CN117659814A - Preparation method of cerium oxide modified hexagonal boron nitride reinforced epoxy coating on surface of NdFeB magnet - Google Patents
Preparation method of cerium oxide modified hexagonal boron nitride reinforced epoxy coating on surface of NdFeB magnet Download PDFInfo
- Publication number
- CN117659814A CN117659814A CN202311650277.4A CN202311650277A CN117659814A CN 117659814 A CN117659814 A CN 117659814A CN 202311650277 A CN202311650277 A CN 202311650277A CN 117659814 A CN117659814 A CN 117659814A
- Authority
- CN
- China
- Prior art keywords
- ndfeb magnet
- electrophoresis
- solution
- hbn
- boron nitride
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910001172 neodymium magnet Inorganic materials 0.000 title claims abstract description 51
- 229920006334 epoxy coating Polymers 0.000 title claims abstract description 23
- 229910052582 BN Inorganic materials 0.000 title claims abstract description 14
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 title claims abstract description 14
- 229910000420 cerium oxide Inorganic materials 0.000 title claims abstract description 14
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 title claims abstract description 14
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 238000001962 electrophoresis Methods 0.000 claims abstract description 45
- 239000002131 composite material Substances 0.000 claims abstract description 29
- 239000011248 coating agent Substances 0.000 claims abstract description 23
- 238000000576 coating method Methods 0.000 claims abstract description 23
- 239000004593 Epoxy Substances 0.000 claims abstract description 20
- 239000000945 filler Substances 0.000 claims abstract description 18
- 239000007788 liquid Substances 0.000 claims abstract description 14
- 238000013329 compounding Methods 0.000 claims abstract description 4
- 239000000243 solution Substances 0.000 claims description 54
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 39
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 32
- 238000009210 therapy by ultrasound Methods 0.000 claims description 30
- 239000008367 deionised water Substances 0.000 claims description 26
- 229910021641 deionized water Inorganic materials 0.000 claims description 26
- 238000001035 drying Methods 0.000 claims description 20
- 238000010438 heat treatment Methods 0.000 claims description 20
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 18
- 238000003756 stirring Methods 0.000 claims description 18
- 238000005406 washing Methods 0.000 claims description 18
- 238000000034 method Methods 0.000 claims description 13
- HSJPMRKMPBAUAU-UHFFFAOYSA-N cerium(3+);trinitrate Chemical compound [Ce+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O HSJPMRKMPBAUAU-UHFFFAOYSA-N 0.000 claims description 12
- 239000011259 mixed solution Substances 0.000 claims description 10
- CTENFNNZBMHDDG-UHFFFAOYSA-N Dopamine hydrochloride Chemical compound Cl.NCCC1=CC=C(O)C(O)=C1 CTENFNNZBMHDDG-UHFFFAOYSA-N 0.000 claims description 8
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 8
- 239000007983 Tris buffer Substances 0.000 claims description 8
- 229960001149 dopamine hydrochloride Drugs 0.000 claims description 8
- 229910017604 nitric acid Inorganic materials 0.000 claims description 8
- 238000000967 suction filtration Methods 0.000 claims description 8
- LENZDBCJOHFCAS-UHFFFAOYSA-N tris Chemical compound OCC(N)(CO)CO LENZDBCJOHFCAS-UHFFFAOYSA-N 0.000 claims description 8
- 239000002033 PVDF binder Substances 0.000 claims description 6
- 239000002253 acid Substances 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 6
- 150000001875 compounds Chemical class 0.000 claims description 6
- 239000000839 emulsion Substances 0.000 claims description 6
- 235000019441 ethanol Nutrition 0.000 claims description 6
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims description 6
- 239000012530 fluid Substances 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 230000020477 pH reduction Effects 0.000 claims description 2
- 230000007797 corrosion Effects 0.000 abstract description 10
- 238000005260 corrosion Methods 0.000 abstract description 10
- 238000006460 hydrolysis reaction Methods 0.000 abstract 1
- 238000002203 pretreatment Methods 0.000 abstract 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 8
- 206010015150 Erythema Diseases 0.000 description 4
- 230000005587 bubbling Effects 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 4
- 231100000321 erythema Toxicity 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 238000007654 immersion Methods 0.000 description 4
- 239000010410 layer Substances 0.000 description 4
- 239000002932 luster Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 239000011780 sodium chloride Substances 0.000 description 4
- 230000003068 static effect Effects 0.000 description 4
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical compound [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 description 3
- 230000004888 barrier function Effects 0.000 description 3
- 239000003822 epoxy resin Substances 0.000 description 3
- 229920000647 polyepoxide Polymers 0.000 description 3
- 238000005275 alloying Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000009545 invasion Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000003917 TEM image Methods 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 229910021389 graphene Inorganic materials 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002715 modification method Methods 0.000 description 1
- 239000002135 nanosheet Substances 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
- C09D5/44—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes for electrophoretic applications
- C09D5/4419—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes for electrophoretic applications with polymers obtained otherwise than by polymerisation reactions only involving carbon-to-carbon unsaturated bonds
- C09D5/443—Polyepoxides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/24—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
- C09D5/08—Anti-corrosive paints
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
- C09D5/44—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes for electrophoretic applications
- C09D5/4419—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes for electrophoretic applications with polymers obtained otherwise than by polymerisation reactions only involving carbon-to-carbon unsaturated bonds
- C09D5/443—Polyepoxides
- C09D5/4457—Polyepoxides containing special additives, e.g. pigments, polymeric particles
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- Molecular Biology (AREA)
- Paints Or Removers (AREA)
Abstract
The invention discloses a preparation method of a cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of an NdFeB magnet, which particularly relates to the technical field of magnet coating, and comprises the steps of compounding a filler, pre-treatment of electrophoresis, preparation of electrophoresis liquid, electrophoresis of the NdFeB magnet in the electrophoresis liquid to form the epoxy coating, and curing of the coating, wherein PDA is successfully polymerized on hBN in an alkaline environment, and then Ce (NO 3 ) 3 Is subjected to hydrolysis reaction to giveSuccessful compounding to PDA-hBN. Then adding the composite filler into the electrophoresis liquid according to a certain concentration, and greatly improving the corrosion resistance of the epoxy composite coating formed by cathode electrophoresis.
Description
Technical Field
The invention relates to the field of magnet coating, in particular to a preparation method of a cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of an NdFeB magnet.
Background
The NdFeB serving as a third-generation rare earth permanent magnet material has excellent magnetic performance and characteristics of high magnetic energy product, high coercivity, high working performance and the like, and is mainly applied to the fields of motors, wind driven generators and the like. However, its unique multiphase structure and the large potential differences between the phases make it susceptible to corrosion failure, which is a major problem limiting its application development.
Current approaches to mitigate corrosion of neodymium-iron-boron magnets are mainly alloying and surface coating. The alloying technology mainly optimizes the magnetic structure by adding Dy, ce, cu, al, co, ti and other alloy elements, reduces the potential difference of each phase, and improves the corrosion resistance of the magnet. However, it also reduces the magnetic properties of the magnet and increases the production cost of the magnet. The surface coating technology is to build a coating layer with physical barrier property on the surface of the magnetic force, so as to prevent invasion of external corrosive medium, and generally, the structure and the property of the magnet are not changed. Among them, epoxy resin paint is receiving a lot of attention because of its low price, easy preparation, electrical insulation, strong adhesion, good chemical stability, etc., and currently, bisphenol a type epoxy resin, which is the epoxy paint, is most used in the market because of its better flexibility and lower viscosity. And as part of solvents volatilize in the curing process of the epoxy coating, micropore defects are easy to form, so that the external corrosive medium is rapidly invaded, and the industrial application of the epoxy coating is greatly limited. In the current research, the composite coating is prepared by adding various nano fillers such as g-C3N4, fe2O3, LDHs, siO2, hBN, ti3C2Tx, graphene and derivatives thereof, and the like, and the corrosion resistance of the epoxy coating can be improved by filling pores in the coating and delaying the invasion path of corrosive media, which is usually a passive physical barrier protection.
Disclosure of Invention
The invention aims to provide a preparation method of a cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of an NdFeB magnet, which aims to solve the problem of improving the corrosion resistance of the coating in the prior art.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the preparation method of the cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of the NdFeB magnet comprises the following steps:
1) Compounding of filler: dispersing hBN in Tris buffer solution, carrying out ultrasonic treatment for 1-2h, adding dopamine hydrochloride, stirring and carrying out ultrasonic treatment for 1-2h, heating and stirring the mixed solution in a water bath at 60 ℃, carrying out suction filtration on polyvinylidene fluoride filter paper, washing with absolute ethyl alcohol and deionized water for several times, drying at 60 ℃ for 24h to obtain a PDA-hBN compound, dispersing the PDA-hBN compound in ethanol solution, dripping cerium nitrate aqueous solution, stirring for 0.5h to fully mix, adjusting the pH value to 10 by NaOH solution, generating floccules in the solution, stirring for 1h, carrying out suction filtration again, washing and drying to obtain the PHBN-Ce compound;
2) Electrophoresis pretreatment: placing the NdFeB magnet in 0.3-6% nitric acid solution for acidizing for 15-50s, washing, placing in deionized water for ultrasonic treatment for 10-30s, placing in absolute ethanol solution for ultrasonic treatment for 1-5min, and drying for later use;
3) Preparing an electrophoresis liquid: preparing an original electrophoretic solution according to the proportion of color paste, epoxy emulsion and deionized water=1:4:5.4, stirring at room temperature for 24-48 hours for curing, then adding PDA-hBN composite filler, and carrying out ultrasonic treatment for 1-2 hours;
4) The NdFeB magnet is electrophoresed in an electrophoresis liquid to form an epoxy coating: placing the NdFeB magnet subjected to acid washing in an electrophoresis tank as a cathode for electrophoresis, and then washing off residual electrophoresis liquid on the surface by deionized water;
5) And (3) curing the coating: and (3) pre-drying the NdFeB magnet subjected to electrophoresis for 5-10min under a fan, and then placing the NdFeB magnet into a tube furnace for heating and curing for 70min.
Preferably, the Tris buffer concentration of step 1) is 1X 10 -5 The mol/L and the PH are prepared by dilute HCl solution for 8.5, and the water bath heating time is 5-10h.
Preferably, the mass ratio of hBN to dopamine hydrochloride in the mixed solution in the step 1) is 1:1, PDA-hBN and Ce (NO) 3 ) 3 The molar ratio of (2) is 1:1.
preferably, the mixed solution in the step 1) has a water bath temperature of 60 ℃ and a water bath time of 5 hours.
Preferably, in the pre-electrophoresis treatment process in the step 2), the NdFeB magnet is placed in a 0.3-6% concentration nitric acid solution for acidification treatment for 15-50s, washed and then placed in deionized water for ultrasonic treatment for 10-30s, and then placed in an absolute ethanol solution for ultrasonic treatment for 1-5min.
Preferably, the concentration of the composite PDA-hBN composite filler used for adding the electrophoresis liquid in the step 3) is 0.3-1.0g/L.
Preferably, in the step 4), the NdFeB magnet after pickling is used as a cathode for electrophoresis, the working voltage is 100V, the working environment temperature is 28-32 ℃, and the electrifying time is 60s.
Preferably, in the curing process described in step 5), the temperature is raised to 90 ℃ for 40min, and then raised to 180 ℃ for 30min.
Compared with the prior art, the invention has the beneficial effects that:
1. the non-covalent modification method of the modified hBN is simple, the reaction environment is easy to realize, the dispersibility of the hBN is greatly improved, and the whole reaction process is environment-friendly;
2. the Ce-containing oxide is used as a corrosion inhibitor, and the corrosion inhibition effect of the Ce-containing oxide can work cooperatively with the passive physical barrier effect of the hBN nano-sheet, so that the corrosion resistance of the epoxy composite coating is improved more obviously;
3. the modified PhBN-Ce is used as a filler to be added into the water-based epoxy resin, so that the self-dispersibility is improved, and parameters such as conductivity, pH and the like of the electrophoretic fluid are not influenced;
4. the method for preparing the epoxy composite coating is flexible and simple, has high raw material utilization rate, is easy to realize mechanical production, and has important significance for industrial production;
5. the prepared epoxy composite coating improves the corrosion resistance of the epoxy coating on the surface of the neodymium-iron-boron permanent magnet, and prolongs the service life of the neodymium-iron-boron permanent magnet under severe conditions;
drawings
FIG. 1 is a Zeta potential diagram of the original hBN, PDA-hBN and PhBN-Ce complex in water at the same concentration;
FIG. 2 is a TEM image of the PhBN-Ce complex obtained in example 2;
FIG. 3 is a cross-sectional SEM image of a PhBN-Ce reinforced epoxy composite coating obtained in example 2;
FIG. 4 is a polarization plot of NdFeB of the original epoxy coating (EP), ndFeB of the original hBN-enhanced epoxy composite coating at a concentration of 0.5g/L, ndFeB of the PhBN-Ce enhanced epoxy composite coating at a concentration of 0.3g/L, ndFeB of the PhBN-Ce enhanced epoxy composite coating at a concentration of 0.5g/L, and NdFeB sample of the PhBN-Ce enhanced epoxy composite coating at a concentration of 1.0 g/L;
Detailed Description
Example 1
S1: 150mg of hBN was first dispersed in Tris buffer (1X 10 -5 mol/L, pH=8.5), ultrasonic treatment is carried out for 1h, 150mg of dopamine hydrochloride is added, stirring is carried out for 1h, then the mixed solution is heated and stirred for 5h in a water bath at 60 ℃, then suction filtration is carried out on polyvinylidene fluoride filter paper, absolute ethyl alcohol and deionized water are used for cleaning for several times respectively, and drying is carried out for 24h at 60 ℃, thus obtaining the PDA-hBN composite filler. 50mg of PDA-hBN complex is then dispersed in 20ml of ethanol solution, 1ml of cerium nitrate aqueous solution (0.15M) is added dropwise, stirred for 0.5h to allow full mixing, then the pH is adjusted to 10 with NaOH solution, floc is generated in the solution, stirred for 1h, and then the solution is filtered again, washed and dried to obtain the PhBN-Ce complex.
S2: acidifying the NdFeB sample with 0.6% nitric acid solution for 50s, placing the sample in deionized water for ultrasonic treatment for 15s, placing the sample in absolute ethanol solution for ultrasonic treatment for 1min, and drying the sample for later use;
s3: preparing an original electrophoretic solution according to the proportion of color paste, epoxy emulsion and deionized water=1:4:5.4, stirring at room temperature for 48 hours for curing, adding PhBN-Ce composite filler with the concentration of 0.3g/L, and performing ultrasonic treatment for 1 hour;
s4: and (3) placing the NdFeB magnet subjected to acid washing in an electrophoresis tank as a cathode for electrophoresis, wherein electrophoresis parameters are as follows: 32 ℃,100V,60s. And then washing off the surface residual electrophoresis liquid by deionized water.
S5: pre-drying the NdFeB magnet subjected to electrophoresis for 10min under a fan, then placing the NdFeB magnet into a tube furnace, heating to 90 ℃ for 40min, heating to 180 ℃ for 30min, and heating at a speed of 5 ℃/min.
The obtained PhBN-Ce reinforced epoxy composite coating is dark black, uniform in color and luster, compact in film layer, and has the bubbling time of 480 hours and the erythema time of 720 hours in a static full immersion experiment (the concentration of NaCl solution is 3.5%).
Example 2
S1: 150mg of hBN was first dispersed in Tris buffer (1X 10 -5 mol/L, pH=8.5), ultrasonic treatment is carried out for 1h, 150mg of dopamine hydrochloride is added, stirring is carried out for 1h, then the mixed solution is heated and stirred for 5h in a water bath at 60 ℃, then suction filtration is carried out on polyvinylidene fluoride filter paper, absolute ethyl alcohol and deionized water are used for cleaning for several times respectively, and drying is carried out for 24h at 60 ℃, thus obtaining the PDA-hBN composite filler. 50mg of PDA-hBN complex is then dispersed in 20ml of ethanol solution, 1ml of cerium nitrate aqueous solution (0.15M) is added dropwise, stirred for 0.5h to allow full mixing, then the pH is adjusted to 10 with NaOH solution, floc is generated in the solution, stirred for 1h, and then the solution is filtered again, washed and dried to obtain the PhBN-Ce complex.
S2: acidifying the NdFeB sample with 0.6% nitric acid solution for 50s, placing the sample in deionized water for ultrasonic treatment for 15s, placing the sample in absolute ethanol solution for ultrasonic treatment for 1min, and drying the sample for later use;
s3: preparing an original electrophoretic solution according to the proportion of color paste, epoxy emulsion and deionized water=1:4:5.4, stirring at room temperature for 48 hours for curing, adding PhBN-Ce composite filler with the concentration of 0.5g/L, and performing ultrasonic treatment for 1 hour;
s4: and (3) placing the NdFeB magnet subjected to acid washing in an electrophoresis tank as a cathode for electrophoresis, wherein electrophoresis parameters are as follows: 32 ℃,100V,60s. And then washing off the surface residual electrophoresis liquid by deionized water.
S5: pre-drying the NdFeB magnet subjected to electrophoresis for 10min under a fan, then placing the NdFeB magnet into a tube furnace, heating to 90 ℃ for 40min, heating to 180 ℃ for 30min, and heating at a speed of 5 ℃/min.
The obtained PhBN-Ce reinforced epoxy composite coating is dark black, uniform in color and luster, compact in film layer, and has the bubbling time of 360 hours and the erythema time of 1800 hours in a static full immersion experiment (the concentration of NaCl solution is 3.5%).
Example 3
S1: 150mg of hBN was first dispersed in Tris buffer (1X 10 -5 mol/L, pH=8.5), ultrasonic treatment is carried out for 1h, 150mg of dopamine hydrochloride is added, stirring is carried out for 1h, then the mixed solution is heated and stirred for 5h in a water bath at 60 ℃, then suction filtration is carried out on polyvinylidene fluoride filter paper, absolute ethyl alcohol and deionized water are used for cleaning for several times respectively, and drying is carried out for 24h at 60 ℃, thus obtaining the PDA-hBN composite filler. 50mg of PDA-hBN complex is then dispersed in 20ml of ethanol solution, 1ml of cerium nitrate aqueous solution (0.15M) is added dropwise, stirred for 0.5h to allow full mixing, then the pH is adjusted to 10 with NaOH solution, floc is generated in the solution, stirred for 1h, and then the solution is filtered again, washed and dried to obtain the PhBN-Ce complex.
S2: acidifying the NdFeB sample with 0.6% nitric acid solution for 50s, placing the sample in deionized water for ultrasonic treatment for 15s, placing the sample in absolute ethanol solution for ultrasonic treatment for 1min, and drying the sample for later use;
s3: preparing an original electrophoretic solution according to the proportion of color paste, epoxy emulsion and deionized water=1:4:5.4, stirring at room temperature for 48 hours for curing, adding PhBN-Ce composite filler with the concentration of 1.0g/L, and performing ultrasonic treatment for 1 hour;
s4: and (3) placing the NdFeB magnet subjected to acid washing in an electrophoresis tank as a cathode for electrophoresis, wherein electrophoresis parameters are as follows: 32 ℃,100V,60s. And then washing off the surface residual electrophoresis liquid by deionized water.
S5: pre-drying the NdFeB magnet subjected to electrophoresis for 10min under a fan, then placing the NdFeB magnet into a tube furnace, heating to 90 ℃ for 40min, heating to 180 ℃ for 30min, and heating at a speed of 5 ℃/min.
The obtained PhBN-Ce reinforced epoxy composite coating is dark black, uniform in color and luster, compact in film layer, and has the bubbling time of 600 hours and the erythema time of 960 hours in a static full immersion experiment (the concentration of NaCl solution is 3.5%).
Example 4
S1: 150mg of hBN was first dispersed in Tris buffer (1X 10 -5 mol/L, pH=8.5), ultrasonic treatment is carried out for 1h, 150mg of dopamine hydrochloride is added, stirring is carried out for 1h, then the mixed solution is heated and stirred for 5h in a water bath at 60 ℃, then suction filtration is carried out on polyvinylidene fluoride filter paper, absolute ethyl alcohol and deionized water are used for cleaning for several times respectively, and drying is carried out for 24h at 60 ℃, thus obtaining the PDA-hBN composite filler. 50mg of PDA-hBN complex is then dispersed in 20ml of ethanol solution, 1ml of cerium nitrate aqueous solution (0.15M) is added dropwise, stirred for 0.5h to allow full mixing, then the pH is adjusted to 10 with NaOH solution, floc is generated in the solution, stirred for 1h, and then the solution is filtered again, washed and dried to obtain the PhBN-Ce complex.
S2: acidifying the NdFeB sample with 0.6% nitric acid solution for 15s, placing the sample in deionized water for ultrasonic treatment for 15s, placing the sample in absolute ethanol solution for ultrasonic treatment for 1min, and drying the sample for later use;
s3: preparing an original electrophoretic solution according to the proportion of color paste, epoxy emulsion and deionized water=1:4:5.4, stirring at room temperature for 48 hours for curing, then adding PDA-hBN composite filler with the concentration of 2.0g/L, and carrying out ultrasonic treatment for 1 hour;
s4: and (3) placing the NdFeB magnet subjected to acid washing in an electrophoresis tank as a cathode for electrophoresis, wherein electrophoresis parameters are as follows: 28 ℃,100V,60s. And then washing off the surface residual electrophoresis liquid by deionized water.
S5: pre-drying the NdFeB magnet subjected to electrophoresis for 10min under a fan, then placing the NdFeB magnet into a tube furnace, heating to 90 ℃ for 40min, heating to 180 ℃ for 30min, and heating at a speed of 5 ℃/min.
The obtained PhBN-Ce reinforced epoxy composite coating is dark black, uniform in color and luster, compact in film layer, and has the bubbling time of 240 hours and the erythema time of 480 hours in a static full immersion experiment (the concentration of NaCl solution is 3.5%).
Claims (8)
- The preparation method of the cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of the NdFeB magnet is characterized by comprising the following steps of:1) Compounding of filler: dispersing hBN in Tris buffer solution, carrying out ultrasonic treatment for 1-2h, adding dopamine hydrochloride, stirring and carrying out ultrasonic treatment for 1-2h, heating and stirring the mixed solution in a water bath at 60 ℃, carrying out suction filtration on polyvinylidene fluoride filter paper, washing with absolute ethyl alcohol and deionized water for several times, drying at 60 ℃ for 24h to obtain a PDA-hBN compound, dispersing the PDA-hBN compound in ethanol solution, dripping cerium nitrate aqueous solution, stirring for 0.5h to fully mix, adjusting the pH value to 10 by NaOH solution, generating floccules in the solution, stirring for 1h, carrying out suction filtration again, washing and drying to obtain the PHBN-Ce compound;2) Electrophoresis pretreatment: placing the NdFeB magnet in 0.3-6% nitric acid solution for acidizing for 15-50s, washing, placing in deionized water for ultrasonic treatment for 10-30s, placing in absolute ethanol solution for ultrasonic treatment for 1-5min, and drying for later use;3) Preparing an electrophoresis liquid: preparing an original electrophoretic solution according to the proportion of color paste, epoxy emulsion and deionized water=1:4:5.4, stirring at room temperature for 24-48 hours for curing, then adding PDA-hBN composite filler, and carrying out ultrasonic treatment for 1-2 hours;4) The NdFeB magnet is electrophoresed in an electrophoresis liquid to form an epoxy coating: placing the NdFeB magnet subjected to acid washing in an electrophoresis tank as a cathode for electrophoresis, and then washing off residual electrophoresis liquid on the surface by deionized water;5) And (3) curing the coating: and (3) pre-drying the NdFeB magnet subjected to electrophoresis for 5-10min under a fan, and then placing the NdFeB magnet into a tube furnace for heating and curing for 70min.
- 2. The method for preparing the NdFeB magnet surface cerium oxide modified hexagonal boron nitride reinforced epoxy coating according to claim 1, wherein the concentration of the Tris buffer solution in the step 1) is 1×10 -5 The mol/L and the PH are prepared by dilute HCl solution for 8.5, and the water bath heating time is 5-10h.
- 3. The method for preparing the NdFeB magnet surface cerium oxide modified hexagonal boron nitride reinforced epoxy coating according to claim 1, wherein the mass ratio of hBN to dopamine hydrochloride in the mixed solution in step 1) is 1:1, PDA-hBN and Ce (NO) 3 ) 3 The molar ratio of (2) is 1:1.
- 4. the method for preparing the cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of the NdFeB magnet according to claim 1, wherein the mixed solution in the step 1) has a water bath temperature of 60 ℃ for 5 hours.
- 5. The method for preparing the cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of the NdFeB magnet according to claim 1, wherein in the pre-electrophoresis treatment process in step 2), the NdFeB magnet is placed in a 0.3-6% concentration nitric acid solution for acidification treatment for 15-50s, washed, placed in deionized water for ultrasonic treatment for 10-30s, and then placed in an absolute ethanol solution for ultrasonic treatment for 1-5min.
- 6. The method for preparing the cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of the NdFeB magnet according to claim 1, wherein the concentration of the composite PDA-hBN composite filler added with the electrophoretic fluid in the step 3) is 0.3-1.0g/L.
- 7. The method for preparing the cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of the NdFeB magnet according to claim 1, wherein in the step 4), the acid-washed NdFeB magnet is used as a cathode for electrophoresis, the working voltage is 100V, the working environment temperature is 28-32 ℃, and the energizing time is 60s.
- 8. The method for preparing the cerium oxide modified hexagonal boron nitride reinforced epoxy coating on the surface of the NdFeB magnet according to claim 1, wherein the curing process in step 5) is performed by heating to 90 ℃ for 40min, and then heating to 180 ℃ for 30min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311650277.4A CN117659814A (en) | 2023-12-04 | 2023-12-04 | Preparation method of cerium oxide modified hexagonal boron nitride reinforced epoxy coating on surface of NdFeB magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311650277.4A CN117659814A (en) | 2023-12-04 | 2023-12-04 | Preparation method of cerium oxide modified hexagonal boron nitride reinforced epoxy coating on surface of NdFeB magnet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117659814A true CN117659814A (en) | 2024-03-08 |
Family
ID=90074586
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311650277.4A Pending CN117659814A (en) | 2023-12-04 | 2023-12-04 | Preparation method of cerium oxide modified hexagonal boron nitride reinforced epoxy coating on surface of NdFeB magnet |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117659814A (en) |
-
2023
- 2023-12-04 CN CN202311650277.4A patent/CN117659814A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103243371B (en) | Preparation method of zinc anode oxidation film layer | |
| CN107739534A (en) | A kind of alcohol radical inorganic composite coating and preparation method thereof | |
| Yu et al. | Synthesis and properties of PANI/SiO2 organic–inorganic hybrid films | |
| CN106544715A (en) | The method for improving Nd-Fe-B permanent magnet epoxy resin coating performance | |
| CN111777917A (en) | Preparation method of modified etched basalt scale/epoxy resin composite coating | |
| CN117659814A (en) | Preparation method of cerium oxide modified hexagonal boron nitride reinforced epoxy coating on surface of NdFeB magnet | |
| CN104387922B (en) | Water-based static conductive paint and preparation method thereof | |
| CN111253778A (en) | Preparation method of modified boron nitride nanosheet and application of modified boron nitride nanosheet | |
| CN113549387A (en) | Modified epoxy resin coating and preparation method thereof | |
| CN112176286A (en) | Coating, metal magnet with coating and preparation method of coating | |
| CN113564664A (en) | Preparation method of sintered NdFeB magnet surface modified carbon nanotube enhanced organic coating | |
| CN116285578A (en) | Preparation method of NdFeB surface modified hexagonal boron nitride reinforced epoxy composite coating | |
| CN114381786B (en) | Preparation method of high-wear-resistance high-corrosion-resistance protective coating on surface of neodymium iron boron | |
| CN106591922B (en) | Cu2Preparation method of O nano film | |
| CN101693806B (en) | Method for preparing cathode electrophoretic paint based on current carrier control technology | |
| CN117511342A (en) | Preparation method of NdFeB surface modified graphite-like phase carbon nitride reinforced epoxy coating | |
| CN114921782A (en) | Composite treating agent for surface pretreatment of neodymium iron boron magnet and preparation method and application thereof | |
| CN118772780A (en) | Preparation method of (Ce, nd) -Fe-B magnet surface epoxy modified organic silicon resin composite coating | |
| CN108467662B (en) | Preparation method of epoxy solution for neodymium iron boron magnet cathode electrophoresis | |
| CN100370559C (en) | Binding neodybium iron boron magnet surface cathode electrophoresis production technology | |
| CN114410204A (en) | Preparation method of polyurethane protective coating based on MXene nano intercalation compound | |
| CN104962945B (en) | A kind of electrochemical method for synthesizing of sea urchin shape micrometer/nanometer structure polyaniline | |
| CN102347180B (en) | CNT (carbon nano tube) cathode material and preparation method thereof | |
| CN113026071B (en) | Preparation method and application of conductive polymer and hexadecyl trimethyl ammonium bromide composite coating | |
| CN101781511A (en) | Antistatic coating taking rare-earth-modified barium zirconate titanate nano-powder as conductive filler, and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |