Coating material and method of manufacture

Abstract

The present application relates to the technical field of coating preparation, and in particular to a coating material and a preparation method; the present application adopts Cr, Co, Ni, Al and Mo powders mixed in a certain proportion, dried, ground, pressed, laser cladded, annealed and cooled to obtain a high-entropy alloy coating material; the cladding layer of the present application has high bonding strength with the substrate, the ferrocene and nickel metal complex can effectively enhance the bonding strength of the cladding layer with the substrate, the cladding layer is uniform and dense; the adhesive composed of polyvinyl alcohol can make the cladding layer uniform and dense, thereby improving the wear resistance and corrosion resistance of the coating; the cladding layer of the present application has good high-temperature oxidation resistance; the preparation process of the present application is simple and easy to implement, laser cladding is a fast, efficient and environmentally friendly preparation method, and the high-entropy alloy coating material can be produced on a large scale.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coating preparation, in particular to a coating material and a preparation method. BACKGROUND

[0002] Coating is a solid continuous film obtained by one-time application of paint, which is a plastic thin layer coated on metal, fabric, plastic and other substrates for protection, insulation, decoration and other purposes. Paint can be gaseous, liquid or solid, and the type and state of paint are usually determined according to the substrate to be sprayed. Improving the performance of coating is very important in the field of new materials.

[0003] The inventors believe that the coating materials prepared by the existing disclosed patent technologies generally have the technical problems of poor coating density, low bonding strength with the substrate, low hardness of the coating and high wear rate, and may have adverse defects such as bubbles, cavities or cracks in the coating. SUMMARY

[0004] One of the purposes of the present application is to provide a coating material, which has a uniform and dense cladding layer and good high-temperature oxidation resistance, wear resistance and corrosion resistance.

[0005] The second purpose of the present application is to provide a coating material and a preparation method, which uses Cr, Co, Ni, Al and Mo powders mixed in a certain proportion, dried, ground, pressed, laser cladded, annealed and cooled to obtain the coating material. The preparation process is simple, easy to operate, fast and efficient, and can produce high-entropy alloy coating materials on a large scale.

[0006] In order to achieve the above-mentioned purposes, the technical scheme of the present application is as follows:

[0007] A coating material and a preparation method, the operation steps of which are as follows:

[0008] S1: using an electric spark numerical control machine tool to process high-entropy alloy into a cylindrical bar of Φ50mmx10mm, and then using sandpaper to polish the surface of the bar;

[0009] S2: placing the polished bar into a cleaning solution and cleaning it with an ultrasonic cleaning instrument at the same time;

[0010] S3: mixing Cr, Co, Ni, Al and Mo powders in a certain proportion, and then placing the mixed powders into an oven for drying;

[0011] S4: grinding the dried powders to obtain a pre-coating powder;

[0012] S5: uniformly apply a metal-based polyvinyl alcohol binder with a mass concentration of 2-5% on the surface of the substrate, cover the substrate with a semicircular mold, and then uniformly apply the pre-coated powder on the surface of the substrate, and use a tablet press to compress the pre-coated powder;

[0013] S6: after compression, perform laser cladding under the protection of nitrogen, and then perform annealing at 900-1000℃, and after cooling, obtain a high-entropy alloy coating material.

[0014] Further limitation, the cleaning liquid is ethanol or acetone.

[0015] Further limitation, the ultrasonic cleaning time is 10-30min.

[0016] Further limitation, the mixing ratio of Cr, Co, Ni, Al, Mo powder is 0.05-0.25:0.2-0.75:0.1-1:0.3-1.25:0.5-1.5.

[0017] Further limitation, the drying temperature is 70-90℃, and the time is 20-40min.

[0018] Further limitation, the grinding time is 5-9h.

[0019] Further limitation, the compression pressure is 20-30MPa, and the time is 30-90s.

[0020] Further limitation, the laser cladding parameters are: power 1.5-3.0kW, spot diameter 2-6mm, scanning speed 5-10mm / s.

[0021] Further limitation, the preparation method of the metal-based polyvinyl alcohol binder is:

[0022] S1: according to mass fraction, take 0.03-0.6 parts of 5,5-divinyl-2,2-bipyridine, 0.2-0.5 parts of nickel nitrate, place in a sealed reaction kettle, replace air with nitrogen, then add 100-150 parts of dichloromethane, mix and stir at 30-40℃ for 10-20 hours;

[0023] S2: add 10-18 parts of mercapto polyvinyl alcohol, 0.3-2 parts of vinyl ferrocene, 1-5 parts of 4-allyl amino thiourea, 0.3-2 parts of triethylamine, mix and stir at 60-70℃ for 30-100 minutes, and distill off the dichloromethane;

[0024] S3: add 200-300 parts of polyvinyl alcohol and mix uniformly to obtain a metal-based polyvinyl alcohol binder.

[0025] The reaction mechanism of the metal-based polyvinyl alcohol adhesive is as follows:

[0026] (1) 5,5-divinyl-2,2-bipyridine is prepared with nickel nitrate to prepare a divinyl nickel metal complex as a crosslinking agent, which undergoes a mercapto-alkene addition reaction with mercapto polyvinyl alcohol;

[0027] (2) at the same time, vinyl ferrocene undergoes a mercapto-alkene addition reaction with mercapto polyvinyl alcohol;

[0028] (3) and then polyvinyl alcohol is compounded to obtain a metal-based polyvinyl alcohol adhesive.

[0029] The coating material and preparation method of the present application have the following remarkable effects compared with the prior art:

[0030] 1. The cladding layer of the present application has high bonding strength with the substrate, and the ferrocene and nickel metal complex can effectively enhance the bonding strength of the cladding layer with the substrate, and the cladding layer is uniform and dense: the adhesive composed of polyvinyl alcohol can make the cladding layer uniform and dense, thereby improving the wear resistance and corrosion resistance of the coating;

[0031] 2. The cladding layer of the present application has good high-temperature oxidation resistance, and the high-entropy alloy has excellent high-temperature oxidation resistance, so it can effectively resist oxidation corrosion in high-temperature environment;

[0032] 3. The preparation process of the present application is simple and easy to operate, and laser cladding is a fast, efficient and environmentally friendly preparation method, which can produce high-entropy alloy coating materials on a large scale. DETAILED DESCRIPTION

[0033] The present application will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present application and not to limit the scope of the present application.

[0034] 1. Hardness performance characterization: The hardness distribution of the cross-section of the coating is measured by a microhardness tester, the experimental load is 200gf, and the hardness load holding time is 15s. The dotting method is adopted from top to bottom along the cross-section direction, the distance between each hardness point is selected as 0.1mm, and the average value is taken until the substrate, 3 points are punched at each horizontal height.

[0035] 2. Friction and wear performance characterization: a multifunctional surface comprehensive performance tester is used to test the wear performance of the coating material: the friction pair selected for the friction and wear experiment is a YG6 ball with a diameter of 5mm, the experimental load is 30N, the wear time is 60min, and the running speed of the wear test is 0.1m / s; finally, the wear volume of each sample is accurately measured by the contour detector of the instrument. Example 1

[0036] A coating material and its preparation method, comprising the following steps:

[0037] S1: Using an electrical discharge machining (EDM) CNC machine tool, the high entropy alloy is processed into cylindrical bars with a diameter of 50mm and a diameter of 10mm, and then the surface of the bars is polished with sandpaper.

[0038] S2: After grinding, the bar is immersed in the cleaning solution and cleaned with an ultrasonic cleaner.

[0039] S3: Mix Cr, Co, Ni, Al and Mo powders in a certain proportion, and then dry them in an oven;

[0040] S4: Grind the dried powder to obtain pre-coated powder;

[0041] S5: Apply a 2% (w / w) metal-based polyvinyl alcohol binder evenly to the substrate surface, fit a semi-circular mold over the substrate, then apply the pre-coated powder evenly to the substrate surface, and press the pre-coated powder into place using a tablet press.

[0042] S6: The coated material after pressing is laser clad under nitrogen protection, then annealed at 900℃, and after cooling, a high-entropy alloy coating material is obtained.

[0043] The cleaning solution is ethanol.

[0044] The ultrasonic cleaning time is 10 minutes.

[0045] The mixing ratio of the Cr, Co, Ni, Al, and Mo powders is 0.05:0.2:0.1:0.3:0.5.

[0046] The drying temperature is 70℃ and the time is 20 minutes.

[0047] The grinding time is 5 hours.

[0048] The pressing pressure is 20 MPa and the time is 30 seconds.

[0049] The parameters for the laser cladding are: power of 1.5kW, spot diameter of 2mm, and scanning speed of 5mm / s.

[0050] The preparation method of the metal-based polyvinyl alcohol adhesive is as follows:

[0051] S1: Weigh 0.03g of 5,5-divinyl-2,2-bipyridine and 0.2g of nickel nitrate, place them in a sealed reaction vessel, purge with nitrogen to replace the air, then add 100g of dichloromethane, mix and stir at 30°C for 10 hours.

[0052] S2: Add 10g of mercaptopolyvinyl alcohol, 0.3g of vinyl ferrocene, 1g of 4-allylaminothiourea, and 0.3g of triethylamine. Mix and stir at 60°C for 30 minutes, and then distill to remove dichloromethane.

[0053] S3: Add 200g of polyvinyl alcohol and mix well to obtain a metal-based polyvinyl alcohol binder. Example 2

[0054] A coating material and its preparation method, comprising the following steps:

[0055] S1: Using an electrical discharge machining (EDM) CNC machine tool, the high entropy alloy is processed into cylindrical bars with a diameter of 50mm and a diameter of 10mm, and then the surface of the bars is polished with sandpaper.

[0056] S2: After grinding, the bar is immersed in the cleaning solution and cleaned with an ultrasonic cleaner.

[0057] S3: Mix Cr, Co, Ni, Al and Mo powders in a certain proportion, and then dry them in an oven;

[0058] S4: Grind the dried powder to obtain pre-coated powder;

[0059] S5: Apply a 3% (w / w) metal-based polyvinyl alcohol binder evenly to the substrate surface, fit a semi-circular mold over the substrate, then apply the pre-coated powder evenly to the substrate surface, and press the pre-coated powder into place using a tablet press.

[0060] S6: The coated material after lamination is laser clad under nitrogen protection, then annealed at 950°C, and after cooling, a high-entropy alloy coating material is obtained.

[0061] The cleaning solution is ethanol.

[0062] The ultrasonic cleaning time is 15 minutes.

[0063] The mixing ratio of the Cr, Co, Ni, Al, and Mo powders is 0.1:0.4:0.5:0.7:0.9.

[0064] The drying temperature is 75℃ and the time is 25 minutes.

[0065] The grinding time is 6 hours.

[0066] The pressing pressure is 25 MPa and the time is 50 seconds.

[0067] The parameters of the laser cladding are: power of 2kW, spot diameter of 3mm, and scanning speed of 6mm / s.

[0068] The preparation method of the metal-based polyvinyl alcohol adhesive is as follows:

[0069] S1: Weigh 0.2g of 5,5-divinyl-2,2-bipyridine and 0.3g of nickel nitrate, place them in a sealed reaction vessel, purge with nitrogen to replace the air, then add 110g of dichloromethane, mix and stir at 35°C for 14 hours.

[0070] S2: Add 13g of mercaptopolyvinyl alcohol, 1g of vinyl ferrocene, 2g of 4-allylaminothiourea, and 1g of triethylamine. Mix and stir at 65°C for 60 minutes, and then distill to remove dichloromethane.

[0071] S3: Add 240g of polyvinyl alcohol and mix well to obtain a metal-based polyvinyl alcohol binder. Example 3

[0072] A coating material and its preparation method, comprising the following steps:

[0073] S1: Using an electrical discharge machining (EDM) CNC machine tool, the high entropy alloy is processed into cylindrical bars with a diameter of 50mm and a diameter of 10mm, and then the surface of the bars is polished with sandpaper.

[0074] S2: After grinding, the bar is immersed in the cleaning solution and cleaned with an ultrasonic cleaner.

[0075] S3: Mix Cr, Co, Ni, Al and Mo powders in a certain proportion, and then dry them in an oven;

[0076] S4: Grind the dried powder to obtain pre-coated powder;

[0077] S5: Apply a 4% (w / w) metal-based polyvinyl alcohol binder evenly to the substrate surface, fit a semi-circular mold over the substrate, then apply the pre-coated powder evenly to the substrate surface, and press the pre-coated powder into place using a tablet press.

[0078] S6: The coated material after lamination is laser clad under nitrogen protection, then annealed at 950°C, and after cooling, a high-entropy alloy coating material is obtained.

[0079] The cleaning solution is acetone.

[0080] The ultrasonic cleaning time is 25 minutes.

[0081] The mixing ratio of the Cr, Co, Ni, Al, and Mo powders is 0.2:0.6:0.8:1:1.3.

[0082] The drying temperature is 85℃ and the time is 35 minutes.

[0083] The grinding time is 8 hours.

[0084] The pressing pressure is 25 MPa, and the time is 80 seconds.

[0085] The parameters for the laser cladding are: power of 2.5kW, spot diameter of 5mm, and scanning speed of 8mm / s.

[0086] The preparation method of the metal-based polyvinyl alcohol adhesive is as follows:

[0087] S1: Weigh 0.5g of 5,5-divinyl-2,2-bipyridine and 0.4g of nickel nitrate, place them in a sealed reaction vessel, purge with nitrogen to replace the air, then add 140g of dichloromethane, mix and stir at 35°C for 18 hours.

[0088] S2: Add 16g of mercaptopolyvinyl alcohol, 1.5g of vinyl ferrocene, 4g of 4-allylaminothiourea, and 1.5g of triethylamine. Mix and stir at 65°C for 90 minutes, and then distill to remove dichloromethane.

[0089] S3: Add 280g of polyvinyl alcohol and mix well to obtain a metal-based polyvinyl alcohol binder. Example 4

[0090] A coating material and its preparation method, comprising the following steps:

[0091] S1: Using an electrical discharge machining (EDM) CNC machine tool, the high entropy alloy is processed into cylindrical bars with a diameter of 50mm and a diameter of 10mm, and then the surface of the bars is polished with sandpaper.

[0092] S2: After grinding, the bar is immersed in the cleaning solution and cleaned with an ultrasonic cleaner.

[0093] S3: Mix Cr, Co, Ni, Al and Mo powders in a certain proportion, and then dry them in an oven;

[0094] S4: Grind the dried powder to obtain pre-coated powder;

[0095] S5: Apply a 5% (w / w) metal-based polyvinyl alcohol binder evenly to the substrate surface, fit a semi-circular mold over the substrate, then apply the pre-coated powder evenly to the substrate surface, and press the pre-coated powder into place using a tablet press.

[0096] S6: The coated material after pressing is laser clad under nitrogen protection, then annealed at 1000℃, and after cooling, a high-entropy alloy coating material is obtained.

[0097] The cleaning solution is acetone.

[0098] The ultrasonic cleaning time is 30 minutes.

[0099] The mixing ratio of the Cr, Co, Ni, Al, and Mo powders is 0.25:0.75:1:1.25:1.5.

[0100] The drying temperature is 90℃ and the time is 40 minutes.

[0101] The grinding time is 9 hours.

[0102] The pressing pressure is 30 MPa and the time is 90 seconds.

[0103] The parameters for the laser cladding are: power of 3.0kW, spot diameter of 6mm, and scanning speed of 10mm / s.

[0104] The preparation method of the metal-based polyvinyl alcohol adhesive is as follows:

[0105] S1: Weigh 0.6g of 5,5-divinyl-2,2-bipyridine and 0.5g of nickel nitrate, place them in a sealed reaction vessel, purge with nitrogen to replace the air, then add 150g of dichloromethane, mix and stir at 40°C for 20 hours.

[0106] S2: Add 18g of mercaptopolyvinyl alcohol, 2g of vinyl ferrocene, 5g of 4-allylaminothiourea, and 2g of triethylamine. Mix and stir at 70°C for 100 minutes, and then distill to remove dichloromethane.

[0107] S3: Add 300g of polyvinyl alcohol and mix well to obtain a metal-based polyvinyl alcohol binder.

[0108] Comparative Example 1

[0109] In this example, no metal-based polyvinyl alcohol adhesive is applied to the substrate surface when preparing the high-entropy alloy coating material; otherwise, it is the same as in Example 1.

[0110] Comparative Example 2

[0111] In this example, 5,5-divinyl-2,2-bipyridine is not added when preparing the metal-based polyvinyl alcohol binder; otherwise, it is the same as in Example 1.

[0112] Comparative Example 3

[0113] In this example, mercapto-polyvinyl alcohol is not added when preparing the metal-based polyvinyl alcohol binder; otherwise, it is the same as in Example 1.

[0114] Example test results:

[0115] Hardness / HV 0.2 ]] Wear rate / mm 3 * N -1 * m -1 ]]> Example 1 792 2.05 Example 2 819 1.96 Example 3 833 1.83 Example 4 825 1.89 Comparative Example 1 642 4.92 Comparative Example 2 706 3.67 Comparative Example 3 750 3.13

[0116] Based on the data analysis of the above embodiments and comparative examples, the high-entropy alloy coating material prepared by the present invention can effectively improve the hardness of high-entropy alloys and reduce the wear rate of high-entropy alloys.

[0117] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a coating material, comprising the following steps: S1: Using an electrical discharge machining (EDM) CNC machine tool, the high entropy alloy is processed into cylindrical bars with a diameter of 50mm and a diameter of 10mm, and then the surface of the bars is polished with sandpaper. S2: After grinding, the bar is immersed in the cleaning solution and cleaned with an ultrasonic cleaner. S3: Mix Cr, Co, Ni, Al, and Mo powders in a certain proportion, wherein the mixing ratio of Cr, Co, Ni, Al, and Mo powders is 0.05-0.25: 0.2-0.75: 0.1-1: 0.3-1.25: 0.5-1.5; after mixing, place the mixture in an oven to dry. S4: Grind the dried powder to obtain pre-coated powder; S5: Apply a 2-5% (w / w) metal-based polyvinyl alcohol binder evenly to the substrate surface, fit a semi-circular mold over the substrate, then evenly coat the pre-coated powder onto the substrate surface, and press the pre-coated layer using a tablet press; the preparation method of the metal-based polyvinyl alcohol binder is as follows: Weigh 0.03-0.6 parts of 5,5-divinyl-2,2-bipyridine and 0.2-0.5 parts of nickel nitrate by weight, place them in a sealed reactor, purge with nitrogen to replace the air, then add 100-150 parts of dichloromethane, mix and stir at 30-40°C for 10-20 hours. Add 10-18 parts of mercaptopolyvinyl alcohol, 0.3-2 parts of vinyl ferrocene, 1-5 parts of 4-allylaminothiourea, and 0.3-2 parts of triethylamine. Mix and stir at 60-70°C for 30-100 minutes, and remove dichloromethane by distillation. Add 200-300 parts of polyvinyl alcohol and mix well to obtain a metal-based polyvinyl alcohol binder; S6: The coated material after lamination is subjected to laser cladding under nitrogen protection. The parameters of the laser cladding are: power of 1.5-3.0kW, spot diameter of 2-6mm, and scanning speed of 5-10mm / s. Then, it is annealed at 900-1000℃ and cooled to obtain a high-entropy alloy coating material.

2. The method for preparing a coating material according to claim 1, characterized in that: The cleaning solution is ethanol or acetone.

3. The method for preparing a coating material according to claim 1, characterized in that: The ultrasonic cleaning time is 10-30 minutes.

4. The method for preparing a coating material according to claim 1, characterized in that: The drying temperature is 70-90℃ and the time is 20-40 minutes.

5. The method for preparing a coating material according to claim 1, characterized in that: The grinding time is 5-9 hours.

6. The method for preparing a coating material according to claim 1, characterized in that: The pressing pressure is 20-30 MPa, and the time is 30-90 seconds.

7. A coating material, characterized in that: The coating material obtained by the preparation method according to any one of claims 1 to 6.