CN112071623A - Preparation method of soft magnetic material for high frequency - Google Patents
Preparation method of soft magnetic material for high frequency Download PDFInfo
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- CN112071623A CN112071623A CN202010977681.2A CN202010977681A CN112071623A CN 112071623 A CN112071623 A CN 112071623A CN 202010977681 A CN202010977681 A CN 202010977681A CN 112071623 A CN112071623 A CN 112071623A
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- soft magnetic
- magnetic material
- high frequency
- layered nickel
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
Abstract
A preparation method of a soft magnetic material for high frequency comprises the following steps: 1) grinding the iron magnetic powder and the layered nickel silicate in a mortar for 10-30min, sintering, cooling to room temperature, and grinding to obtain a material A (the layered nickel silicate compounded with the iron magnetic powder); 2) dispersing the material A into a functional polymer FPOSS-PS, stirring for 1-2 hours, and drying at 60-90 ℃ for 2-4 hours to obtain the high-frequency soft magnetic material. The layered nickel silicate can effectively compound the iron magnetic powder, so that the resistivity is obviously increased without changing the magnetic conductivity and the magnetic flux density; and the functionalized polymer can effectively coat the layered nickel silicate compounded with the iron magnetic powder, and hardly influences the magnetic conductivity and the magnetic flux density. The soft magnetic material prepared by the preparation method of the soft magnetic material for high frequency has excellent structure and performance, and can be applied to the field of microelectronics.
Description
Technical Field
The invention belongs to the technical field of magnetic materials, and particularly relates to a preparation method of a soft magnetic material for high frequency.
Background
The rapid development of the power electronic industry, namely a power transmission and transformation system which transmits power to high voltage and takes a transformer as a core; the power electronic frequency conversion equipment which is small in size and electronic components and takes an inductor and an electronic transformer as cores, namely the microelectronic field, faces the challenges of high frequency, high power conversion and high energy current density, and the development of soft magnetic materials cannot be separated. The high-frequency soft magnetic material is a main component for manufacturing devices such as high-power transformers, inductors, electronic transformers and the like, so the development level of the high-frequency soft magnetic material directly determines the development process of the power electronic field. The soft magnetic material has the advantages of low coercive force, low remanence, high saturation magnetization and the like, and is widely applied to the power electronic industry.
The common soft magnetic materials at present mainly comprise metal-based materials, soft magnetic ferrites, amorphous/nanocrystalline and soft magnetic composite materials, but the materials have limitations: the resistivity and the working frequency of the metal-based material are lower, and the high-frequency high-eddy current loss is extremely large; the saturation magnetization of the soft magnetic ferrite is too low; the amorphous/nanocrystalline material has high manufacturing cost, complex process and poor thermal stability; while soft magnetic composites have low magnetic permeability and flux density due to magnetic dilution effects.
Disclosure of Invention
Aiming at the problems in the prior art, the invention aims to provide a preparation method of a soft magnetic material for high frequency.
In order to achieve the purpose, the invention adopts the following technical means:
a preparation method of a soft magnetic material for high frequency comprises the following steps:
3) grinding the iron magnetic powder and the layered nickel silicate in a mortar for 10-30min, sintering, cooling to room temperature, and grinding to obtain a material A (the layered nickel silicate compounded with the iron magnetic powder);
4) dispersing the material A into a functional polymer FPOSS-PS, stirring for 1-2 hours, and drying at 60-90 ℃ for 2-4 hours to obtain the high-frequency soft magnetic material.
Further, 1) the medium iron magnetic powder and the layered nickel silicate are iron magnetic powder according to the mass ratio: 5-10:1 of layered nickel silicate; the sintering is carried out at the pressure of 400-600MPa, the heating rate of 100 ℃/min, the sintering temperature of 300-500 ℃ and the heat preservation time of 3-9 min.
Further, the iron magnetic powder comprises Fe-6.5Si micron powder and FeNi3And permalloy.
Further, in the step 2), the material A and the functional polymer FPOSS-PS are the following materials in percentage by mass: functionalized polymer 10-20: 1.
further, the functionalized polymer is prepared by the following method:
the method comprises the following steps: dissolving mono-hydroxy heptavinyl polyhedral oligomeric silsesquioxane (VPOSS-OH) and 2, 2-dimethoxy-2-phenylacetophenone (DMPA) into a mixed solvent of chloroform and trifluorotoluene (TFT) according to a volume ratio DMPA: TFT: 1:3, adding perfluorododecanethiol (F8-SH), reacting for 30min under the irradiation of an ultraviolet lamp of 365nm, removing the solvent, and purifying by using column chromatography to obtain FPOSS-OH;
step two: adding the FPOSS-OH, 4-oxo-4- (prop-2-alkynyl-1-oxy) butyric acid and DMAP (4-dimethylaminopyridine) obtained in the step one into a mixed solvent of DMPA and TFT according to the volume ratio of DMPA to TFT being 1:3, cooling to 0 ℃, adding N, N-diisopropyl carbodiimide (DIPC), reacting at room temperature for 24 hours after the addition is finished, and purifying by silica gel column chromatography to obtain FPOSS-alkyne;
step three: and (3) adding the FPOSS-alkyne obtained in the step two, azide-terminated polystyrene and cuprous bromide into the TFT, performing three freezing-vacuum-unfreezing cycles, adding pentamethyl diethylenetriamine (PMDETA) into a nitrogen atmosphere, reacting for 24 hours at room temperature, purifying by using a column chromatography after the reaction is finished, and drying to obtain the functional polymer FPOSS-PS.
In the first step, the mass ratio of VPOSS-OH to DMPA and F8-SH is VPOSS-OH: DMPA: F8-SH: 40:1:10.
In the second step, the mass ratio of FPOSS-OH to 4-oxo-4- (prop-2-ynyl-1-oxy) butanoic acid, DIPC and DMAP is FPOSS-OH: 4-oxo-4- (prop-2-ynyl-1-oxy) butanoic acid: DIPC: DMAP ═ 13:1:0.4: 0.2.
FPOSS-alkyne, azide-terminated polystyrene, cuprous bromide and PMDETA in the third step are mixed according to the mass ratio of FPOSS-alkyne: azide-terminated polystyrene: cuprous bromide: PMDETA ═ 1: 0.7: 0.03: 0.05.
the invention has the following beneficial effects: the layered nickel silicate has a layered structure and a larger specific surface area, and can effectively compound the ferromagnetic magnetic powder, so that the resistivity is obviously increased without changing the magnetic conductivity and the magnetic flux density, and the ferromagnetic magnetic powder and the layered nickel silicate have certain magnetic induction intensity, thereby effectively reducing the magnetic induction intensity loss in the material; furthermore, the functionalized polymer can effectively coat the layered nickel silicate compounded with the iron magnetic powder, and has almost no influence on magnetic conductivity and magnetic flux density. The soft magnetic material prepared by the preparation method of the soft magnetic material for high frequency has excellent structure and performance, and can be applied to the field of microelectronics.
Detailed Description
Preparation of the functionalized polymer: dissolving 4g of VPOSS-OH and 0.1g of DMPA into 40mL of mixed solvent of chloroform and TFT according to the volume ratio of DMPA to TFT being 1:3, adding 1g of F8-SH, then reacting for 30min under the irradiation of a 365nm ultraviolet lamp, removing the solvent, and purifying by column chromatography to obtain 16g of FPOSS-OH; then adding 16g of FPOSS-OH, 1.2g of 4-oxo-4- (prop-2-alkynyl-1-oxy) butyric acid and 0.3g of DMAP into 40mL of mixed solvent of DMPA and TFT according to the volume ratio of DMPA to TFT being 1:3, cooling to 0 ℃, adding 0.5g of DIPC, reacting at room temperature for 24h after the addition is finished, and purifying by silica gel column chromatography to obtain 12g of FPOSS-alkyne; adding 12g of FPOSS-alkyne, 8.4g of azide-terminated polystyrene and 0.4g of cuprous bromide into the TFT, carrying out three freezing-vacuum-unfreezing cycles, adding 0.6g of PMDETA in a nitrogen atmosphere, reacting at room temperature for 24 hours, purifying by using column chromatography after the reaction is finished, and drying to obtain 15g of functional polymer FPOSS-PS.
A preparation method of a soft magnetic material for high frequency comprises the following steps:
1) the method comprises the following steps of (1) taking the iron magnetic powder and the layered nickel silicate according to the mass ratio: 5-10:1 of layered nickel silicate is put into a mortar for grinding for 10-30min and then sintered at the pressure of 400-. Cooling to room temperature, and grinding to obtain material A (layered nickel silicate compounded with iron magnetic powder);
2) dispersing the material A into a functional polymer FPOSS-PS, stirring for 1-2 hours, and drying at 60-90 ℃ for 2-4 hours to obtain the high-frequency soft magnetic material.
Further, the iron magnetic powder in 1) comprises Fe-6.5Si micron powder and FeNi3And permalloy.
Further, in the step 2), the material A and the functional polymer FPOSS-PS are the following materials in percentage by mass: functionalized polymer 10-20: 1.
example 1
A preparation method of a soft magnetic material for high frequency comprises the following steps:
1) the Fe-6.5Si micron powder and the layered nickel silicate are mixed according to the mass ratio of Fe-6.5Si micron powder: and (3) grinding the layered nickel silicate 5:1 in a mortar for 10min, and then sintering, wherein the sintering pressure is 400MPa, the heating rate is 100 ℃/min, the sintering temperature is 300 ℃, and the heat preservation time is 9 min. Cooling to room temperature, and grinding to obtain material A (layered nickel silicate compounded with Fe-6.5Si micron powder);
2) dispersing the material A into a functional polymer FPOSS-PS, stirring for 1 hour, and drying at 60 ℃ for 4 hours to obtain the soft magnetic material for high frequency.
Further, in the step 2), the material A and the functional polymer FPOSS-PS are the following materials in percentage by mass: functionalized polymer 10: 1.
example 2
A preparation method of a soft magnetic material for high frequency comprises the following steps:
1) FeNi is mixed3And layered nickel silicate in a mass ratio of FeNi3: and (3) putting the layered nickel silicate 7:1 into a mortar for grinding for 20min, and then sintering at the temperature of 400 ℃ for 6min under the pressure of 500MPa at the temperature rise rate of 100 ℃/min. Cooling to room temperature and grinding to obtain material A (compounded with FeNi)3Layered nickel silicate of (1);
2) dispersing the material A into a functional polymer FPOSS-PS, stirring for 1.5 hours, and drying at 70 ℃ for 3 hours to obtain the soft magnetic material for high frequency.
Further, in the step 2), the material A and the functional polymer FPOSS-PS are the following materials in percentage by mass: functionalized polymer 15: 1.
example 3
A preparation method of a soft magnetic material for high frequency comprises the following steps:
1) the permalloy and the layered nickel silicate are prepared by the following steps of: 10:1 of layered nickel silicate is put into a mortar for grinding for 30min and then sintered, wherein the sintering pressure is 600MPa, the heating rate is 100 ℃/min, the sintering temperature is 500 ℃, and the heat preservation time is 3 min. Cooling to room temperature, and grinding to obtain material A (layered nickel silicate compounded with permalloy);
2) dispersing the material A into a functional polymer FPOSS-PS, stirring for 2 hours, and drying at 90 ℃ for 2 hours to obtain the soft magnetic material for high frequency.
Further, in the step 2), the material A and the functional polymer FPOSS-PS are the following materials in percentage by mass: functionalized polymer 10-20: 1.
comparative example 1
The Fe-6.5Si micron powder and the layered nickel silicate are mixed according to the mass ratio of Fe-6.5Si micron powder: and (3) grinding the layered nickel silicate 5:1 in a mortar for 10min, and then sintering, wherein the sintering pressure is 400MPa, the heating rate is 100 ℃/min, the sintering temperature is 300 ℃, and the heat preservation time is 9 min. Cooling to room temperature and grinding to obtain the high-frequency soft magnetic material.
Comparative example 2
Dispersing Fe-6.5Si micron powder into a functional polymer FPOSS-PS, stirring for 1 hour, and drying at 60 ℃ for 4 hours to obtain the soft magnetic material for high frequency.
Wherein the Fe-6.5Si micron powder and the functional polymer FPOSS-PS are Fe-6.5Si micron powder according to the mass ratio: functionalized polymer 10: 1.
comparative example 3
The commercially available Fe-6.5Si micron powder is used as the soft magnetic material for high frequency.
The ferrite magnetic materials prepared in examples 1 to 3 and comparative examples 1 to 3 were subjected to performance tests, and the results of the tests are shown in table 1.
Table 1 results of performance testing
As can be seen from the content in table 1, the initial permeability of the ferrite magnetic material with high permeability prepared by the present invention is 50000, which is a ferrite magnetic material with high permeability. The layered nickel silicate has a layered structure and a larger specific surface area, so that the ferromagnetic magnetic powder can be effectively compounded, the resistivity is obviously increased without changing the magnetic conductivity and the magnetic flux density, and the ferromagnetic magnetic powder and the layered nickel silicate have certain magnetic induction intensity, so that the magnetic induction intensity loss in the material is effectively reduced; furthermore, the functionalized polymer can effectively coat the layered nickel silicate compounded with the iron magnetic powder, almost has no influence on magnetic conductivity and magnetic flux density, and the functionalized polymer and the magnetic flux density are simultaneously used for improving the magnetic conductivity of the ferrite material and have a synergistic effect. The soft magnetic material for high frequency prepared by the process method has excellent performance of high magnetic permeability.
Claims (8)
1. A method for preparing a soft magnetic material for high frequency, characterized by comprising the steps of:
1) grinding the iron magnetic powder and the layered nickel silicate in a mortar for 10-30min, sintering, cooling to room temperature, and grinding to obtain a material A (the layered nickel silicate compounded with the iron magnetic powder);
2) dispersing the material A into a functional polymer FPOSS-PS, stirring for 1-2 hours, and drying at 60-90 ℃ for 2-4 hours to obtain the high-frequency soft magnetic material.
2. The method for producing a soft magnetic material for high frequency according to claim 1, wherein 1) the ferromagnetic magnetic powder and the layered nickel silicate are, in mass ratio, ferromagnetic magnetic powder: 5-10:1 of layered nickel silicate; the sintering is carried out at the pressure of 400-600MPa, the heating rate of 100 ℃/min, the sintering temperature of 300-500 ℃ and the heat preservation time of 3-9 min.
3. The method for producing a soft magnetic material for high frequency as claimed in claim 1, wherein the ferromagnetic magnetic powder in 1) comprises Fe-6.5Si micron powder, FeNi3And permalloy.
4. The method for preparing a soft magnetic material for high frequency according to claim 1, wherein the material a and the functionalized polymer FPOSS-PS in the 2) are, by mass, the following components: functionalized polymer 10-20: 1.
5. the method for producing a soft magnetic material for high frequency according to claim 1, wherein the functionalized polymer in 2) is produced by the following method:
the method comprises the following steps: dissolving mono-hydroxy heptavinyl polyhedral oligomeric silsesquioxane (VPOSS-OH) and 2, 2-dimethoxy-2-phenylacetophenone (DMPA) into a mixed solvent of chloroform and trifluorotoluene (TFT) according to a volume ratio DMPA: TFT: 1:3, adding perfluorododecanethiol (F8-SH), reacting for 30min under the irradiation of an ultraviolet lamp of 365nm, removing the solvent, and purifying by using column chromatography to obtain FPOSS-OH;
step two: adding the FPOSS-OH, 4-oxo-4- (prop-2-alkynyl-1-oxy) butyric acid and DMAP (4-dimethylaminopyridine) obtained in the step one into a mixed solvent of DMPA and TFT according to the volume ratio of DMPA to TFT being 1:3, cooling to 0 ℃, adding N, N-diisopropyl carbodiimide (DIPC), reacting at room temperature for 24 hours after the addition is finished, and purifying by silica gel column chromatography to obtain FPOSS-alkyne;
step three: and (3) adding the FPOSS-alkyne obtained in the step two, azide-terminated polystyrene and cuprous bromide into the TFT, performing three freezing-vacuum-unfreezing cycles, adding pentamethyl diethylenetriamine (PMDETA) into a nitrogen atmosphere, reacting for 24 hours at room temperature, purifying by using a column chromatography after the reaction is finished, and drying to obtain the functional polymer FPOSS-PS.
6. The method for producing a soft magnetic material for high frequency as claimed in claim 5, wherein in the first step, VPOSS-OH is mixed with DMPA and F8-SH in a mass ratio of VPOSS-OH: DMPA: F8-SH: 40:1:10.
7. A method of producing a soft magnetic material for high frequency signals as claimed in claim 5, wherein in the second step, FPOSS-OH is mixed with 4-oxo-4- (prop-2-ynyl-1-oxy) butanoic acid, DIPC and DMAP at a mass ratio of FPOSS-OH: 4-oxo-4- (prop-2-ynyl-1-oxy) butanoic acid: DIPC: DMAP ═ 13:1:0.4: 0.2.
8. The method for producing a soft magnetic material for high frequencies according to claim 5, wherein FPOSS-alkyne, azide-terminated polystyrene, cuprous bromide and PMDETA in the third step are mixed in a mass ratio of FPOSS-alkyne: azide-terminated polystyrene: cuprous bromide: PMDETA ═ 1: 0.7: 0.03: 0.05.
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| US4820552A (en) * | 1987-06-22 | 1989-04-11 | Espinosa C Jose G | Coated zinc, chemistry and manufacturing process |
| EP1168381A2 (en) * | 2000-06-30 | 2002-01-02 | Robert Bosch Gmbh | Soft magnetic material with heterogenous structure and its production process |
| CN105448447A (en) * | 2015-11-27 | 2016-03-30 | 天津大学 | Soft magnetic composite material and preparation method therefor |
| CN105873697A (en) * | 2013-12-20 | 2016-08-17 | 霍加纳斯股份有限公司 | Soft magnetic powder mix |
| CN107492433A (en) * | 2017-07-05 | 2017-12-19 | 安徽江威精密制造有限公司 | A kind of iron-based soft magnetic composite of doping vario-property nickel powder and preparation method thereof |
| CN108074723A (en) * | 2016-11-18 | 2018-05-25 | 贵州华磁电子科技有限公司 | High magnetic core for transformer of a kind of magnetic conductivity and preparation method thereof |
| CN109599244A (en) * | 2018-12-17 | 2019-04-09 | 戴爱娟 | A kind of preparation method of iron nickel soft magnetic materials |
| CN111068734A (en) * | 2019-12-24 | 2020-04-28 | 新疆大学 | Bamboo-like nitrogen-doped carbon nanofiber-coated transition metal alloy nanoparticle catalytic material for efficient bifunctional electrocatalysis |
-
2020
- 2020-09-17 CN CN202010977681.2A patent/CN112071623A/en not_active Withdrawn
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4820552A (en) * | 1987-06-22 | 1989-04-11 | Espinosa C Jose G | Coated zinc, chemistry and manufacturing process |
| EP1168381A2 (en) * | 2000-06-30 | 2002-01-02 | Robert Bosch Gmbh | Soft magnetic material with heterogenous structure and its production process |
| CN105873697A (en) * | 2013-12-20 | 2016-08-17 | 霍加纳斯股份有限公司 | Soft magnetic powder mix |
| CN105448447A (en) * | 2015-11-27 | 2016-03-30 | 天津大学 | Soft magnetic composite material and preparation method therefor |
| CN108074723A (en) * | 2016-11-18 | 2018-05-25 | 贵州华磁电子科技有限公司 | High magnetic core for transformer of a kind of magnetic conductivity and preparation method thereof |
| CN107492433A (en) * | 2017-07-05 | 2017-12-19 | 安徽江威精密制造有限公司 | A kind of iron-based soft magnetic composite of doping vario-property nickel powder and preparation method thereof |
| CN109599244A (en) * | 2018-12-17 | 2019-04-09 | 戴爱娟 | A kind of preparation method of iron nickel soft magnetic materials |
| CN111068734A (en) * | 2019-12-24 | 2020-04-28 | 新疆大学 | Bamboo-like nitrogen-doped carbon nanofiber-coated transition metal alloy nanoparticle catalytic material for efficient bifunctional electrocatalysis |
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