JPH03212906A - Manufacture of high frequency low loss ferrite for power supply - Google Patents
Manufacture of high frequency low loss ferrite for power supplyInfo
- Publication number
- JPH03212906A JPH03212906A JP2008753A JP875390A JPH03212906A JP H03212906 A JPH03212906 A JP H03212906A JP 2008753 A JP2008753 A JP 2008753A JP 875390 A JP875390 A JP 875390A JP H03212906 A JPH03212906 A JP H03212906A
- Authority
- JP
- Japan
- Prior art keywords
- ferrite
- loss
- power supply
- high frequency
- firing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229910000859 α-Fe Inorganic materials 0.000 title claims abstract description 21
- 238000004519 manufacturing process Methods 0.000 title claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000000203 mixture Substances 0.000 claims abstract description 7
- 239000001301 oxygen Substances 0.000 claims abstract description 7
- 239000002131 composite material Substances 0.000 claims abstract description 4
- 238000010304 firing Methods 0.000 claims description 19
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 abstract description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract 2
- GNTDGMZSJNCJKK-UHFFFAOYSA-N divanadium pentaoxide Chemical compound O=[V](=O)O[V](=O)=O GNTDGMZSJNCJKK-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
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 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
- PBCFLUZVCVVTBY-UHFFFAOYSA-N tantalum pentoxide Inorganic materials O=[Ta](=O)O[Ta](=O)=O PBCFLUZVCVVTBY-UHFFFAOYSA-N 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 230000004907 flux Effects 0.000 description 6
- 230000007423 decrease Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- 239000000654 additive Substances 0.000 description 3
- 230000035699 permeability Effects 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 229910052720 vanadium Inorganic materials 0.000 description 2
- KOAWAWHSMVKCON-UHFFFAOYSA-N 6-[difluoro-(6-pyridin-4-yl-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)methyl]quinoline Chemical compound C=1C=C2N=CC=CC2=CC=1C(F)(F)C(N1N=2)=NN=C1C=CC=2C1=CC=NC=C1 KOAWAWHSMVKCON-UHFFFAOYSA-N 0.000 description 1
- 229910019714 Nb2O3 Inorganic materials 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
Landscapes
- Soft Magnetic Materials (AREA)
- Magnetic Ceramics (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、周波数２００ｋ）ｌｚ〜ＩＭＨｚのスイッチ
ング電源等の磁心等に用いるのに適したＭ ｎ −Ｚ
ｎ系低損失フェライト焼結体の製造方法に関するもので
ある。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides an M n -Z magnetic core suitable for use in a magnetic core of a switching power supply with a frequency of 200k to IMHz.
The present invention relates to a method for manufacturing an n-based low-loss ferrite sintered body.
（従来の技術）
Ｍ ｎ −Ｚ ｎ系フェライトは、各種通信機器、民生
用機器等のトランス用材料に用いられている。(Prior Art) Mn-Zn-based ferrites are used as materials for transformers in various communication devices, consumer devices, and the like.
従来のスイッチング電源用トランスにおいては、スイッ
チング周波数として専ら２５〜２００ｋＨｚ程度のもの
が使用されている。このスイッチング電源用トランスに
用いられる低損失フェライトとしては、副成分として、
Ｃａｂ、 Ｓｉｎ、を含む、あるいは、ＣａＯ。In conventional switching power supply transformers, a switching frequency of about 25 to 200 kHz is exclusively used. The low-loss ferrite used in this switching power supply transformer has as a subcomponent:
Contains Cab, Sin, or CaO.
ＶｚＯｓ ＋ ５ｉ０２を含む所望のＭ ｎ −Ｚ ｎ
系フェライトが使用されている。Desired M n −Z n containing VzOs + 5i02
ferrite is used.
（発明が解決しようとする問題点）
近年、スイッチング電源をさらに小型・軽量化するため
、スイッチング周波数は、益々高い周波数領域に設定さ
れる傾向にあり、この目的に合うフェライト材料として
も、高周波において、より損失の少ない材料が必要不可
欠となっている。(Problem to be solved by the invention) In recent years, in order to further reduce the size and weight of switching power supplies, the switching frequency has tended to be set in an increasingly higher frequency range. , materials with lower loss are essential.
しかし、従来のＭ ｎ −Ｚ ｎ系フェライトでは、数
百ｋ Ｈｚ以上の周波数領域では電力損失が増大してし
まう欠点があった。However, the conventional Mn-Zn-based ferrite has the drawback that power loss increases in a frequency range of several hundred kHz or more.
本発明は、数百ｋ）ｌｚｚ以上周波数領域においても、
充分電力損失の少ない電源用高周波低損失フェライトを
提供することを目的とする。The present invention can also be applied in the frequency range of several hundred k)lzz or more.
The purpose of the present invention is to provide a high-frequency, low-loss ferrite for power supplies with sufficiently low power loss.
（問題点を解決するための手段）
本発明は、Ｆａ２Ｏ３，ＭｎＯ，ＺｎＯを主成分とし、
副成分として、ＣａＯ３００〜１５００ｐｐｍ、 Ｓｉ
ｎ、 ２８０〜１１０００ｐｐｍ，更にＶ、 Ｏ，、Ｎ
ｂ、 Ｏ，、Ｔａ、 Ｏ，の少なくとも一種以上を２０
０〜１５００ｐｐ謙複合添加、含有するフェライト組成
物を所定形状に成形し、該成形体を焼成温度１１８０℃
以下、焼成雰囲気は、酸素濃度０．５％以下から成る焼
成条件において焼成するものである。(Means for solving the problems) The present invention uses Fa2O3, MnO, and ZnO as main components,
As subcomponents, CaO300-1500ppm, Si
n, 280-11000ppm, further V, O,,N
b, O,, Ta, O, at least one or more of 20
The ferrite composition containing 0 to 1,500 pp of composite additives is molded into a predetermined shape, and the molded body is fired at a temperature of 1,180°C.
Hereinafter, the firing atmosphere is one in which the firing conditions are such that the oxygen concentration is 0.5% or less.
本発明により得られるフェライト焼結体は、スイッチン
グ電源用トランス磁心等に用いるのに適しており、とり
わけ、スイッチング周波数２００ｋ）Ｉｚ〜ＩＭＨｚ程
度の高周波領域において、極めて、損失が少なく、その
効力を発揮できる。The ferrite sintered body obtained by the present invention is suitable for use in transformer cores for switching power supplies, etc., and exhibits extremely low loss and exhibits its effectiveness particularly in the high frequency range of switching frequencies of about 200k to IMHz. can.
（実施例）
以下、本発明に関する電源用高周波低損失フェライトの
実施例を説明する。(Example) Hereinafter, an example of a high frequency low loss ferrite for power supply according to the present invention will be described.
Ｆｅ、Ｏ，（５３，５ｍｏ１％） 、 にｎｏ （３
７，５＋ｏ１％） 、 Ｚｎ０（９，Ｏｍｏ１％）
を主成分とする原料をボールミルにて混合後、９００℃
にて仮焼成し、副成分として、ＣａＣ０，を７５０ｐｐ
ｍ （ＣａＯに換算すると４２０ｐｐｍ） ｔＮｂ２０
．を５００ｐｐｍ、 ５ｉ０２を３５０ｐｐＨ１複合添
加し、ボールミルにて１２時間粉砕した。但し、Ｃａｂ
、 ＳｉＯ□のように、予め原料に含有されている副成
分については、仮焼成後に添加する量をその分だけ減じ
、全体として上記成分の割合に一致する様にした。Fe, O, (53.5mol1%), nino (3
7,5+o1%), Zn0(9,Omo1%)
After mixing the raw materials mainly composed of in a ball mill,
750pp of CaC0 as a subcomponent.
m (420 ppm when converted to CaO) tNb20
．． A combination of 500 ppm and 350 pph of 5i02 was added, and the mixture was ground in a ball mill for 12 hours. However, Cab
, SiO□, and other subcomponents previously contained in the raw materials, the amount added after pre-firing was reduced by that amount, so that the overall proportions matched the above-mentioned component proportions.
この粉砕原料を乾燥後、バインダーを１．（ｈｔ％添加
し、造粒・成形した。この成形体を焼成温度１１５０℃
、焼成雰囲気は酸素濃度０．０５％にて５時間焼成した
。なお、焼成体の形状は、外径２５ｍｍ、内径１５ｍ＋
、高さ７．５閣のリング状とした。After drying this pulverized raw material, 1. (ht% was added, granulated and molded. This molded body was fired at a temperature of 1150°C.
The firing was carried out for 5 hours in an oxygen concentration of 0.05%. The shape of the fired body is 25 mm in outer diameter and 15 m+ in inner diameter.
, in the form of a ring with a height of 7.5 towers.
この実施例１と同様の試料作製工程において、添加物系
及び焼成条件（焼成温度・焼成雰囲気）を変えて各試料
を作製した。この結果を第１表に示す。In the same sample preparation process as in Example 1, each sample was prepared by changing the additive system and firing conditions (firing temperature and firing atmosphere). The results are shown in Table 1.
試料１，２，４．７〜１４．１６〜１９は、本発明の実
施例である。なお、試料３，５，６．１５は、焼成条件
（焼成温度・焼成雰囲気）が特許請求範囲外の比較例で
あり、試料２０は、添加物として、 Ｃａｂ、 Ｖ２Ｏ
３，Ｓｉｎ、を含有する従来材の例である。Samples 1, 2, 4.7-14.16-19 are examples of the present invention. Note that Samples 3, 5, and 6.15 are comparative examples in which the firing conditions (firing temperature and firing atmosphere) are outside the scope of the claims, and Sample 20 contains Cab, V2O as additives.
This is an example of a conventional material containing 3,Sin.
実施例１の電力損失の温度特性を第１図に、また、電力
損失の周波数特性を第２図に示した。なお、比較として
従来例の電力損失の温度特性及び周波数特性も第１図及
び第２図に示した。The temperature characteristics of power loss in Example 1 are shown in FIG. 1, and the frequency characteristics of power loss are shown in FIG. For comparison, the temperature characteristics and frequency characteristics of the power loss of the conventional example are also shown in FIGS. 1 and 2.
第１図より、実施例１の電源用高周波低損失フェライト
は、周波数ｆ ＝５００ｋＨｚ、磁束密度Ｂ＋ａ＝５０
ｍＴにおいて、２０℃〜１２０℃の広温度範囲で電力損
失が従来材の１７２〜１／３程度と、極めて低いことが
わかる。From FIG. 1, the high-frequency low-loss ferrite for power supply of Example 1 has a frequency f = 500 kHz and a magnetic flux density B+a = 50.
It can be seen that at mT, the power loss is extremely low at about 172 to 1/3 of that of conventional materials over a wide temperature range of 20°C to 120°C.
また、第２図より、実施例１の電源用高周波低損失フェ
ライトが、従来の電源用フェライトに比べ、損失が１７
２となるのは、磁束密度５０ｍＴでは２００ｋＨｚ以上
、１００ｍＴでは、３００ｋＨｚ以上であり、２００ｍ
Ｔでは、ＩＭＨｚ以上であることが予想される。すなわ
ち、実施例１が高周波低損失という特徴を発揮するのは
、周波数２００ｋＨｚ以上、磁束密度１００ｍＴ以下の
動作条件であると言える。Moreover, from FIG. 2, the high frequency low loss ferrite for power supply of Example 1 has a loss of 17% compared to the conventional ferrite for power supply.
2 is 200kHz or more when the magnetic flux density is 50mT, 300kHz or more when the magnetic flux density is 100mT, and 200mT.
At T, it is expected to be above IMHz. That is, it can be said that Example 1 exhibits the characteristic of low loss at high frequencies under the operating conditions of a frequency of 200 kHz or more and a magnetic flux density of 100 mT or less.
また、実施例１以外の本発明の電源用高周波低損失フェ
ライトにおいても、第２図に示したものと同様の傾向が
見られた。Furthermore, the same tendency as shown in FIG. 2 was observed in the high-frequency low-loss ferrites for power supplies of the present invention other than Example 1.
なお、主成分である、Ｆｅ２Ｏ３，ＭｎＯ，ＺｎＯの割
合は、Ｆｅ、０．５２．０〜５５．０ｍｏ１％、 Ｍｎ
０３１．０〜４２．０＋ｍｏ１％。In addition, the proportions of Fe2O3, MnO, and ZnO, which are the main components, are Fe, 0.52.0 to 55.0 mo1%, Mn
031.0-42.0+mo1%.
Ｚｎ０６．０〜１６．０ｍｏ１％の範囲であれば良い。It is sufficient if the Zn content is in the range of 06.0 to 16.0 mo1%.
以上の如く、焼成温度が１１８０℃より高いと、あるい
は、酸素濃度が０．５％より高いと、異常結晶粒が出始
め、損失が増大すると共に、透磁率及びＱも低下する。As described above, when the firing temperature is higher than 1180° C. or the oxygen concentration is higher than 0.5%, abnormal crystal grains begin to appear, the loss increases, and the magnetic permeability and Q also decrease.
従って、本発明は、焼成温度１１８０℃以下、焼成雰囲
気は、酸素濃度０．５％以下で焼成するものである。Therefore, in the present invention, firing is performed at a firing temperature of 1180° C. or lower and a firing atmosphere with an oxygen concentration of 0.5% or lower.
また、本発明において、副成分の添加量を限定した理由
は、以下のとおりである。Further, in the present invention, the reason why the amount of the subcomponents added is limited is as follows.
副成分のＣａＯが１５００ｐｐｍより多いと、電力損失
が増大すると共に、透磁率が急激に低下する。また。If the subcomponent CaO is more than 1500 ppm, power loss increases and magnetic permeability rapidly decreases. Also.
ＣａＯが３００ｐｐｍよりも少ないと、電気抵抗が低下
するため、高周波領域における渦電流損失が増大し、電
力損失は大きくなる。When CaO is less than 300 ppm, electrical resistance decreases, resulting in increased eddy current loss in the high frequency region and increased power loss.
副成分のＶｚ Ｏｓ −Ｎｂｉ Ｏｓ ＋丁ａ２０．及
びＳｉｎ、が本発明の範囲以上になると、異常焼結し、
損失が増大すると共に、透磁率及びＱも低下する。Subcomponent Vz Os −Nbi Os + 20. and Sin exceeds the range of the present invention, abnormal sintering occurs,
As losses increase, permeability and Q also decrease.
また、副成分のＶ、ＯＳ、 Ｎｂ２Ｏ３，Ｔａ、Ｏ，及
びＳｉｎ、が本発明の範囲未満になると、電気抵抗が低
下し、損失は増大する。Furthermore, when the subcomponents V, OS, Nb2O3, Ta, O, and Sin fall below the range of the present invention, the electrical resistance decreases and the loss increases.
（発明の効果）
前述の如く、本発明の電源用高周波低損失フェライトは
、Ｆｅ、 ０． 、 ＭｎＯ、ＺｎＯを主成分とし、副
成分として、Ｃａ０３００〜１５００ｐｐｍ、 ｓｉｏ
、 ２８０〜１１０００ｐｐに、更にｖｚｏ＠ ＨＮｂ
ｔｏＳ ｇ ｒａｚｏｇの少なくとも一種を２００〜１
５００ｐｐ園複合添加、含有するフェライト組成物を所
定形状に成形し、該成形体を焼成温度１１８０℃以下、
焼成雰囲気は、酸素濃度０．５％以下から成る焼成条件
にて焼成することにより、数百ｋ）Ｉｚ以上の高周波領
域において、電力損失を著しく低減できるものである。(Effects of the Invention) As described above, the high frequency low loss ferrite for power supply of the present invention is made of Fe, 0. , MnO, ZnO as main components, Ca0300~1500ppm as subcomponents, sio
, 280-11000pp, and further vzo@HNb
at least one type of toS grazog 200-1
The ferrite composition containing 500 pp of composite addition was molded into a predetermined shape, and the molded body was fired at a temperature of 1180° C. or lower.
By firing in a firing atmosphere with an oxygen concentration of 0.5% or less, power loss can be significantly reduced in a high frequency region of several hundred k) Iz or more.
第１図は、本発明に係る実施例１の場合の周波数５００
ｋＨｚ、磁束密度５０ｍＴにおける電力損失の温度特性
を従来例の場合と比較して示したものであり、第２図は
、磁束密度５０・１００・２００ｍＴ 、温度８０℃に
おける本発明に係る実施例１の電力損失の周波数特性を
従来例の場合と比較して示したものである。
第１図
度
（℃）
１２図
頷
１００ ２ＣＸ）
５ｏＯ１ｏＯＯ
周波数
（ｋＨｚ）FIG. 1 shows a frequency of 500 in the case of Example 1 according to the present invention.
The temperature characteristics of power loss at kHz and magnetic flux density of 50 mT are shown in comparison with those of the conventional example. Fig. 2 shows Example 1 according to the present invention at magnetic flux density of 50, 100, and 200 mT and temperature of 80°C. This figure shows the frequency characteristics of power loss compared with that of the conventional example. 1st degree (°C) 12th nod 100 2CX) 5oO1oOO Frequency (kHz)
Claims (1)
分として、ＣａＯ ３００〜１５００ｐｐｍ、ＳｉＯ＿
２ ２８０〜１０００ｐｐｍ，更にＶ＿２Ｏ＿５，Ｎｂ
＿２Ｏ＿５，Ｔａ＿２Ｏ＿５の少なくとも一種を２００
〜１５００ｐｐｍ複合添加、含有するフェライト組成物
を所定形状に成形し、該成形体を焼成温度１１８０℃以
下、焼成雰囲気は、酸素濃度０．５％以下から成る焼成
条件において焼成したことを特徴とする電源用高周波低
損失フェライトの製造方法。The main components are Fe_2O_3, MnO, and ZnO, and the subcomponents are CaO 300 to 1500 ppm, SiO_
2 280-1000ppm, further V_2O_5, Nb
At least one of _2O_5 and Ta_2O_5 at 200%
A ferrite composition containing ~1500 ppm composite addition was molded into a predetermined shape, and the molded body was fired under firing conditions consisting of a firing temperature of 1180° C. or lower and a firing atmosphere containing an oxygen concentration of 0.5% or lower. A method for producing high frequency low loss ferrite for power supplies.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008753A JP2556917B2 (en) | 1990-01-18 | 1990-01-18 | Manufacturing method of high frequency and low loss ferrite for power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008753A JP2556917B2 (en) | 1990-01-18 | 1990-01-18 | Manufacturing method of high frequency and low loss ferrite for power supply |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03212906A true JPH03212906A (en) | 1991-09-18 |
| JP2556917B2 JP2556917B2 (en) | 1996-11-27 |
Family
ID=11701688
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2008753A Expired - Lifetime JP2556917B2 (en) | 1990-01-18 | 1990-01-18 | Manufacturing method of high frequency and low loss ferrite for power supply |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2556917B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04154624A (en) * | 1990-10-16 | 1992-05-27 | Alps Electric Co Ltd | Mn-zn ferrite |
| JP2013177289A (en) * | 2012-02-10 | 2013-09-09 | Tdk Corp | Ferrite core and transformer |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101435429B1 (en) | 2012-02-10 | 2014-08-29 | 티디케이가부시기가이샤 | Ferrite core and transformer |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS494196A (en) * | 1972-05-02 | 1974-01-14 | ||
| JPS58114401A (en) * | 1981-12-28 | 1983-07-07 | Tdk Corp | Superlow loss ferrite for power source |
| JPS60132301A (en) * | 1983-12-20 | 1985-07-15 | Sumitomo Special Metals Co Ltd | Oxide magnetic material |
| JPS60262405A (en) * | 1984-06-11 | 1985-12-25 | Sumitomo Special Metals Co Ltd | Manufacture of mn-zn ferrite |
| JPS61252606A (en) * | 1985-05-01 | 1986-11-10 | Tohoku Metal Ind Ltd | Magnetic material of low-loss oxide |
-
1990
- 1990-01-18 JP JP2008753A patent/JP2556917B2/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS494196A (en) * | 1972-05-02 | 1974-01-14 | ||
| JPS58114401A (en) * | 1981-12-28 | 1983-07-07 | Tdk Corp | Superlow loss ferrite for power source |
| JPS60132301A (en) * | 1983-12-20 | 1985-07-15 | Sumitomo Special Metals Co Ltd | Oxide magnetic material |
| JPS60262405A (en) * | 1984-06-11 | 1985-12-25 | Sumitomo Special Metals Co Ltd | Manufacture of mn-zn ferrite |
| JPS61252606A (en) * | 1985-05-01 | 1986-11-10 | Tohoku Metal Ind Ltd | Magnetic material of low-loss oxide |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04154624A (en) * | 1990-10-16 | 1992-05-27 | Alps Electric Co Ltd | Mn-zn ferrite |
| JP2013177289A (en) * | 2012-02-10 | 2013-09-09 | Tdk Corp | Ferrite core and transformer |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2556917B2 (en) | 1996-11-27 |
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