Iron-based amorphous alloy coating sealing agent and sealing process thereof

Abstract

The application discloses a novel iron-based amorphous alloy coating sealing agent and a sealing process thereof, relates to the technical field of surface engineering, and is a combination of an inorganic rare earth sealing agent and an organic sealing agent, and the preparation method steps are as follows: S1, coating surface treatment; S2, preparation of an inorganic sealing agent; S3, preparation of an organic sealing agent; S4, coating sealing treatment; the method has the following advantages: (1) the novel sealing agent is non-toxic, safe and green; (2) the sealing process is simple, and complex steps such as heating sealing, vacuum sealing or ultrasonic sealing required by traditional sealing agents are avoided; (3) the corrosion performance of the coating after sealing is greatly improved, meanwhile, the coating surface is endowed with super-hydrophobicity and self-cleaning property, and the antifouling performance of the coating surface is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of surface engineering, in particular to a sealing method for iron-based amorphous coating. BACKGROUND

[0002] The iron-based amorphous alloy coating produced by the supersonic flame spraying technology has excellent corrosion resistance due to its low crystal defects and long-term disorder, which greatly improves its application in the industry of nuclear waste storage facilities and offshore corrosion-resistant parts. However, due to different spraying angles, particle rebound and shielding effect caused by coating shrinkage during the solidification process in the spraying process, serious porosity defects will inevitably occur in the coating. As a liquid channel, porosity will promote the penetration of electrolyte to the coating / substrate interface. This will cause the coating to delaminate and eventually peel off. Porosity-induced corrosion is one of the most common failure modes of engineering structures. Sealing treatment technology is widely used in sealing of porous coatings due to its simple operation and low manufacturing cost. By penetrating, plugging and filling the pores on the surface and inside of the coating with a sealing agent, the density of the coating is improved, thereby inhibiting the migration of corrosion factors.

[0003] The sealing process currently adopted for amorphous coatings is mostly through heating treatment of the sealing agent or combined with special treatment such as electrochemical polarization treatment, vacuum infiltration and ultrasonic assistance, but high temperature will cause the amorphous coating to crystallize, which will change the excellent performance of the coating. Special treatment is acceptable for small components, but for special large components and actual structural engineering components, in addition to complex operation, the cost will also be greatly increased. Therefore, the sealing method for iron-based amorphous coating can effectively solve the above problems, and has low cost, simple operation, and greatly improved corrosion performance. SUMMARY

[0004] In view of the corrosion problem of porosity-induced iron-based amorphous coating equipment key components, the sealing treatment is further carried out on the iron-based amorphous coating, and the sealing method for iron-based amorphous coating is provided, which not only realizes efficient sealing of the coating, but also realizes excellent superhydrophobicity and self-cleaning property, and has outstanding corrosion resistance, and has the advantages of simple surface treatment process, high efficiency and low cost.

[0005] To achieve the above purpose, the technical scheme adopted by the present application is as follows: a sealing method for iron-based amorphous coating, comprising the following steps:

[0006] (1) coating surface treatment: cleaning the surface of the coating to be treated;

[0007] (2) Preparation of inorganic sealing agent: 5-10 g (preferably 5-8 g) of neodymium nitrate, 10-15 ml (preferably 10-12 ml) of hydrogen peroxide (10-30% by mass) are dispersed into 500 ml of deionized water, and stirring is performed to obtain an inorganic sealing agent;

[0008] (3) Preparation of organic sealing agent: butyl acetate is added to the epoxy resin to dilute and obtain a mixed solution, the addition amount of butyl acetate is 75%-95% of the mass of the mixed solution; then 1H, 1H, 2H, 2H-perfluorodecyltriethylsilane (FDTES) is added to the mixed solution for surface modification, the addition amount of FDTES is 1%-3% of the mass of the organic sealing agent, and finally the organic sealing agent is obtained;

[0009] (4) Sealing treatment of the coating: the sealing method is dipping, the coating is first dipped into the inorganic rare earth sealing agent, dried, then dipped into the organic sealing agent, and dried and solidified to obtain the coating after sealing treatment.

[0010] Preferably, the iron-based amorphous coating is prepared by using a high-velocity air fuel (HVAF) spraying technique to spray the iron-based amorphous coating on the surface of the pretreated substrate in multiple passes to obtain an iron-based amorphous coating with micron-level roughness; the composition of the iron-based amorphous alloy is as follows: Fe 余量 Cr 18-21 Mo 5-9 Ni 2-5 P 9-15 B 1-5 C 2-6 Si 1-5 (at. % atomic percentage).

[0011] The HVAF supersonic flame spraying process is to heat and melt the iron-based amorphous alloy powder with a particle size range of 18-53 μm and spray it onto the surface of the substrate or member;

[0012] The HVAF supersonic flame spraying process parameters are as follows: air pressure 70-90 psi (preferably 75-85 psi); propane gas pressure 70-95 psi (preferably 75-90 psi); propane flow rate: 90-160 SLPM (110-150 SLPM); hydrogen flow rate: 10-40 SLPM (20-30 SLPM); nitrogen flow rate: 10-30 SLPM (15-25 SLPM); powder feeding rate: 40-70 g / min (preferably 45-65 g / min); spraying distance: 200-350 mm (preferably 220-300 mm);

[0013] The obtained coating thickness is between 400-500 μm.

[0014] Preferably, the cleaning process in step (1) is: sequentially using acetone solution and deionized water to clean the coating, and finally using ethanol to clean the coating, and then naturally drying for more than 5 min, preferably 10-30 min.

[0015] Preferably, the stirring time in step (2) is more than 5 min, preferably 20-40 min.

[0016] Preferably, the epoxy resin in step (3) is bisphenol A type epoxy resin.

[0017] Preferably, the hole sealing method in step (4) is immersion method:

[0018] First, the surface treated coating is immersed in the inorganic rare earth hole sealing agent for 10-50 min (preferably 15-45 min, more preferably 20-40 min), so that the inorganic hole sealing agent penetrates into the coating pores and forms a neodymium-based rare earth conversion film on the surface of the coating. The coating is taken out and dried in air at room temperature for 1-6 h (preferably 2-5 h, more preferably 2-4 h).

[0019] Secondly, after inorganic sealing, the coating is immersed in the organic hole sealing agent for organic sealing and surface modification, and the immersion time is 20-100 min (preferably 40-80 min, more preferably 50-70 min). Finally, drying and curing treatment is carried out; the drying and curing treatment process is room temperature drying for 8-24 h (preferably 10-16 h, more preferably 12-14 h), and finally a sealed coating is obtained.

[0020] The principle of the method of the application is that by using inorganic-organic composite hole sealing agent hybrid sealing treatment on the iron-based amorphous alloy coating, the sealing property of the iron-based amorphous coating is improved, and the coating also has higher corrosion resistance and self-cleaning property. The main principle is that the inorganic rare earth hole sealing agent is used to seal the iron-based amorphous coating for the first time, and a neodymium-based rare earth oxide film is formed on the surface of the coating. This rare earth oxide conversion film not only has good shielding effect, but also has a large number of hydroxyl groups on the surface, which provides convenience for the grafting and surface modification of the organic hole sealing agent. The organic hole sealing agent realizes the second sealing of the coating, not only fills the cracks on the surface of the coating after the inorganic rare earth hole sealing agent, but also further enhances the bonding strength between the hole sealing agent and the coating, and endows the coating with new functions, realizing super-hydrophobicity. Therefore, the inorganic-organic composite synergistic sealing effect can significantly improve the corrosion resistance of the coating.

[0021] The beneficial effects of the application are:

[0022] (1) The novel hole sealing agent of the application is non-toxic, safe and green;

[0023] (2) The sealing process is simple, and avoids the complex steps such as heating sealing, vacuum sealing or ultrasonic sealing of the traditional sealing agent;

[0024] (3) The corrosion performance of the coating after sealing is greatly improved, and the coating surface is endowed with super-hydrophobicity and self-cleaning property, thereby improving the anti-fouling performance of the coating surface. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The iron-based amorphous coating prepared in the application: (a) is a DSC graph of the coating, (b) is an XRD graph of the coating, and (c) is a TEM graph of the coating;

[0026] Figure 2 The preparation flow chart of the sealing agent in the application;

[0027] Figure 3 (a) and (c) are the surface and cross-section SEM graphs of the original coating in the application; (b) and (d) are the surface and cross-section SEM graphs of the sealed coating in the application;

[0028] Figure 4 The water jet experiment of the sealed coating in the application;

[0029] Figure 5 The electrochemical results of the sealed coating in the application;

[0030] Figure 6 The wetting behavior of Comparative Examples 1 and 2;

[0031] Figure 7 The electrochemical results of Comparative Examples 1 and 2. DETAILED DESCRIPTION

[0032] The application will be further described in detail below with reference to the accompanying drawings and examples. The following examples are intended to facilitate the understanding of the application, and do not limit the application in any way. Modifications and replacements of the method, steps or conditions of the application, without departing from the spirit and essence of the application, all belong to the scope of the application. If not specifically indicated, the technical means used in the examples is the conventional means familiar to those skilled in the art.

[0033] Example 1

[0034] A sealing method of an iron-based amorphous coating, comprising the following steps:

[0035] The iron-based amorphous coating is prepared by using a high-velocity air fuel (HVAF) spraying technology to spray multiple times on the surface of a pretreated substrate to obtain an iron-based amorphous coating with a micron-level roughness; the composition of the iron-based amorphous alloy is: Fe 50 Cr 18 Mo 7.5 Ni 3. 5P12 B3C 3.5 Si 2.5 (at.%atomic ratio).

[0036] The HVAF high velocity air fuel spraying process is to heat and melt the iron-based amorphous alloy powder with a particle size range of 35 μm and spray it to the surface of the substrate or component;

[0037] The HVAF high velocity air fuel spraying process parameters are: air pressure 80 psi; propane gas pressure 80 psi; propane flow rate: 130 SLPM; hydrogen flow rate: 25 SLPM; nitrogen flow rate: 23 SLPM; powder feeding rate: 60 g / min; spraying distance: 260 mm;

[0038] The obtained coating thickness is 450 μm.

[0039] (1) Coating surface treatment: the surface of the coating to be treated is cleaned; the cleaning process is: the coating is cleaned with acetone solution and deionized water in turn, and finally cleaned with ethanol, and then naturally dried for 15 min.

[0040] (2) Preparation of inorganic sealing agent: 5 g of neodymium nitrate and 10 ml of hydrogen peroxide (20% mass concentration) are dispersed into 500 ml of deionized water and stirred for 30 min to obtain an inorganic sealing agent;

[0041] (3) Preparation of organic sealing agent: butyl acetate is added to bisphenol A type epoxy resin to obtain a mixed solution, and the addition amount of butyl acetate is 85% of the mass of the mixed solution; then 1H, 1H, 2H, 2H-perfluorodecyltriethylsilane (FDTES) is added to the mixed solution for surface modification, and the addition amount of FDTES is 1% of the mass of the organic sealing agent, and finally the organic sealing agent is obtained;

[0042] (4) Sealing treatment of the coating: the sealing method is immersion method, first immerse the coating after surface treatment into the inorganic rare earth sealing agent, the immersion time is 35 min, so that the inorganic sealing agent penetrates into the coating pores, and a neodymium-based rare earth conversion film is formed on the surface of the coating, and then the coating is taken out and dried in air at room temperature for 2 h.

[0043] Secondly, after inorganic sealing, the coating is immersed in the organic sealing agent for organic sealing and surface modification at the same time, the immersion time is 50 min, and finally the drying and curing treatment is carried out; the drying and curing treatment process is room temperature drying for 12 h, and finally the sealed coating is obtained.

[0044] Result analysis: Figure 1(a) and (b) are DSC and XRD patterns of the iron-based amorphous coating in Example 1, in order to quantify the content of amorphous in the iron-based amorphous layer, the DSC heat flow diagram of the strip and the coating sample is given, the fraction of amorphous phase contained in the coating can be evaluated by the crystallization enthalpy (ΔH), that is, in the DSC curve, the ratio of the crystallization enthalpy ΔH of the coating and the strip sample, the amorphous content of the coating is calculated to be 98.9%, which is almost close to completely amorphous. In the XRD patterns of the iron-based amorphous coating and the strip, there is a relatively wide diffuse diffraction peak between 2θ = 40°-50°, the position and shape of the XRD spectrum peaks of the coating and the strip are highly consistent, which shows the typical amorphous characteristics. Figure 1 (c) is the TEM pattern of the iron-based amorphous coating, the disordered arrangement of atoms in the high-resolution TEM image and the diffuse halo in the selected area electron diffraction (SAED) indicate that the amorphous coating after spraying presents a completely amorphous structure.

[0045] Figure 2 is a flow chart for the preparation of the sealant in Example 1, first, the inorganic sealant is prepared, then the coating is immersed in the inorganic sealant to allow the inorganic sealant to penetrate into the coating pores, the coating is taken out after 35 min, and dried at room temperature for 2 h to obtain the inorganic sealing coating. Secondly, the organic sealant is prepared, the coating is immersed in the organic sealant for organic sealing, and surface modification is carried out, the immersion time is 50 min, and finally drying and curing treatment is carried out. The drying and curing treatment process is room temperature drying for 12 h.

[0046] Figure 3 is the SEM result of the untreated original coating and the sealed coating in Example 1. Figure 3 (a) and (c) are the surface and cross-section SEM images of the untreated original coating, respectively, Figure 3 (b) and (d) are the surface and cross-section SEM images of the sealed coating, respectively. The results show that the untreated original coating presents a rough and uneven surface and cross-section, and the rough surface is caused by the splashing and rebounding of the molten particles during the spraying process, so the original coating surface presents an uneven rough structure. After sealing, the coating surface is smooth and flat, the neodymium oxide deposited in the pore position is produced by inorganic sealing, and the organic resin can further seal the coating surface. The cross-section morphology also indirectly verifies this result, it can be found that the coating cross-section becomes more flat through sealing treatment. The SEM result shows that sealing plays an obvious filling role.

[0047] Figure 4 is the water jet experiment of the sealed coating in Example 1, the coating surface is covered with hydrophilic nano-powder pollutants, with the jet experiment, the pollutants on the surface of the coating roll down with the water flow, showing good antifouling property, the contact angle of the sealed coating is 156°, showing super-hydrophobicity.

[0048] Figure 5 is the electrochemical polarization curve of the sealed coating of Example 1. The test environment is a 3.5% mass concentration NaCl solution. It can be found that, compared with the original coating, the self-corrosion potential of the sealed iron-based amorphous coating is improved, and the self-corrosion current density is reduced by nearly three orders of magnitude, which shows that the sealing treatment can effectively improve the corrosion resistance of the coating.

[0049] Example 2

[0050] A sealing method of an iron-based amorphous coating, comprising the following steps:

[0051] The iron-based amorphous coating is prepared by using a high-velocity air fuel (HVAF) spraying technology to spray multiple times on the surface of a pretreated substrate to obtain an iron-based amorphous coating with a micron-level roughness; the composition of the iron-based amorphous alloy is as follows: Fe 50 Cr 18 Mo 7. 5Ni 3.5 P 12 B3C 3.5 Si 2.5 (at. % atomic ratio).

[0052] The HVAF high-velocity air fuel spraying process is to heat and melt the iron-based amorphous alloy powder with a particle size range of 40 μm and spray it onto the surface of the substrate or component;

[0053] The process parameters of the HVAF high-velocity air fuel spraying are as follows: air pressure 75 psi; propane gas pressure 70 psi; propane flow rate 125 SLPM; hydrogen flow rate 30 SLPM; nitrogen flow rate 30 SLPM; powder feeding rate 50 g / min; spraying distance 300 mm;

[0054] The obtained coating thickness is 400 μm.

[0055] (1) Coating surface treatment: cleaning the surface of the coating to be treated; the cleaning process is as follows: sequentially using acetone solution and deionized water to clean the coating, and finally using ethanol to clean the coating, and then naturally drying for 20 min.

[0056] (2) Preparation of inorganic sealing agent: dispersing 8 g of neodymium nitrate and 12 ml of hydrogen peroxide (mass concentration 30%) into 500 ml of deionized water and stirring for 35 min to obtain an inorganic sealing agent;

[0057] (3) Preparation of organic sealing agent: butyl acetate was added to bisphenol A type epoxy resin for dilution to obtain a mixed solution, the amount of butyl acetate added was 90% of the mass of the mixed solution; then 1H, 1H, 2H, 2H-perfluorodecyltriethylsilane (FDTES) was added to the mixed solution for surface modification, the amount of FDTES added was 2% of the mass of the organic sealing agent, and finally the organic sealing agent was obtained;

[0058] (4) Sealing treatment of the coating: the sealing method was immersion, the coating after surface treatment was first immersed in the inorganic rare earth sealing agent, the immersion time was 40 min, the inorganic sealing agent was allowed to penetrate into the pores of the coating, and a neodymium-based rare earth conversion film was formed on the surface of the coating, and the coating was taken out and dried in air at room temperature for 3 h.

[0059] Secondly, after inorganic sealing, the coating was immersed in the organic sealing agent for organic sealing and surface modification at the same time, the immersion time was 60 min, and finally drying and curing treatment was performed; the drying and curing treatment process was room temperature drying for 13 h, and finally the sealed coating was obtained.

[0060] Result analysis: in the DSC curve of Example 2, the ratio of the crystallization enthalpy ΔH of the coating and the strip sample was calculated to obtain the amorphous content of the coating as 99.2%, which was also close to complete amorphous. Through XRD analysis, the position and shape of the XRD spectrum peaks of the coating and the strip were highly consistent, showing typical amorphous characteristics. The TEM result of the coating was consistent with Example 1.

[0061] The preparation flow chart of the sealing agent in Example 2 was the same as that in Example 1. The difference was that in the preparation of the inorganic sealing agent, the coating was immersed in the inorganic sealing agent for 40 min, and the room temperature drying time was 3 h. In the preparation of the organic sealing agent, the coating was immersed in the organic sealing agent for 60 min, and finally the drying and curing treatment time was 13 h.

[0062] The SEM results of the untreated original coating and the sealed coating in Example 2 were consistent with those in Example 1.

[0063] The sealed coating in Example 2 was analyzed by water jet experiment, and the result also showed good self-cleaning property, and the contact angle of the sealed coating was as high as 158°, showing superhydrophobicity.

[0064] The electrochemical polarization curve of the sealed coating in Example 2. The test environment was also 3.5% NaCl solution, and the self-corrosion current density of the sealed iron-based amorphous coating was also reduced by nearly three orders of magnitude, indicating that the sealing treatment could effectively improve the corrosion resistance of the coating.

[0065] Comparative Example 1

[0066] To demonstrate the inventiveness of the claims of this invention, we performed a single inorganic sealing process, including the following steps:

[0067] The iron-based amorphous coating is prepared by multi-pass spraying on the surface of a pretreated substrate using high-velocity vapor deposition (HVAF) technology, resulting in an iron-based amorphous coating with micron-level roughness. The composition of the iron-based amorphous alloy is: Fe 50 Cr 18 Mo 7. 5Ni 3.5 P 12 B3C 3.5 Si 2.5 (at.% atomic ratio).

[0068] The HVAF supersonic flame spraying process involves heating and melting iron-based amorphous alloy powder with a particle size range of 45μm and spraying it onto the surface of a substrate or component.

[0069] The parameters for HVAF supersonic flame spraying are: air pressure 80 psi; propane pressure 80 psi; propane flow rate: 130 SLPM; hydrogen flow rate: 25 SLPM; nitrogen flow rate: 23 SLPM; powder feed rate: 60 g / min; spraying distance: 260 mm.

[0070] The obtained coating thickness is 400 μm.

[0071] (1) Coating surface treatment: Clean the coating surface to be treated; the cleaning process is as follows: use acetone solution and deionized water to clean the coating in sequence, and finally use ethanol to clean the coating. After cleaning, allow it to air dry for 20 minutes.

[0072] (2) Preparation of inorganic sealant: 5g neodymium nitrate and 10ml hydrogen peroxide (mass concentration 20%) were dispersed in 500ml deionized water and stirred for 35min to obtain inorganic sealant;

[0073] (3) The surface-treated coating is immersed in an inorganic rare earth sealing agent for 40 minutes, so that the inorganic sealing agent penetrates into the pores of the coating and forms a neodymium-based rare earth conversion film on the surface of the coating. The coating is then removed and dried in air at room temperature for 3 hours to finally obtain a single inorganic sealing coating.

[0074] Results Analysis: In Comparative Example 1, the contact angle of the single inorganic sealant coating is as follows: Figure 6 As shown, after a single inorganic seal, the contact angle results all exhibit hydrophilic behavior (water contact angle less than 90°), mainly because a large amount of neodymium oxide is deposited on the coating surface after the inorganic seal, and the oxide surface is rich in hydroxyl groups. A single inorganic seal does not achieve superhydrophobic behavior. The self-cleaning performance does not reach the levels of Examples 1 and 2.

[0075] As shown in the polarization curve results, the corrosion resistance of the single inorganic post-sealing coating was improved by nearly one order of magnitude, but the performance still did not reach the effect of Examples 1 and 2. Figure 7

[0076] Comparative Example 2

[0077] In order to prove the inventiveness of the claims of the present application, we carried out a single organic sealing treatment, including the following steps:

[0078] The iron-based amorphous coating is prepared by using a high-velocity air flow (HVAF) technique to spray the surface of the pretreated substrate in multiple passes to form an iron-based amorphous coating with a micron-level roughness; the composition of the iron-based amorphous alloy is as follows: Fe 50 Cr 18 Mo 7. 5Ni 3.5 P 12 B3C 3.5 Si 2.5 (at. % atomic ratio).

[0079] The HVAF high-velocity air flow spraying process is to heat and melt the iron-based amorphous alloy powder with a particle size range of 45 μm and spray it onto the surface of the substrate or component;

[0080] The process parameters of the HVAF high-velocity air flow spraying are as follows: air pressure 80 psi; propane gas pressure 80 psi; propane flow rate 130 SLPM; hydrogen flow rate 25 SLPM; nitrogen flow rate 23 SLPM; powder feeding rate 60 g / min; spraying distance 260 mm;

[0081] The obtained coating thickness is 400 μm.

[0082] (1) Coating surface treatment: the surface of the coating to be treated is cleaned; the cleaning process is as follows: the coating is cleaned with acetone solution and deionized water in sequence, and finally cleaned with ethanol, and then naturally dried for 20 min.

[0083] (2) Butyl acetate is added to the bisphenol A type epoxy resin to obtain a mixed solution, and the addition amount of butyl acetate is 90% of the mass of the mixed solution; then 1H, 1H, 2H, 2H-perfluorodecyltriethylsilane (FDTES) is added to the mixed solution for surface modification, and the addition amount of FDTES is 2% of the mass of the organic sealing agent, and finally the organic sealing agent is obtained.

[0084] ​(3) The coating is immersed in an organic sealant for organic sealing while achieving surface modification, the immersion time is 60 min, and finally a drying and curing treatment is performed; the drying and curing treatment process is room temperature drying for 13 h, and finally a single organic sealing coating is obtained.

[0085] Result analysis: under Comparative Example 2, the contact angle of the single organic sealing coating is as shown in Figure 6 The contact angle result shows hydrophobic behavior (water contact angle between 90° and 150°) after single organic sealing, and single organic sealing does not achieve super-hydrophobic behavior. The self-cleaning performance does not reach the effect of Examples 1 and 2.

[0086] Under Comparative Example 1, the electrochemical result of the single organic sealing coating is as shown in Figure 7 The polarization curve result shows that although the corrosion resistance of the single organic sealing coating is improved, it is only improved by nearly one order of magnitude, and the performance still does not reach the effect of Examples 1 and 2.

Claims

1. An iron-based amorphous alloy coating sealing process, characterized in that, The method comprises the following steps: (1) coating surface treatment: cleaning the surface of the coating to be treated; (2) preparation of inorganic sealing agent: dispersing 5-10 g of neodymium nitrate and 10-15 ml of hydrogen peroxide with a mass concentration of 10-30% into 500 ml of deionized water, and stirring to obtain an inorganic sealing agent; (3) preparation of organic sealing agent: adding butyl acetate to the epoxy resin to dilute and obtain a mixed solution, the addition amount of butyl acetate being 75%-95% of the mass of the mixed solution; then adding 1H, 1H, 2H, 2H-perfluorodecyltriethylsilane (FDTES) into the mixed solution for surface modification, the addition amount of FDTES being 1%-3% of the mass of the organic sealing agent, and finally obtaining the organic sealing agent; (4) sealing treatment of the coating: the sealing method is immersion, the coating is first immersed in the inorganic rare earth sealing agent, dried, then immersed in the organic sealing agent, and dried and solidified to obtain a sealed coating.

2. The sealing process according to claim 1, wherein: in step (2), 5-8 g of neodymium nitrate and 10-12 ml of hydrogen peroxide with a mass concentration of 10-30% are dispersed into 500 ml of deionized water, and stirred to obtain an inorganic sealing agent.

3. The sealing process according to claim 1, wherein: the HVAF supersonic flame spraying process is to heat and melt the iron-based amorphous alloy powder with a particle size range of 18-53 μm and spray it onto the surface of the substrate or member; the HVAF supersonic flame spraying process parameters are: air pressure 70-90 psi; propane gas pressure 70-95 psi; propane flow rate: 90-160 SLPM; hydrogen flow rate: 10-40 SLPM; nitrogen flow rate: 10-30 SLPM; powder feeding rate: 40-70 g / min; spraying distance: 200-350 mm; The iron-based amorphous coating is prepared by using a high-velocity air fuel (HVAF) technique to spray multiple passes on the surface of a pretreated substrate to obtain an iron-based amorphous coating with a micron-level roughness; the iron-based amorphous alloy composition, in terms of atomic percentage, is as follows: Fe 余量 Cr 18-21 Mo 5-9 Ni 2-5 P 9-15 B 1-5 C 2-6 Si 1-5 ; the obtained coating thickness is between 400-500 μm.

4. The sealing process according to claim 3, wherein: the HVAF supersonic flame spraying process parameters are: air pressure 75-85 psi; propane gas pressure 75-90 psi; propane flow rate: 110-150 SLPM; hydrogen flow rate: 20-30 SLPM; nitrogen flow rate: 15-25 SLPM; powder feeding rate: 45-65 g / min; spraying distance: 220-300 mm. In step (1), the cleaning process is: sequentially using acetone solution and deionized water to clean the coating, and finally using ethanol to clean the coating, and then naturally drying for more than 5 min. After cleaning, naturally dry for 10-30 min. In step (2), the stirring time is more than 5 min.

5. The hole sealing process of claim 1, wherein: In step (2), the stirring time is 20-40 min.

6. The hole sealing process of claim 5, wherein: In step (3), the epoxy resin is bisphenol A type epoxy resin.

7. The hole sealing process of claim 1, wherein: In step (4), the sealing method is immersion.

8. The hole sealing process of claim 7, wherein: ​ 9. The hole sealing process of claim 1, wherein: ​ 10. The hole sealing process of claim 1, wherein: ​ Firstly, the coating after surface treatment is immersed in inorganic rare earth sealing agent, the immersion time is 10-50 min, so that the inorganic sealing agent penetrates into the coating pores, and a neodymium-based rare earth conversion film is formed on the surface of the coating, the coating is taken out, and dried in air at room temperature for 1-6 h; Secondly, after inorganic sealing, the coating is immersed in organic sealing agent for organic sealing and surface modification, the immersion time is 20-100 min, and finally drying and curing treatment is carried out; the drying and curing treatment process is drying at room temperature for 8-24 h, and finally a sealed coating is obtained.

11. The hole sealing process of claim 10, wherein: In step (4), the sealing method is immersion method: Firstly, the coating after surface treatment is immersed in inorganic rare earth sealing agent, the immersion time is 15-45 min, so that the inorganic sealing agent penetrates into the coating pores, and a neodymium-based rare earth conversion film is formed on the surface of the coating, the coating is taken out, and dried in air at room temperature for 2-5 h; Secondly, after inorganic sealing, the coating is immersed in organic sealing agent for organic sealing and surface modification, the immersion time is 40-80 min, and finally drying and curing treatment is carried out; the drying and curing treatment process is drying at room temperature for 10-16 h, and finally a sealed coating is obtained.

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