Soft magnetic composite material and preparation method thereof

Abstract

The invention discloses a soft magnetic composite material and a preparation method thereof, and belongs to the technical field of soft magnetic materials. The preparation method of the soft magnetic composite material comprises the steps that iron, nickel, manganese, aluminum, silicon and chromium are prepared into superfine alloy powder with the D50 particle size ranging from 100 nm to 3000 nm, then the superfine alloy powder reacts with 3-aminopropyltriethoxysilane and tetraethoxysilane firstly and then reacts with cyclobutane tetracarboxylic dianhydride and 3-aminobenzophenone, and the soft magnetic composite material is prepared. The invention discloses a soft magnetic composite material with excellent direct current bias performance and excellent quality factor and a preparation method thereof.

Description

Technical Field

[0001] The present invention relates to the technical field of soft magnetic materials, and in particular to a soft magnetic composite material and a preparation method thereof. Background Art

[0002] Soft magnetic composites are formed by mixing and pressing a metal magnetic powder matrix and an insulating coating. Their magnetic properties are primarily determined by the properties of the magnetic powder itself, while their insulation and mechanical properties are primarily determined by the insulating coating. Soft magnetic composites are isotropic in magnetic, mechanical, and thermal properties, resulting in excellent soft magnetic properties and frequency characteristics. The composite coating structure also greatly facilitates the design and application of soft magnetic composites.

[0003] Insulation coating refers to the use of physical or chemical methods to prepare an insulating coating on the surface of magnetic powder. The insulating layer can effectively isolate the current conduction between magnetic powders, increase the resistivity of the soft magnetic composite material, and thus reduce eddy current losses. The insulation coating process can be summarized as a process of transitioning from single-layer organic coating to inorganic-organic composite coating and double-layer inorganic coating. Initially, to ensure the mechanical strength of the soft magnetic composite material, organic coating materials such as epoxy resin, silicone resin, phenolic resin and other thermosetting resins were mainly used as coating agents. Thermosetting resins inherently have excellent insulating properties, and the process is simple and easy to operate, making them widely used in industrial production. However, organic coating materials have poor thermal stability, and excessively high temperatures can accelerate resin aging and even decompose. Inorganic coating materials have excellent thermal stability, but the wettability between the inorganic coating agent and the metal matrix is poor. Therefore, there is a need for a new soft magnetic composite material and its preparation method to prepare a soft magnetic composite material with excellent comprehensive performance. Summary of the Invention

[0004] The purpose of the present invention is to provide a soft magnetic composite material and a preparation method thereof, so as to improve the DC bias performance and quality factor of the soft magnetic composite material.

[0005] The technical solutions adopted by the present invention to achieve the above-mentioned purpose are: A method for preparing a soft magnetic composite material, comprising: S1. Iron, nickel, manganese, aluminum, silicon, and chromium are smelted into an alloy at high temperature, and the alloy is heated to boiling point by evaporation-condensation method, and then steam-cooled to obtain ultrafine alloy powder with a D50 particle size of 100-3000 nm; S2, reacting the ultrafine alloy powder with 3-aminopropyltriethoxysilane and ethyl orthosilicate, and then reacting with a surface modifier to obtain a soft magnetic composite material; The surface modifier comprises cyclobutanetetracarboxylic acid dianhydride and 3-aminobenzophenone, the mass ratio of the ultrafine alloy powder to the cyclobutanetetracarboxylic acid dianhydride is 1:2-4, and the mass ratio of the ultrafine alloy powder to the 3-aminobenzophenone is 1:2-4.

[0006] The invention prepares ultrafine alloy powder from iron, nickel, manganese, aluminum, silicon and chromium, reacts the ultrafine alloy powder with 3-aminopropyltriethoxysilane and ethyl orthosilicate, coats the surface of the ultrafine alloy powder with a silicon dioxide coating layer, and then uses cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silicon dioxide coating layer, thereby preparing a soft magnetic composite material with excellent direct current bias performance and excellent quality factor.

[0007] Preferably, the mass ratio of iron to nickel is 1:1-2.

[0008] Preferably, the mass ratio of iron to manganese is 1:0.001-0.02.

[0009] Preferably, the mass ratio of iron to aluminum is 1:0.001-0.02.

[0010] Preferably, the mass ratio of iron to silicon is 1:0.001-0.02.

[0011] Preferably, the mass ratio of iron to chromium is 0.001-0.02.

[0012] Preferably, the usage ratio of the ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1 g: 2-4 mL.

[0013] Preferably, the usage ratio of the ultrafine alloy powder to ethyl orthosilicate is 1 g: 1-2 mL.

[0014] Preferably, the preparation of the soft magnetic composite material is specifically as follows: S1. Iron, nickel, manganese, aluminum, silicon, and chromium are smelted into an alloy at high temperature, and the alloy is heated to boiling point by evaporation-condensation method, and then steam-cooled to obtain ultrafine alloy powder with a D50 particle size of 100-3000 nm; S2. Add anhydrous ethanol to the ultrafine alloy powder at 50-60°C, stir at a speed of 400-600 r / min, add 3-aminopropyltriethoxysilane and deionized water, add ethyl orthosilicate, react at 40-60°C for 2-5 hours, wash with anhydrous ethanol 2-5 times, filter and dry to obtain a soft magnetic composite material.

[0015] More preferably, the mass ratio of iron to nickel is 1:1-2.

[0016] More preferably, the mass ratio of iron to manganese is 1:0.001-0.02.

[0017] More preferably, the mass ratio of iron to aluminum is 1:0.001-0.02.

[0018] More preferably, the mass ratio of iron to silicon is 1:0.001-0.02.

[0019] More preferably, the mass ratio of iron to chromium is 0.001-0.02.

[0020] More preferably, the usage ratio of the ultrafine alloy powder to anhydrous ethanol is 1 g: 5-10 mL.

[0021] More preferably, the usage ratio of the ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1 g: 2-4 mL.

[0022] More preferably, the volume ratio of anhydrous ethanol to deionized water is 1:1-6.

[0023] More preferably, the usage ratio of the ultrafine alloy powder to tetraethyl orthosilicate is 1 g: 1-2 mL.

[0024] Preferably, in the preparation of the soft magnetic composite material, a surface modifier is further added in step S2 for reaction, and the surface modifier includes cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone. Step S2 is specifically as follows: At 50-60°C, anhydrous ethanol is added to the ultrafine alloy powder, and the mixture is stirred at a speed of 400-600 r / min. 3-aminopropyltriethoxysilane and deionized water are then added, followed by ethyl orthosilicate. The mixture is reacted at 40-60°C for 2-5 hours, and nitrogen is introduced for 30-60 minutes. Cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone are then added, and the mixture is stirred for 24-36 hours. The mixture is then washed with anhydrous ethanol 2-5 times, filtered, and dried to obtain a soft magnetic composite material. Using cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica coating may improve the integrity and uniformity of the surface insulating layer of the soft magnetic composite material by reducing the surface chemical activity of the silica coating and reducing interparticle agglomeration, thereby improving the DC bias performance and quality factor of the soft magnetic composite material.

[0025] More preferably, the usage ratio of the ultrafine alloy powder to anhydrous ethanol is 1 g: 5-10 mL.

[0026] More preferably, the usage ratio of the ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1 g: 2-4 mL.

[0027] More preferably, the volume ratio of anhydrous ethanol to deionized water is 1:1-6.

[0028] More preferably, the usage ratio of the ultrafine alloy powder to tetraethyl orthosilicate is 1 g: 1-2 mL.

[0029] More preferably, the mass ratio of the ultrafine alloy powder to the cyclobutanetetracarboxylic dianhydride is 1:2-4.

[0030] More preferably, the mass ratio of the ultrafine alloy powder to 3-aminobenzophenone is 1:2-4.

[0031] Preferably, in the preparation of the soft magnetic composite material, the silicon dioxide coating layer is further modified using N-(3-trimethoxysilylpropyl)ethylenediamine in step S2. Specifically, step S2 is: At 50-60° C., anhydrous ethanol is added to the ultrafine alloy powder, and the mixture is stirred at a speed of 400-600 r / min. 3-aminopropyltriethoxysilane and deionized water are added, and then ethyl orthosilicate is added. The mixture is reacted at 40-60° C. for 2-5 hours, and nitrogen is introduced for 30-60 minutes. Cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone are added, and the mixture is stirred and reacted for 24-36 hours. The mixture is washed with anhydrous ethanol for 2-5 times, filtered, and nitrogen is introduced for 30-60 minutes. The ethanol solution is added and stirred to disperse the mixture. N-(3-trimethoxysilylpropyl)ethylenediamine is added, and the mixture is stirred and reacted at 30-50° C. for 36-60 hours. The mixture is washed with anhydrous ethanol for 2-5 times, filtered, and dried to obtain a soft magnetic composite material. The use of N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica wrapping layer is beneficial to the formation of the silica wrapping layer, further improving the thermal stability and mechanical properties of the insulating layer of the soft magnetic composite material, thereby further improving the DC bias performance and quality factor of the soft magnetic composite material.

[0032] More preferably, the usage ratio of the ultrafine alloy powder to anhydrous ethanol is 1 g: 5-10 mL.

[0033] More preferably, the usage ratio of the ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1 g: 2-4 mL.

[0034] More preferably, the volume ratio of anhydrous ethanol to deionized water is 1:1-6.

[0035] More preferably, the usage ratio of the ultrafine alloy powder to tetraethyl orthosilicate is 1 g: 1-2 mL.

[0036] More preferably, the mass ratio of the ultrafine alloy powder to the cyclobutanetetracarboxylic dianhydride is 1:2-4.

[0037] More preferably, the mass ratio of the ultrafine alloy powder to 3-aminobenzophenone is 1:2-4.

[0038] More preferably, the mass concentration of the ethanol solution is 50-100%, and the usage ratio of the ultrafine alloy powder to the ethanol solution is 1 g: 5-10 mL.

[0039] More preferably, the mass ratio of the ultrafine alloy powder to N-(3-trimethoxysilylpropyl)ethylenediamine is 1:1-2.

[0040] The invention also discloses the soft magnetic composite material prepared by the method.

[0041] The invention also discloses the application of the soft magnetic composite material in preparing high-performance inductors.

[0042] The present invention prepares an ultrafine alloy powder having a D50 particle size of 100-3000 nm from iron, nickel, manganese, aluminum, silicon, and chromium, reacts the ultrafine alloy powder with 3-aminopropyltriethoxysilane and ethyl orthosilicate, coats the surface of the ultrafine alloy powder with a silica coating, modifies the silica coating with cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone, and further modifies the silica coating with N-(3-trimethoxysilylpropyl)ethylenediamine. The soft magnetic composite material prepared by the present invention has the following beneficial effects: the DC bias performance is excellent, with a DC bias performance of 66.7-82.8%; the quality factor is excellent, with a quality factor of 63.4-96.1. Therefore, the present invention provides a soft magnetic composite material with excellent DC bias performance and quality factor and a preparation method thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is the SEM image of the soft magnetic composite material prepared in Example 1. DETAILED DESCRIPTION

[0044] The present invention will be further described in detail below in conjunction with specific embodiments. The examples provided are only for illustrating the present invention and are not intended to limit the scope of the present invention. The examples provided below can serve as a guide for further improvements by those skilled in the art and are not intended to limit the present invention in any way.

[0045] The experimental methods in the following examples are conventional methods unless otherwise specified. The materials and reagents used in the following examples are commercially available unless otherwise specified.

[0046] Example 1: Preparation of soft magnetic composite materials, including, S1. Iron, nickel, manganese, aluminum, silicon, and chromium are smelted into an alloy at high temperature. The metals are heated to boiling point using an evaporation-condensation method, followed by steam cooling to obtain an ultrafine alloy powder with a D50 particle size of 750 nm. The mass ratio of iron to nickel is 1:1, the mass ratio of iron to manganese is 1:0.01, the mass ratio of iron to aluminum is 1:0.01, the mass ratio of iron to silicon is 1:0.01, and the mass ratio of iron to chromium is 0.01. S2. At 55°C, add anhydrous ethanol to the ultrafine alloy powder prepared in step S1, stir at 500 r / min, add 3-aminopropyltriethoxysilane and deionized water, add ethyl orthosilicate, and react at 50°C for 3 hours. Wash three times with anhydrous ethanol, filter, and dry to obtain a soft magnetic composite material. The ratio of ultrafine alloy powder to anhydrous ethanol is 1g:8.5mL; the ratio of ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1g:4mL; the volume ratio of anhydrous ethanol to deionized water is 1:3; and the ratio of ultrafine alloy powder to ethyl orthosilicate is 1g:1.2mL.

[0047] Example 2: Preparation of soft magnetic composite materials, including, S1. Iron, nickel, manganese, aluminum, silicon, and chromium are smelted into an alloy at high temperature. The metals are heated to boiling point using an evaporation-condensation method, followed by steam cooling to obtain an ultrafine alloy powder with a D50 particle size of 750 nm. The mass ratio of iron to nickel is 1:1, the mass ratio of iron to manganese is 1:0.01, the mass ratio of iron to aluminum is 1:0.01, the mass ratio of iron to silicon is 1:0.01, and the mass ratio of iron to chromium is 0.01. S2. At 55°C, add anhydrous ethanol to the ultrafine alloy powder prepared in step S1, stir at a speed of 500 r / min, add 3-aminopropyltriethoxysilane and deionized water, add ethyl orthosilicate, react at 50°C for 3 hours, introduce nitrogen for 30 minutes, add cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone, stir and react for 24 hours, wash with anhydrous ethanol three times, filter, and dry to obtain a soft magnetic composite material. The amount ratio of ultrafine alloy powder to anhydrous ethanol is 1g:8.5mL; the amount ratio of ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1g:4mL; the volume ratio of anhydrous ethanol to deionized water is 1:3; the amount ratio of ultrafine alloy powder to ethyl orthosilicate is 1g:1.2mL; the mass ratio of ultrafine alloy powder to cyclobutanetetracarboxylic dianhydride is 1:4; and the mass ratio of ultrafine alloy powder to 3-aminobenzophenone is 1:4.

[0048] Example 3: The only difference between this embodiment and embodiment 2 is the preparation of the soft magnetic composite material.

[0049] The preparation of the soft magnetic composite material was carried out under the same conditions as in Example 2 except that the mass ratio of the ultrafine alloy powder to cyclobutanetetracarboxylic dianhydride was changed to 1:2.

[0050] Example 4: The only difference between this embodiment and embodiment 2 is the preparation of the soft magnetic composite material.

[0051] The preparation of the soft magnetic composite material was carried out under the same conditions as in Example 2 except that the mass ratio of the ultrafine alloy powder to 3-aminobenzophenone was changed to 1:2.

[0052] Example 5: The only difference between this embodiment and embodiment 2 is the preparation of the soft magnetic composite material.

[0053] Preparation of soft magnetic composite materials, including, S1. Iron, nickel, manganese, aluminum, silicon, and chromium are smelted into an alloy at high temperature. The metals are heated to boiling point using an evaporation-condensation method, followed by steam cooling to obtain an ultrafine alloy powder with a D50 particle size of 750 nm. The mass ratio of iron to nickel is 1:1, the mass ratio of iron to manganese is 1:0.01, the mass ratio of iron to aluminum is 1:0.01, the mass ratio of iron to silicon is 1:0.01, and the mass ratio of iron to chromium is 0.01. S2. At 55°C, add anhydrous ethanol to the ultrafine alloy powder prepared in step S1, stir at a speed of 500 r / min, add 3-aminopropyltriethoxysilane and deionized water, add ethyl orthosilicate, react at 50°C for 3 hours, introduce nitrogen for 30 minutes, add cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone, stir and react for 24 hours, wash with anhydrous ethanol three times, filter, introduce nitrogen for 30 minutes, add ethanol solution and stir to disperse, add N-(3-trimethoxysilylpropyl)ethylenediamine, stir and react at 40°C for 48 hours, wash with anhydrous ethanol three times, filter, and dry to obtain a soft magnetic composite material. The amount ratio of ultrafine alloy powder to anhydrous ethanol is 1g:8.5mL; the amount ratio of ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1g:4mL; the volume ratio of anhydrous ethanol to deionized water is 1:3; the amount ratio of ultrafine alloy powder to ethyl orthosilicate is 1g:1.2mL; the mass ratio of ultrafine alloy powder to cyclobutanetetracarboxylic dianhydride is 1:4; the mass ratio of ultrafine alloy powder to 3-aminobenzophenone is 1:4; the mass concentration of the ethanol solution is 75%, the amount ratio of ultrafine alloy powder to ethanol solution is 1g:8mL; the mass ratio of ultrafine alloy powder to N-(3-trimethoxysilylpropyl)ethylenediamine is 1:2.

[0054] Example 6: The only difference between this embodiment and embodiment 5 is the preparation of the soft magnetic composite material.

[0055] The preparation of the soft magnetic composite material was carried out under the same conditions as in Example 5 except that the mass ratio of the ultrafine alloy powder to N-(3-trimethoxysilylpropyl)ethylenediamine was changed to 1:1.

[0056] Comparative Example 1: The only difference between this comparative example and Example 2 is the preparation of the soft magnetic composite material.

[0057] The soft magnetic composite material was prepared under the same conditions as in Example 2 except that 3-aminobenzophenone was not added.

[0058] Comparative Example 2: The only difference between this comparative example and Example 2 is the preparation of the soft magnetic composite material.

[0059] The preparation of the soft magnetic composite material was carried out under the same conditions as in Example 2 except that cyclobutanetetracarboxylic dianhydride was not added.

[0060] Comparative Example 3: The only difference between this comparative example and Example 5 is the preparation of the soft magnetic composite material.

[0061] The soft magnetic composite material was prepared under the same conditions as in Example 5 except that cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone were not added.

[0062] Experimental example: 1. Material characterization The surface morphology of the soft magnetic composite material prepared in Example 1 was observed using a scanning electron microscope.

[0063] Figure 1 This is an SEM image of the soft magnetic composite material prepared in Example 1, with a scale of 100 nm. The soft magnetic composite material prepared in Example 1 is in the form of round particles, with an insulating protective layer coated on the surface.

[0064] 2. DC bias performance The DC bias performance of the soft magnetic composite materials prepared in Examples 1-6 of the present invention and Comparative Examples 1-3 under a bias field of 100 Oe was measured using an LCR precision impedance analyzer configured with an applied current of 0-10 A.

[0065] Table 1 DC bias performance (%)

[0066] As can be seen from Table 1, the DC bias performance of the soft magnetic composite materials prepared in Examples 2-4 of the present invention is better than that of Example 1. This is because in the preparation of the soft magnetic composite material, Examples 2-4 first wrap a silica coating on the surface of the ultrafine alloy powder, and then use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica coating; the DC bias performance of the soft magnetic composite material prepared in Example 2 of the present invention is better than that of Examples 3-4. This is because in the preparation of the soft magnetic composite material, the amounts of cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone used are different. This shows that the DC bias performance of the soft magnetic composite material can be improved by modifying the silica coating using cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone. The soft magnetic composite materials prepared in Examples 2-4 of the present invention exhibit superior DC bias performance compared to Comparative Examples 1-2. This is because, in the preparation of the soft magnetic composite materials, Examples 2-4 utilize cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone in combination to modify the silica coating, whereas Comparative Example 1 utilizes only cyclobutanetetracarboxylic dianhydride to modify the silica coating, and Comparative Example 2 utilizes only 3-aminobenzophenone to modify the silica coating. This demonstrates that, compared to modifying the silica coating using either cyclobutanetetracarboxylic dianhydride or 3-aminobenzophenone alone, the combined use of cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica coating improves the DC bias performance of the soft magnetic composite materials.

[0067] The DC bias performance of the soft magnetic composite material prepared in Examples 5-6 of the present invention is better than that of Example 2, because in the preparation of the soft magnetic composite material, Examples 5-6 further use N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica coating; the DC bias performance of the soft magnetic composite material prepared in Example 5 is better than that of Example 6, because in the preparation of the soft magnetic composite material, the amount of N-(3-trimethoxysilylpropyl)ethylenediamine used is different; the DC bias performance of the soft magnetic composite material prepared in Examples 5-6 is better than that of Comparative Example 3, because in the preparation of the soft magnetic composite material, Comparative Example 3 only uses N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica coating, and does not use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica coating. This shows that further using N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica coating can further improve the DC bias performance of the soft magnetic composite material.

[0068] 3. Quality factor The quality factors of the soft magnetic composite materials prepared in Examples 1-6 of the present invention and Comparative Examples 1-3 were measured using an LCR precision impedance analyzer. The quality factor test frequency was 1 MHz and the voltage was 250 mVac.

[0069] Table 2 Quality factors

[0070] As can be seen from Table 2, the quality factor of the soft magnetic composite material prepared in Examples 2-4 of the present invention is better than that of Example 1. This is because in the preparation of the soft magnetic composite material, Examples 2-4 first wrap a silica coating on the surface of the ultrafine alloy powder, and then use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica coating; the quality factor of the soft magnetic composite material prepared in Example 2 of the present invention is better than that of Examples 3-4. This is because in the preparation of the soft magnetic composite material, the amounts of cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone used are different. This shows that the quality factor of the soft magnetic composite material can be improved by modifying the silica coating using cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone. The quality factor of the soft magnetic composite materials prepared in Examples 2-4 of the present invention is better than that of Comparative Examples 1-2. This is because, in the preparation of the soft magnetic composite materials, Examples 2-4 use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone in combination to modify the silica coating, while Comparative Example 1 uses only cyclobutanetetracarboxylic dianhydride to modify the silica coating, and Comparative Example 2 uses only 3-aminobenzophenone to modify the silica coating. This shows that compared with using cyclobutanetetracarboxylic dianhydride or 3-aminobenzophenone alone to modify the silica coating, the collaborative use of cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica coating can improve the quality factor of the soft magnetic composite material.

[0071] The quality factor of the soft magnetic composite material prepared in Examples 5-6 of the present invention is better than that of Example 2, because in the preparation of the soft magnetic composite material, Examples 5-6 further use N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica coating; the quality factor of the soft magnetic composite material prepared in Example 5 is better than that of Example 6, because in the preparation of the soft magnetic composite material, the amount of N-(3-trimethoxysilylpropyl)ethylenediamine used is different; the quality factor of the soft magnetic composite material prepared in Examples 5-6 is better than that of Comparative Example 3, because in the preparation of the soft magnetic composite material, Comparative Example 3 only uses N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica coating, and does not use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica coating. This shows that further using N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica coating can further improve the quality factor of the soft magnetic composite material.

[0072] The conventional operations in the operating steps of the present invention are well known to those skilled in the art and will not be described in detail here.

[0073] The embodiments described above provide a detailed description of the technical solutions of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements or similar substitutions made within the scope of the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A soft magnetic composite material and a preparation method thereof, comprising: S1. Iron, nickel, manganese, aluminum, silicon, and chromium are smelted into an alloy at high temperature, and the alloy is heated to boiling point by evaporation-condensation method, and then steam-cooled to obtain ultrafine alloy powder with a D50 particle size of 100-3000 nm; S2, reacting the ultrafine alloy powder with 3-aminopropyltriethoxysilane and ethyl orthosilicate, and then reacting with a surface modifier to obtain a soft magnetic composite material; The surface modifier includes cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone. The mass ratio of the ultrafine alloy powder to cyclobutanetetracarboxylic dianhydride is 1:2-4, and the mass ratio of the ultrafine alloy powder to 3-aminobenzophenone is 1:2-4.

2. A soft magnetic composite material and a preparation method thereof according to claim 1, characterized in that: The mass ratio of iron to nickel is 1:1-2.

3. A soft magnetic composite material and a preparation method thereof according to claim 1, characterized in that: The mass ratio of iron to manganese is 1:0.001-0.

02.

4. A soft magnetic composite material and a preparation method thereof according to claim 1, characterized in that: The mass ratio of iron to aluminum is 1:0.001-0.

02.

5. A soft magnetic composite material and a preparation method thereof according to claim 1, characterized in that: The mass ratio of iron to silicon is 1:0.001-0.

02.

6. A soft magnetic composite material and a preparation method thereof according to claim 1, characterized in that: The mass ratio of iron to chromium is 0.001-0.

02.

7. A soft magnetic composite material and a preparation method thereof according to claim 1, characterized in that: The usage ratio of the ultrafine alloy powder and 3-aminopropyltriethoxysilane is 1g:2-4mL.

8. A soft magnetic composite material and a preparation method thereof according to claim 1, characterized in that: The usage ratio of the ultrafine alloy powder and ethyl orthosilicate is 1g:1-2mL.

9. The soft magnetic composite material prepared by the method according to any one of claims 1 to 8.

10. Use of the soft magnetic composite material according to claim 9 in preparing high-performance inductors.

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