JPH0778711A - Magnetic core and manufacture thereof - Google Patents
Magnetic core and manufacture thereofInfo
- Publication number
- JPH0778711A JPH0778711A JP16279293A JP16279293A JPH0778711A JP H0778711 A JPH0778711 A JP H0778711A JP 16279293 A JP16279293 A JP 16279293A JP 16279293 A JP16279293 A JP 16279293A JP H0778711 A JPH0778711 A JP H0778711A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- oxide
- metal
- oxide gel
- metal powder
- 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.)
- Pending
Links
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- Compounds Of Iron (AREA)
- Soft Magnetic Materials (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、トランス・ノイズフィ
ルタ・平滑チョーク等に用いる磁心材料に関し、特にス
ィッチング電源等のパワーエレクトロニクス機器に用い
る、高周波において透磁率及び飽和磁束密度が大きく損
失が小さい磁心材料に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic core material used for transformers, noise filters, smooth chokes, etc., and particularly for use in power electronic equipment such as switching power supplies, which has large permeability and saturation magnetic flux density and small loss at high frequencies. Regarding materials.
【０００２】[0002]
【従来の技術】従来、スイッチング電源等に用いる高周
波用磁心材料としては、電気抵抗が大きいために渦電流
損失が小さく、高周波における透磁率の低下が小さいと
いう理由から、フェライトを用いたものが多く使われて
きた。ところがフェライト材料は酸化物のフェリ磁性体
であるため、飽和磁束密度の面では満足できるものでは
なかった。2. Description of the Related Art Conventionally, as a high frequency magnetic core material used for a switching power supply or the like, ferrite is often used because it has a large electric resistance and thus a small eddy current loss and a small decrease in magnetic permeability at a high frequency. Has been used. However, since the ferrite material is an oxide ferrimagnetic material, it is not satisfactory in terms of saturation magnetic flux density.
【０００３】一方硅素鋼・センダスト等に代表される磁
性金属材料は、飽和磁束密度の点ではフェライト材料の
２倍以上の値をもつ。ところがこれらの材料は電気抵抗
がフェライト材料に比べると極端に小さく、高周波領域
での使用に耐え得るものではなかった。磁性金属材料の
高飽和磁束密度という特長を生かし、電気抵抗を大きく
しようとするものにたとえば特開平０４−２１７３９号
公報または特開平０５−３６５１４号公報等に示されて
いるような技術が知られている。On the other hand, a magnetic metal material typified by silicon steel, sendust, etc. has a value of more than twice that of a ferrite material in terms of saturation magnetic flux density. However, the electric resistance of these materials is extremely smaller than that of ferrite materials, and they cannot withstand use in a high frequency region. Techniques such as those disclosed in Japanese Patent Application Laid-Open No. 04-21739 or Japanese Patent Application Laid-Open No. 05-36514 are known for attempting to increase electric resistance by taking advantage of the high saturation magnetic flux density of magnetic metal materials. ing.
【０００４】前記従来技術では、センダスト（ＦｅＳｉ
Ａｌ合金）粉末の表面を電気的絶縁の役割をもつ薄膜層
で覆い、この複合材料を圧縮成形することにより、フェ
ライト材料の高電気抵抗と磁性金属材料の高飽和磁束密
度を達成しようとするものである。さらに前記従来技術
では、絶縁膜としてフェライトを用いることにより、成
形体の実効透磁率も大きくできることも述べられてい
る。In the above-mentioned prior art, sendust (FeSi
(Al alloy) The surface of the powder is covered with a thin film layer having the role of electrical insulation, and the composite material is compression-molded to achieve high electric resistance of the ferrite material and high saturation magnetic flux density of the magnetic metal material. Is. Further, in the above-mentioned prior art, it is also stated that the effective magnetic permeability of the molded body can be increased by using ferrite as the insulating film.
【０００５】[0005]
【発明が解決しようとする課題】ところが前記の金属／
絶縁膜複合粉末を圧縮成形する際には、母相の金属に比
べて絶縁膜が非常に固くかつ脆いこと、また金属の変形
により複合粉末の表面積が拡大すること等の理由により
前記絶縁膜の破壊が生じ、金属粉末同士が接触するため
電気抵抗が小さくなってしまい、期待した効果が得られ
ないという問題があった。However, the above-mentioned metal /
When the insulating film composite powder is compression-molded, the insulating film is very hard and brittle as compared with the metal of the matrix phase, and the surface area of the composite powder is expanded due to the deformation of the metal. There is a problem in that the expected effect cannot be obtained because the metal powders are broken and the metal powders are brought into contact with each other to reduce the electric resistance.
【０００６】さらに金属粉末が変形する際に、格子歪が
生じ、磁歪の影響で磁気特性が損なわれるという問題も
有していた。本発明はこのような問題に鑑みてなされた
ものであり、圧縮成形を行なうことなく、高密度の磁心
を得ることを技術的課題とする。Further, when the metal powder is deformed, lattice distortion occurs, and there is a problem that magnetic characteristics are impaired by the influence of magnetostriction. The present invention has been made in view of such a problem, and an object thereof is to obtain a high-density magnetic core without performing compression molding.
【０００７】[0007]
【課題を解決するための手段】前記課題を解決するため
に、本発明者は、磁性金属粉末を磁性酸化物金属の酸化
物ゲル中に分散させて得られた磁性金属粉末／酸化物ゲ
ル複合体を乾燥後、熱処理してこれを磁心とした。In order to solve the above-mentioned problems, the present inventor has made a magnetic metal powder / oxide gel composite obtained by dispersing magnetic metal powder in an oxide gel of a magnetic oxide metal. After the body was dried, it was heat treated to obtain a magnetic core.
【０００８】[0008]
【発明の具体的な説明】本発明の磁性金属粉末として
は、軟磁性・高飽和磁束密度の磁性金属であれば特に制
限はなく、例えば、純Ｆｅ，Ｆｅ−Ｓｉ系，Ｆｅ−Ａｌ
系，Ｆｅ−Ｓｉ−Ａｌ系，Ｎｉ−Ｆｅ系等の結晶質磁性
金属粉末、あるいはＦｅ−Ｂ−Ｓｉ系，Ｆｅ−Ｂ−Ｓｉ
−Ｃ系，Ｆｅ−Ｂ−Ｓｉ−Ｃｒ系，Ｆｅ−Ｃｏ−Ｂ−Ｓ
ｉ系，Ｆｅ−Ｎｉ−Ｍｏ−Ｂ系 等の非晶質磁性金属粉
末、あるいは最終的には結晶化熱処理により微結晶を析
出させて使用するＦｅ−Ａｌ−Ｓｉ−Ｎｂ−Ｂ系，Ｆｅ
−Ｃｕ−Ｎｂ−Ｓｉ−Ｂ系，Ｆｅ−Ｚｒ−Ｂ系，Ｆｅ−
Ｔａ−Ｃ系，Ｆｅ−Ｔａ−Ｎ系，Ｆｅ−Ｎｂ−Ｂ系等の
非晶質磁性金属粉末を用いることができる。DETAILED DESCRIPTION OF THE INVENTION The magnetic metal powder of the present invention is not particularly limited as long as it is a soft magnetic high saturation magnetic flux density magnetic metal, for example, pure Fe, Fe-Si system, Fe-Al.
System, Fe-Si-Al system, Ni-Fe system, etc. crystalline magnetic metal powder, or Fe-B-Si system, Fe-B-Si system
-C system, Fe-B-Si-Cr system, Fe-Co-BS
i-based, Fe-Ni-Mo-B-based amorphous magnetic metal powder, or finally Fe-Al-Si-Nb-B-based, Fe used by precipitating fine crystals by crystallization heat treatment
-Cu-Nb-Si-B system, Fe-Zr-B system, Fe-
Amorphous magnetic metal powders such as Ta-C type, Fe-Ta-N type and Fe-Nb-B type can be used.
【０００９】またこれらの磁性金属粉末は以下の方法に
よって製造することができる。第１の方法は前記成分の
金属溶湯から直接金属粉末を得る方法である。この場合
の製造方法としては、水アトマイズ法，ガスアトマイズ
法，スプレー法，キャビテーション法，スパークエロー
ジョン法，回転液中射出法 等がある。These magnetic metal powders can be manufactured by the following method. The first method is a method of directly obtaining a metal powder from the molten metal of the above components. As the manufacturing method in this case, there are a water atomizing method, a gas atomizing method, a spray method, a cavitation method, a spark erosion method, a rotating liquid injection method and the like.
【００１０】第２の方法は前記成分の金属バルクあるい
は金属薄帯あるいは金属フレークあるいは金属線 等を
粉砕する方法である。この場合の粉砕は、媒体撹拌型ミ
ル，振動ミル，ローラーミル，ジェットミル等により行
うことができる。第３の方法は前記成分の金属酸化物粉
末をその金属の融点以下の温度で還元して得る方法であ
る。The second method is a method of crushing the metal bulk, metal ribbon, metal flakes, metal wire, etc. of the above components. The pulverization in this case can be carried out by a medium stirring type mill, a vibration mill, a roller mill, a jet mill or the like. The third method is a method in which the metal oxide powder of the above component is reduced at a temperature not higher than the melting point of the metal.
【００１１】この場合の還元剤としては、Ｃ，Ｎａ，Ｍ
ｇ等の固体還元剤あるいはＨ2，ＣＯ，石炭ガス，天然
ガス 等のガス還元剤が使用される。この他に、熱解離
法（カーボニール法），電解法等によっても製造するこ
とができる。前記の方法で得られる磁性金属粉末におい
ては、空気中に安定して取り出すことを目的として粉末
表面に皮膜を形成してもよい。磁性金属粉末／磁性酸化
物複合体の磁気特性の点から、この皮膜は磁性体である
ことが好ましい。As the reducing agent in this case, C, Na, M
A solid reducing agent such as g or a gas reducing agent such as H 2 , CO, coal gas or natural gas is used. In addition to this, it can be manufactured by a thermal dissociation method (carbonyl method), an electrolytic method, or the like. In the magnetic metal powder obtained by the above method, a film may be formed on the surface of the powder for the purpose of stable extraction in the air. From the viewpoint of the magnetic properties of the magnetic metal powder / magnetic oxide composite, this coating is preferably a magnetic material.
【００１２】本発明の磁性酸化物としては、ＭＦｅ2Ｏ4
（ＭはＮｉ，Ｚｎ，Ｃｕ，Ｍｎ，Ｍｇ，Ｆｅ，Ｃｏ，Ｌ
ｉの中の少なくとも１種以上）で表されるスピネル型フ
ェライト、ＭＦｅ12Ｏ19（ＭはＢａ，Ｐｂ，Ｓｒ，Ｃ
ａ，Ｎｉ，Ｌａ，Ａｇの中の少なくとも１種以上）で表
される六方晶フェライト、γ−Ｆｅ2Ｏ3、ＣｒＯ2等の
酸化物を例示することができる。磁性金属粉末／磁性酸
化物複合体の磁心としての磁気特性を向上するために
は、特にＮｉ−Ｚｎフェライト、Ｎｉ−Ｃｕ−Ｚｎフェ
ライト、Ｍｎ−Ｚｎフェライト、Ｍｇ−Ｃｕ−Ｚｎフェ
ライト、Ｍｎ−Ｍｇフェライト等のスピネル型ソフトフ
ェライトであることが好ましい。The magnetic oxide of the present invention includes MFe 2 O 4
(M is Ni, Zn, Cu, Mn, Mg, Fe, Co, L
i) at least one kind of spinel type ferrite, MFe 12 O 19 (M is Ba, Pb, Sr, C
Examples include oxides of hexagonal ferrite, γ-Fe 2 O 3 , and CrO 2 represented by at least one of a, Ni, La, and Ag). In order to improve the magnetic properties of the magnetic metal powder / magnetic oxide composite as a magnetic core, Ni-Zn ferrite, Ni-Cu-Zn ferrite, Mn-Zn ferrite, Mg-Cu-Zn ferrite, Mn-Mg are particularly preferable. It is preferably spinel type soft ferrite such as ferrite.
【００１３】磁性酸化物金属の酸化物ゲルは通常以下の
方法で調製することができる。第１の方法は、磁性酸化
物金属のアルコキシドをアルコール，フェノール等の水
酸基を有する化合物あるいはカルボン酸エステルやその
誘導体あるいはβ−ジケトンあるいはケト酸エステルと
いった有機溶媒に溶解し、これに水を加えて加水分解重
縮合反応を起こさせる方法である。金属に付加するアル
コキシ基としてはメトキシ基，エトキシ基，プロポキシ
基等が例示できる。The oxide gel of the magnetic oxide metal can be usually prepared by the following method. The first method is to dissolve an alkoxide of a magnetic oxide metal in an organic solvent such as a compound having a hydroxyl group such as alcohol or phenol, a carboxylic acid ester or a derivative thereof, a β-diketone or a keto acid ester, and add water to the solution. This is a method of causing a hydrolysis polycondensation reaction. Examples of the alkoxy group added to the metal include a methoxy group, an ethoxy group and a propoxy group.
【００１４】第２の方法は、磁性酸化物金属をアルコー
ル，フェノール等の水酸基を有する化合物溶液中に入
れ、磁性酸化物金属のアルコキシドを合成し、これに水
を加えて加水分解重縮合反応を起こさせる方法である。
アルコキシド合成の際の反応促進剤としてヨウ素や塩化
水銀（II）等を加えることもできる。第３の方法は、磁
性酸化物金属のハロゲン化物をアルコール，フェノール
等の水酸基を有する化合物あるいはエチレンオキシドや
プロピレンオキシド等のエポキシ化合物溶液中に入れ、
磁性酸化物金属のアルコキシドを合成し、これに水を加
えて加水分解重縮合反応を起こさせる方法である。ハロ
ゲン化物としては、塩化物，硝酸化物 等を例示でき
る。またアルコシキド合成の際に副反応を防ぐために、
アンモニア，脂肪族アミン，アルカリ金属アルコキシド
等の塩基を用いても良い。The second method is to put a magnetic oxide metal in a solution of a compound having a hydroxyl group such as alcohol or phenol to synthesize an alkoxide of the magnetic oxide metal, and add water to the alkoxide to carry out a hydrolysis polycondensation reaction. It is a method to wake it up.
Iodine, mercury (II) chloride, etc. can be added as a reaction accelerator in the alkoxide synthesis. A third method is to put a halide of a magnetic oxide metal in a compound having a hydroxyl group such as alcohol or phenol or an epoxy compound solution such as ethylene oxide or propylene oxide,
This is a method in which an alkoxide of a magnetic oxide metal is synthesized, and water is added to the alkoxide to cause a hydrolysis polycondensation reaction. Examples of halides include chloride and nitric oxide. In addition, in order to prevent side reactions during the alkoxide synthesis,
A base such as ammonia, an aliphatic amine or an alkali metal alkoxide may be used.
【００１５】第４の方法は、磁性酸化物金属の酸化物お
よび／または水酸化物をアルコール，フェノール等の水
酸基を有する化合物溶液中に入れ、磁性酸化物金属のア
ルコキシドを合成し、これに水を加えて加水分解重縮合
反応を起こさせる方法である。前記第１〜第４の方法等
によって得られる磁性酸化物金属の酸化物ゲル中に磁性
金属粉末を分散し、この磁性金属／酸化物ゲル複合体を
所望の磁心形状（たとえばＥ型またはＩ型形状）をした
金型に入れ乾燥させる。この際ゲルの体積収縮に起因し
て割れや欠陥が生じやすいので、乾燥はなるべく低温、
たとえば２００℃近傍の温度でゆっくりと行なうことが
好ましい。また、割れや欠陥を防止するために、ホルム
アミド等の乾燥制御剤を用いる、あるいはオートクレー
ブを用いて超臨界乾燥を行なう等の操作を行ってもよ
い。The fourth method is to put an oxide and / or hydroxide of a magnetic oxide metal in a solution of a compound having a hydroxyl group such as alcohol and phenol to synthesize an alkoxide of the magnetic oxide metal, and to add water to this. Is a method of causing a hydrolysis polycondensation reaction. The magnetic metal powder is dispersed in the oxide gel of the magnetic oxide metal obtained by the first to fourth methods, and the magnetic metal / oxide gel composite is formed into a desired magnetic core shape (for example, E-type or I-type). Put it in the shaped mold and let it dry. At this time, since cracks and defects are likely to occur due to the volume contraction of the gel, drying should be performed at a temperature as low as possible.
For example, it is preferable to slowly perform the treatment at a temperature near 200 ° C. Further, in order to prevent cracks and defects, a drying control agent such as formamide may be used, or an operation such as supercritical drying using an autoclave may be performed.
【００１６】得られた磁性金属／磁性酸化物ゲル複合体
中の乾燥酸化物ゲルは多孔質の非晶質体なので、これを
熱処理により焼結し、ゲルを結晶化させ磁心を得る。熱
処理は真空中あるいはアルゴンガスもしくは窒素ガス等
の不活性ガス中あるいは空気等の酸化性ガス中で行な
う。この熱処理条件としては、熱処理温度として２００
〜１５００℃程度、好ましくは３００〜１３００℃程度
である。熱処理時間として０．１〜２０時間程度、好ま
しくは１〜１０時間程度である。なお磁性金属粉末とし
て非晶質材料あるいは微結晶質材料を用いた場合にはこ
れらの材料の結晶化温度以上の温度で熱処理してはなら
ない。Since the dry oxide gel in the obtained magnetic metal / magnetic oxide gel composite is a porous amorphous body, it is sintered by heat treatment to crystallize the gel to obtain a magnetic core. The heat treatment is performed in a vacuum, an inert gas such as argon gas or nitrogen gas, or an oxidizing gas such as air. The heat treatment condition is a heat treatment temperature of 200.
˜1500 ° C., preferably 300 to 1300 ° C. The heat treatment time is about 0.1 to 20 hours, preferably about 1 to 10 hours. When an amorphous material or a microcrystalline material is used as the magnetic metal powder, the heat treatment should not be performed at a temperature higher than the crystallization temperature of these materials.
【００１７】本発明の磁性金属粉末として最終的に微結
晶にして使用する材料を用いた際の結晶化熱処理は、酸
化物ゲルへの混合前あるいは磁性金属／磁性酸化物ゲル
の熱処理後のどちらで行なってもよい。あるいは磁性金
属／磁性酸化物ゲルの熱処理とかねてもよい。熱処理雰
囲気は、真空中あるいはアルゴンガスもしくは窒素ガス
等の不活性ガス中で行う。熱処理条件としては、熱処理
温度として結晶化温度以上、熱処理時間としては、０．
１〜１０時間程度、好ましくは０．５〜５時間程度であ
る。The crystallization heat treatment using the material to be finally microcrystallized as the magnetic metal powder of the present invention may be carried out either before mixing with the oxide gel or after heat treatment of the magnetic metal / magnetic oxide gel. May be done in. Alternatively, the heat treatment may be performed on the magnetic metal / magnetic oxide gel. The heat treatment atmosphere is vacuum or an inert gas such as argon gas or nitrogen gas. As the heat treatment conditions, the heat treatment temperature is equal to or higher than the crystallization temperature, and the heat treatment time is 0.
It is about 1 to 10 hours, preferably about 0.5 to 5 hours.
【００１８】[0018]
【発明の効果】本発明によれば、圧縮成形が不要で、か
つ高周波において磁気特性のきわめて優れた磁心を得る
ことができる。According to the present invention, it is possible to obtain a magnetic core which does not require compression molding and has excellent magnetic characteristics at high frequencies.
Claims (3)
ゲル中に分散させて得られた磁性金属粉末／酸化物ゲル
複合体を乾燥後、熱処理してなる磁心。1. A magnetic core comprising a magnetic metal powder / oxide gel composite obtained by dispersing magnetic metal powder in an oxide gel of a magnetic oxide metal, followed by heat treatment.
ライト、Ｎｉ−Ｃｕ−Ｚｎフェライト、Ｍｎ−Ｚｎフェ
ライト、Ｍｇ−Ｃｕ−Ｚｎフェライト、またはＭｎ−Ｍ
ｇフェライト等のスピネル型ソフトフェライトであるこ
とを特徴とする第１項記載の磁心。2. The magnetic oxide metal is Ni-Zn ferrite, Ni-Cu-Zn ferrite, Mn-Zn ferrite, Mg-Cu-Zn ferrite, or Mn-M.
The magnetic core according to claim 1, which is a spinel type soft ferrite such as g-ferrite.
磁性金属粉末を分散させて磁性金属粉末／酸化物ゲル複
合体を得た後、この磁性金属粉末／酸化物ゲル複合体を
乾燥・熱処理して所定形状の磁心とする磁心の製造方
法。3. A magnetic metal powder / oxide gel composite is obtained by dispersing magnetic metal powder in an oxide gel composed of a magnetic oxide metal, and drying this magnetic metal powder / oxide gel composite. A method of manufacturing a magnetic core by heat-treating to form a magnetic core having a predetermined shape.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16279293A JPH0778711A (en) | 1993-06-30 | 1993-06-30 | Magnetic core and manufacture thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16279293A JPH0778711A (en) | 1993-06-30 | 1993-06-30 | Magnetic core and manufacture thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0778711A true JPH0778711A (en) | 1995-03-20 |
Family
ID=15761299
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16279293A Pending JPH0778711A (en) | 1993-06-30 | 1993-06-30 | Magnetic core and manufacture thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0778711A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006186072A (en) * | 2004-12-27 | 2006-07-13 | Fuji Electric Holdings Co Ltd | Manufacturing method of compound magnetic component |
| CN102513532A (en) * | 2011-12-27 | 2012-06-27 | 安泰科技股份有限公司 | Amorphous powder for diamond tool and manufacture method thereof |
-
1993
- 1993-06-30 JP JP16279293A patent/JPH0778711A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006186072A (en) * | 2004-12-27 | 2006-07-13 | Fuji Electric Holdings Co Ltd | Manufacturing method of compound magnetic component |
| CN102513532A (en) * | 2011-12-27 | 2012-06-27 | 安泰科技股份有限公司 | Amorphous powder for diamond tool and manufacture method thereof |
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