CN102964116A - Wide-temperature range high DC superimposed soft magnetic ferrite - Google Patents
Wide-temperature range high DC superimposed soft magnetic ferrite Download PDFInfo
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- CN102964116A CN102964116A CN2012103859997A CN201210385999A CN102964116A CN 102964116 A CN102964116 A CN 102964116A CN 2012103859997 A CN2012103859997 A CN 2012103859997A CN 201210385999 A CN201210385999 A CN 201210385999A CN 102964116 A CN102964116 A CN 102964116A
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- Prior art keywords
- soft magnetic
- magnetic ferrite
- ferrite
- wide temperature
- principal constituent
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- 229910000859 α-Fe Inorganic materials 0.000 title claims abstract description 45
- 239000000470 constituent Substances 0.000 claims description 16
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 12
- 229910052760 oxygen Inorganic materials 0.000 claims description 12
- 239000001301 oxygen Substances 0.000 claims description 12
- 238000002360 preparation method Methods 0.000 claims description 11
- 238000005245 sintering Methods 0.000 claims description 8
- 239000002002 slurry Substances 0.000 claims description 8
- 239000011230 binding agent Substances 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 4
- 238000003801 milling Methods 0.000 claims description 4
- 239000003595 mist Substances 0.000 claims description 4
- 238000002156 mixing Methods 0.000 claims description 4
- 239000004576 sand Substances 0.000 claims description 4
- 238000000748 compression moulding Methods 0.000 claims description 3
- 230000035699 permeability Effects 0.000 abstract description 26
- 239000000463 material Substances 0.000 abstract description 13
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 abstract 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 abstract 2
- ZKATWMILCYLAPD-UHFFFAOYSA-N niobium pentoxide Chemical compound O=[Nb](=O)O[Nb](=O)=O ZKATWMILCYLAPD-UHFFFAOYSA-N 0.000 abstract 2
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 abstract 1
- 229910000019 calcium carbonate Inorganic materials 0.000 abstract 1
- 235000010216 calcium carbonate Nutrition 0.000 abstract 1
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 abstract 1
- 239000000377 silicon dioxide Substances 0.000 abstract 1
- 235000012239 silicon dioxide Nutrition 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 239000000203 mixture Substances 0.000 description 6
- 238000012360 testing method Methods 0.000 description 6
- 239000013078 crystal Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 239000000411 inducer Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- WJZHMLNIAZSFDO-UHFFFAOYSA-N manganese zinc Chemical class [Mn].[Zn] WJZHMLNIAZSFDO-UHFFFAOYSA-N 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000007634 remodeling Methods 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Landscapes
- Magnetic Ceramics (AREA)
- Soft Magnetic Materials (AREA)
Abstract
The invention relates to the technical field of soft magnetic ferrite material production, in particular to a wide-temperature range high DC (direct current) superimposed soft magnetic ferrite. The wide-temperature range high DC superimposed soft magnetic ferrite disclosed in the invention is composed of principal components and minor components. The principal components comprise: 53.2-56.1mol% of Fe2O3, 2.5-10.5mol% of ZnO, less than or equal to 5mol% of NiO, and the balance MnO. In terms of the total weight of the principal components, the minor components comprise: 50-200ppm of SiO2, 200-1500ppm of CaCO3, 50-500ppm of ZrO2, 50-500ppm of Nb2O5, and 50-300ppm of Na2O. Under a DC superimposed magnetic field of 100A/m and a temperature of 25DEG C, the soft magnetic ferrite provided in the invention has incremental permeability micro delta over 600, and under 100DEG C, the incremental permeability micro delta can be over 300.
Description
Technical field
The present invention relates to the soft magnetic ferrite production technical field, particularly the high DC stacked soft magnetic ferrite of a kind of wide temperature.
Background technology
The MnZn ferrite is widely used in electronics, communication field as supply transformer and material for inductor.The ferrite core that uses as inducer, during its work except high frequency ac signal is arranged, toward contact certain DC component that will superpose.Require ferrite core that larger incremental permeability μ is arranged this moment
Δ, keep inductance stabilization to guarantee inducer, be unlikely to inductance and descend more and cisco unity malfunction.Simultaneously, for the inducer of outwork, not only require to keep stable inductance under its normal temperature, also require to keep stable inductance under its high temperature.This just requires ferrite core all will have higher incremental permeability μ under normal temperature, high temperature
Δ
Chinese invention patent CN1686930A has announced a kind of high additivity ferrite in manganese zinc series and preparation method thereof, by Fe
2O
3The content content that is limited in 51～56mol%, ZnO be limited in 6 ~ 12mol% scope, realized the height stack performance of material.Chinese invention patent CN101183581A has announced a kind of high DC stacked MnZn high magnetic conductivity ferrite and preparation method thereof, by Fe
2O
3The content content that is limited in 52～53mol%, ZnO be limited in 19 ~ 20mol% scope, realized the height stack performance of material.But above-mentioned materials incremental permeability under wide temperature condition is not good.Therefore, the needs exploitation is a kind of all will have high incremental permeability μ under normal temperature, high temperature
ΔThe MnZn Ferrite Material.
Summary of the invention
The object of the present invention is to provide and a kind ofly under normal temperature, high temperature, all will have high incremental permeability μ
ΔThe high DC stacked soft magnetic ferrite of wide temperature, under the DC stacked magnetic field of 100A/m, the incremental permeability μ under 25 ℃
ΔMore than 600, the incremental permeability μ under 100 ℃
ΔMore than 300.
The technical solution adopted for the present invention to solve the technical problems is: the high DC stacked soft magnetic ferrite of a kind of wide temperature, and the high DC stacked soft magnetic ferrite of described wide temperature is comprised of principal constituent and minor component, and the molar percentage of each component of described principal constituent is: Fe
2O
353.2-56.1mol%, ZnO 2.5-10.5mol%, NiO≤5mol%, MnO surplus; By accounting for the principal constituent gross weight, each component concentration of described minor component is: the SiO of 50-200ppm
2, the CaCO of 200-1500ppm
3, the ZrO of 50-500ppm
2, the Nb of 50-500ppm
2O
5, the Na of 50-300ppm
2O.
The contriver finds through lot of experiments, by reasonable control ferrite principal constituent proportioning, especially controls Fe
2O
3, ZnO and NiO content, and be equipped with suitable minor component, can obtain a kind ofly under normal temperature, high temperature, all will have high incremental permeability μ
ΔThe high DC stacked soft magnetic ferrite of wide temperature.
In the above-mentioned principal constituent scope, if Fe
2O
3Content then can not get desirable high saturation magnetic flux density less than 53.2mol%; If Fe
2O
3Content is greater than 56.1mol%, and then the resistivity of material sharply descends, specific loss increases.If ZnO content is less than 2.5mol%, then magnetic permeability descends to some extent; If ZnO content is greater than 10.5mol%, then the Curie temperature of material reduces.If NiO content is greater than 5mol%, then magnetic permeability descends, and loss increases.
Above-mentioned minor component mainly is to form resistive formation at the ferrite crystal boundary, and crystal grain thinning promotes the uniform crystal particles growth, to reduce spillage of material.When their content is lower than lower value, do not have the effect that reduces spillage of material; And when their content is higher than above-mentioned higher limit, then cause easily crystal grain misgrowth, make the mis-behave of material.
The preparation method of the high DC stacked soft magnetic ferrite of a kind of wide temperature, described preparation method's concrete steps are as follows:
(1) principal constituent is carried out wet mixing, then 750-1000 ℃ lower pre-burning 0.5-5 hour the presintering thing;
(2) add minor component in the presintering thing, the wet type sand milling obtains ferrite slurry;
(3) add the PVA binding agent in the ferrite slurry, carry out mist projection granulating, then compression moulding, formed body under the condition of control oxygen partial pressure in 1300～1350 ℃, sintering 4～10 hours, after the cooling finished product.By improving technique, in order to reduce the shrinking percentage of material, reduce blank cracking, distortion.
As preferably, by accounting for principal constituent and minor component gross weight, described PVA consumption of binder is 0.05-1.5%.
As preferably, oxygen partial pressure concentration is controlled to be below 0.5%.
As preferably, wherein formed body is 5 ℃～8 ℃/minute at 1100 ℃ to 1300～1350 ℃ temperature rise period temperature rise rate, and oxygen partial pressure concentration is controlled to be below 0.5%.In order to reduce the shrinking percentage of material, reduce blank cracking, distortion.
The invention has the beneficial effects as follows: under normal temperature, high temperature, all will have high incremental permeability μ
Δ, under the DC stacked magnetic field of 100A/m, the incremental permeability μ under 25 ℃
ΔMore than 600, the incremental permeability μ under 100 ℃
ΔMore than 300.
Embodiment
Below by specific embodiment, technical scheme of the present invention is described in further detail.
Among the present invention, if not refer in particular to, the raw material that adopts and equipment etc. all can be buied from market or this area is commonly used.Method among the following embodiment if no special instructions, is the ordinary method of this area.
Manufacture craft of the present invention is:
(1) principal constituent is carried out wet mixing, then 750-1000 ℃ lower pre-burning 0.5-5 hour the presintering thing;
(2) add minor component in the presintering thing, the wet type sand milling obtains ferrite slurry;
(3) in ferrite slurry, add by accounting for principal constituent and minor component gross weight 0.05-1.5%PVA binding agent, carry out mist projection granulating, then compression moulding, formed body control oxygen partial pressure below 0.5% in 1300～1350 ℃, sintering 4～10 hours gets finished product after the cooling.Wherein formed body is 5 ℃～8 ℃/minute at 1100 ℃ to 1300～1350 ℃ temperature rise period temperature rise rate, and oxygen partial pressure concentration is controlled to be below 0.5%.
Embodiment 1
Take by weighing Fe with the main component content shown in the table 1
2O
3, MnO, ZnO, NiO starting material carry out wet mixing, then 900 ℃ of lower pre-burnings are 2 hours.According to the gross weight of main composition, add the SiO of 150ppm in the mixture after the pre-burning
2, 900ppm CaCO
3, 200ppm ZrO
2, 200ppm Nb
2O
5Na with 100ppm
2O, wherein Na
2O adds with NaCl, and the wet type sand milling obtains ferrite slurry.In ferrite slurry, add by the PVA binding agent that accounts for principal constituent and minor component gross weight 1wt%, carry out mist projection granulating.Powder after the granulation is shaped to the standard annular ferrite core of test usefulness.Formed body in control oxygen partial pressure 0.1% in 1330 ℃ of sintering 5 hours, be 5 ℃/minute at 1100 ℃～1330 ℃ temperature rise period temperature rise rate wherein, oxygen partial pressure concentration is 0.1%.Cooling stages is at balance O
2-N
2Atmosphere under carry out.By the xrf analysis instrument, whether the final composition that detects ferrite core forms consistent with design.
Measure the initial permeability μ i of ferrite core with HP4284 inductance/electric impedance analyzer, and under the DC stacked magnetic field of 100A/m, measure the incremental permeability μ of ferrite core
Δ
As seen from Table 1, main component content within the scope of the present invention, ferrite core incremental permeability under normal temperature, high temperature is high.Incremental permeability under 25 ℃ is more than 600, and the incremental permeability under 100 ℃ is more than 300.When main component content not within the scope of the present invention, then can make the normal temperature incremental permeability have downtrending (see test 107,108) or high temperature incremental permeability that downtrending (seeing test 106,109) is arranged.
Table 1:
Embodiment 2
The preparation technology of present embodiment is identical with embodiment 1.Be Fe in the principal constituent
2O
3, MnO, ZnO, NiO content be fixed as the Fe of 53.9mol%
2O
3, the ZnO of MnO, 7mol% of 37.9mol% and the NiO of 1.2mol%.According to the total weight of main composition, the add-on of minor component is as shown in table 2.Na wherein
2O is with Na
2CO
3Form add.
As can be seen from Table 2, when the content of minor component within the scope of the present invention, ferrite core normal temperature, high temperature incremental permeability are high.When the content of minor component departs from the scope of the invention (test number 203,206,209,212), the normal temperature of ferrite core, high temperature incremental permeability have a declining tendency.
Table 2:
Embodiment 3
The composition of present embodiment is identical with table 1 test number 103, and preparation technology is identical with embodiment 1.Just as shown in table 3 in temperature rise rate and the oxygen partial pressure concentration of 1100 ℃～1330 ℃ sections that heat up.
As can be seen from Table 3, when temperature rise rate and the oxygen partial pressure deviation of concentration scope of the invention, the normal temperature of ferrite core, high temperature incremental permeability have a declining tendency.
Table 3:
Embodiment 4
The composition of present embodiment is identical with table 1 test number 103, and preparation technology is identical with embodiment 1.Just step (3) sintering temperature and sintering time are as shown in table 4.
As can be seen from Table 4, when sintering temperature and sintering time departed from the scope of the invention, the normal temperature of ferrite core, high temperature incremental permeability had a declining tendency.
Table 4:
Above-described embodiment is a kind of better scheme of the present invention, is not that the present invention is done any pro forma restriction, also has other variant and remodeling under the prerequisite that does not exceed the technical scheme that claim puts down in writing.
Claims (5)
1. high DC stacked soft magnetic ferrite of wide temperature, it is characterized in that: the high DC stacked soft magnetic ferrite of described wide temperature is comprised of principal constituent and minor component, and the molar percentage of each component of described principal constituent is: Fe
2O
353.2-56.1mol%, ZnO 2.5-10.5mol%, NiO≤5mol%, MnO surplus; By accounting for the principal constituent gross weight, each component concentration of described minor component is: the SiO of 50-200ppm
2, the CaCO of 200-1500ppm
3, the ZrO of 50-500ppm
2, the Nb of 50-500ppm
2O
5, the Na of 50-300ppm
2O.
2. the preparation method of the high DC stacked soft magnetic ferrite of wide temperature as claimed in claim 1, it is characterized in that: described preparation method's concrete steps are as follows:
(1) principal constituent is carried out wet mixing, then 750-1000 ℃ lower pre-burning 0.5-5 hour the presintering thing;
(2) add minor component in the presintering thing, the wet type sand milling obtains ferrite slurry;
(3) add the PVA binding agent in the ferrite slurry, carry out mist projection granulating, then compression moulding, formed body under the condition of control oxygen partial pressure in 1300～1350 ℃, sintering 4～10 hours, after the cooling finished product.
3. the preparation method of the high DC stacked soft magnetic ferrite of wide temperature according to claim 2, it is characterized in that: by accounting for principal constituent and minor component gross weight, described PVA consumption of binder is 0.05-1.5%.
4. according to claim 2 or the preparation method of the high DC stacked soft magnetic ferrite of 3 described wide temperature, it is characterized in that: oxygen partial pressure concentration is controlled to be below 0.5%.
5. according to claim 2 or the high DC stacked soft magnetic ferrite of 3 described wide temperature, it is characterized in that: wherein formed body is 5 ℃～8 ℃/minute at 1100 ℃ to 1300～1350 ℃ temperature rise period temperature rise rate, and oxygen partial pressure concentration is controlled to be below 0.5%.
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| Application Number | Priority Date | Filing Date | Title |
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|---|---|---|---|
| CN2012103859997A CN102964116A (en) | 2012-10-12 | 2012-10-12 | Wide-temperature range high DC superimposed soft magnetic ferrite |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107540360A (en) * | 2016-06-25 | 2018-01-05 | 临沂春光磁业有限公司 | It is a kind of that there is high saturated magnetic induction, high DC stacked Ferrite Material |
| EP3288044A4 (en) * | 2015-04-22 | 2018-10-31 | Hengdian Group DMEGC Magnetics Co. Ltd. | Soft-magnetic mnzn system power ferrite |
| CN113480302A (en) * | 2021-09-03 | 2021-10-08 | 天通控股股份有限公司 | Wide-temperature-range high-permeability manganese-zinc soft magnetic ferrite for automotive electronics and preparation method thereof |
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| CN1397961A (en) * | 2001-07-19 | 2003-02-19 | 清华同方股份有限公司 | Components and preparing process of VHF plate sensor material |
| CN102054552A (en) * | 2010-08-16 | 2011-05-11 | 横店集团东磁股份有限公司 | NiMnZn ferrite material and preparation method thereof |
-
2012
- 2012-10-12 CN CN2012103859997A patent/CN102964116A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1397961A (en) * | 2001-07-19 | 2003-02-19 | 清华同方股份有限公司 | Components and preparing process of VHF plate sensor material |
| CN102054552A (en) * | 2010-08-16 | 2011-05-11 | 横店集团东磁股份有限公司 | NiMnZn ferrite material and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 刘九皋 等: "锰锌铁氧体材料技术性能的拓展", 《磁性材料及器件》, vol. 36, no. 2, 30 April 2005 (2005-04-30), pages 7 - 12 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3288044A4 (en) * | 2015-04-22 | 2018-10-31 | Hengdian Group DMEGC Magnetics Co. Ltd. | Soft-magnetic mnzn system power ferrite |
| CN107540360A (en) * | 2016-06-25 | 2018-01-05 | 临沂春光磁业有限公司 | It is a kind of that there is high saturated magnetic induction, high DC stacked Ferrite Material |
| CN107540360B (en) * | 2016-06-25 | 2020-12-04 | 临沂春光磁业有限公司 | Ferrite material with high saturation magnetic induction intensity and high direct current superposition |
| CN113480302A (en) * | 2021-09-03 | 2021-10-08 | 天通控股股份有限公司 | Wide-temperature-range high-permeability manganese-zinc soft magnetic ferrite for automotive electronics and preparation method thereof |
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Application publication date: 20130313 |