A soft magnetic composite material and preparation method thereof

Abstract

A soft magnetic composite material and a preparation method thereof, belonging to the technical field of soft magnetic materials. The preparation method of the soft magnetic composite material comprises preparing an ultrafine alloy powder with a D50 particle size of 100-3000nm from iron, nickel, manganese, aluminum, silicon and chromium, and then reacting the ultrafine alloy powder with 3-aminopropyltriethoxysilane and ethyl orthosilicate, and then reacting with cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to prepare the soft magnetic composite material. The invention discloses a soft magnetic composite material with excellent DC bias performance and excellent quality factor and a preparation method thereof.

Description

Technical Field

[0001] The 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 composite materials are made of metal magnetic powder matrix and insulating coating layer through mixing and pressing. The magnetic properties of soft magnetic composite materials mainly depend on the properties of magnetic powder itself, while the insulation and mechanical properties mainly depend on the insulating coating layer. Soft magnetic composite materials are isotropic in magnetic properties, mechanical properties and thermal properties, so they have good soft magnetic properties and frequency characteristics. At the same time, the composite coating structure also brings great convenience to the application design of soft magnetic composite materials.

[0003] Insulation coating refers to the use of physical or chemical methods to prepare an insulating coating layer on the surface of magnetic powder. The insulating layer can effectively isolate the current conduction between magnetic powders, improve the resistivity of soft magnetic composite materials, and thus reduce eddy current losses. The insulation coating process can be attributed to the process of transformation from single-layer organic coating to inorganic-organic composite coating and double-layer inorganic coating. At the beginning, in order to ensure the mechanical strength of soft magnetic composite materials, organic coating materials such as epoxy resin, silicone resin, phenolic resin and other thermosetting resins were mainly used as coating agents. Thermosetting resins themselves have excellent insulation properties, and the process is simple and easy to operate, so they are widely used in industrial production. However, organic coating materials have poor thermal stability, and excessively high temperatures will accelerate the aging of the resin and even decompose it. Inorganic coating materials have excellent thermal stability, but the wettability between inorganic coating agents and metal substrates is poor. Therefore, a new soft magnetic composite material and its preparation method are needed 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 solution adopted by the present invention to achieve the above-mentioned purpose is:

[0006] A method for preparing a soft magnetic composite material, comprising:

[0007] 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 100-3000nm;

[0008] 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;

[0009] 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.

[0010] 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, so as to prepare a soft magnetic composite material with excellent direct current bias performance and excellent quality factor.

[0011] Preferably, the mass ratio of iron to nickel is 1:1-2.

[0012] Preferably, the mass ratio of iron to manganese is 1:0.001-0.02.

[0013] Preferably, the mass ratio of iron to aluminum is 1:0.001-0.02.

[0014] Preferably, the mass ratio of iron to silicon is 1:0.001-0.02.

[0015] Preferably, the mass ratio of iron to chromium is 0.001-0.02.

[0016] Preferably, the usage ratio of the ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1 g: 2-4 mL.

[0017] Preferably, the usage ratio of the ultrafine alloy powder to tetraethyl orthosilicate is 1 g: 1-2 mL.

[0018] Preferably, the preparation of the soft magnetic composite material comprises:

[0019] 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 100-3000nm;

[0020] S2. At 50-60°C, add anhydrous ethanol to the ultrafine alloy powder, stir at a speed of 400-600r / min, add 3-aminopropyltriethoxysilane and deionized water, add ethyl orthosilicate, react at 40-60°C for 2-5h, wash with anhydrous ethanol 2-5 times, filter and dry to obtain a soft magnetic composite material.

[0021] More preferably, the mass ratio of iron to nickel is 1:1-2.

[0022] More preferably, the mass ratio of iron to manganese is 1:0.001-0.02.

[0023] More preferably, the mass ratio of iron to aluminum is 1:0.001-0.02.

[0024] More preferably, the mass ratio of iron to silicon is 1:0.001-0.02.

[0025] More preferably, the mass ratio of iron to chromium is 0.001-0.02.

[0026] More preferably, the usage ratio of the ultrafine alloy powder to anhydrous ethanol is 1 g: 5-10 mL.

[0027] More preferably, the usage ratio of the ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1 g: 2-4 mL.

[0028] More preferably, the volume ratio of anhydrous ethanol to deionized water is 1:1-6.

[0029] More preferably, the usage ratio of the ultrafine alloy powder to tetraethyl orthosilicate is 1 g: 1-2 mL.

[0030] 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:

[0031] Under the condition of 50-60°C, anhydrous ethanol is added to the ultrafine alloy powder, stirred at a speed of 400-600r / min, 3-aminopropyl triethoxysilane and deionized water are added, and ethyl orthosilicate is added, and the reaction is carried out at the condition of 40-60°C for 2-5h, nitrogen is introduced for 30-60min, cyclobutane tetracarboxylic dianhydride and 3-aminobenzophenone are added, and the reaction is stirred for 24-36h, and the powder is washed with anhydrous ethanol for 2-5 times, filtered and dried to obtain a soft magnetic composite material. The modification of the silica coating layer by using cyclobutane tetracarboxylic dianhydride and 3-aminobenzophenone 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 layer and reducing the agglomeration between particles, thereby 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 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] 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, and step S2 is specifically as follows:

[0039] 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 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, and filtered. Nitrogen is introduced for 30-60 minutes. An ethanol solution is added and stirred and dispersed. 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, and filtered and dried to obtain a soft magnetic composite material. The use of N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica encapsulation layer is beneficial to the formation of the silica encapsulation 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.

[0040] More preferably, the usage ratio of the ultrafine alloy powder to anhydrous ethanol is 1 g: 5-10 mL.

[0041] More preferably, the usage ratio of the ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1 g: 2-4 mL.

[0042] More preferably, the volume ratio of anhydrous ethanol to deionized water is 1:1-6.

[0043] More preferably, the usage ratio of the ultrafine alloy powder to tetraethyl orthosilicate is 1 g: 1-2 mL.

[0044] More preferably, the mass ratio of the ultrafine alloy powder to cyclobutanetetracarboxylic dianhydride is 1:2-4.

[0045] More preferably, the mass ratio of the ultrafine alloy powder to 3-aminobenzophenone is 1:2-4.

[0046] 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.

[0047] More preferably, the mass ratio of the ultrafine alloy powder to N-(3-trimethoxysilylpropyl)ethylenediamine is 1:1-2.

[0048] The invention also discloses the soft magnetic composite material prepared by the method.

[0049] The invention also discloses the application of the soft magnetic composite material in preparing high-performance inductors.

[0050] The present invention prepares ultrafine alloy powder with a D50 particle size of 100-3000nm by using iron, nickel, manganese, aluminum, silicon and chromium, and then reacts the ultrafine alloy powder with 3-aminopropyltriethoxysilane and ethyl orthosilicate, wraps a silicon dioxide coating layer on the surface of the ultrafine alloy powder, and uses cyclobutanetetracarboxylic acid dianhydride and 3-aminobenzophenone to modify the silicon dioxide coating layer, and then further uses N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silicon dioxide coating layer, so that it has the following beneficial effects: the soft magnetic composite material prepared by the present invention has better DC bias performance, the DC bias performance is 66.7-82.8%; the quality factor is better, the quality factor is 63.4-96.1. Therefore, the present invention is a soft magnetic composite material with excellent DC bias performance and excellent quality factor and a preparation method thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is the SEM image of the soft magnetic composite material prepared in Example 1. DETAILED DESCRIPTION

[0052] The present invention is further described in detail below in conjunction with specific embodiments, and the examples provided are only for illustrating the present invention, rather than for limiting the scope of the present invention. The examples provided below can be used as a guide for further improvements by those of ordinary skill in the art, and do not constitute a limitation of the present invention in any way.

[0053] The experimental methods in the following examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples are commercially available unless otherwise specified.

[0054] Embodiment 1:

[0055] Preparation of soft magnetic composite materials, including,

[0056] S1. Iron, nickel, manganese, aluminum, silicon and chromium are smelted into alloy at high temperature, and the metal is heated to boiling point by evaporation condensation method, and then steam cooled to obtain ultrafine alloy powder with a D50 particle size of 750nm. 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;

[0057] 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 tetraethyl orthosilicate, react at 50°C for 3 hours, wash with anhydrous ethanol 3 times, filter and dry to obtain a soft magnetic composite material. The dosage ratio of ultrafine alloy powder to anhydrous ethanol is 1g:8.5mL; the dosage ratio of ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1g:4mL; the volume ratio of anhydrous ethanol to deionized water is 1:3; the dosage ratio of ultrafine alloy powder to tetraethyl orthosilicate is 1g:1.2mL.

[0058] Embodiment 2:

[0059] Preparation of soft magnetic composite materials, including,

[0060] S1. Iron, nickel, manganese, aluminum, silicon and chromium are smelted into alloy at high temperature, and the metal is heated to boiling point by evaporation condensation method, and then steam cooled to obtain ultrafine alloy powder with a D50 particle size of 750nm. 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;

[0061] S2. At 55°C, add anhydrous ethanol to the ultrafine alloy powder prepared in step S1, stir at a speed of 500r / min, add 3-aminopropyltriethoxysilane and deionized water, add tetraethyl orthosilicate, react at 50°C for 3h, introduce nitrogen for 30min, add cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone, stir and react for 24h, wash with anhydrous ethanol for 3 times, filter and dry to obtain a soft magnetic composite material. The dosage ratio of ultrafine alloy powder to anhydrous ethanol is 1g:8.5mL; the dosage ratio of ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1g:4mL; the volume ratio of anhydrous ethanol to deionized water is 1:3; the dosage ratio of ultrafine alloy powder to tetraethyl 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.

[0062] Embodiment 3:

[0063] The difference between this embodiment and embodiment 2 is only the preparation of the soft magnetic composite material.

[0064] The preparation of the soft magnetic composite material is carried out under the same conditions as in Example 2 except that the mass ratio of the ultrafine alloy powder to cyclobutanetetracarboxylic dianhydride is changed to 1:2.

[0065] Embodiment 4:

[0066] The difference between this embodiment and embodiment 2 is only the preparation of the soft magnetic composite material.

[0067] 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.

[0068] Embodiment 5:

[0069] The difference between this embodiment and embodiment 2 is only the preparation of the soft magnetic composite material.

[0070] Preparation of soft magnetic composite materials, including,

[0071] S1. Iron, nickel, manganese, aluminum, silicon and chromium are smelted into alloy at high temperature, and the metal is heated to boiling point by evaporation condensation method, and then steam cooled to obtain ultrafine alloy powder with a D50 particle size of 750nm. 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;

[0072] 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 tetraethyl orthosilicate, react at 50°C for 3 hours, pass nitrogen for 30 minutes, add cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone, stir and react for 24 hours, wash with anhydrous ethanol for 3 times, filter, pass nitrogen for 30 minutes, add ethanol solution, stir and disperse, add N-(3-trimethoxysilylpropyl)ethylenediamine, stir and react at 40°C for 48 hours, wash with anhydrous ethanol for 3 times, filter and dry, and obtain a soft magnetic composite material. The dosage ratio of ultrafine alloy powder to anhydrous ethanol is 1g:8.5mL; the dosage ratio of ultrafine alloy powder to 3-aminopropyltriethoxysilane is 1g:4mL; the volume ratio of anhydrous ethanol to deionized water is 1:3; the dosage ratio of ultrafine alloy powder to tetraethyl 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 dosage ratio of the ultrafine alloy powder to the ethanol solution is 1g:8mL; the mass ratio of the ultrafine alloy powder to N-(3-trimethoxysilylpropyl)ethylenediamine is 1:2.

[0073] Embodiment 6:

[0074] The difference between this embodiment and embodiment 5 is only the preparation of the soft magnetic composite material.

[0075] 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.

[0076] Comparative Example 1:

[0077] The difference between this comparative example and Example 2 is only the preparation of the soft magnetic composite material.

[0078] The preparation of the soft magnetic composite material was carried out under the same conditions as in Example 2 except that 3-aminobenzophenone was not added.

[0079] Comparative Example 2:

[0080] The difference between this comparative example and Example 2 is only the preparation of the soft magnetic composite material.

[0081] 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.

[0082] Comparative Example 3:

[0083] The difference between this comparative example and Example 5 is only the preparation of the soft magnetic composite material.

[0084] The preparation of the soft magnetic composite material was carried out under the same conditions as in Example 5 except that cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone were not added.

[0085] Experimental example:

[0086] 1. Material Characterization

[0087] The surface morphology of the soft magnetic composite material prepared in Example 1 was observed using a scanning electron microscope.

[0088] Figure 1 This is a 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.

[0089] 2. DC bias performance

[0090] 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.

[0091] Table 1 DC bias performance (%)

[0092]

[0093] As can be seen from Table 1, the DC bias performance of the soft magnetic composite material prepared in Examples 2-4 of the present invention is better than that of Example 1, because in the preparation of the soft magnetic composite material, Examples 2-4 first wrap the surface of the ultrafine alloy powder with a silicon dioxide coating layer, and then use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silicon dioxide coating layer; 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, 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 use of cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silicon dioxide coating layer can improve the DC bias performance of the soft magnetic composite material. The DC bias performance of the soft magnetic composite material prepared in Examples 2-4 of the present invention is better than that of Comparative Examples 1-2, because in the preparation of the soft magnetic composite material, Examples 2-4 use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica encapsulation layer, while Comparative Example 1 only uses cyclobutanetetracarboxylic dianhydride to modify the silica encapsulation layer, and Comparative Example 2 only uses 3-aminobenzophenone to modify the silica encapsulation layer. This shows that compared with using cyclobutanetetracarboxylic dianhydride or 3-aminobenzophenone alone to modify the silica encapsulation layer, using cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica encapsulation layer in combination can improve the DC bias performance of the soft magnetic composite material.

[0094] 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 encapsulation layer; 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 encapsulation layer, and does not use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica encapsulation layer. This shows that further use of N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica encapsulation layer can further improve the DC bias performance of the soft magnetic composite material.

[0095] 3. Quality factor

[0096] 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, with the quality factor test frequency being 1 MHz and the voltage being 250 mVac.

[0097] Table 2 Quality factors

[0098]

[0099] As can be seen from Table 2, the quality factor of the soft magnetic composite material prepared by Examples 2-4 of the present invention is better than that of Example 1, because in the preparation of the soft magnetic composite material, Examples 2-4 first wrap the surface of the ultrafine alloy powder with a silicon dioxide coating layer, and then use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silicon dioxide coating layer; the quality factor of the soft magnetic composite material prepared by Example 2 of the present invention is better than that of Examples 3-4, because in the preparation of the soft magnetic composite material, the amount of cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone used is different. This shows that the use of cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silicon dioxide coating layer can improve the quality factor of the soft magnetic composite material. The quality factor of the soft magnetic composite material prepared in Examples 2-4 of the present invention is better than that of Comparative Examples 1-2 because in the preparation of the soft magnetic composite material, Examples 2-4 use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica encapsulation layer, while Comparative Example 1 only uses cyclobutanetetracarboxylic dianhydride to modify the silica encapsulation layer, and Comparative Example 2 only uses 3-aminobenzophenone to modify the silica encapsulation layer. This shows that compared with using cyclobutanetetracarboxylic dianhydride or 3-aminobenzophenone alone to modify the silica encapsulation layer, using cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica encapsulation layer in combination can improve the quality factor of the soft magnetic composite material.

[0100] 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 encapsulation layer; 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 encapsulation layer, and does not use cyclobutanetetracarboxylic dianhydride and 3-aminobenzophenone to modify the silica encapsulation layer. This shows that further use of N-(3-trimethoxysilylpropyl)ethylenediamine to modify the silica encapsulation layer can further improve the quality factor of the soft magnetic composite material.

[0101] 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.

[0102] 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 protection scope of the present invention.

Claims

1. 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 100-3000nm; 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 cyclobutanetetracarboxylic acid dianhydride is 1:2-4, and the mass ratio of the ultrafine alloy powder to 3-aminobenzophenone is 1:2-4.

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

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

02.

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

02.

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

02.

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

02.

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

8. The method for preparing a soft magnetic composite material according to claim 1, characterized in that: The usage ratio of the ultrafine alloy powder to tetraethyl orthosilicate is 1g:1-2mL.

9. The soft magnetic composite material prepared by the preparation 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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