JPH11176680A - Manufacture of core - Google Patents
Manufacture of coreInfo
- Publication number
- JPH11176680A JPH11176680A JP9362958A JP36295897A JPH11176680A JP H11176680 A JPH11176680 A JP H11176680A JP 9362958 A JP9362958 A JP 9362958A JP 36295897 A JP36295897 A JP 36295897A JP H11176680 A JPH11176680 A JP H11176680A
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- Japan
- Prior art keywords
- powder
- molding
- magnetic
- core
- sheets
- 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.)
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- Soft Magnetic Materials (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、チョークコイル等
に用いられる高性能の磁芯の製造方法に関する。The present invention relates to a method for manufacturing a high-performance magnetic core used for a choke coil or the like.
【０００２】[0002]
【従来の技術】高周波で用いられるチョークコイルとし
て、軟磁性フェライト磁芯や圧粉磁芯が使用されてい
る。これらのうち、フェライト磁芯は、飽和磁束密度が
小さいという欠点を有している。これに対して、軟磁性
金属粉末を成形して作製される圧粉磁芯は、フェライト
磁芯に比べて、著しく大きい飽和磁束密度を有するた
め、直流重畳特性に優れているという長所を有してい
る。しかし、圧粉磁芯は、金属粉末を有機バインダー等
と混合して圧縮成形して作製するため、透磁率が低く、
また透磁率の高周波特性が悪いという欠点を有してい
る。2. Description of the Related Art Soft magnetic ferrite cores and dust cores are used as choke coils used at high frequencies. Among them, the ferrite core has a disadvantage that the saturation magnetic flux density is small. On the other hand, a dust core made by molding a soft magnetic metal powder has an advantage that it has an extremely high saturation magnetic flux density compared to a ferrite core, and thus has excellent DC superimposition characteristics. ing. However, since the dust core is produced by mixing metal powder with an organic binder and compression molding, the magnetic permeability is low,
It also has the disadvantage that the high-frequency characteristics of magnetic permeability are poor.
【０００３】また、近年の電子機器における小型化要請
に伴う電子部品の小型化の要求に対し、圧粉磁芯の磁気
特性に対しても、高特性化が強く望まれている。これ
は、圧粉磁芯の小型化を達成しつつ、コイルのインダク
タンスは、同等であることが要求されているためであ
り、そのためには、圧粉磁芯の透磁率の向上及び周波数
特性の改善が必須である。[0003] In addition, in response to the demand for miniaturization of electronic parts accompanying the recent demand for miniaturization of electronic equipment, it is strongly desired to improve the magnetic properties of the dust core. This is because it is required that the inductance of the coil be equivalent while achieving the miniaturization of the dust core, and for that purpose, the permeability of the dust core is improved and the frequency characteristics are improved. Improvement is essential.
【０００４】圧粉磁芯の透磁率を向上させる方法は、大
別して以下の二点が考えられる。 金属粉末の充填率を上げる。 金属粉末の形状を扁平化させた粉末の長軸方向を圧粉
磁芯の磁路方向に配向させ反磁界係数を下げる。Methods for improving the magnetic permeability of a dust core are roughly classified into the following two points. Increase the filling rate of metal powder. The long axis direction of the flattened metal powder is oriented in the direction of the magnetic path of the dust core to reduce the demagnetizing coefficient.
【０００５】また、の方法では、磁路方向の粉末の断
面積が小さくなり、渦電流損失の低減による周波数特性
の改善も期待できる。In the method (1), the cross-sectional area of the powder in the direction of the magnetic path is reduced, and improvement in frequency characteristics due to reduction of eddy current loss can be expected.
【０００６】の手段として、例えば、成形圧力を上げ
る、バインダーの条件を種々変化させる、二つ以上の異
種形状、粒度、組成等の異なる粉末の配合等が検討され
ている。しかし、それらの方法による圧粉磁芯の透磁率
の改善は、既に研究がし尽くされており、例えば、成形
圧力を上げる方法にしても、金型破損の増加等、製造コ
ストの面からも無視できない状況にある。As means for increasing the pressure, for example, increasing the molding pressure, changing the conditions of the binder in various ways, blending two or more powders having different shapes, particle sizes, compositions, and the like have been studied. However, the improvement of the magnetic permeability of the dust core by these methods has already been thoroughly studied.For example, even if the method of increasing the molding pressure is used, the mold cost is increased and the manufacturing cost is reduced. The situation cannot be ignored.
【０００７】の方法に関しても、金属粉末にバインダ
ーを加えて、圧縮成形を行う従来の製造方法では、圧粉
磁芯の形状が、リング状等の圧縮方向が磁芯の磁路に対
して直角方向である場合は、扁平化粉末の磁路方向への
配向がある程度期待できるが、成形用原料粉末の金型の
壁面との抵抗による配向乱れ等により、配向が不十分な
ものとなる等の問題があった。[0007] In the conventional manufacturing method in which a binder is added to metal powder and compression molding is performed, the shape of the dust core is such that the compression direction such as a ring shape is perpendicular to the magnetic path of the magnetic core. In the case of the direction, the orientation of the flattened powder in the direction of the magnetic path can be expected to some extent, but the orientation becomes insufficient due to the disorder of the orientation due to the resistance of the material powder for molding to the wall surface of the mold, and the like. There was a problem.
【０００８】[0008]
【発明が解決しようとする課題】本発明の目的は、扁平
化させた粉末を印刷積層法によって磁路方向に十分に配
向させることにより、高い透磁率で、しかも、高周波特
性に優れた磁芯の製造方法を提供することにある。SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic core having high magnetic permeability and excellent high frequency characteristics by sufficiently orienting flattened powder in the direction of a magnetic path by a printing lamination method. It is to provide a manufacturing method of.
【０００９】[0009]
【課題を解決するための手段】本発明は、扁平状の軟磁
性金属粉末とバインダーを用いて印刷積層法によってシ
ートを作製し、該シートを重ねて加圧成形して、成形体
を得、該成形体を打ち抜く磁芯の製造方法である。According to the present invention, a sheet is produced by a printing lamination method using a flat soft magnetic metal powder and a binder, and the sheets are stacked and pressed to obtain a molded article. This is a method for manufacturing a magnetic core by punching the molded body.
【００１０】また、本発明は、上記の磁芯の製造方法に
おいて、前記成形体の厚さは、１０ｍｍ以下である磁芯
の製造方法である。[0010] The present invention also relates to the above-mentioned method of manufacturing a magnetic core, wherein the molded body has a thickness of 10 mm or less.
【００１１】また、本発明は、上記の磁芯の製造方法に
おいて、前記扁平状の軟磁性金属粉末は、アスペクト比
が５〜４０である磁芯の製造方法である。Further, the present invention is the above-mentioned method for producing a magnetic core, wherein the flat soft magnetic metal powder has an aspect ratio of 5 to 40.
【００１２】本発明では、図１（ａ）に示すように、扁
平状の粉末１を磁芯の磁路方向に十分に配向させるため
に、成形方法について印刷積層法を用いて、磁路方向と
印刷積層方向が一致するように積層する。このことによ
り、扁平状の粉末１は、せん断応力によって磁路方向に
十分に配向させることが可能となり、従来の方法で作製
された圧粉磁芯中の従来の粉末２［図１（ｂ）］の配向
状態よりも高特性の磁芯が得られる。In the present invention, as shown in FIG. 1A, in order to sufficiently orient the flat powder 1 in the direction of the magnetic path of the magnetic core, a printing lamination method is used as a molding method. And the printing lamination direction is matched. Thus, the flat powder 1 can be sufficiently oriented in the direction of the magnetic path by the shear stress, and the conventional powder 2 in the dust core manufactured by the conventional method [FIG. ] Can be obtained.
【００１３】本発明で用いられる軟磁性金属粉末として
は、鉄系の軟磁性金属の粒子からなる粉末を用いること
が好ましい。鉄系の軟磁性金属としては、Ｆｅ、Ｆｅ−
Ｓｉ−Ａｌ、Ｆｅ−Ｎｉ、Ｆｅ−Ｃｏ、Ｆｅ−Ｓｉ、Ｆ
ｅ−Ｐ、Ｆｅ−Ｍｏ−Ｎｉ等より、必要とされる磁気特
性に応じて選択される。As the soft magnetic metal powder used in the present invention, it is preferable to use a powder comprising iron-based soft magnetic metal particles. Fe-based soft magnetic metals include Fe, Fe-
Si-Al, Fe-Ni, Fe-Co, Fe-Si, F
It is selected from e-P, Fe-Mo-Ni, etc. according to required magnetic characteristics.
【００１４】扁平状の軟磁性金属粉末は、必要な組成の
インゴットを振動ミル等で粗粉砕した粉末を作製し、次
に、圧延、せん断作用を持つボールミル等の粉砕メディ
アを用いた粉砕機で粉砕することにより得られる。上記
のインゴット粉砕法による粗粉砕の代わりに、ガスアト
マイズ法、水アトマイズ法、回転ディスク法等を用いる
ことも可能である。The flat soft magnetic metal powder is prepared by roughly pulverizing an ingot of a required composition with a vibrating mill or the like to produce a powder, and then using a pulverizer using a pulverizing medium such as a ball mill having rolling and shearing action. Obtained by grinding. Instead of the coarse crushing by the ingot crushing method, a gas atomizing method, a water atomizing method, a rotating disk method, or the like can be used.
【００１５】扁平状の粉末のアスペクト比（径／厚さ）
は、５〜４０程度が好ましく、実際の径としては、１０
〜８０μｍが高い磁気特性を得るため望ましい。Aspect ratio (diameter / thickness) of flat powder
Is preferably about 5 to 40, and the actual diameter is 10
-80 µm is desirable for obtaining high magnetic properties.
【００１６】本発明で用いられるバインダーとしては、
各種有機高分子やシリコーン樹脂を用いることが可能で
あり、必要とされる磁心の特性に応じて各種選択され
る。The binder used in the present invention includes:
Various organic polymers and silicone resins can be used, and various types are selected according to the required characteristics of the magnetic core.
【００１７】[0017]
【発明の実施の形態】扁平状の軟磁性金属粉末にバイン
ダーを混合して粉末ペーストを得る。この粉末ペースト
を用いて印刷積層法により、扁平状粉末が磁路方向に配
向された、厚さが５００μｍ以下のシートを得る。この
シートを積層して、加圧成形し、所定の形状に打ち抜
く。BEST MODE FOR CARRYING OUT THE INVENTION A powder paste is obtained by mixing a binder with a flat soft magnetic metal powder. Using this powder paste, a sheet having a thickness of 500 μm or less, in which the flat powder is oriented in the direction of the magnetic path, is obtained by a printing lamination method. The sheets are laminated, pressed and punched into a predetermined shape.
【００１８】[0018]
【実施例】（実施例１）Ｆｅ−Ｓｉ−Ａｌ合金のインゴ
ット粉末をディスクミルで粗粉砕し、得られた粉末を５
０ｈｒ粉砕し、長手方向が平均４０μｍ、厚さが平均２
μｍであり、アスペクト比が約２０である扁平状の粉末
を得た。(Example 1) Ingot powder of an Fe-Si-Al alloy was roughly pulverized by a disk mill, and
0hr crushed, average 40μm in longitudinal direction, average thickness 2
A flat powder having a thickness of about 20 μm and an aspect ratio of about 20 was obtained.
【００１９】得られた扁平状の粉末を表１の比率でバイ
ンダ、溶剤と配合し、配合物を三本ロールで混練して粉
末ペーストを得た。The obtained flat powder was blended with a binder and a solvent in the ratio shown in Table 1, and the blend was kneaded with a three-roll mill to obtain a powder paste.
【００２０】 [0020]
【００２１】次に、粉末ペーストを用い、印刷積層法に
より、厚さが２００μｍのシートを得た。得られたシー
トを重ねて０.５，１，４，７，１０ｍｍとなるように
加圧成形した後、その成形体をφ１５ｍｍ×１０ｍｍの
トロイダル形状に打ち抜き、７００℃×２ｈｒ熱処理を
行い、磁芯を得た。又、扁平状の粉末のアスペクト比を
２，５，１０，２０，４０と変え、成形体の厚さを４ｍ
ｍに一定にしたシートより、上記と同じ形状に打ち抜
き、同様の処理を行って圧粉磁芯を得た。Next, a sheet having a thickness of 200 μm was obtained by a printing lamination method using the powder paste. The obtained sheets were stacked and pressed under a pressure of 0.5, 1, 4, 7, and 10 mm, and the formed body was punched into a toroidal shape of φ15 mm × 10 mm, heat-treated at 700 ° C. × 2 hr, and subjected to magnetic treatment. I got a wick. Also, the aspect ratio of the flat powder was changed to 2, 5, 10, 20, 40 and the thickness of the compact was 4 m.
The sheet having a constant m was punched out in the same shape as above, and the same treatment was performed to obtain a dust core.
【００２２】比較例として、上記成形用原料粉末をφ１
５ｍｍ×１０ｍｍの金型を使用し、厚さが０.５，１，
４，７，１０ｍｍとなるように圧縮成形し、圧粉磁芯を
得て同様に熱処理を行った。なお、粉末の充填率は、全
試料において、約７５％となるように作製した。As a comparative example, the above-mentioned molding raw material powder was φ1
Using a mold of 5mm x 10mm, thickness 0.5, 1,
It was compression-molded to 4, 7, 10 mm to obtain a dust core and heat-treated similarly. The powder was prepared so that the filling rate of the powder was about 75% in all samples.
【００２３】次に、この圧粉磁芯に巻線をして、ＹＨＰ
製インピーダンスアナライザー４１９４Ａで周波数１０
０ｋＨｚでの透磁率を測定した。成形体の厚さを変えた
場合の測定結果を表２に示す。また、アスペクト比を変
えた場合の測定結果を表３に示す。なお、表３中、＊は
従来の方法を示す。Next, a wire is wound around this dust core, and YHP
Frequency 10 with a 4194A impedance analyzer
The magnetic permeability at 0 kHz was measured. Table 2 shows the measurement results when the thickness of the molded body was changed. Table 3 shows the measurement results when the aspect ratio was changed. In Table 3, * indicates a conventional method.
【００２４】 [0024]
【００２５】 [0025]
【００２６】表２より、本発明の方法による試料厚さが
１０ｍｍ以下の磁芯の透磁率は、従来の方法での圧粉磁
芯の透磁率に比べ、高い値を示していることがわかる。
また、本発明の方法によるトロイダルを積層して作製し
た厚さ１０ｍｍの磁芯は、従来の方法での厚さ１０ｍｍ
の圧粉磁芯よりも高透磁率となっていることがわかる。From Table 2, it can be seen that the magnetic permeability of the magnetic core having a sample thickness of 10 mm or less according to the method of the present invention shows a higher value than the magnetic permeability of the dust core according to the conventional method. .
The magnetic core having a thickness of 10 mm produced by laminating the toroids according to the method of the present invention has a thickness of 10 mm according to the conventional method.
The magnetic permeability is higher than that of the dust core.
【００２７】また、表３より、アスペクト比が５以上で
あると、従来の方法よりも高透磁率であることがわか
る。Table 3 shows that when the aspect ratio is 5 or more, the magnetic permeability is higher than that of the conventional method.
【００２８】図２に、本発明の方法及び従来の方法によ
る、厚さ０.５ｍｍの磁芯の透磁率の周波数特性を示
す。図２より、本発明の方法での磁芯の透磁率の方が、
より高周波数まで一定値を示しているのがわかる。FIG. 2 shows the frequency characteristics of the magnetic permeability of a magnetic core having a thickness of 0.5 mm according to the method of the present invention and the conventional method. From FIG. 2, the magnetic permeability of the magnetic core in the method of the present invention is
It can be seen that it shows a constant value up to higher frequencies.
【００２９】[0029]
【発明の効果】以上、述べたように、本発明によれば、
高い透磁率で、しかも、高周波特性に優れた磁芯の製造
方法を提供することが可能である。As described above, according to the present invention,
It is possible to provide a method for manufacturing a magnetic core having high magnetic permeability and excellent high-frequency characteristics.
【図１】本発明の方法と従来の方法における粉末の配向
状態を模式的に示した図。図１（ａ）は、本発明の方法
を示す図。図１（ｂ）は、従来の方法を示す図。FIG. 1 is a diagram schematically showing an orientation state of powder in a method of the present invention and a conventional method. FIG. 1A is a diagram showing a method of the present invention. FIG. 1B is a diagram showing a conventional method.
【図２】試料の厚さが０.５ｍｍのときの磁芯の透磁率
の周波数特性を示す図。FIG. 2 is a diagram showing frequency characteristics of the magnetic permeability of a magnetic core when the thickness of a sample is 0.5 mm.
１ 扁平状の粉末 ２ 従来の粉末 Ａ 本発明 Ｂ 従来 DESCRIPTION OF SYMBOLS 1 Flat powder 2 Conventional powder A Present invention B Conventional
Claims (3)
用いて印刷積層法によってシートを作製し、該シートを
重ねて加圧成形して、成形体を得、該成形体を打ち抜く
ことを特徴とする磁芯の製造方法。1. A sheet is produced by a printing and laminating method using a flat soft magnetic metal powder and a binder, the sheets are stacked and pressed to obtain a molded body, and the molded body is punched. A method of manufacturing a magnetic core.
て、前記成形体の厚さは、１０ｍｍ以下であることを特
徴とする磁芯の製造方法。2. The method for manufacturing a magnetic core according to claim 1, wherein the thickness of the molded body is 10 mm or less.
おいて、前記扁平状の軟磁性金属粉末は、アスペクト比
が５〜４０であることを特徴とする磁芯の製造方法。3. The method for manufacturing a magnetic core according to claim 1, wherein the flat soft magnetic metal powder has an aspect ratio of 5 to 40.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9362958A JPH11176680A (en) | 1997-12-11 | 1997-12-11 | Manufacture of core |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9362958A JPH11176680A (en) | 1997-12-11 | 1997-12-11 | Manufacture of core |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH11176680A true JPH11176680A (en) | 1999-07-02 |
Family
ID=18478165
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9362958A Withdrawn JPH11176680A (en) | 1997-12-11 | 1997-12-11 | Manufacture of core |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH11176680A (en) |
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Cited By (23)
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|---|---|---|---|---|
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