阅读说明：本技术 一种具有低磁滞损耗的金属软磁复合材料 (Metal soft magnetic composite material with low hysteresis loss ) 是由 冯双久 倪江利 胡锋 阚绪材 刘先松 杨玉杰 吕庆荣 朱瑞威 于 2020-11-02 设计创作，主要内容包括：本发明公开了一种具有低磁滞损耗的金属软磁复合材料,包括金属软磁复合材料和永磁铁氧体材料。涉及具有低磁损耗的软磁材料技术领域,本发明产品在相同的测试条件下,通过本发明方法制得的金属软磁复合材料损耗降低,主要是磁滞损耗的降低,涡流损耗系数基本保持不变。(The invention discloses a metal soft magnetic composite material with low hysteresis loss, which comprises a metal soft magnetic composite material and a permanent magnetic ferrite material. The invention relates to the technical field of soft magnetic materials with low magnetic loss, and the product of the invention reduces the loss of the metal soft magnetic composite material prepared by the method under the same test condition, mainly reduces the hysteresis loss, and basically keeps the eddy current loss coefficient unchanged.)

1. The metal soft magnetic composite material with low hysteresis loss is characterized by comprising a metal soft magnetic composite material and a permanent magnetic material, and is magnetized and magnetized in an external magnetic field.

2. The metallic soft magnetic composite material with low hysteresis loss according to claim 1, wherein the metallic soft magnetic composite magnetic core is a ferrite powder core, a FeSiAl powder core, a FeSi powder core, a FeSiCr powder core or an amorphous nanocrystalline powder core.

3. The metal soft magnetic composite material with low hysteresis loss according to claim 1, wherein the permanent magnetic material is strontium ferrite powder, barium ferrite powder or other metal permanent magnetic material powder.

4. The metallic soft magnetic composite material with low hysteresis loss according to claim 1, wherein the release agent used in the composite material is zinc stearate.

5. The preparation method of the metal soft magnetic composite material with low hysteresis loss as claimed in claim 1, wherein the metal soft magnetic composite material powder is used as a raw material, 0.5 wt% -15 wt% of permanent magnetic powder is added and mixed, 0.5 wt% of zinc stearate is additionally added as a release agent, the powder is molded into a powder core under the pressure of 500-.

6. The method for preparing the metallic soft magnetic composite material with low hysteresis loss according to claim 5, wherein the pressure is 1500MPa, and the heat treatment temperature is 650 ℃.

Technical Field

The invention relates to the field of metal soft magnetic composite materials, in particular to a metal soft magnetic composite material with low hysteresis loss.

Background

The soft magnetic composite material is a functional material widely applied to the field of power electronics, and is mainly applied to various magnetic devices such as high-power inductors, transformers and the like. Due to the high saturation magnetization and large resistivity of the material, the material is widely applied to high-power electronic systems in a kilohertz frequency band. When the magnetic material is applied to an alternating electromagnetic field, loss is generated, and the loss not only consumes electromagnetic energy, but also causes the problems of heating and warming of a system and heat dissipation. From an application point of view, the losses are naturally as low as possible, but it is theoretically impossible to completely eliminate them analytically. Therefore, the loss characteristic becomes an important technical index of the soft magnetic material under the condition of high power, and the loss of the material is gradually reduced along with the development of the technology. The real large-scale research and application history of the soft magnetic composite material is only 20 years, but the soft magnetic composite material is good in material loss reduction, which benefits from the reference of ferrite material research on one hand and is also related to the improvement of the process conditions of material preparation on the other hand. Two major sources of soft magnetic composite losses are currently addressed: the hysteresis loss and the eddy current loss respectively and purposefully adopt different technical means to reduce the loss. For the reduction of hysteresis loss, two methods are frequently adopted, one is to improve the density of the composite material, thereby effectively improving the magnetic conductivity of the material and achieving the purpose of reducing the hysteresis loss; the other is to eliminate the stress existing in the material by annealing treatment, and eliminate the hysteresis loss caused by the stress as much as possible. The eddy current loss can be divided into eddy current loss in metal particles and eddy current loss between particles. Eddy current loss in the particles is reduced by increasing the resistivity of the alloy; on the other hand, eddy current losses can also be reduced by refining the alloy particles. The eddy current loss among the particles is realized by coating the insulating material layer on the surface of the metal magnetic particles, so that the insulation among different metal particles is realized, the flow of eddy current among different metal particles is prevented, and the eddy current loss is reduced. These methods for reducing loss are mutually restricted, for example, refining metal particles has a remarkable effect of reducing eddy current loss, but the particles are fine, which is not favorable for improving the magnetic permeability of the composite material, and increases hysteresis loss. Therefore, various factors and specific application conditions are comprehensively considered in actual production so as to obtain the lowest material loss.

The amorphous nanocrystalline soft magnetic material firstly proposed by Japanese scientists realizes one-time jump of the performance of the metal soft magnetic material, and the material has larger resistivity and proper magnetic conductivity by distributing nano-sized micro crystal grains in the amorphous material, so that the mutual restriction of hysteresis loss and eddy current loss of the material is well balanced, and the metal soft magnetic material with excellent performance is formed. However, the amorphous nanocrystalline metal powder has small particles due to the limitation of the preparation process, the prepared soft magnetic composite material has low magnetic conductivity, and the hysteresis loss cannot be effectively controlled. In addition, the amorphous nanocrystalline has high cost, which limits the application field.

In high and new technical fields such as high-power supplies, new energy electric vehicles, wind power generation, high-speed rails, rail transit and the like, the demand for novel magnetic devices is strong. However, these devices have high technical requirements, and in some cases, the device cannot function because of large material loss. The reduction of the losses of the soft magnetic composite material is not aimed at saving the point of energy lost by the material, but may provide more freedom for the design of high power devices and equipment. For example, the maximum power of a high-power UPS power supply in the world is 60kW, and the reason for limiting further increase of power capacity of the power supply is that the heat dissipation problem of heat generation due to internal loss of the power supply cannot be solved.

Heretofore, we have proposed a method (application No. 202010376507.2) for reducing the magnetic loss of a metal soft magnetic composite material by applying a magnetic field, which has the disadvantage that the magnetic field is provided by a permanent magnet, which increases the volume and cost of an inductive device. The invention is an improvement on the basis of the invention, and the external magnetic field is changed into the internal magnetic field, so that the volume and the cost of the inductive device are not increased basically.

Disclosure of Invention

The invention aims to provide a metal soft magnetic composite material with low hysteresis loss, which is prepared by mixing metal soft magnetic material powder and permanent magnetic material powder, magnetizing the metal soft magnetic composite material under an external magnetic field to magnetize the permanent magnetic material powder and provide a magnetic field, so that the loss of the material can be further reduced, and the metal soft magnetic composite material with low loss is obtained.

In order to achieve the purpose, the invention provides the following technical scheme:

a metal soft magnetic composite material with low hysteresis loss comprises a metal soft magnetic composite material and a permanent magnetic material, and is magnetized and magnetized in an external magnetic field.

The magnetic core made of the metal soft magnetic composite material is an iron powder core, a FeSiAl powder core, a FeSi powder core, a FeSiCr powder core or an amorphous nanocrystalline powder core.

The permanent magnetic material is strontium ferrite powder, barium ferrite powder or other metal permanent magnetic material powder.

The release agent used by the composite material is zinc stearate.

A preparation method of a metal soft magnetic composite material with low hysteresis loss comprises the steps of taking metal soft magnetic composite material powder as a raw material, adding 0.5 wt% -15 wt% of permanent magnetic powder, mixing, additionally adding 0.5 wt% of zinc stearate as a release agent, forming the powder into a powder core under the pressure of 500 plus 1800MPa, placing the powder core in a vacuum furnace, and magnetizing the metal powder core material subjected to heat treatment for 1 hour at the temperature of 200 plus 700 ℃ in a magnetic field of 1-2MA/m to obtain a metal powder core material finished product.

The pressure is 1500MPa, and the heat treatment temperature is 650 ℃.

Compared with the prior art, the invention has the following beneficial effects:

under the same test condition, the loss of the soft magnetic composite material prepared by the method is reduced, mainly the hysteresis loss is reduced, the maximum loss can be reduced by more than 70 percent, and the eddy current loss coefficient is basically kept unchanged.

Drawings

FIG. 1 shows the comparison of the losses before and after the magnetization of FeSi and strontium ferrite composites at 100kHz and 100 mT.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to specific embodiments, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and 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:

spherical FeSi6.5wt% powder with the average particle size of 50 mu m is used as a raw material, 8.1 wt% strontium ferrite powder is added and mixed, 0.5 wt% zinc stearate is additionally added to be used as a release agent, and the powder is molded into an annular powder core with the outer diameter of 27mm, the inner diameter of 15mm and the height of about 10mm under the pressure of 1500 MPa. And (3) placing the FeSi powder core in a vacuum furnace, and carrying out heat treatment at 220 ℃ for 1 hour to obtain a powder core material finished product.

The magnetic measurement result shows that the specific saturation magnetization of the material reaches 198emu/g, the initial permeability is 26, and the loss at 100kHz and 100mT is 5500kW/m³After magnetization, the loss under the same test conditions is reduced to 3870kW/m³The amplitude reduction is 29.7%. FIG. 1 shows a comparison of the relationship between the power consumption and the frequency of the sample before and after magnetization, from which it can be found that FeSi/SrFe after magnetization₁₂O₁₉The powder core is obviously reduced compared with the powder core before magnetization.

Example 2

Mechanically crushed FeSiAl powder with the average grain diameter of 30 mu m is used as a raw material, 10 wt% of strontium ferrite powder is added for mixing, 2 wt% of low-temperature glass powder is added as a bonding agent, 0.5 wt% of zinc stearate is used as a release agent, and the powder is molded into an annular powder core under the pressure of 1800 MPa. And (3) placing the FeSiAl powder core in a vacuum furnace, and carrying out heat treatment at 600 ℃ for 1 hour to obtain a finished product of the magnetic powder core material.

The magnetic powder core has saturation magnetization of 123emu/g, magnetic conductivity of 47, 100kHz, and loss of 382kW/m at 50mT³. After magnetization under the magnetic field of 1.5T, the magnetic permeability is 44.7, 100kHz and the loss under 50mT is 268kW/m³The decrease is 30%.

Example 3

Spherical FeSiAl powder with the average particle size of 50 mu m is used as a raw material, 10.6 wt% of strontium ferrite powder with the average particle size of 1 mu m is added and mixed, 0.5 wt% of zinc stearate is added as a release agent, and the powder is molded into an annular powder core under the pressure of 1800 MPa. And (3) placing the FeSiAl powder core in a vacuum furnace, and carrying out heat treatment in vacuum at 630 ℃ for 2 hours to obtain a finished product of the magnetic powder core material.

The magnetic permeability of the magnetic powder core is 32.5, 100kHz, and the loss at 50mT is 492kW/m 3. After magnetization at 1.5T, the permeability was 29, 100kHz, and the loss at 50mT was 265kW/m3, which decreased by 46%.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.