modified graphene-silicon carbide-hydrophobic titanium dioxide ternary composite filler is prepared, which is uniformly dispersed in the water-based epoxy resin environment-friendly matrix, and then combined with the substrate treatment and two-step spraying process, to finally form an environment-friendly coating with high adhesion, strong wear resistance and super-hydrophobicity on the surface of the aluminum three-dimensional plate, which significantly improves the service life of the aluminum three-dimensional plate.

[0028] 2. The yttrium / graphene filler in the present application combines the high strength and toughness of graphene with the high temperature stability and interface enhancement effect of yttrium, and the yttrium modified graphene forms a special layered structure, which helps to reduce the aggregation of graphene sheet layers, improve the dispersibility, and make the wear-resistant filler uniformly distributed; and can improve the composite effect with silicon carbide, further disperse the stress, and improve the interface adhesion between the coating and the aluminum substrate.

[0029] 3、The silicon carbide / graphene composite filler in the application, wherein the nano silicon carbide is one of the hardest materials in nature, is uniformly dispersed in the system by surface amination, avoids particle agglomeration, and when the coating is subjected to friction and scratching, the silicon carbide particles can bear part of the force, and after being grafted with the yttrium acyl chloride / graphene filler, a three-dimensional skeleton is formed, the epoxy resin penetrates and fills the pores and solidifies to form an interpenetrating composite structure, and the wear resistance of the material is improved.

[0030] 4、The hydrophobic titanium dioxide coating in the application is coated with titanium dioxide, the chemical inertness after the coating of titanium dioxide insulates the corrosion medium, the surface grafted fluorosilane forms a super-hydrophobic interface to block the penetration of water and oxygen, the photocatalytic activity of titanium dioxide is effectively inhibited to avoid degradation of the coating, and the functions of "physical isolation + chemical passivation" dual corrosion resistance and long-acting hydrophobic self-cleaning are realized. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0032] Embodiment 1: A forming method of an environment-friendly coating for enhancing the wear resistance of an aluminum three-dimensional plate, comprising the following steps:

[0033] S1: 8g of graphene oxide powder and 4L of deionized water are added to a reaction kettle, ultrasonic treatment is performed for 30min, then 16g of yttrium chloride heptahydrate is added, magnetic stirring is performed for 3h, and then the mixture is left to stand for 24h; the mixture is transferred to a polytetrafluoroethylene-lined hydrothermal kettle, reaction is performed at 150 DEG C for 12h, and then the mixture is cooled to room temperature; vacuum filtration is performed, and then the mixture is washed to neutral with deionized water; the mixture is frozen at-70 DEG C for 2h, and then vacuum drying is performed for 48h; the mixture is transferred to a vacuum tube furnace, and then heat preservation is performed at 750 DEG C under nitrogen for 1h to obtain yttrium-modified graphene; 5g of the yttrium-modified graphene, 500mL of methyltetrahydrofuran, 50mL of thionyl chloride and 20mL of N,N-dimethylformamide are added to a reaction kettle, stirring is performed under nitrogen for 3h, and then solvent removal is performed by distillation under reduced pressure to obtain yttrium acyl chloride / graphene filler.

[0034] The method combines hydrothermal treatment and calcination and surface acyl chloride treatment to reduce graphene agglomeration and improve dispersibility, and the yttrium improves the thermal conductivity and mechanical strength of the composite material, and the surface acyl chloride treatment improves the interface compatibility of the nano filler.

[0035] S2: 10 g of nanometer silicon carbide, 15 mL of anhydrous ethanol and 40 mL of deionized water were added to the reaction kettle, stirred at 300 rpm and 50°C for 30 min, then 7 mL of 3-aminopropyl triethoxysilane was added, and stirring was continued for 4 h, centrifuged at 3000 rpm for 15 min, filtered, and the filter cake was washed with deionized water for 3 times, dried at 60°C for 2 h to obtain aminated nanometer silicon carbide; 5 g of aminated nanometer silicon carbide, 5 g of yttrium chloride graphene filler, 1 L of anhydrous dimethyl sulfoxide, 10 mL of triethylamine were added to the reaction kettle, stirred at room temperature for 10 h, vacuum filtration, the filter cake was washed with deionized water for 3 times, vacuum dried at 60°C for 2 h to obtain a silicon carbide / graphene composite filler.

[0036] The covalent bonding of nanometer silicon carbide and yttrium / graphene composite filler by acyl chloride-amidation reaction constructs a ternary heterostructure, disperses stress, realizes the synergistic effect of silicon carbide and graphene, and improves the wear resistance, corrosion resistance and stability of the material.

[0037] S3: 5 g of silicon carbide / graphene composite filler, 4 L of anhydrous ethanol and 75 mL of deionized water were added to the reaction kettle, stirred for 20 min, then 135 mL of tetrabutyl titanate was added, stirred for another 20 min, transferred to a 60°C water bath and stirred for 8 h, the precipitate was collected and transferred to 100 mL of a 1% solution of tridecafluorooctyl triethoxysilane, soaked for 1 h, vacuum dried at 50°C for 6 h, ground and refined, and then passed through a 300 mesh sieve to obtain a hydrophobic titanium dioxide coated composite filler.

[0038] By sol-gel method and surface grafting of fluorosilane, a nanometer titanium dioxide coating layer is constructed on the surface of silicon carbide / graphene, and then the fluorosilane is modified to realize the super-hydrophobic function, and a "core-shell-molecular layer" three-level structure is constructed, with silicon carbide / graphene as the inner core, having wear resistance and toughening effect, nanometer titanium dioxide as the intermediate shell layer, having ultraviolet shielding and photocatalytic activity, and the outer surface being a fluorosilane molecular layer, providing a super-hydrophobic and stain-resistant barrier, and the three-dimensional integrated synergistic effect.

[0039] S4: 60 mL of aqueous epoxy resin, 1 g of dispersant and 20 mL of deionized water were stirred at 600 rpm for 10 min, then 5 g of hydrophobic titanium dioxide coated composite filler was added, stirred at 1200 rpm for 30 min, then 2 g of zinc phosphate corrosion inhibitor, 2 g of film forming aid, 0.5 g of polyurethane thickening agent and 0.3 g of mineral oil defoamer were added, and stirring was continued at 300 rpm for 10 min to obtain a composite environmentally friendly coating.

[0040] S5: The surface of the aluminum three-dimensional plate is polished with 400 mesh sandpaper in the same direction, and then the surface is scrubbed with non-woven fabric soaked in anhydrous ethanol, and then transferred to a drying oven at 50°C for 20 minutes for standby. The composite environmental protection paint is sprayed on the treated aluminum substrate by a spray gun at a uniform speed in the same direction, forming a 30μm wet film on the surface, standing for 10 minutes, and then transferred to an oven for pre-curing at 70°C for 2 hours. Spray again in the opposite direction, form a 50μm wet film on the surface, stand for 15 minutes, pre-cure at 70°C for 2 hours, then keep at 100°C for 3 hours, and cool to room temperature. A forming method of an environmental protection coating for enhancing the wear resistance of aluminum three-dimensional plate is completed.

[0041] Example 2: A forming method of an environmental protection coating for enhancing the wear resistance of aluminum three-dimensional plate, comprising the following steps:

[0042] S1: Put 9g of graphene oxide powder and 4.5L of deionized water into a reaction kettle, ultrasonic for 35min, then add 17g of yttrium chloride heptahydrate, magnetic stirring for 3.5h, standing for 25h, then transfer it to a polytetrafluoroethylene lined autoclave, react at 155°C for 13h, cool to room temperature, then vacuum filter, wash with deionized water until neutral, freeze at-70°C for 2h, and dry under vacuum for 49h. Then transfer it to a vacuum tube furnace, keep at 750°C under nitrogen for 1h, to obtain yttrium modified graphene; Put 6.5g of yttrium modified graphene, 550mL of methyltetrahydrofuran, 55mL of thionyl chloride and 25mL of N,N-dimethylformamide into a reaction kettle, stir under nitrogen for 3.5h, and remove the solvent by vacuum distillation to obtain yttrium chloride / graphene filler.

[0043] S2: Put 11g of nano silicon carbide, 15.5mL of anhydrous ethanol and 45mL of deionized water into a reaction kettle, stir at 350rpm and 55°C for 35min, then add 8mL of 3-aminopropyltriethoxysilane, continue to stir for 4.5h, centrifuge at 3500rpm for 20min, filter, wash the filter cake with deionized water 4 times, and dry at 70°C for 2.5h to obtain aminated nano silicon carbide; Put 5.5g of aminated nano silicon carbide, 5.5g of yttrium chloride / graphene filler, 1.1L of anhydrous dimethyl sulfoxide, and 11mL of triethylamine into a reaction kettle, stir at room temperature for 11h, vacuum filter, wash the filter cake with deionized water 4 times, and vacuum dry at 70°C for 3h to obtain a silicon carbide / graphene composite filler.

[0044] S3: 6.5 g of silicon carbide / graphene composite filler, 5 L of anhydrous ethanol and 80 mL of deionized water were added to the reaction kettle, stirred for 25 min, then 140 mL of tetrabutyl titanate was added, stirred for 25 min, transferred to a 70°C water bath and stirred for 9 h, the precipitate was collected and transferred to 105 mL of a 1% mass fraction of tridecafluoro-1-octyltriethoxysilane solution, soaked for 1.5 h, vacuum dried at 55°C for 7 h, ground and refined, and sieved through a 300 mesh sieve to obtain a hydrophobic titanium dioxide coated composite filler.

[0045] S4: 70 mL of aqueous epoxy resin, 1.1 g of dispersant and 25 mL of deionized water were stirred at 700 rpm for 15 min, then 6.5 g of hydrophobic titanium dioxide coated composite filler was added and stirred at 1300 rpm for 35 min, then 2.1 g of zinc phosphate corrosion inhibitor, 2.1 g of film forming aid, 0.6 g of polyurethane thickener and 0.4 g of mineral oil defoamer were added and stirred at 350 rpm for 15 min to obtain a composite environmentally friendly coating.

[0046] S5: The surface of the aluminum three-dimensional plate was polished in the same direction with 450 mesh sandpaper, and then the surface was scrubbed with non-woven fabric soaked with anhydrous ethanol, and then transferred to a 55°C oven for drying for 25 min for standby. The composite environmentally friendly coating was sprayed on the treated aluminum substrate at a uniform speed in the same direction by a spray gun, forming a 35 μm wet film on the surface, standing for 15 min, transferring to an oven for pre-curing at 75°C for 2.5 h, spraying again in the opposite direction, forming a 55 μm wet film on the surface, standing for 20 min, pre-curing at 75°C for 3 h, then curing at 110°C for 3.5 h, and cooling to room temperature to complete a forming method of an environmentally friendly coating for enhancing the wear resistance of an aluminum three-dimensional plate.

[0047] Example 3: A forming method of an environmentally friendly coating for enhancing the wear resistance of an aluminum three-dimensional plate, comprising the following steps:

[0048] S1: 10 g of graphene oxide powder and 5 L of deionized water were added to the reaction kettle, ultrasonicated for 40 min, then 18 g of yttrium chloride heptahydrate was added and magnetically stirred for 4 h, then left to stand for 26 h, then transferred to a polytetrafluoroethylene lined hydrothermal kettle, reacted at 160°C for 14 h, then cooled to room temperature, vacuum filtered, washed with deionized water until neutral, frozen at -70°C for 2 h, and vacuum dried for 50 h, then transferred to a vacuum tube furnace, heated at 750°C under nitrogen for 1 h to obtain yttrium modified graphene; 8 g of yttrium modified graphene, 600 mL of methyltetrahydrofuran, 60 mL of thionyl chloride and 30 mL of N,N-dimethylformamide were added to the reaction kettle, stirred under nitrogen for 4 h, and the solvent was removed by distillation under reduced pressure to obtain yttrium chloride / graphene filler.

[0049] S2: 12 g of nanometer silicon carbide, 16 mL of anhydrous ethanol and 50 mL of deionized water were added to the reaction kettle, stirred at 400 rpm and 60°C for 40 min, then 9 mL of 3-aminopropyl triethoxysilane was added, and stirring was continued for 5 h, centrifuged at 4000 rpm for 25 min, filtered, and the filter cake was washed with deionized water for 5 times, dried at 80°C for 3 h to obtain aminated nanometer silicon carbide; 6 g of aminated nanometer silicon carbide, 6 g of yttrium chloride graphene filler, 1.2 L of anhydrous dimethyl sulfoxide, and 12 mL of triethylamine were added to the reaction kettle, stirred at room temperature for 12 h, vacuum filtered, the filter cake was washed with deionized water for 5 times, and vacuum dried at 80°C for 4 h to obtain a silicon carbide / graphene composite filler.

[0050] S3: 8 g of silicon carbide / graphene composite filler, 6 L of anhydrous ethanol and 85 mL of deionized water were added to the reaction kettle, stirred for 30 min, then 145 mL of tetrabutyl titanate was added, stirred for another 30 min, transferred to a 80°C water bath and stirred for 10 h, the precipitate was collected and transferred to 110 mL of a 1% mass fraction of tridecafluorooctyl triethoxysilane solution, soaked for 2 h, vacuum dried at 60°C for 8 h, ground and refined, and sieved through a 300 mesh sieve to obtain a hydrophobic titanium dioxide coated composite filler.

[0051] S4: 80 mL of aqueous epoxy resin, 1.2 g of dispersant and 30 mL of deionized water were stirred at 800 rpm for 20 min, then 8 g of hydrophobic titanium dioxide coated composite filler was added, stirred at 1400 rpm for 40 min, then 2.2 g of zinc phosphate corrosion inhibitor, 2.2 g of film forming aid, 0.7 g of polyurethane thickener, and 0.5 g of mineral oil defoamer were added, and stirring was continued at 400 rpm for 20 min to obtain a composite environmentally friendly coating.

[0052] S5: The surface of the aluminum three-dimensional plate was polished in the same direction with 500 mesh sandpaper, and the surface was then scrubbed with non-woven fabric soaked with anhydrous ethanol, and then transferred to a 60°C oven for drying for 30 min for standby. The composite environmentally friendly coating was sprayed on the treated aluminum substrate at a uniform speed in the same direction by a spray gun, forming a 40 μm wet film on the surface, and then left to stand for 20 min, and then transferred to an oven for pre-curing at 80°C for 3 h, and then sprayed again in the opposite direction, forming a 60 μm wet film on the surface, and then left to stand for 25 min, and then pre-cured at 80°C for 4 h, and then heat treated at 120°C for 4 h, and then cooled to room temperature, to complete a method for forming an environmentally friendly coating for enhancing the wear resistance of an aluminum three-dimensional plate.

[0053] The process parameters for spraying by the spray gun were: spray gun caliber 1.2 mm, spraying pressure 0.8 MPa, and spray gun distance 20 cm.

[0054] The graphene oxide powder described in Examples 1-3 is selected from Zhongke Leiming (Beijing) Technology Co., Ltd. 7782-42-5; the thionyl chloride is selected from Shandong Xuchun Chemical Technology Co., Ltd. 7719-09-7; the nano silicon carbide is selected from Shanghai Pantian Powder Material Co., Ltd. PT-SiC-800nm; the water-based epoxy resin is selected from Shandong Haoyao New Material Co., Ltd. EP20; and the remaining raw materials are all commercially available products.

[0055] Comparative Example 1: The difference from Example 3 is that no yttrium chloride heptahydrate is added in step S1, the yttrium chloride acylate / graphene filler in step S2 is replaced by graphene acylate filler, and the remaining steps remain unchanged, to complete a forming method of an environmentally friendly coating for enhancing the wear resistance of aluminum three-dimensional plates.

[0056] Comparative Example 2: The difference from Example 3 is that no step S2 treatment is performed, the silicon carbide / graphene composite filler in step S3 is replaced by yttrium / graphene filler, and the remaining steps remain unchanged, to complete a forming method of an environmentally friendly coating for enhancing the wear resistance of aluminum three-dimensional plates.

[0057] Comparative Example 3: The difference from Example 3 is that no step S3 treatment is performed, the hydrophobic titanium dioxide coated composite filler in step S4 is replaced by silicon carbide / graphene composite filler, and the remaining steps remain unchanged, to complete a forming method of an environmentally friendly coating for enhancing the wear resistance of aluminum three-dimensional plates.

[0058] The aluminum three-dimensional plates prepared in Examples 1-3 and Comparative Examples 1-3 are cut into test samples of 70mm x 150mm x 2mm, and 11 parallel cuts are uniformly cut on the sample plate using a cross-cut board and a blade with a spacing of 1mm. Then, 3M tape is used to adhere and compact the sample, and the coating is observed for peeling at the scratch after being pulled repeatedly 5 times in a horizontal upward 45° direction. The adhesion of the test sample is tested. A X-575-T reciprocating linear wear tester produced by Shenzhen Xin Hengsen Trade Co., Ltd. is used to test the wear resistance of the test sample, and the experimental parameters are set as follows: load is 1kg / cm 2 , friction medium is flannel cloth, and wear rate is 40 cycles / min, 200 cycles. The hydrophobic performance of the test sample is tested according to the standard “GB / T30693-2014 Measurement of Contact Angle of Plastic Film with Water”. The corrosion resistance of the test sample is tested according to the standard “GB / T10125-2012 Salt Spray Test for Artificial Atmosphere Corrosion Test”.

[0059] The results are shown in Table 1:

[0060] Table 1: Performance test results of environmentally friendly coating for wear resistance of aluminum three-dimensional plates

[0061]

[0062] As can be seen from Table 1, the performance of the environmental-friendly coating forming method for enhancing the wear resistance of the aluminum three-dimensional plate completed in Examples 1-3 of the present application is significantly better than that of the comparative examples; by means of the modification of graphene interface by yttrium, the composite reinforcement of silicon carbide / graphene, the hydrophobic titanium dioxide coating, and the combination of environmental-friendly coating compounding and forming process, a functional coating with high adhesion, high wear resistance and super-hydrophobicity is formed on the surface of the aluminum three-dimensional plate.

[0063] The adhesion of the environmental-friendly coating in Comparative Example 1 is significantly decreased, which may be due to the fact that yttrium chloride heptahydrate is not added, so that the graphene is not modified by yttrium ions; the graphene modified by yttrium can form a special layered structure, which helps to reduce the aggregation of graphene sheet layers, improve the dispersibility, make the wear-resistant filler uniformly distributed and have better compatibility; the graphene modified by yttrium can also improve the composite effect with silicon carbide, further disperse the stress, and improve the interfacial adhesion of the coating and the aluminum substrate.

[0064] The wear resistance of the environmental-friendly coating in Comparative Example 2 is significantly decreased, which may be due to the fact that no nano-silicon carbide is grafted; the nano-silicon carbide is one of the hardest materials in nature, which is uniformly dispersed in the system by surface amination, so as to avoid particle aggregation; when the coating is subjected to friction and scratching, the silicon carbide particles can bear part of the force, and after being grafted with yttrium chloride / graphene filler, a three-dimensional skeleton is formed, the epoxy resin penetrates and fills the pores and solidifies, forming an interpenetrating composite structure, thereby improving the wear resistance of the material.

[0065] The hydrophobicity and salt fog resistance of the environmental-friendly coating in Comparative Example 3 are significantly decreased, which may be due to the fact that no hydrophobic titanium dioxide is protected; the titanium dioxide is uniformly coated on the surface of the silicon carbide / graphene particles, which has chemical inertness, and the shell layer has super-hydrophobicity by using tridecafluorooctyltriethoxysilane, thereby further blocking the corrosion of water, water vapor and corrosive medium, and improving the hydrophobicity and salt fog resistance of the overall filler and the coating.

[0066] Although the embodiments of the present application have been shown and described, it can be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the present application.

Claims

1. A method for forming an environmentally friendly coating that enhances the wear resistance of a three-dimensional aluminum plate, characterized in that, Includes the following steps: Step 1: Using yttrium chloride heptahydrate as the yttrium source and graphene oxide, yttrium chloride acylated / graphene filler is obtained through hydrothermal combined calcination and surface acylation. Then, nano-silicon carbide is modified with a silane coupling agent to obtain aminated nano-silicon carbide. Aminated nano-silicon carbide is grafted onto the surface of the yttrium chloride acylated / graphene filler through an acylation-amidation reaction to obtain silicon carbide / graphene composite filler. Step 2: A hydrophobic nano-titanium dioxide coating layer is constructed on the surface of the silicon carbide / graphene composite filler using the sol-gel method and surface grafting of fluorosilane, resulting in a hydrophobic titanium dioxide-coated composite filler. This filler is then mixed with waterborne epoxy resin, dispersant, deionized water, zinc phosphate corrosion inhibitor, film-forming aid, polyurethane thickener, and mineral oil defoamer in a specific ratio and stirred evenly in stages to obtain a composite environmentally friendly coating. Step 3: Sand the surface of the aluminum 3D panel with 400-500 grit sandpaper in the same direction, then wipe the surface with a non-woven cloth soaked in anhydrous ethanol, and dry for 20-30 minutes; apply the composite environmentally friendly coating to the surface of the aluminum 3D panel in two spraying processes, and cool to room temperature to complete the forming method of an environmentally friendly coating that enhances the wear resistance of the aluminum 3D panel.

2. The molding method of the environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 1, characterized in that, The yttrium chloride / graphene filler described in step one is prepared through the following steps: Graphene oxide powder and deionized water were added to a reaction vessel and sonicated for 30-40 min. Then, yttrium chloride heptahydrate was added, and the mixture was magnetically stirred for 3-4 h. After standing for 24-26 h, it was transferred to a hydrothermal reactor lined with polytetrafluoroethylene and reacted at 150-160 °C for 12-14 h. After cooling to room temperature, it was vacuum filtered, washed with deionized water until neutral, frozen at -70 °C for 2 h, and dried under vacuum for 48-50 h. It was then transferred to a vacuum tube furnace and held at 750 °C for 1 h under nitrogen to obtain yttrium / graphene filler. Yttrium / graphene filler, methyltetrahydrofuran, thionyl chloride, and N,N-dimethylformamide were added to a reaction vessel and stirred under nitrogen for 3-4 h. The solvent was removed by vacuum distillation to obtain yttrium chloride / graphene filler.

3. The molding method for an environmentally friendly coating that enhances the wear resistance of a three-dimensional aluminum plate according to claim 2, characterized in that, The ratio of the following components to be used is 8-10g:4-5L:16-18g:5-8g:500-600mL:50-60mL:20-30mL.

4. The molding method of the environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 1, characterized in that, The silicon carbide / graphene composite filler mentioned in step one is prepared through the following steps: Nano-silicon carbide, anhydrous ethanol, and deionized water are added to a reaction vessel and stirred at 300-400 rpm and 50-60℃ for 30-40 min. Then, 3-aminopropyltriethoxysilane is added, and stirring continues for 4-5 h. The mixture is then centrifuged at 3000-4000 rpm for 15-25 min, filtered, and the filter cake is washed 3-5 times with deionized water and dried at 60-80℃ for 2-3 h to obtain aminated nano-silicon carbide. Aminated nano-silicon carbide, yttrium chloride / graphene filler, anhydrous dimethyl sulfoxide, and triethylamine are added to a reaction vessel and stirred at room temperature for 10-12 h. The mixture is then vacuum filtered, and the filter cake is washed 3-5 times with deionized water and dried at 60-80℃ for 2-4 h to obtain silicon carbide / graphene composite filler.

5. The molding method of an environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 4, characterized in that, The ratio of the following components is as follows: nano-silicon carbide, anhydrous ethanol, deionized water, 3-aminopropyltriethoxysilane, aminated nano-silicon carbide, yttrium chloride / graphene filler, anhydrous dimethyl sulfoxide, and triethylamine is 10-12g: 15-16mL: 40-50mL: 7-9mL: 5-6g: 5-6g: 1-1.2L: 10-12mL.

6. The molding method of an environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 1, characterized in that, The hydrophobic titanium dioxide-coated composite filler described in step two is specifically achieved through the following steps: Silicon carbide / graphene composite filler, anhydrous ethanol, and deionized water were added to a reaction vessel and stirred for 20-30 minutes. Then tetrabutyl titanate was added and stirred for another 20-30 minutes. The mixture was then transferred to a water bath at 60-80°C and stirred for 8-10 hours. The precipitate was collected and transferred to a 1 wt% tridecafluorooctyltriethoxysilane solution and soaked for 1-2 hours. The mixture was then vacuum dried at 50-60°C for 6-8 hours, ground into a fine powder, and passed through a 300-mesh sieve to obtain a hydrophobic titanium dioxide-coated composite filler.

7. The molding method of an environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 6, characterized in that, The ratio of the silicon carbide / graphene composite filler, anhydrous ethanol, deionized water, tetrabutyl titanate, and tridecafluorooctyltriethoxysilane solution is 5-8g: 4-6L: 75-85mL: 135-145mL: 100-110mL.

8. The molding method of the environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 1, characterized in that, The composite environmentally friendly coating is prepared through the following steps: Waterborne epoxy resin, dispersant, and deionized water are stirred at 600-800 rpm for 10-20 minutes. Then, hydrophobic titanium dioxide-coated composite filler is added, and the mixture is stirred at 1200-1400 rpm for 30-40 minutes. Next, zinc phosphate corrosion inhibitor, film-forming aid, polyurethane thickener, and mineral oil defoamer are added, and the mixture is stirred at 300-400 rpm for another 10-20 minutes to obtain a composite environmentally friendly coating.

9. The molding method of an environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 8, characterized in that, The ratio of waterborne epoxy resin, dispersant, deionized water, hydrophobic titanium dioxide-coated composite filler, zinc phosphate corrosion inhibitor, film-forming aid, polyurethane thickener, and mineral oil defoamer is 60-80mL: 1-1.2g: 20-30mL: 5-8g: 2-2.2g: 2-2.2g: 0.5-0.7g: 0.3-0.5g.

10. The molding method of an environmentally friendly coating for enhancing the wear resistance of a three-dimensional aluminum plate according to claim 1, characterized in that, The two-coating method in step three is specifically implemented through the following steps: The composite environmentally friendly coating is sprayed onto the treated aluminum substrate at a uniform speed and in the same direction using a spray gun, forming a 30-40μm wet film on the surface. After standing for 10-20 minutes, it is transferred to an oven and pre-cured at 70-80℃ for 2-3 hours. The coating is then sprayed again in the opposite direction, forming a 50-60μm wet film on the surface. After standing for 15-25 minutes, it is pre-cured at 70-80℃ for 2-4 hours, and then kept at 100-120℃ for 3-4 hours.

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