JPH0867554A - Production of oxide magnetic material - Google Patents
Production of oxide magnetic materialInfo
- Publication number
- JPH0867554A JPH0867554A JP6230532A JP23053294A JPH0867554A JP H0867554 A JPH0867554 A JP H0867554A JP 6230532 A JP6230532 A JP 6230532A JP 23053294 A JP23053294 A JP 23053294A JP H0867554 A JPH0867554 A JP H0867554A
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- powder
- magnetic material
- producing
- edta
- oxide magnetic
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、スイッチング電源等に
搭載されるＭｎ−Ｚｎフェライトの製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing Mn-Zn ferrite mounted on a switching power supply or the like.
【０００２】[0002]
【従来の技術】従来、スイッチング電源等の磁性材料と
しては、Ｍｎ−Ｚｎフェライトが用いられており、その
駆動周波数は、２００ｋＨｚ程度もしくはそれ以下であ
った。又、近年の小型化、軽量化に伴い、駆動周波数が
２００ｋＨｚ〜５００ｋＨｚ、さらには、１ＭＨｚまで
の高周波化の検討、開発が進められている。2. Description of the Related Art Conventionally, Mn-Zn ferrite has been used as a magnetic material for switching power supplies and the like, and its driving frequency has been about 200 kHz or less. Further, with the recent miniaturization and weight reduction, studies and developments have been made to increase the driving frequency to 200 kHz to 500 kHz, and further to 1 MHz.
【０００３】しかしながら、この高周波数で従来のＭｎ
−Ｚｎ系フェライトを使用した場合、フェライトのパワ
ーロスの増大による発熱が極めて大きいため、その機能
を果たすことができないという欠点があった。However, at this high frequency, conventional Mn
When the Zn-based ferrite is used, there is a drawback that the function cannot be fulfilled because the heat generated by the increase in the power loss of the ferrite is extremely large.
【０００４】[0004]
【発明が解決しようとする課題】一般的なＭｎ−Ｚｎ系
フェライトの製造方法は、鉄、マンガン、亜鉛の各酸化
物粉末をボールミル等で混合した後、予焼し、微粉砕工
程、造粒工程を経てプレスを行い、圧粉体を作製する。
この圧粉体を焼結することによって、目的とするフェラ
イト焼結体を得ている。A general method for producing Mn-Zn ferrite is to mix iron, manganese, and zinc oxide powders in a ball mill or the like, and then pre-burn, finely pulverize, and granulate. Pressing is performed through the steps to produce a green compact.
By sintering this green compact, the target ferrite sintered body is obtained.
【０００５】ところで、高周波領域での磁気特性には、
渦電流損失が大きくかかわっており、この渦電流損失を
如何に低減するかが、極めて重要な課題となっている。
この渦電流損失を低減するためには、焼結体の粒界相、
又は、スピネル相の電気抵抗を向上させることが不可欠
である。By the way, the magnetic characteristics in the high frequency range are as follows:
The eddy current loss is greatly involved, and how to reduce this eddy current loss is an extremely important issue.
In order to reduce this eddy current loss, the grain boundary phase of the sintered body,
Alternatively, it is essential to improve the electrical resistance of the spinel phase.
【０００６】スピネル相自身の電気抵抗を向上させる方
策としては、Ｆｅ2+とＦｅ3+間の電子のホッピング現象
を少なくすることが考えられる。これには、焼結雰囲気
の酸素分圧を高めることによって、Ｆｅ2+を減少させる
ことや、Ｔｉ4+、Ｓｎ4+を含有せしめ、Ｆｅ3+と置換す
ること等で、電子のホッピング現象の発生を抑制する方
法がある。As a measure for improving the electric resistance of the spinel phase itself, it is considered to reduce the electron hopping phenomenon between Fe 2+ and Fe 3+ . The electron hopping phenomenon can be achieved by increasing the oxygen partial pressure in the sintering atmosphere to reduce Fe 2+ , or by adding Ti 4+ or Sn 4+ to replace Fe 3+. There is a method of suppressing the occurrence of.
【０００７】しかし、前者はＦｅ2+の極端な減少による
初透磁率μｉの著しい低下や、保磁力Ｈｃの増大等の磁
気特性の低下を招くという問題がある。又、後者のＴｉ
4+、Ｓｎ4+等の添加法では、パワーロスの温度特性にお
いて、ミニマムポイント（パワーロス値が最小となる温
度）が、低温側へ著しく低下してしまうため、好ましく
ない。さらに、両者いずれの方法でも、スピネル相自身
の電気抵抗を向上させても、思ったほど焼結体の電気抵
抗は大きくならないという最大の欠点がある。However, the former has a problem in that the initial permeability μi is remarkably lowered due to the extreme decrease of Fe 2+ , and the magnetic characteristics are deteriorated such as the increase of the coercive force Hc. Also, the latter Ti
The addition method of 4+ , Sn 4+, etc. is not preferable because the minimum point (the temperature at which the power loss value becomes the minimum) in the temperature characteristic of power loss is significantly lowered to the low temperature side. Further, both of the methods have the greatest drawback that the electrical resistance of the sintered body does not increase as much as expected even if the electrical resistance of the spinel phase itself is improved.
【０００８】粒相界の電気抵抗の向上の方法としては、
ＳｉＯ2，ＣａＯの他に第３の元素を添加することによ
り、高抵抗な粒界相を形成せしめる方法が一般的であ
る。このＳｉＯ2，ＣａＯの他に第３の元素を添加する
方法は、フェライト焼結体の抵抗を向上させる方法とし
ては最も効果的であり、最もよく使用されている方策で
ある。又、この時結晶粒径を小さくすることで、個々の
粒内で発生する渦電流を小さくすることや、粒界相を越
えて渦電流が流れたとしても、結晶粒子が小さいと粒界
相の数が増加し、これを遮断すること等から、高抵抗粒
界相を効率よく活用することができ、著しい効果があ
る。この結晶粒径を小さくする方法として、粉末粒径を
小さくし、できるだけ低い温度で焼結することが不可欠
である。As a method for improving the electric resistance of the grain phase boundary,
A general method is to form a high-resistance grain boundary phase by adding a third element in addition to SiO 2 and CaO. The method of adding a third element in addition to SiO 2 and CaO is the most effective method for improving the resistance of the ferrite sintered body and is the most widely used method. Also, at this time, by reducing the crystal grain size, the eddy current generated in each grain is reduced, and even if the eddy current flows beyond the grain boundary phase, if the crystal grain is small, the grain boundary phase The number of particles increases and the particles are cut off, so that the high resistance grain boundary phase can be efficiently utilized, which is a remarkable effect. As a method of reducing the crystal grain size, it is essential to reduce the powder grain size and sinter at a temperature as low as possible.
【０００９】従来のＭｎ−Ｚｎフェライトの製造方法で
は、先にも述べた如く、Ｆｅ，Ｍｎ，Ｚｎの各酸化物を
混合し、仮焼し、微粉砕することで、微細な粉末を得
る。しかしながら、この方法で得られる仮焼粉の粒径
は、０.５〜１μｍ、又は、それ以上の粒径であり、か
なり大きいため、長時間の微粉砕によって微細な粉末を
得て焼結体を製造しなければならない。In the conventional method for producing Mn-Zn ferrite, fine powder is obtained by mixing Fe, Mn, and Zn oxides, calcining them, and pulverizing them, as described above. However, the particle size of the calcined powder obtained by this method is 0.5 to 1 μm or more, and it is quite large. Therefore, fine powder is obtained by pulverization for a long time to obtain a sintered body. Must be manufactured.
【００１０】この方法では、長時間の粉砕を要するた
め、コスト高になるばかりでなく、粉砕中における粉砕
機の内壁、又はボール等からの不純物の混入が多く、そ
れに伴う磁気特性劣化が著しいため、好ましくない。
又、一般的に、仮焼はコスト高を避けるため、大気中に
て７００〜１１００℃で行うが、得られる仮焼粉の生成
相には、スピネル相とヘマタイト相が混在する。ここ
で、スピネル相とヘマタイト相の粒径や被粉砕性は異な
るため、微粉砕後の粒度分布がブロードになり、結晶粒
径が不揃いとなる原因となる。又、スピネル単相にする
ためには、大気中で１２００℃以上に加熱するか、窒素
中で仮焼を行わなければならない。これは、コスト高に
なるばかりでなく、仮焼粉の粒径が成長により大きくな
るため、より長時間の微粉砕が必要となり、前述のよう
にコスト高、磁気特性の劣化を引き起こす。Since this method requires long-time pulverization, not only the cost becomes high, but also many impurities are mixed from the inner wall of the pulverizer, balls or the like during pulverization, resulting in remarkable deterioration of magnetic characteristics. , Not preferable.
Further, generally, calcination is performed at 700 to 1100 ° C. in the atmosphere in order to avoid high cost, but the spinel phase and the hematite phase are mixed in the produced phase of the calcinated powder obtained. Here, since the spinel phase and the hematite phase have different particle sizes and pulverizability, the particle size distribution after fine pulverization becomes broad, which causes irregular crystal grain sizes. Further, in order to obtain a spinel single phase, it is necessary to heat it to 1200 ° C. or higher in the atmosphere or to perform calcination in nitrogen. This not only increases the cost, but also increases the particle size of the calcined powder due to growth, which requires fine pulverization for a longer period of time, resulting in high cost and deterioration of magnetic properties as described above.
【００１１】又、従来の製法で得た仮焼粉は、そのまま
成形したのでは粉末粒径が粗いため、低温で焼結した場
合焼結体密度が低く、磁気特性も低くなってしまうとい
う欠点がある。さらに、焼結体密度を向上させるため
に、焼結温度を高めると、結晶粒径が大きくなり、渦電
流損失が大となり好ましくない。Further, the calcined powder obtained by the conventional manufacturing method has a coarse powder particle size when molded as it is. Therefore, when sintered at low temperature, the density of the sintered body is low and the magnetic properties are also low. There is. Further, if the sintering temperature is increased in order to improve the density of the sintered body, the crystal grain size becomes large and the eddy current loss becomes large, which is not preferable.
【００１２】以上、述べたように、従来のフェライト製
造工程では、高周波領域で優れた磁気特性を示す微細な
結晶粒径を有したＭｎ−Ｚｎフェライトは得られなかっ
た。As described above, in the conventional ferrite manufacturing process, Mn-Zn ferrite having a fine crystal grain size and exhibiting excellent magnetic characteristics in a high frequency region could not be obtained.
【００１３】又、以上に詳述した渦電流損失もさること
ながら、ヒステリシス損失、初透磁率μｉ、飽和磁束密
度Ｂｓ、残留磁束密度Ｂｒ、保磁力Ｈｃ等の諸磁気特性
も電源用フェライト材として重要な特性項目である。Further, in addition to the eddy current loss described in detail above, various magnetic characteristics such as hysteresis loss, initial permeability μi, saturation magnetic flux density Bs, residual magnetic flux density Br, coercive force Hc, etc. are also found as a ferrite material for a power supply. It is an important characteristic item.
【００１４】これらの諸特性については、焼結体組織を
如何に原子レベルに及ぶまで均一にするかが重要であ
る。従来の方法では、固相反応により予焼粉末を得てい
るため、原子の拡散が不充分であり、得られた予焼粉も
不均一な物しか得られず、優れた磁気特性が得られない
という欠点を有していた。With respect to these characteristics, it is important how the texture of the sintered body is made uniform up to the atomic level. In the conventional method, since the pre-calcined powder is obtained by the solid-phase reaction, the diffusion of atoms is insufficient, and the pre-calcined powder obtained is non-uniform, and excellent magnetic properties are obtained. It had the drawback of not being.
【００１５】さらに、この問題を解決すべき方法とし
て、噴霧焙焼法によりＦｅ，Ｍｎ，Ｚｎの塩酸溶液から
予焼粉を得る、いわゆるルスナー法がある。この方法で
は、溶液状態で各元素の混合が可能であるため、原子レ
ベルで均一な混合が可能となる。しかしながら、塩化亜
鉛（ＺｎＣｌ2）の蒸気圧が高いことによる組成ずれが
著しく、目的にかなう組成粉末を製造できない。Further, as a method for solving this problem, there is a so-called Lusner method in which a pre-baked powder is obtained from a hydrochloric acid solution of Fe, Mn and Zn by a spray roasting method. In this method, since each element can be mixed in a solution state, uniform mixing can be performed at the atomic level. However, the compositional deviation due to the high vapor pressure of zinc chloride (ZnCl 2 ) is significant, and it is not possible to produce a composition powder that meets the purpose.
【００１６】以上のように、いずれの従来の技術を用い
ても、高周波領域で優れた磁気特性を有するＭｎ−Ｚｎ
系フェライト材を得ることは困難であった。As described above, Mn-Zn having excellent magnetic characteristics in the high frequency region is obtained by using any of the conventional techniques.
It was difficult to obtain a ferrite material.
【００１７】従って、本発明の技術的課題は、数百ｋＨ
ｚ〜１ＭＨｚ付近までの高周波領域においてパワーロス
が小さく、また、そのミニマムポイントが６０℃〜８０
℃近辺にあり、他の諸磁気特性にも優れた低損失酸化物
磁性材料の製造方法を提供することにある。Therefore, the technical problem of the present invention lies in several hundred kH.
Power loss is small in the high frequency range from z to around 1 MHz, and the minimum point is 60 ° C to 80 ° C.
It is to provide a method for producing a low-loss oxide magnetic material that is in the vicinity of ° C and is excellent in other magnetic properties.
【００１８】[0018]
【課題を解決するための手段】前記の問題を解決するた
め、種々の検討を行った結果、本発明者は、Ｆｅ，Ｍ
ｎ、Ｚｎを含むＥＤＴＡ錯体の溶液を噴霧して得られる
粉末を原料とし、混合、造粒、成形、焼結することによ
り、極めて微細な組織からなり、極めて電気抵抗が高
く、高周波領域で優れた磁気特性を有するＭｎ−Ｚｎフ
ェライトが製造できることを見い出したものである。即
ち、Ｆｅ，Ｍｎ，Ｚｎの各元素は、ＥＤＴＡ錯体の溶液
状態で原子レベルの均一な混合が可能となる。この溶液
を加熱・乾燥し溶液の溶媒を除去すると、残留物が自己
燃焼を起こす。この燃焼は、極めて短時間で燃焼し、終
了するため、粉体粒径が非常に微細、且つ均一な粉末を
得ることが可能となる。さらに、種々の検討を加えた結
果、得られた粉末の生成相をスピネル単相で得るのに適
したＥＤＴＡの混合量を見い出したものである。本発明
によれば、ルスナー法のように炉内を高温に保持せずに
噴霧が可能なため、量産に大規模なプラントを必要とせ
ず、工業的価値も高い。又、ＥＤＴＡを含む溶媒には工
業的に安価である水が好ましい。さらに、工業的には、
加熱方法として、スプレー造粒のように噴霧乾燥を用い
ると得られる粉体物性が取り扱いに適した物となる。As a result of various studies in order to solve the above problems, the present inventors have found that Fe, M
A powder obtained by spraying a solution of EDTA complex containing n and Zn is used as a raw material, and by mixing, granulating, molding and sintering, it has an extremely fine structure, has an extremely high electrical resistance, and is excellent in the high frequency range. It has been found that Mn-Zn ferrite having excellent magnetic properties can be produced. That is, the elements Fe, Mn, and Zn can be uniformly mixed at the atomic level in the solution state of the EDTA complex. When this solution is heated and dried to remove the solvent of the solution, the residue causes self-combustion. Since this combustion burns and ends in an extremely short time, it is possible to obtain a powder having a very fine powder particle diameter and a uniform particle diameter. Further, as a result of various investigations, the amount of EDTA mixed suitable for obtaining the spinel single phase as the product phase of the obtained powder was found. According to the present invention, since spraying can be performed without maintaining the inside of the furnace at a high temperature unlike the Rusner method, a large-scale plant is not required for mass production, and the industrial value is high. Further, water, which is industrially inexpensive, is preferable as the solvent containing EDTA. Furthermore, industrially,
If spray drying such as spray granulation is used as the heating method, the obtained powder properties will be suitable for handling.
【００１９】本発明において、金属硝酸塩の総ｍｏｌ数
とＥＤＴＡのｍｏｌ数の比が９５：５〜５０：５０とし
た理由は、種々の検討の結果、この混合量の範囲のみ
で、得られる粉末の生成相がスピネル単相になるからで
ある。すなわち、ＥＤＴＡの量としてｍｏｌ比で５％未
満で行った場合、得られた粉末にヘマタイト相が現れ、
磁気特性の低下を招くからである。In the present invention, the reason why the ratio of the total number of moles of metal nitrate to the number of moles of EDTA is 95: 5 to 50:50 is as a result of various investigations, and powders obtained only within this mixing amount range. This is because the produced phase of becomes a spinel single phase. That is, when the amount of EDTA was less than 5% by mol, a hematite phase appeared in the obtained powder,
This is because the magnetic properties are deteriorated.
【００２０】[0020]
【作用】本発明の製造方法により得られるフェライト粉
末は、溶液状態での混合なので原子状態で極めて均一な
混合が可能であり、また、極めて短時間での自己燃焼に
よりフェライト粉末が形成させるので、その粉体粒径は
微細で、且つ、粒度分布はシャープである。このフェラ
イト粉末を使用して混合−造粒−成形−焼結の各工程を
経て得られる焼結体は、極めて微細な組織を有し、電気
抵抗が高く、高周波領域で優れたパワーロス特性を示
し、組成が均一であることから、その他の磁気特性にも
優れたＭｎ−Ｚｎフェライトである。Since the ferrite powder obtained by the production method of the present invention is mixed in a solution state, extremely uniform mixing in an atomic state is possible, and since the ferrite powder is formed by self-combustion in an extremely short time, The powder particle size is fine and the particle size distribution is sharp. A sintered body obtained through the steps of mixing-granulation-molding-sintering using this ferrite powder has an extremely fine structure, high electric resistance, and excellent power loss characteristics in a high frequency region. Since the composition is uniform, the Mn-Zn ferrite is excellent in other magnetic properties.
【００２１】[0021]
【実施例】以下に、本発明の実施例を説明する。EXAMPLES Examples of the present invention will be described below.
【００２２】（実施例１）本実施例では、金属塩として
硝酸塩を用いた例で説明する。高純度のＦｅ（Ｎ
Ｏ3）3，Ｍｎ（ＮＯ3）2，Ｚｎ（ＮＯ3）2をＦｅ2Ｏ3，
ＭｎＯ，ＺｎＯの換算で、５３ｍｏｌ％−３９ｍｏｌ％
−８ｍｏｌ％となるように秤量し、純水中に溶解した。
この溶液にＥＤＴＡをＦｅ（ＮＯ3）3，Ｍｎ（Ｎ
Ｏ3）2，Ｚｎ（ＮＯ3）2の総ｍｏｌ数に対し、２５ｍｏ
ｌ％となるように添加し、よく混合した。次に、この溶
液を炉内温度を３５０℃に保持した炉内へ噴霧した。そ
の後、炉内で反応し得られた生成物を見たところ粉末状
となっていた。(Embodiment 1) In this embodiment, an example in which a nitrate is used as a metal salt will be described. High-purity Fe (N
O 3 ) 3 , Mn (NO 3 ) 2 and Zn (NO 3 ) 2 are replaced with Fe 2 O 3 ,
53 mol% -39 mol% in terms of MnO and ZnO
It was weighed to be -8 mol% and dissolved in pure water.
EDTA was added to this solution as Fe (NO 3 ) 3 , Mn (N
25 mo based on the total mol number of O 3 ) 2 and Zn (NO 3 ) 2.
It was added to be 1% and mixed well. Next, this solution was sprayed into the furnace in which the temperature inside the furnace was kept at 350 ° C. Then, the product obtained by the reaction in the furnace was found to be powdery.
【００２３】この粉末をＸ線回折により生成相を調査し
たところ、Ｍｎ−Ｚｎフェライトスピネル単相となって
いた。又、この粉末の組成を分析した結果、５２.９Ｆ
ｅＯ3−３９.３ＭｎＯ−７.８ＺｎＯ（ｍｏｌ％）であ
り、組成にずれがほとんど生じていないことが判った。
この粉末に０.０４ｗｔ％のＳｉＯ2、０.０８ｗｔ％の
ＣａＯ、及び０.０６ｗｔ％のＶ2Ｏ5を添加し、ボール
ミルにて混合した。その後、バインダーとしてポリビニ
ルアルコールを添加し、バインダー混合を行った。得ら
れたスラリーを乾燥造粒後、φ２５×φ１５×ｔ５ｍｍ
のトロイダル形状に２ｔ／ｃｍ2の圧力で成形した。得
られた成形体を酸素分圧をコントロールした窒素気流中
８５０〜１２００℃の温度で焼結した。When the generated phase of this powder was examined by X-ray diffraction, it was found to be a Mn-Zn ferrite spinel single phase. The composition of this powder was analyzed and found to be 52.9F.
It was eO 3 -39.3 MnO-7.8 ZnO (mol%), and it was found that there was almost no deviation in composition.
To this powder, 0.04 wt% of SiO 2 , 0.08 wt% of CaO, and 0.06 wt% of V 2 O 5 were added and mixed by a ball mill. Then, polyvinyl alcohol was added as a binder, and the binder was mixed. After drying and granulating the obtained slurry, φ25 × φ15 × t5mm
Toroidal shape with a pressure of 2 t / cm 2 . The obtained molded body was sintered at a temperature of 850 to 1200 ° C. in a nitrogen stream whose oxygen partial pressure was controlled.
【００２４】酸素分圧、焼結温度を変化させ製造した焼
結体の中で、最も優れたパワーロス特性を示す試料の温
度特性を図１（曲線ａ）に示す。なお、測定条件は、周
波数が１ＭＨｚ、振幅磁場が５００Ｇである。又、この
焼結体のパワーロス以外の諸磁気・電気特性を表１に示
す。FIG. 1 (curve a) shows the temperature characteristic of the sample showing the most excellent power loss characteristic among the sintered bodies produced by changing the oxygen partial pressure and the sintering temperature. The measurement conditions are a frequency of 1 MHz and an amplitude magnetic field of 500G. Table 1 shows various magnetic and electrical characteristics of the sintered body other than the power loss.
【００２５】[0025]
【表１】 [Table 1]
【００２６】（実施例２）ＥＤＴＡの添加量を変化さ
せ、他の条件は実施例１と同様な製法で作製した粉末の
スピネル化率とＥＤＴＡの添加量の関係を図２に示す。
本発明の請求の範囲、即ちＥＤＴＡの添加量が、５〜５
０ｍｏｌ％でスピネル単相が得られる。従来の製造方法
により得られる予焼粉は、スピネル化率が通常４０〜５
０％であることと比較すると、本発明の製法が優れてい
ることがわかる。ＥＤＴＡの添加量が５０ｍｏｌ％を越
えると、ヘマタイト相が現れ、スピネル化率が従来の予
焼粉と同程度にまで低下してしまう。なお、ＥＤＴＡの
添加量が５ｍｏｌ％以下では自己燃焼を起こさなかっ
た。(Example 2) The relationship between the spinelization rate of the powder produced by the same manufacturing method as in Example 1 and the addition amount of EDTA under different conditions is shown in FIG.
In the claims of the present invention, that is, the amount of EDTA added is 5 to 5
A spinel single phase is obtained at 0 mol%. The pre-baked powder obtained by the conventional manufacturing method usually has a spinelization rate of 40 to 5
It can be seen that the production method of the present invention is superior as compared with 0%. When the amount of EDTA added exceeds 50 mol%, a hematite phase appears and the spinelization rate is reduced to the same level as that of the conventional pre-baked powder. When the amount of EDTA added was 5 mol% or less, self-combustion did not occur.
【００２７】また、この粉末を実施例１と同様の条件で
焼結して得られた焼結体のパワーロス特性とＥＤＴＡの
添加量との関係を図３に示す。なお、測定条件は周波数
が１ＭＨｚ、振幅磁場が５００Ｇ、温度が８０℃であ
る。図３に同時に示されている、後に説明する比較例と
比べた時、本発明の請求の範囲、即ちＥＤＴＡの添加量
が、５〜５０ｍｏｌ％で最適であることを示している。FIG. 3 shows the relationship between the power loss characteristics of the sintered body obtained by sintering this powder under the same conditions as in Example 1 and the amount of EDTA added. The measurement conditions are a frequency of 1 MHz, an amplitude magnetic field of 500 G, and a temperature of 80 ° C. When compared with the comparative example to be described later, which is also shown in FIG. 3, it is shown that the claimed range of the present invention, that is, the addition amount of EDTA is 5 to 50 mol%, which is the optimum.
【００２８】（実施例３）実施例１と同様に、高純度の
Ｆｅ（ＮＯ3）3，Ｍｎ（ＮＯ3）2，Ｚｎ（ＮＯ3）2をＦ
ｅ2Ｏ3，ＭｎＯ，ＺｎＯの換算で、５３ｍｏｌ％−３９
ｍｏｌ％−８ｍｏｌ％となるように秤量し、純水中に溶
解した。この溶液にＥＤＴＡをＦｅ（ＮＯ3）3，Ｍｎ
（ＮＯ3）2，Ｚｎ（ＮＯ3）2の総ｍｏｌ数に対し、２５
ｍｏｌ％となるように添加し、よく混合した。次に、こ
の溶液をステンレスビーカーに入れ、熱風乾燥炉で加熱
し、水分を蒸発させ、反応させて後、得られた生成物を
観察したところ、粉末状になっていた。この生成物に実
施例１と同じ添加物を添加し、以下、実施例１と同様な
方法により得られた焼結体のパワーロス特性を図１（曲
線ｂ）に示す。(Example 3) As in Example 1, high purity Fe (NO 3 ) 3 , Mn (NO 3 ) 2 and Zn (NO 3 ) 2 were mixed with F.
In terms of e 2 O 3 , MnO, and ZnO, 53 mol% -39
It was weighed to be mol% -8 mol% and dissolved in pure water. EDTA was added to this solution as Fe (NO 3 ) 3 , Mn
For the total number of moles of (NO 3 ) 2 and Zn (NO 3 ) 2 , 25
It was added to be mol% and mixed well. Next, this solution was put into a stainless beaker, heated in a hot air drying oven to evaporate water, and after reacting, the product obtained was observed and found to be powdery. The same additive as in Example 1 was added to this product, and the power loss characteristics of the sintered body obtained by the same method as in Example 1 are shown in FIG. 1 (curve b).
【００２９】（比較例）高純度の酸化鉄、酸化マンガ
ン、酸化亜鉛を用いて５３Ｆｅ2Ｏ3−３９ＭｎＯ−８Ｚ
ｎＯ（ｍｏｌ％）となるように秤量し、ボールミルで混
合後、約１０００℃で予焼した。この予焼粉を前記実施
例と同様ＳｉＯ2，ＣａＯ，Ｖ2Ｏ5を添加し、ボールミ
ルにて混合、さらに、乾燥造粒後、実施例と同様に成
形、焼結した。 これら条件を変化させた焼結体の中
で、最も優れたパワーロス特性の温度特性を、図１（曲
線ｃ）に示す。又、表１に、この焼結体の諸磁気特性を
示す。図１より、本発明において、パワーロスが大幅に
改善されていることがわかる。又、表１より、本発明に
おいて、ρ、Ｂ15、Ｂｒ、及びＨｃの諸特性が大幅に改
善されていることがわかる。Comparative Example 53 Fe 2 O 3 -39MnO-8Z was prepared by using high-purity iron oxide, manganese oxide and zinc oxide.
It was weighed so as to be nO (mol%), mixed with a ball mill, and then pre-baked at about 1000 ° C. SiO 2 , CaO, and V 2 O 5 were added to the pre-baked powder as in the above-mentioned Examples, mixed by a ball mill, further dried and granulated, and then molded and sintered in the same manner as in the Examples. FIG. 1 (curve c) shows the most excellent temperature characteristic of the power loss characteristic among the sintered bodies obtained by changing these conditions. Table 1 shows various magnetic characteristics of this sintered body. It can be seen from FIG. 1 that the power loss is significantly improved in the present invention. Further, it can be seen from Table 1 that the characteristics of ρ, B 15 , Br, and Hc are greatly improved in the present invention.
【００３０】[0030]
【発明の効果】以上の実施例で述べたように、Ｆｅ，Ｍ
ｎ，Ｚｎを含む金属の硝酸塩の総ｍｏｌ数に対し、ＥＤ
ＴＡを混合することで、生成相がスピネル単相の微細な
粉末を得ることができる。これを混合、造粒、成形、焼
結することにより、極めて微細な組織を有する焼結体が
得られ、パワーロス及び諸磁気特性を改善することがで
き、スイッチング電源等に搭載した場合発熱量が小さ
い、優れた低損失磁性材料を提供できる。As described in the above embodiments, Fe, M
ED for the total mol number of metal nitrates including n and Zn
By mixing TA, it is possible to obtain a fine powder having a spinel single phase as a production phase. By mixing, granulating, molding and sintering this, a sintered body having an extremely fine structure can be obtained, power loss and various magnetic characteristics can be improved, and the amount of heat generated when mounted on a switching power supply etc. It is possible to provide a small and excellent low loss magnetic material.
【図１】本実施例及び比較例により作製した焼結体のパ
ワーロスの温度特性を示す特性図。FIG. 1 is a characteristic diagram showing temperature characteristics of power loss of sintered bodies produced in this example and a comparative example.
【図２】ＥＤＴＡの添加量とスピネル化率の関係を示す
特性図。FIG. 2 is a characteristic diagram showing the relationship between the amount of EDTA added and the spinelization rate.
【図３】ＥＤＴＡの添加条件とパワーロスの関係を示す
特性図。FIG. 3 is a characteristic diagram showing the relationship between EDTA addition conditions and power loss.
ａ 実施例１による焼結体のパワーロスの温度特性を示
す曲線 ｂ 実施例３による焼結体のパワーロスの温度特性を示
す曲線 ｃ 比較例による焼結体のパワーロスの温度特性を示す
曲線a curve showing the temperature characteristic of the power loss of the sintered body according to Example 1 b curve showing the temperature characteristic of the power loss of the sintered body according to Example 3 c curve showing the temperature characteristic of the power loss of the sintered body according to Comparative Example
Claims (4)
ＥＤＴＡ（エチレンジアミン四酢酸）との錯体の溶液を
加熱して得られるフェライト粉末を原料とし、混合、造
粒、成形、焼結することを特徴とする酸化物磁性材料の
製造方法。1. Mixing, granulating, molding, and sintering using a ferrite powder obtained by heating a solution of a complex of a metal salt containing Fe, Mn, and Zn and EDTA (ethylenediaminetetraacetic acid) as a raw material. A method for producing an oxide magnetic material, comprising:
法において、前記金属塩が金属の硝酸塩であることを特
徴とする酸化物磁性材料の製造方法。2. The method for producing an oxide magnetic material according to claim 1, wherein the metal salt is a nitrate of a metal.
材料の製造方法において、金属の硝酸塩の総ｍｏｌ数と
ＥＤＴＡのｍｏｌ数との比が９５：５〜５０：５０の範
囲であることを特徴とする酸化物磁性材料の製造方法。3. The method for producing an oxide magnetic material according to claim 1 or 2, wherein the ratio of the total number of moles of metal nitrate to the number of moles of EDTA is in the range of 95: 5 to 50:50. A method for producing an oxide magnetic material, comprising:
の酸化物磁性材料の製造方法において、前記錯体の溶液
を加熱する方法が噴霧熱乾燥法であることを特徴とする
酸化物磁性材料の製造方法。4. The method for producing an oxide magnetic material according to claim 1, claim 2 or claim 3, wherein the method of heating the solution of the complex is a spray heat drying method. Manufacturing method of magnetic material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6230532A JPH0867554A (en) | 1994-08-30 | 1994-08-30 | Production of oxide magnetic material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6230532A JPH0867554A (en) | 1994-08-30 | 1994-08-30 | Production of oxide magnetic material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0867554A true JPH0867554A (en) | 1996-03-12 |
Family
ID=16909227
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6230532A Pending JPH0867554A (en) | 1994-08-30 | 1994-08-30 | Production of oxide magnetic material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0867554A (en) |
-
1994
- 1994-08-30 JP JP6230532A patent/JPH0867554A/en active Pending
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