A method for surface corrosion protection of sintered NdFeB magnets
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-06-26
- Publication Date
- 2026-08-14
AI Technical Summary
但是，高温环境（>150℃）会导致传统有机涂层软化、脱附，使腐蚀介质渗透
本发明提供了一种烧结钕铁硼磁体表面防腐处理方法，与传统电镀工艺相比，通过在超高真空环境下采用分子束外延技术对烧结钕铁硼磁体表面进行低温镀膜处理，解决了传统电镀工艺高温导致磁性能退化的问题，保持了烧结钕铁硼磁体的原有磁性能；通过形成Al2O3和SiO2无机底层和聚二甲基硅氧烷(PDMS)/ TiO2纳米复合有机顶层的双层复合防腐膜结构，实现物理阻隔与化学钝化的协同防腐，显著提高了防腐性能，提供了更优异的防腐保护效果。此外，本发明还具有防腐膜层厚度薄、界面结合力强等优点，制得的高性能防腐烧结钕铁硼磁体能够满足航空航天、风力发电、新能源汽车等高端产业的严苛使用需求。
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of rare earth permanent magnet materials technology, and particularly relates to a method for surface anti-corrosion treatment of sintered NdFeB magnets. Background Technology
[0002] Neodymium iron boron (NdFeB) permanent magnets, renowned as the "King of Magnets" due to their superior magnetic properties such as high energy product, high coercivity, and high remanence, are widely used in motors, electronic equipment, medical devices, and clean energy. However, their inherent defects, including high chemical reactivity, large potential difference in their multiphase structure, and susceptibility to corrosion at grain boundaries, severely limit their reliable application in harsh environments. Therefore, effective surface anti-corrosion treatment of sintered NdFeB magnets is a key technology for improving their service life and reliability.
[0003] Currently, surface corrosion protection technologies for NdFeB magnets mainly include electroplating, chemical conversion coatings (such as passivation and phosphating), and organic coatings. Electroplating is the most widely used surface corrosion protection technology, primarily enhancing corrosion resistance, oxidation resistance, and surface hardness by isolating the magnet from oxygen in the air. Electroplating materials mainly include nickel, zinc, copper, and tin. However, electroplating processes suffer from problems such as thermal stress leading to magnetic property degradation, large film thickness, and numerous and complex steps. Chemical conversion coating technology mainly includes passivation and phosphating, offering advantages such as simple processes and low cost. However, chemical conversion coating technology also faces the challenge of high-temperature pretreatment, which may affect magnetic properties. While organic coating technology can improve the corrosion resistance and wear resistance of magnets and provide diverse color options, high-temperature environments (>150℃) can cause traditional organic coatings to soften and desorb, allowing corrosive media to penetrate. Therefore, improving the corrosion resistance of sintered NdFeB magnets in low-temperature environments is crucial. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a surface anti-corrosion treatment method for sintered NdFeB magnets based on molecular beam epitaxy (MBE) technology. This method makes up for the shortcomings of the prior art by performing atomic-level low-temperature coating treatment on the surface of sintered NdFeB magnets in an ultra-high vacuum environment using molecular beam epitaxy technology to form a strong double-layer composite anti-corrosion film structure. This solves the problem of magnetic performance degradation caused by high temperature in traditional electroplating processes and improves the anti-corrosion performance.
[0005] To address the aforementioned technical problems, this invention provides a method for surface corrosion protection of sintered NdFeB magnets, comprising the following steps: S1. The sintered NdFeB magnet is placed in an ultra-high vacuum environment and the magnet surface is activated by Ar plasma to form an active surface, thus obtaining NdFeB magnet 1. S2. The neodymium iron boron magnet 1 is heated, and Al2O3 and SiO2 are sequentially deposited on the surface of the magnet by molecular beam epitaxy to form an inorganic bottom layer, thereby obtaining neodymium iron boron magnet 2. S3. Using a mixed gas plasma containing O2 and Ar, a composite organic top layer composed of polydimethylsiloxane and nano-TiO2 is deposited on the surface of the NdFeB magnet 2 to form a superhydrophobic surface and obtain a corrosion-resistant high-performance sintered NdFeB magnet.
[0006] In the above-described method for surface corrosion protection of sintered NdFeB magnets, further, in step S1, the ultra-high vacuum environment has a pressure ≥1×10⁻⁶. -10 Torr; The power used for the Ar plasma activation treatment of the magnet surface is 1 W to 500 W, and the time is 1 min to 100 mins.
[0007] In the above-mentioned method for surface anti-corrosion treatment of sintered NdFeB magnets, in step S2, the NdFeB magnet 1 is heated to 10 ℃~500 ℃.
[0008] In the above-mentioned method for surface anti-corrosion treatment of sintered NdFeB magnets, in step S2, during the process of sequentially depositing Al2O3 and SiO2 on the magnet surface using molecular beam epitaxy, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating of the entire surface.
[0009] In the above-mentioned method for surface corrosion protection of sintered NdFeB magnets, the molecular beam intensity is further controlled to be 0.01 Å / s ~ 0.99 Å / s.
[0010] In the above-mentioned method for surface anti-corrosion treatment of sintered NdFeB magnets, the thickness of the inorganic substrate in S2 is 1 nm to 1000 nm.
[0011] In the above-mentioned method for surface anti-corrosion treatment of sintered NdFeB magnets, further, in step S3, during the deposition of the composite organic top layer, the sintered NdFeB magnet is controlled to rotate in multiple axes to achieve uniform coating of the entire surface.
[0012] In the above-mentioned method for surface corrosion protection of sintered NdFeB magnets, the plasma-assisted deposition power is 1 W to 500 W and the deposition time is 1 min to 100 mins.
[0013] In the above-mentioned method for surface anti-corrosion treatment of sintered NdFeB magnets, the thickness of the dimethylsiloxane / TiO2 nanocomposite organic top layer in S3 is 1 nm to 1000 nm.
[0014] In the above-mentioned method for surface anti-corrosion treatment of sintered NdFeB magnets, the mass ratio of polydimethylsiloxane to deposited TiO2 in the composite organic top layer is 1:1 to 100:1.
[0015] Compared with the prior art, the advantages of the present invention are as follows: This invention provides a method for surface anti-corrosion treatment of sintered NdFeB magnets. Compared with traditional electroplating processes, this method utilizes molecular beam epitaxy technology in an ultra-high vacuum environment to perform low-temperature coating treatment on the surface of sintered NdFeB magnets, solving the problem of magnetic property degradation caused by high temperatures in traditional electroplating processes and maintaining the original magnetic properties of the sintered NdFeB magnets. By forming a double-layer composite anti-corrosion film structure consisting of an inorganic Al2O3 and SiO2 bottom layer and a polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer, synergistic anti-corrosion through physical barrier and chemical passivation is achieved, significantly improving anti-corrosion performance and providing superior anti-corrosion protection. Furthermore, this invention also has advantages such as thin anti-corrosion film thickness and strong interfacial adhesion, resulting in high-performance anti-corrosion sintered NdFeB magnets that can meet the stringent requirements of high-end industries such as aerospace, wind power generation, and new energy vehicles. Attached Figure Description
[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.
[0017] Figure 1 This is a flowchart of a method for surface anti-corrosion treatment of sintered NdFeB magnets according to the present invention. Detailed Implementation
[0018] The present invention will be further described below with reference to specific preferred embodiments, but this does not limit the scope of protection of the present invention. The materials, reagents, and instruments used in the following embodiments can all be purchased commercially. Unless otherwise specified, the experimental methods in the following embodiments are conventional methods in the art.
[0019] This invention discloses a method for surface corrosion protection of sintered NdFeB magnets, the process of which is as follows: Figure 1 As shown, the specific process is as follows: Step 1: Place the sintered NdFeB magnet in an ultra-high vacuum (≥1×10⁻⁶). -10 In a Torr environment, the magnet surface is activated by Ar plasma to form an active surface, thus obtaining a neodymium iron boron magnet 1.
[0020] Specifically, the power used for Ar plasma activation treatment of the magnet surface is 1 W to 500 W, and the time is 1 min to 100 mins. Further, the power used is 20 W to 70 W, and the time is 5 mins to 20 mins.
[0021] Utilizing an ultra-vacuum environment reduces the oxygen and carbon content on the surface, allowing for the removal of surface oil, dust, and adsorbed water, and the stripping of the natural Nd / Fe oxide layer. The magnet surface is then activated using 1 W to 500 W Ar plasma, generating numerous dangling bonds, defects, and free radicals, significantly increasing surface energy. Further, 40 W to 100 W Ar plasma is used to activate the magnet surface.
[0022] Step 2: After heating the NdFeB magnet 1 to a certain temperature, Al2O3 and SiO2 are sequentially deposited on the magnet surface using molecular beam epitaxy. During the deposition process, the sintered NdFeB magnet is controlled to rotate in multiple axes to achieve uniform coating of the entire surface and form an inorganic bottom layer, thus obtaining the NdFeB magnet 2.
[0023] Specifically, the temperature of the heated magnet is 10 ℃ to 500 ℃; the molecular beam intensity is controlled at 0.01 Å / s to 0.99 Å / s; and the thickness of the formed inorganic substrate is 1 nm to 1000 nm. Further, the temperature of the heated magnet is 10 ℃ to 500 ℃; the molecular beam intensity is controlled at 0.01 Å / s to 0.10 Å / s; and the thickness of the inorganic substrate is 10 nm to 100 nm.
[0024] Molecular beam epitaxy technology was used to perform low-temperature coating treatment on the surface of sintered NdFeB magnets to form an inorganic underlayer of Al2O3 and SiO2. This solved the problem of magnetic property degradation caused by high temperature in traditional electroplating processes and maintained the original magnetic properties of sintered NdFeB magnets.
[0025] Step 3: On the surface of NdFeB magnet 2, a polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer is deposited using O2 / Ar mixed gas plasma-assisted deposition. During the deposition process, the sintered NdFeB magnet is controlled to rotate in multiple axes to achieve uniform coating of the entire surface, forming a superhydrophobic surface, and obtaining a corrosion-resistant high-performance sintered NdFeB magnet.
[0026] Specifically, the plasma-assisted deposition power is 1 W to 500 W, the deposition time is 1 min to 100 mins, the organic top layer thickness is 1 nm to 1000 nm, and the mass ratio of deposited polydimethylsiloxane (PDMS) to deposited TiO2 is 1:1 to 100:1.
[0027] Furthermore, the plasma-assisted deposition power is 10 W to 50 W, the deposition time is 5 mins to 20 mins, and the thickness of the organic top layer is 10 nm to 30 nm.
[0028] By forming a double-layer composite anti-corrosion film structure consisting of an inorganic bottom layer of Al2O3 and SiO2 and an organic top layer of polydimethylsiloxane (PDMS) / TiO2 nanocomposite, synergistic anti-corrosion through physical barrier and chemical passivation is achieved, significantly improving anti-corrosion performance and providing superior anti-corrosion protection.
[0029] The present invention will now be described in detail with reference to several specific embodiments.
[0030] Example 1 A method for surface corrosion protection of sintered NdFeB magnets, comprising the following specific steps: Step 1: Place the sintered NdFeB magnet in an ultra-high vacuum (≥1×10⁻⁶). -10 In a Torr environment, the magnet surface was activated by Ar plasma to form an active surface, thus obtaining a NdFeB magnet 1. The power used for Ar plasma activation of the magnet surface was 50 W, and the time was 10 mins.
[0031] Step 2: After heating the NdFeB magnet 1 to 60 °C, Al2O3 and SiO2 are sequentially deposited on the magnet surface using molecular beam epitaxy with the molecular beam intensity controlled at 0.06 Å / s. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating of the entire surface, forming a gradient inorganic underlayer with a thickness of 50 nm, thus obtaining the NdFeB magnet 2.
[0032] Step 3: On the surface of NdFeB magnet 2, a 20 nm thick polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer is deposited using O2 / Ar mixed gas plasma-assisted deposition. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating across the entire surface, forming a superhydrophobic surface and obtaining a corrosion-resistant, high-performance sintered NdFeB magnet. The plasma-assisted deposition power is 30 W, the deposition time is 10 mins, and the mass ratio of deposited PDMS to deposited TiO2 is 10:1.
[0033] Example 2 A method for surface corrosion protection of sintered NdFeB magnets, comprising the following specific steps: Step 1: Place the sintered NdFeB magnet in an ultra-high vacuum (≥1×10⁻⁶). -10In a Torr environment, the magnet surface was activated by Ar plasma to form an active surface, thus obtaining a NdFeB magnet 1. The power used for Ar plasma activation of the magnet surface was 50 W, and the time was 10 mins.
[0034] Step 2: After heating the NdFeB magnet 1 to 10 °C, Al2O3 and SiO2 are sequentially deposited on the magnet surface using molecular beam epitaxy with the molecular beam intensity controlled at 0.06 Å / s. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating of the entire surface, forming a gradient inorganic underlayer with a thickness of 50 nm, thus obtaining the NdFeB magnet 2.
[0035] Step 3: On the surface of NdFeB magnet 2, a 20 nm thick polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer is deposited using O2 / Ar mixed gas plasma-assisted deposition. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating across the entire surface, forming a superhydrophobic surface and obtaining a corrosion-resistant, high-performance sintered NdFeB magnet. The plasma-assisted deposition power is 30 W, the deposition time is 10 mins, and the mass ratio of deposited PDMS to deposited TiO2 is 10:1.
[0036] Example 3 A method for surface corrosion protection of sintered NdFeB magnets, comprising the following specific steps: Step 1: Place the sintered NdFeB magnet in an ultra-high vacuum (≥1×10⁻⁶). -10 In a Torr environment, the magnet surface was activated by Ar plasma to form an active surface, thus obtaining a NdFeB magnet 1. The power used for Ar plasma activation of the magnet surface was 50 W, and the time was 10 mins.
[0037] Step 2: After heating the NdFeB magnet 1 to 500 ℃, Al2O3 and SiO2 are sequentially deposited on the magnet surface using molecular beam epitaxy with the molecular beam intensity controlled at 0.06 Å / s. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating of the entire surface, forming a gradient inorganic underlayer with a thickness of 50 nm, thus obtaining the NdFeB magnet 2.
[0038] Step 3: On the surface of NdFeB magnet 2, a 20 nm thick polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer is deposited using O2 / Ar mixed gas plasma-assisted deposition. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating across the entire surface, forming a superhydrophobic surface and obtaining a corrosion-resistant, high-performance sintered NdFeB magnet. The plasma-assisted deposition power is 30 W, the deposition time is 10 mins, and the mass ratio of deposited PDMS to deposited TiO2 is 10:1.
[0039] Example 4 A method for surface corrosion protection of sintered NdFeB magnets, comprising the following specific steps: Step 1: Place the sintered NdFeB magnet in an ultra-high vacuum (≥1×10⁻⁶). -10 In a Torr environment, the magnet surface was activated by Ar plasma to form an active surface, thus obtaining a NdFeB magnet 1. The power used for Ar plasma activation of the magnet surface was 50 W, and the time was 10 mins.
[0040] Step 2: After heating the NdFeB magnet 1 to 60 °C, Al2O3 and SiO2 are sequentially deposited on the magnet surface using molecular beam epitaxy with the molecular beam intensity controlled at 0.06 Å / s. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating of the entire surface, forming a gradient inorganic underlayer with a thickness of 50 nm, thus obtaining the NdFeB magnet 2.
[0041] Step 3: On the surface of NdFeB magnet 2, a 20 nm thick polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer is deposited using O2 / Ar mixed gas plasma-assisted deposition. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating across the entire surface, forming a superhydrophobic surface and obtaining a corrosion-resistant, high-performance sintered NdFeB magnet. The plasma-assisted deposition power is 30 W, the deposition time is 10 mins, and the mass ratio of deposited PDMS to deposited TiO2 is 1:1.
[0042] Example 5 A method for surface corrosion protection of sintered NdFeB magnets, comprising the following specific steps: Step 1: Place the sintered NdFeB magnet in an ultra-high vacuum (≥1×10⁻⁶). -10 In a Torr environment, the magnet surface was activated by Ar plasma to form an active surface, thus obtaining a NdFeB magnet 1. The power used for Ar plasma activation of the magnet surface was 50 W, and the time was 10 mins.
[0043] Step 2: After heating the NdFeB magnet 1 to 60 °C, Al2O3 and SiO2 are sequentially deposited on the magnet surface using molecular beam epitaxy with the molecular beam intensity controlled at 0.06 Å / s. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating of the entire surface, forming a gradient inorganic underlayer with a thickness of 50 nm, thus obtaining the NdFeB magnet 2.
[0044] Step 3: On the surface of NdFeB magnet 2, a 20 nm thick polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer is deposited using O2 / Ar mixed gas plasma-assisted deposition. During the deposition process, the sintered NdFeB magnet is controlled to undergo multi-axis rotation to achieve uniform coating across the entire surface, forming a superhydrophobic surface and obtaining a corrosion-resistant, high-performance sintered NdFeB magnet. The plasma-assisted deposition power is 30 W, the deposition time is 10 mins, and the mass ratio of deposited PDMS to deposited TiO2 is 100:1.
[0045] Comparative Example 1 Steps 1 and 2 of the method in Example 1 are used, but step 3 is omitted.
[0046] Comparative Example 2 Steps 1 and 3 of the method in Example 1 are used, with step 2 omitted.
[0047] Comparative Example 3 Steps 2 and 3 of the method in Example 1 are used, with step 1 omitted.
[0048] Comparative Example 4 The sintered NdFeB magnets are surface-treated for corrosion protection using a traditional nickel electroplating process. The specific process involves immersing the magnet in an electroplating solution containing nickel sulfate and nickel chloride, applying an electric current for electroplating, controlling the electroplating temperature at 80℃~100℃, and maintaining the plating time at 30~60 minutes to achieve a plating thickness of 10 μm~20 μm. After electroplating, the magnets undergo drying.
[0049] Comparative Example 5 The chemical conversion coating technology is employed, specifically chromate passivation treatment. The specific process is as follows: First, the magnet is surface-cleaned and activated at 100~150℃, then placed in a chromate solution and treated at 80~100℃ for 10~30 minutes to form a conversion coating with a thickness of 0.1μm~1μm.
[0050] Comparative Example 6 Epoxy resin was used as an organic coating for surface treatment of sintered NdFeB magnets. The specific process was as follows: an epoxy resin solution was uniformly coated on the magnet surface, and then cured at 120~150 ℃ for 30~60 minutes, with a coating thickness of 5 μm~10 μm.
[0051] Comparative Example 7 A film was deposited on the surface of sintered NdFeB magnets using magnetron sputtering technology. The specific process involved: depositing a film under a vacuum of 10... -3 Under Torr conditions, using an Al2O3 target, sputtering power of 100~500 W, substrate temperature controlled at 100~300 ℃, and sputtering time of 30~60 minutes, an Al2O3 film with a thickness of 100~500 nm is formed.
[0052] In the embodiments and comparative examples of this invention, the magnets used in the experiments were all industrial sintered NdFeB magnets N38 samples (with a coercivity of 12.5 kOe at 20°C); other undisclosed reagents were all commercially available.
[0053] The corrosion-resistant sintered NdFeB magnets prepared in Examples 1-5 and Comparative Examples 1-7 were used as samples for performance testing. The test results are listed in Table 1.
[0054] Corrosion resistance test: According to GB / T10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", the test sample is placed in a salt spray chamber and sprayed continuously with 5% NaCl solution (pH 6.5-7.2) at a temperature of 35 ℃. The time when the first rust point appears on the sample surface is observed, which is the salt spray resistance time.
[0055] Coating adhesion test: According to GB / T 9286-2021 "Paints and Varnishes - Cross-cut Test", a 10×10 grid (1 mm per grid) is drawn on the coating surface using a cross-cut knife. 2 After peeling off the tape, observe the coating peeling off within the grid and rate it from 0 to 5, where 0 means no peeling and 5 means complete peeling.
[0056] Coercivity test: According to GB / T 3217-2013 Magnetic test method for permanent magnet (hard magnet) materials, the coercivity performance of all samples at 20 ℃ after the first rust point appears on the surface was tested using the NIM-6500C ultra-high temperature permanent magnet measurement system.
[0057] Table 1: Test Results of Corrosion-Resistant Sintered NdFeB Magnets
[0058]
[0059] The results in Table 1 show that Example 1 exhibits the best corrosion resistance and adhesion, while also experiencing the least loss of magnetic properties. A comparison of Examples 1, 2, and 3 reveals the influence of the magnet substrate temperature during molecular beam epitaxy coating on the magnet's corrosion resistance and magnetic properties. A comparison of Examples 1, 4, and 5 demonstrates the effect of the mass ratio of deposited polydimethylsiloxane (PDMS) to deposited TiO2 on the magnet's corrosion resistance and magnetic properties. A comparison of Examples 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3 shows that by employing molecular beam epitaxy technology in an ultra-high vacuum environment to perform low-temperature coating treatment on the surface of sintered NdFeB magnets and by forming a double-layer composite anti-corrosion film structure consisting of an inorganic Al2O3 and SiO2 underlayer and a polydimethylsiloxane (PDMS) / TiO2 nanocomposite organic top layer, magnetic property loss is significantly reduced, providing superior anti-corrosion protection and strong interfacial adhesion. By comparing Examples 1, 4, 5, 6 and 7, it can be seen that, compared with traditional anti-corrosion processes, the anti-corrosion method of the present invention exhibits excellent anti-corrosion performance and greatly reduces the loss of magnetic properties.
[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the spirit and technical essence of the present invention. Therefore, any simple modifications, equivalent substitutions, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall still fall within the protection scope of the technical solutions of the present invention.
Claims
1. A method for surface anti-corrosion treatment of sintered NdFeB magnets, characterized in that, Includes the following steps: S1. The sintered NdFeB magnet is placed in an ultra-high vacuum environment and the magnet surface is activated by Ar plasma to form an active surface, thus obtaining NdFeB magnet 1. S2. The neodymium iron boron magnet 1 is heated, and Al2O3 and SiO2 are sequentially deposited on the surface of the magnet by molecular beam epitaxy to form an inorganic bottom layer, thereby obtaining neodymium iron boron magnet 2. S3. Using a mixed gas plasma containing O2 and Ar, a composite organic top layer composed of polydimethylsiloxane and nano-TiO2 is deposited on the surface of the NdFeB magnet 2 to form a superhydrophobic surface and obtain a corrosion-resistant high-performance sintered NdFeB magnet.
2. The method for surface corrosion protection of sintered NdFeB magnets according to claim 1, characterized in that, In S1, the ultra-high vacuum environment is a pressure ≥ 1 × 10⁻⁶. -10 Torr; The power used for the Ar plasma activation treatment of the magnet surface is 1W~500W, and the time is 1min~100mins.
3. The method for surface corrosion protection of sintered NdFeB magnets according to claim 1, characterized in that, In step S2, the neodymium iron boron magnet 1 is heated to 10 ℃~500 ℃.
4. The surface corrosion protection method for sintered NdFeB magnets according to claim 1, characterized in that, In step S2, during the process of sequentially depositing Al2O3 and SiO2 on the magnet surface using molecular beam epitaxy, the sintered NdFeB magnet is controlled to rotate in multiple axes to achieve uniform coating of the entire surface.
5. The method for surface corrosion protection of sintered NdFeB magnets according to claim 4, characterized in that, The molecular beam intensity was controlled at 0.01 Å / s ~ 0.99 Å / s.
6. The method for surface corrosion protection of sintered NdFeB magnets according to claim 1, characterized in that, The thickness of the inorganic substrate in S2 is 1 nm to 1000 nm.
7. The method for surface corrosion protection of sintered NdFeB magnets according to claim 1, characterized in that, In step S3, during the deposition of the composite organic top layer, the sintered NdFeB magnet is controlled to rotate in multiple axes to achieve uniform coating of the entire surface.
8. The method for surface corrosion protection of sintered NdFeB magnets according to claim 7, characterized in that, The power of plasma-assisted deposition ranges from 1 W to 500 W, and the deposition time ranges from 1 min to 100 mins.
9. The method for surface corrosion protection of sintered NdFeB magnets according to claim 1, characterized in that, The thickness of the dimethylsiloxane / TiO2 nanocomposite organic top layer in S3 is 1 nm to 1000 nm.
10. The method for surface corrosion protection of sintered NdFeB magnets according to claim 1, characterized in that, In the composite organic top layer, the mass ratio of polydimethylsiloxane to deposited TiO2 is 1:1 to 100:1.