A method for manufacturing a magnetic powder core

Abstract

The application belongs to the technical field of electronic devices, and particularly relates to a preparation method of a magnetic powder core. The application provides a preparation method of a magnetic powder core, which comprises the following steps: providing a preformed component of nanocrystalline alloy magnetic powder; under the action of a supergravity field, flowing liquid insulation material into the preformed component of nanocrystalline alloy magnetic powder, and obtaining the magnetic powder core through solidification. The application utilizes the supergravity infiltration process, can realize the uniform distribution of nanocrystalline alloy magnetic powder and liquid insulation material, improves the effective permeability of the magnetic powder core, and can realize the complete coating of the liquid insulation material on the nanocrystalline alloy magnetic powder, so that the obtained magnetic powder core has higher resistivity and wide-frequency constant inductance characteristics.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electronic devices, and particularly relates to a preparation method of a magnetic powder core. BACKGROUND

[0002] The magnetic powder core has excellent wide-frequency constant inductance characteristics, i.e. the inductance value change is small in a wide frequency range, and the loss is low at high frequency, and meanwhile has excellent DC bias performance. Due to the excellent performance, the magnetic powder core is widely applied to various inductance devices. With the development of electronic components towards miniaturization, high frequency, low loss and high power, higher requirements are put forward for the magnetic powder core. The nanocrystalline alloy has extremely high permeability and resistivity, and is easy to be broken into powder after crystallization annealing, and thus is expected to be used for preparing the magnetic powder core with excellent performance.

[0003] The preparation process of the magnetic powder core mainly includes powder preparation, screening, insulation coating, pressing, heat treatment, resin reinforcement or paint spraying. For the iron-based nanocrystalline alloy raw material, the preparation process is to first prepare an amorphous alloy ribbon, then perform crystallization annealing to obtain a nanocrystalline alloy ribbon, and then break the nanocrystalline alloy ribbon to obtain a powder. The iron-based nanocrystalline alloy powder prepared from the ribbon is in a flaky shape rather than a spherical shape.

[0004] The traditional insulation coating process is usually to coat the nanocrystalline alloy with an insulating agent through chemical reaction or physical mixing. Due to the surface tension, it is difficult to achieve coating at the sharp corners of the flaky powder, which affects the wide-frequency constant inductance characteristics of the magnetic powder core. In addition, the uneven distribution of the nanocrystalline alloy and the insulating agent leads to low permeability of the magnetic powder core. SUMMARY

[0005] The present application aims to provide a preparation method of a magnetic powder core. The method provided by the present application can obtain a magnetic powder core with excellent wide-frequency constant inductance characteristics and high permeability.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0007] The present application provides a preparation method of a magnetic powder core, comprising the following steps:

[0008] providing a preformed component of nanocrystalline alloy magnetic powder;

[0009] under the action of a supergravity field, flowing a liquid insulating material into the preformed component of nanocrystalline alloy magnetic powder, and obtaining the magnetic powder core after solidification.

[0010] Preferably, the gravity of the supergravity field is 1000-3000g.

[0011] Preferably, the nanocrystalline alloy magnetic powder has a mesh size of ≥100 mesh.

[0012] Preferably, the nanocrystalline alloy magnetic powder comprises at least one of small-particle-size nanocrystalline alloy, medium-particle-size nanocrystalline alloy and large-particle-size nanocrystalline alloy;

[0013] The mesh number M1 of the large-particle-size nanocrystalline alloy magnetic powder is 100 mesh≤M1≤200 mesh;

[0014] The mesh number M2 of the medium-particle-size nanocrystalline alloy magnetic powder is 200 mesh

[0015] The mesh number M3 of the small-particle-size nanocrystalline alloy magnetic powder is M3>400 mesh.

[0016] Preferably, when the nanocrystalline alloy magnetic powder is any two of small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder and large-particle-size nanocrystalline alloy magnetic powder;

[0017] The mass ratio of the small-particle-size nanocrystalline alloy magnetic powder and the medium-particle-size nanocrystalline alloy magnetic powder is 1:2.3-9;

[0018] The mass ratio of the small-particle-size nanocrystalline alloy magnetic powder and the large-particle-size nanocrystalline alloy magnetic powder is 1:2-9;

[0019] The mass ratio of the medium-particle-size nanocrystalline alloy magnetic powder and the large-particle-size nanocrystalline alloy magnetic powder is 1:1-9.

[0020] Preferably, when the nanocrystalline alloy magnetic powder is small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder and large-particle-size nanocrystalline alloy magnetic powder, the mass ratio of the small-particle-size nanocrystalline alloy magnetic powder, the medium-particle-size nanocrystalline alloy magnetic powder and the large-particle-size nanocrystalline alloy magnetic powder is 1:1-3:1-8.

[0021] Preferably, the viscosity of the liquid insulation material is <13000 mPa·s.

[0022] Preferably, the mass ratio of the liquid insulation material and the nanocrystalline alloy magnetic powder is 1:8-12.

[0023] Preferably, the pore size in the preform of the nanocrystalline alloy magnetic powder is 1-50 μm;

[0024] The time of the infiltration is ≥3 min.

[0025] Preferably, the temperature of the solidification is room temperature, and the time is ≥24 h.

[0026] The application provides a preparation method of a magnetic powder core, comprising the following steps: providing a preformed component of nanocrystalline alloy magnetic powder; under the action of a supergravity field, causing liquid insulation material to infiltrate into the preformed component of nanocrystalline alloy magnetic powder, and obtaining the magnetic powder core after solidification. The application firstly constructs a magnetic powder structure with pores, and then causes the insulation agent to uniformly infiltrate and coat the magnetic powder in a short time under the action of supergravity. The application can realize the uniform distribution of nanocrystalline alloy and liquid insulation material by using the supergravity infiltration process, improve the effective permeability of the magnetic powder core, can realize the uniform coating and complete coating of the liquid insulation material on the nanocrystalline alloy with a sheet structure, and can make the nanocrystalline alloy more compact under the action of the supergravity field, so that the obtained magnetic powder core has high resistivity and wide frequency constant inductance characteristics. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 A cross-section metallographic graph of the magnetic powder core obtained in Example 1;

[0028] Figure 2 A cross-section metallographic graph of the magnetic powder core obtained in Comparative Example 1;

[0029] Figure 3 An effective permeability-frequency curve of the magnetic powder core obtained in Examples 1-3. DETAILED DESCRIPTION

[0030] The application provides a preparation method of a magnetic powder core, comprising the following steps:

[0031] Providing a preformed component of nanocrystalline alloy magnetic powder;

[0032] Under the action of a supergravity field, causing liquid insulation material to infiltrate into the preformed component of nanocrystalline alloy magnetic powder, and obtaining the magnetic powder core after solidification.

[0033] In the application, all the preparation raw materials are commercially available products known by those skilled in the art, unless otherwise specified.

[0034] The application provides a preformed component of nanocrystalline alloy magnetic powder.

[0035] In the application, the mesh number of the nanocrystalline alloy magnetic powder is preferably ≥100 mesh.

[0036] In the application, the nanocrystalline alloy magnetic powder preferably comprises at least one of small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder and large-particle-size nanocrystalline alloy magnetic powder. In the application, the mesh number M1 of the large-particle-size nanocrystalline alloy magnetic powder is 100 mesh≤M1≤200 mesh; the mesh number M2 of the medium-particle-size nanocrystalline alloy magnetic powder is 200 mesh

[0037] In this invention, when the nanocrystalline alloy magnetic powder is any two of small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder, and large-particle-size nanocrystalline alloy magnetic powder; the mass ratio of the small-particle-size nanocrystalline alloy magnetic powder to the medium-particle-size nanocrystalline alloy magnetic powder is preferably 1:2.3 to 9, more preferably 1:3 to 8, and even more preferably 4 to 7; the mass ratio of the small-particle-size nanocrystalline alloy magnetic powder to the large-particle-size nanocrystalline alloy magnetic powder is preferably 1:2 to 9, more preferably 1:3 to 8, and even more preferably 1:4 to 7; the mass ratio of the medium-particle-size nanocrystalline alloy magnetic powder to the large-particle-size nanocrystalline alloy magnetic powder is preferably 1:1 to 9, more preferably 1:2 to 8, and even more preferably 1:3 to 7.

[0038] In this invention, when the nanocrystalline alloy magnetic powder is small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder, or large-particle-size nanocrystalline alloy magnetic powder, the mass ratio of the small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder, and large-particle-size nanocrystalline alloy magnetic powder is preferably 1:1 to 3:1 to 8, more preferably 1:2 to 3:2 to 7, and even more preferably 1:2 to 3:3 to 6.

[0039] This invention does not impose any particular limitation on the type and source of the nanocrystalline alloy magnetic powder; any powder well-known to those skilled in the art can be used. In this invention, the microstructure of the nanocrystalline alloy magnetic powder is preferably flake-like. In a specific embodiment of this invention, the chemical composition of the nanocrystalline alloy magnetic powder is Fe. 73.5 Cu1Nb3Si 15.5 B7.

[0040] In this invention, the method for preparing the nanocrystalline alloy magnetic powder preferably includes the following steps:

[0041] The amorphous alloy strip was subjected to crystallization annealing, crushing, stress-relief annealing and sieving in sequence to obtain the nanocrystalline alloy magnetic powder.

[0042] This invention does not impose any special limitations on the type and source of the amorphous alloy ribbon; any material well known to those skilled in the art can be used. In specific embodiments of this invention, the chemical composition of the amorphous alloy ribbon is consistent with the chemical composition of the nanocrystalline alloy described in the above technical solution, and will not be repeated here.

[0043] In this invention, the crystallization annealing temperature is preferably 520–550°C, more preferably 530–540°C; the time is 2–3 hours. This invention does not impose any special limitations on the crystallization annealing process; any process well-known to those skilled in the art can be used. In a specific embodiment of this invention, the chemical composition is Fe. 73.5 Cu1Nb3Si 15.5The effective magnetic permeability of the nanocrystalline alloy ribbon obtained by crystallizing annealing of the amorphous alloy ribbon of B7 is greater than 150000.

[0044] After the crystallization annealing is completed, the nanocrystalline alloy ribbon is preferably broken in the present application. The process of breaking is not particularly limited in the present application, and can be performed by using a process well known to those skilled in the art. In the present application, the mesh number of the material obtained by breaking is preferably ≥100 mesh.

[0045] After the breaking is completed, the material obtained by breaking is preferably stress relieved annealed in the present application. In the present application, the temperature of the stress relieved annealing is preferably 400-520℃, further preferably 420-500℃, and more preferably 450-480℃; the time is preferably 1-3h, further preferably 1.2-2.8h, and more preferably 1.5-2.5h. In the present application, the stress relieved annealing is performed under vacuum; the vacuum degree is preferably 0.1-10Pa.

[0046] After the stress relieved annealing is completed, the obtained material is preferably furnace-cooled in the present application.

[0047] The process of screening is not particularly limited in the present application, and can be performed by using a process well known to those skilled in the art. In the present application, the nanocrystalline alloy magnetic powder with the mesh number described in the above technical solution can be obtained by the screening.

[0048] In a specific embodiment of the present application, the method for preparing the preformed component of the nanocrystalline alloy magnetic powder preferably comprises the following steps:

[0049] The nanocrystalline alloy magnetic powder is loaded into a mold, and is vibrated to obtain the preformed component of the nanocrystalline alloy magnetic powder.

[0050] Before the nanocrystalline alloy magnetic powder is loaded into the mold, when the nanocrystalline alloy magnetic powder is at least two of small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder and large-particle-size nanocrystalline alloy magnetic powder, the nanocrystalline alloy magnetic powder is preferably premixed in the present application. The process of premixing is not particularly limited in the present application, and can be performed by using a process well known to those skilled in the art.

[0051] In the present application, the material of the mold is preferably polypropylene, polytetrafluoroethylene or nylon. In the present application, the mold is preferably a ring mold. In the present application, the inner cavity of the ring mold is preferably 18mm, the outer cavity is preferably 28mm, and the height is preferably 80mm.

[0052] The process of vibrating is not particularly limited in the present application, and can be performed by using a process well known to those skilled in the art.

[0053] In the present application, the pore size in the preformed component of the nanocrystalline alloy magnetic powder is preferably 1-50 μm.

[0054] After obtaining the preformed component of the nanocrystalline alloy magnetic powder, the present application causes the liquid insulating material to infiltrate into the preformed component of the nanocrystalline alloy magnetic powder under the action of a supergravity field, and solidifies to obtain the magnetic powder core.

[0055] In the present application, the liquid insulating material preferably comprises epoxy resin.

[0056] In the present application, the viscosity of the liquid insulating material is preferably < 13000 mPa-s, and further preferably 10000-13000 mPa-s.

[0057] In the present application, the mass ratio of the liquid insulating material to the nanocrystalline alloy magnetic powder is preferably 1:8-12, further preferably 1:9-11, and more preferably 1:10.

[0058] In the present application, the gravity of the supergravity field is preferably 1000-3000 g, further preferably 1500-2500 g, and more preferably 1800-2000 g.

[0059] In the present application, the time of the infiltration is preferably ≥ 3 min, and further preferably 5-7 min.

[0060] In the present application, the process of the infiltration is preferably as follows: pouring the liquid insulating material onto the surface of the preformed component of the nanocrystalline alloy magnetic powder in the mold, and placing the mold in a supergravity centrifuge for infiltration.

[0061] The present application does not have special limitation on the process of the infiltration in the supergravity centrifuge, and any process known to those skilled in the art can be used.

[0062] After the completion of the infiltration, the present application further preferably comprises removing the gravity field, and then taking out the mold.

[0063] After the completion of the infiltration, the present application solidifies the product obtained after the infiltration to obtain the magnetic powder core.

[0064] In the present application, the temperature of the solidification is preferably room temperature, and the time is preferably ≥ 24 h, and further preferably 24-36 h.

[0065] After the completion of the solidification, the present application further preferably comprises sequentially demolding and cutting the material obtained after the solidification. The present application does not have special limitation on the process of the demolding and cutting, and any process known to those skilled in the art can be used.

[0066] The preparation method of the magnetic powder core has simple process, less investment equipment, convenient operation and easy batch production.

[0067] In order to further illustrate the present application, the preparation method of the magnetic powder core provided by the present application is described in detail below in combination with the drawings and examples, but they should not be understood as limiting the protection scope of the present application.

[0068] Example 1

[0069] The chemical composition of the Fe 73.5 Cu1Nb3Si 15.5 The amorphous alloy ribbons of B7 are subjected to crystallization annealing at 520 DEG C for 120 min to obtain nanocrystalline ribbons; the obtained nanocrystalline ribbons are crushed, and then subjected to stress relief annealing at a vacuum and a temperature of 500 DEG C for 1 h, and cooled in the furnace, and then screened to obtain large-particle-size nanocrystalline alloy magnetic powder (mesh number satisfies 100 mesh <= M <= 200 mesh) ;

[0070] 70 g of the obtained nanocrystalline alloy magnetic powder is taken and filled into a polypropylene ring mold with an inner cavity of 18 mm, an outer cavity of 28 mm and a height of 80 mm, and then vibrated;

[0071] 8 g of epoxy resin is poured onto the surface of the vibrated nanocrystalline alloy magnetic powder, and then the mold is placed in a supergravity centrifugal field to apply a gravity of 2000 g for infiltration for 4 min;

[0072] After the supergravity field is removed, the mold is taken out and solidified at room temperature for 36 h; then demolding treatment and cutting are performed to obtain a ring-shaped magnetic powder core with a size of 28 mm * 18 mm * 5 mm.

[0073] Example 2

[0074] The chemical composition of the Fe 73.5 Cu1Nb3Si 15.5 The amorphous alloy ribbons of B7 are subjected to crystallization annealing at 550 DEG C for 120 min to obtain nanocrystalline ribbons; the obtained nanocrystalline ribbons are crushed, and then subjected to stress relief annealing at a vacuum and a temperature of 450 DEG C for 2.5 h, and cooled in the furnace, and then screened to obtain large-particle-size nanocrystalline alloy magnetic powder (mesh number satisfies 100 mesh <= M <= 200 mesh) and medium-particle-size nanocrystalline alloy magnetic powder (mesh number satisfies 200 mesh < M <= 400 mesh) ;

[0075] 35 g of the large-particle-size nanocrystalline alloy magnetic powder and 35 g of the medium-particle-size nanocrystalline alloy magnetic powder are taken, mixed uniformly, and then filled into a polypropylene ring mold with an inner cavity of 18 mm, an outer cavity of 28 mm and a height of 80 mm, and then vibrated;

[0076] 6g epoxy resin was poured onto the surface of the vibrated nanocrystalline alloy magnetic powder, and then the mold was placed in an ultra-high gravity centrifugal field, a gravity of 1500g was applied for infiltration, and maintained for 8min;

[0077] After the ultra-high gravity field was removed, the mold was taken out and cured at room temperature for 36h; then demolding treatment and cutting were performed to obtain a ring-shaped magnetic powder core with a size of 28mm*18mm*5mm.

[0078] Example 3

[0079] The chemical composition of the nanocrystalline alloy magnetic powder was Fe 73.5 Cu1Nb3Si 15.5 The amorphous alloy ribbons of B7 were subjected to crystallization annealing at 540℃ for 120min to obtain nanocrystalline ribbons; the obtained nanocrystalline ribbons were crushed, and then subjected to stress relief annealing in vacuum at a temperature of 480℃ for 2h, and cooled in the furnace, and then sieved to obtain large-particle-size nanocrystalline alloy magnetic powder (mesh number satisfying 100mesh≤M≤200mesh), medium-particle-size nanocrystalline alloy magnetic powder (mesh number satisfying 200mesh

[0080] 42g of large-particle-size nanocrystalline alloy magnetic powder, 21g of medium-particle-size nanocrystalline alloy magnetic powder, and 7g of small-particle-size nanocrystalline alloy magnetic powder were taken, uniformly mixed, and then loaded into a polypropylene ring-shaped mold with an inner cavity of 18mm, an outer cavity of 28mm, and a height of 80mm, and vibrated;

[0081] 7g of epoxy resin was poured onto the surface of the vibrated nanocrystalline alloy magnetic powder, and then the mold was placed in an ultra-high gravity centrifugal field, a gravity of 2500g was applied for infiltration, and maintained for 5min to obtain a mixture;

[0082] After the ultra-high gravity field was removed, the mold was taken out and cured at room temperature for 36h; then demolding treatment and cutting were performed to obtain a ring-shaped magnetic powder core with a size of 28mm*18mm*5mm.

[0083] Comparative Example 1

[0084] The magnetic powder core prepared by the traditional pressing process:

[0085] The chemical composition of the nanocrystalline alloy magnetic powder was Fe 73.5 Cu1Nb3Si 15.5 The amorphous alloy ribbons of B7 were subjected to crystallization annealing at 520℃ for 120min to obtain nanocrystalline ribbons; the obtained nanocrystalline ribbons were crushed, and then subjected to stress relief annealing in vacuum at a temperature of 500℃ for 1h, and cooled in the furnace, and then sieved to obtain large-particle-size nanocrystalline alloy magnetic powder (mesh number satisfying 100mesh≤M≤200mesh);

[0086] Take 8g epoxy resin, added to the above 70g large particle size nanocrystalline alloy magnetic powder, stirring mixed evenly, placed in 80℃ drying oven drying 30min; then the dried magnetic powder into the inner cavity for 18mm, outer cavity for 28mm quenching stainless steel ring mold, under the pressure of 1000MPa, 10s, pressed into a size of 28mm*18mm*5mm ring-shaped magnetic powder core.

[0087] Performance test

[0088] Test example 1

[0089] The cross section of the magnetic powder core obtained from example 1 and comparative example 1 is tested using a zeiss microscope, and the obtained metallographic image is shown in Figure 1 and Figure 2 , wherein Figure 1 is example 1, Figure 2 is comparative example 1, from Figure 1 and Figure 2 It can be seen that the magnetic powder and liquid insulating agent prepared by using the supergravity infiltration process are more uniformly distributed.

[0090] Test example 2

[0091] The magnetic powder core obtained from examples 1-3 and comparative example 1 is tested for effective permeability in the frequency range of 1kHz-1MHz, and the test conditions are: using LCR analyzer test, the number of turns of the magnetic powder core is 10 turns, the test voltage is 2V, and the obtained effective permeability-frequency curve is shown in Figure 3 ; the effective permeability at 100kHz and the attenuation change value of the effective permeability are shown in table 1;

[0092] Table 1 effective permeability of the magnetic powder core obtained from examples 1-3 and comparative example 1

[0093] Effective permeability at 100 kHz Decay change in effective permeability Example 1 203 Less than 1% Example 2 207 Less than 1% Example 3 212 Less than 1% Comparative Example 1 35 Less than 1%

[0094] From table 1 and Figure 3 It can be seen that the magnetic powder core obtained by the present application has a constant inductance characteristic in the frequency range of 1kHz-1MHz; the permeability of the obtained magnetic powder core at 100kHz can reach more than 200, and the attenuation change value is also less than 1%; the permeability of the magnetic powder core obtained from comparative example 1 is significantly lower than that of the present application.

[0095] Test example 3

[0096] The resistivity of the magnetic powder core obtained from examples 1-3 and comparative example 1 is tested, and the test method is four-probe method; the test results are shown in table 2;

[0097] Table 2 resistivity of the magnetic powder core obtained from examples 1-3 and comparative example 1

[0098] Resistivity / Ω-cm Example 1 286 Example 2 303 Example 3 352 Comparative Example 1 28

[0099] As shown in Table 2, the magnetic powder core prepared in Examples 1-3 has a higher resistivity than that prepared in Comparative Example 1.

[0100] Test Example 4

[0101] The compression strength of the magnetic powder core prepared in Examples 1-3 and Comparative Example 1 was tested by using a universal testing machine, and the test results are shown in Table 3.

[0102] Table 3 Compression strength of the magnetic powder core prepared in Examples 1-3 and Comparative Example 1

[0103] Compressive strength / MPa Example 1 40 Example 2 35 Example 3 38 Comparative Example 1 26

[0104] As shown in Table 3, the magnetic powder core prepared in Examples 1-3 has a higher compression strength than that prepared in Comparative Example 1, which can be seen from the fact that the magnetic powder core prepared in Examples 1-3 has a higher density than that prepared in Comparative Example 1. Figure 1 and 2 The uneven distribution of the nanocrystalline alloy magnetic powder and the liquid insulating agent in Comparative Example 1 is the cause.

[0105] Although the above examples have made a detailed description of the present application, it is only a part of the embodiments of the present application, but not all the embodiments, and other embodiments can be obtained according to the present embodiments without creativity, which all belong to the protection scope of the present application.

Claims

1. A method of producing a magnetic powder core, characterized by, The steps are: The nanocrystalline alloy magnetic powder is loaded into a mold, and is vibrated to obtain a preformed component of the nanocrystalline alloy magnetic powder; Under the action of a high gravity field, a liquid insulating material is infiltrated into the preformed component of the nanocrystalline alloy magnetic powder, and is solidified to obtain the magnetic powder core; The nanocrystalline alloy magnetic powder comprises at least one of small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder and large-particle-size nanocrystalline alloy magnetic powder; The mesh number M1 of the large-particle-size nanocrystalline alloy magnetic powder is 100 mesh≤M1≤200 mesh; The mesh number M2 of the medium-particle-size nanocrystalline alloy magnetic powder is 200 mesh The mesh number M3 of the small-particle-size nanocrystalline alloy magnetic powder is M3>400 mesh; The magnetic permeability of the magnetic powder core at 100 kHz is 200 or more.

2. The production method according to claim 1, characterized by, The gravity of the high gravity field is 1000-3000 g.

3. The preparation method according to claim 1, characterized in that, When the nanocrystalline alloy magnetic powder is any two of small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder and large-particle-size nanocrystalline alloy magnetic powder; The mass ratio of the small-particle-size nanocrystalline alloy magnetic powder and the medium-particle-size nanocrystalline alloy magnetic powder is 1:2.3-9; The mass ratio of the small-particle-size nanocrystalline alloy magnetic powder and the large-particle-size nanocrystalline alloy magnetic powder is 1:2-9; The mass ratio of the medium-particle-size nanocrystalline alloy magnetic powder and the large-particle-size nanocrystalline alloy magnetic powder is 1:1-9.

4. The method of claim 1, wherein, When the nanocrystalline alloy magnetic powder is small-particle-size nanocrystalline alloy magnetic powder, medium-particle-size nanocrystalline alloy magnetic powder and large-particle-size nanocrystalline alloy magnetic powder, the mass ratio of the small-particle-size nanocrystalline alloy magnetic powder, the medium-particle-size nanocrystalline alloy magnetic powder and the large-particle-size nanocrystalline alloy magnetic powder is 1:1-3:1-8.

5. The method of claim 1, wherein the step of forming the first and second layers is performed by a method selected from the group consisting of: sputtering, evaporation, and chemical vapor deposition. The viscosity of the liquid insulating material is <13000 mPa·s.

6. The production method according to claim 5, wherein The mass ratio of the liquid insulating material and the nanocrystalline alloy magnetic powder is 1:8-12.

7. The preparation method according to claim 1, characterized in that, The pore size in the preformed component of the nanocrystalline alloy magnetic powder is 1-50 μm; The infiltration time is ≥3 min.

8. The method of claim 1, wherein, The solidification temperature is room temperature, and the time is ≥24 h.

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