阅读说明：本技术 一种夹心电感及其磁芯材料 (Sandwich inductor and magnetic core material thereof ) 是由 冯双久 倪江利 刘先松 阚绪材 朱守金 赵幸丽 李勇 于 2021-08-02 设计创作，主要内容包括：本发明提供一种夹心电感及其磁芯材料,涉及软磁复合材料加工技术领域。所述夹心电感及其磁芯材料为FeAlSi/六方氮化硼复合材料,其制备方法主要包括：物料按一定比例混合后,在球磨机中,球磨2h,然后放在烘箱里烘干,在一定压力下成型,在真空下最佳退火。本发明克服了现有技术的不足,通过对电感磁芯材料内部结构进行改造有效降低球形颗粒之间的涡流损耗,同时在绕线后的电感两侧加上永磁铁,降低电感磁滞损耗,是电感整体性能带来极大提高。(The invention provides a sandwich inductor and a magnetic core material thereof, and relates to the technical field of soft magnetic composite material processing. The sandwich inductor and the magnetic core material thereof are FeAlSi/hexagonal boron nitride composite materials, and the preparation method mainly comprises the following steps: mixing the materials according to a certain proportion, ball-milling for 2h in a ball mill, then drying in an oven, forming under a certain pressure, and optimally annealing under vacuum. The invention overcomes the defects of the prior art, effectively reduces the eddy current loss among spherical particles by modifying the internal structure of the inductance magnetic core material, and simultaneously reduces the hysteresis loss of the inductance by adding the permanent magnets on two sides of the wound inductance, thereby greatly improving the overall performance of the inductance.)

1. A sandwich inductor is characterized in that after a coil is wound on an inductor magnetic core body, permanent magnetic sheets are arranged on the upper surface and the lower surface of the magnetic core body wound with the coil and are fixed through a fixing clamp; the permanent magnet sheets are ferrite permanent magnets or metal permanent magnets.

2. A magnetic core material for a sandwich inductor according to claim 1, wherein: the magnetic core material comprises FeAlSi and HBN (hexagonal boron nitride), wherein the HBN (hexagonal boron nitride) accounts for 1-3% by mass.

3. The sandwich inductor and magnetic core material thereof according to claim 1, wherein the composite material comprises HBN (hexagonal boron nitride) in an amount of 2% by mass.

4. A method for preparing a magnetic core material according to claim 2 or 3, characterized in that: the preparation method of the magnetic core material comprises the following steps:

(1) mixing the prepared materials according to the mass percentage, ball-milling for 1-3h in a ball mill at the rotating speed of 130-;

(2) drying the material obtained in the step (1) in an oven;

(3) putting the material obtained in the step (2) into a mold, adding a release agent into the mold, and molding under the pressure of 1600-2000 MPa;

(4) annealing the formed material in vacuum at the temperature of 600-850 ℃ to finally obtain the composite material.

5. The method for producing a magnetic core material according to claim 4, characterized in that: the composite powder obtained by mechanical grinding in the step (1) has an average particle size of 50 μm.

6. The method for producing a magnetic core material according to claim 4, characterized in that: and (2) ball milling is carried out in the step (1) for 2 hours at a rotating speed of 160 r/min.

7. The method for producing a magnetic core material according to claim 4, characterized in that: the pressure in the step (3) is 1800 MPa.

8. The method for producing a magnetic core material according to claim 4, characterized in that: the release agent added in the step (3) is zinc stearate, and the addition amount of the release agent is 0.5 percent of the mass percentage of the passivation raw material.

9. The method for producing a magnetic core material according to claim 4, characterized in that: and (4) carrying out vacuum annealing at 740 ℃.

Technical Field

The invention relates to the technical field of processing of soft magnetic composite materials, in particular to a sandwich inductor and a magnetic core material thereof.

Background

Soft magnetic composite materials are widely used in magnetic devices due to their excellent properties, including high permeability and low core loss. With the development of miniaturization and high frequency of power electronic equipment, magnetic devices are also developing toward high frequency, high power, low power consumption and good electromagnetic compatibility.

The prior documents have disclosed a number of methods relating to the use of different materials to form insulating layers between ferromagnetic metal particles to reduce eddy current losses in composite materials; wherein glass is used as an insulating agent to reduce eddy current losses; although the eddy current loss can be reduced by adding the insulating material, the introduction of the insulating material can cause the reduction of the magnetic permeability and the saturation magnetization, and the performance of the soft magnetic composite material is weakened; meanwhile, the maximum power of the high-power UPS is 60kW, and the reason for limiting the further improvement of the power capacity of the power supply is that the heat dissipation problem of loss and heating inside the power supply cannot be solved; eddy current loss of the core material itself, which is one of the losses, and hysteresis loss, which is another aspect; how to modify the structure and the material of the existing inductor to reduce the internal loss to the maximum extent is the technical problem to be solved by the invention.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a sandwich inductor and a magnetic core material thereof, solves the problems of loss and heating of a high-power inductor, effectively reduces eddy current loss among spherical particles by modifying the internal structure of the inductor magnetic core material, and reduces inductance hysteresis loss by adding permanent magnets on two sides of the wound inductor, thereby greatly improving the overall performance of the inductor.

Greatly improving the practical application value of the product.

In order to achieve the above purpose, the technical scheme of the invention is realized by the following technical scheme:

after a coil is wound on an inductance magnetic core body, permanent magnetic sheets are arranged on the upper surface and the lower surface of the magnetic core body wound with the coil and are fixed through a fixing clamp; the permanent magnet sheets are ferrite permanent magnets or metal permanent magnets.

The magnetic core material of the sandwich inductor comprises FeAlSi and HBN (hexagonal boron nitride), wherein the HBN (hexagonal boron nitride) accounts for 1-3% by mass.

The composite material contains 2% of HBN (hexagonal boron nitride) in percentage by mass.

The preparation method of the magnetic core material comprises the following steps:

(1) mixing the prepared materials according to the mass percentage, ball-milling for 1-3h in a ball mill at the rotating speed of 130-;

(2) drying the material obtained in the step (1) in an oven;

(3) putting the material obtained in the step (2) into a mold, adding a release agent into the mold, and molding under the pressure of 1600-2000 MPa;

(4) annealing the formed material in vacuum at the temperature of 600-850 ℃ to finally obtain the composite material.

A method for producing a magnetic core material, wherein the composite powder obtained by mechanical grinding in the step (1) has an average particle diameter of 50 μm.

The preparation method of the magnetic core material comprises the step (1) of ball milling for 2 hours at the rotating speed of 160 r/min.

The preparation method of the magnetic core material comprises the step (3) of pressing 1800 Mpa.

In the preparation method of the magnetic core material, the release agent added in the step (3) is zinc stearate, and the addition amount of the release agent is 0.5 percent of the mass percentage of the passivation raw material.

And (3) a preparation method of the magnetic core material, wherein in the step (4), the vacuum annealing temperature is up to 740 ℃.

The invention provides a sandwich inductor and a magnetic core material thereof and a preparation method thereof, and compared with the prior art, the sandwich inductor and the magnetic core material have the advantages that:

under the same condition, the magnetic conductivity is unchanged, a layer of insulating material is coated outside FeAlSi particles to increase the resistivity, and the eddy current loss among the particles is effectively reduced; because the hexagonal boron nitride is of a layered structure, after the layered structure is opened, FeAlSi particles are coated outside, so that the eddy current loss is reduced, and the loss can be effectively reduced in a high-power electrical system; and meanwhile, permanent magnets are added on two sides of the inductor after winding, so that the hysteresis loss of the inductor is reduced, and the overall performance of the inductor is greatly improved.

Description of the drawings:

FIG. 1: the magnetic core material is a FeAlSi electron microscope scanning image without adding hexagonal boron nitride;

FIG. 2: the magnetic core material is a FeAlSi electron microscope scanning image without adding hexagonal boron nitride;

FIG. 3: adding FeAlSi electron microscope scanning picture of hexagonal boron nitride into the magnetic core material;

FIG. 4: the power loss of the composite material obtained by measuring the hexagonal boron nitride with different contents under the condition that the frequency of the magnetic core material is continuously increased;

FIG. 5: the power loss of the composite material obtained by measuring different contents of hexagonal boron nitride under the conditions of frequency (f) of 100kHz and magnetic induction intensity (Bm) of 100mT by using the magnetic core material of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

the sandwich inductor and the magnetic core material thereof comprise FeAlSi and HBN (hexagonal boron nitride), wherein the HBN (hexagonal boron nitride) accounts for 1% by mass; the preparation method of the composite material comprises the following steps:

(1) mixing the prepared materials according to the mass percentage, ball-milling for 2 hours in a ball mill by using alcohol as a solvent after mixing, wherein the rotating speed is 150 r/min;

(2) drying the material obtained in the step (1) in an oven;

(3) putting the material obtained in the step (2) into a mold, adding a release agent into the mold, and molding under the pressure of 1800 Mpa;

(4) and annealing the formed material in vacuum at 740 ℃, and finally obtaining the composite material.

Example 2:

according to the preparation method described in the above example 1, 2% of hexagonal boron nitride was added to prepare FeAlSi/hexagonal boron nitride composite powder, and then scanning by electron microscope was performed, and the result is shown in fig. 2;

as can be seen from fig. 1 and 2, the particles in the mixed powder are coated, and the spherical particles are blocked from each other and the eddy current loss therebetween is reduced as compared with the conventional spherical particles.

Example 3:

detecting the magnetic permeability of the FeAlSi/hexagonal boron nitride composite material under the conditions that the mass percent of the hexagonal boron nitride is 0%, 1%, 2% and 3%, wherein the results are shown as follows;

the magnetic loss of FeAlSi/hexagonal boron nitride composite materials prepared from 0%, 1%, 2% and 3% of hexagonal boron nitride in different test environments is detected, and the results are shown in the following table:

it can be seen from the above table that the hysteresis loss of the sample is lowest when the hexagonal boron nitride content is 1%.

Example 4: the material of embodiment 1 is made into a circular magnetic core 1, a winding is wound on the magnetic core, permanent magnetic sheets 2 are arranged on the upper surface and the lower surface of a magnetic core body wound with a coil and are fixed through a fixing clamp, and the product loss is measured.

In conclusion, under the same condition, the magnetic permeability is unchanged, the FeAlSi particles are coated with a layer of insulating material to increase the resistivity, and the eddy current loss between the particles is effectively reduced. It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.