JP2740648B2 - Method for producing soft magnetic oxide material - Google Patents
Method for producing soft magnetic oxide materialInfo
- Publication number
- JP2740648B2 JP2740648B2 JP62132206A JP13220687A JP2740648B2 JP 2740648 B2 JP2740648 B2 JP 2740648B2 JP 62132206 A JP62132206 A JP 62132206A JP 13220687 A JP13220687 A JP 13220687A JP 2740648 B2 JP2740648 B2 JP 2740648B2
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- Prior art keywords
- soft magnetic
- magnetic oxide
- powder
- oxide material
- composition
- Prior art date
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- Magnetic Ceramics (AREA)
- Soft Magnetic Materials (AREA)
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は、軟磁性酸化物材料の製造方法に関する。
［従来の技術］
現在、軟磁性酸化物材料としては、MFe2O4（Ｍは、M
n,Zn,Ni,Co,Fe,Cu,Li,Mg）の化学式で記述されるスピネ
ル構造の材料が用いられている。この材料を得るための
原料の合成方法としては、例えば、NiZnFe2O4を得る場
合には、NiO,ZnO,Fe2O3の粉体を所定の割合で湿式混合
し、次に乾燥し、仮焼するという手順を踏む方法を用い
ている。
また、この材料を製品化するには、合成した原料に各
種の添加剤を湿式混合した後、乾燥造粒し、成形し、焼
成するという手順を踏む必要がある。
しかし、現在のところ、CoO,NiO,MnO2等の原料として
微細なものを得ることが難しい。このため、単なる湿式
混合により得られる混合物では、上記原料の混合状態が
不均一となって組成変動が生じる。これにより、焼成に
よって得られる焼成体の粒径にばらつきが生じる。その
結果、磁化過程が不ぞろいとなってノイズが発生するな
ど、軟磁性酸化物に要求される磁気特性（透磁率、温度
特性、周波数特性など）が低下する。また、この焼成体
の粒径のばらつきにより、軟磁性酸化物の機械的強度も
低下する。
［発明が解決しようとする問題点］
この発明は上記の実情に鑑みてなされたもので、焼成
体の粒径のばらつきを抑え、軟磁性酸化物の磁気特性及
び機械的特性の向上を図ることが可能な軟磁性酸化物材
料の製造方法を提供することを目的とするものである。
［問題点を解決するための手段］
上記目的を達成するためにこの発明では、まず第１の
工程としてMn,Ni,Co,Zn,Mg,Liの少なくとも１つを含む
塩（例えば硝酸塩，硫酸塩又は塩化物）とFeの塩（例え
ば硝酸塩，硫酸塩又は塩化物）とを所望材料の組成割合
より足りない組成割合の範囲内で混合する。
次に第２の工程として、上記第１の工程で得られた混
合物を沈澱生成液、例えば塩のモル数の1.1〜2.0倍のし
ゅう酸溶液に滴下して沈澱を形成する。
そして、第３の工程として、上記第２の工程で得られ
た共沈体を仮焼して合成した原料にFe2O3とZnOの粉体を
所望材料の組成となるように湿式混合する。
［作用］
上記の如くこの発明は、軟磁性酸化物材料の製造を、
原料粉体の固相反応によって行なうのではなく、各原料
イオンの水溶液よりそのイオンの共沈体を形成すること
により行っている。そして共沈体を仮焼して合成した原
料にFe2O3とZnOの粉体を所望材料の組成となるように混
合する。
このような構成によれば、原料を均一に分布させるこ
とができるので、組成変動を極力小さくすることができ
る。これにより、粒径のそろった焼成体が得ることがで
きる。この焼成体の組織の均一化により、透磁率、温度
特性、周波数特性などいった軟磁性酸化物に要求される
磁気特性の向上及び安定化を図ることができる。
また、この組織の均一化により、さらに、軟磁性酸化
物の機械的強度の向上も図ることができる。
［実施例］
実施例１
まず、この発明に係る軟磁性酸化物材料の製造方法の
一実施例について図を参照しながら説明する。なお、以
下の説明では、MnZnFe2O4を製造する場合を代表として
説明する。
Mn(NO3)2・６H2OとFeSO4・２H2Oを、MnとFeとのモル
比が1:6.2となるように秤量混合した（図のステップS1
参照）後、純水を加えて1mol/lの水溶液となるように
し、MnイオンとFeイオンを含む水溶液を調製した。この
混合溶液50mlをあらかじめ調製した沈澱生成液であるし
ゅう酸溶液50ml（Mn2+とFe2+の合計モル数の1.4倍の
量）中へ滴下し、Mn2+とFe2+のしゅう酸塩として共沈さ
せた（図のステップS2参照）。この時の滴下には、マグ
ネチックスターラーを用い、温度40℃で１時間の滴下時
間を要した。このようにして得られたしゅう酸共沈物
を、濾過、洗浄した（図のステップS3参照）後、100℃
で乾燥した（図のステップS4参照）。この乾燥資料を80
0℃で２時間熱処理（仮焼）して粉体を得た（図のステ
ップS5参照）。この時得られた粉体の粒径は0.1〜0.7μ
ｍである。
この粉体にZnOとCoOおよびFe2O3を各々前記得られた
粉体重量の1/16,1/20,1/10を秤量して加え、ポットミル
を用いて湿式で24時間粉砕・混合を行った（図のステッ
プS6参照）。粉砕し混合した原料を乾燥した後、これに
粘結剤としてPVA（ポリビニルアルコール）水溶液を少
量（原料に対し1wt％）添加して成形用の粉体とする
（図のステップS7参照）。
この粉体を環状に成形した（図のステップS8参照）
後、焼成炉を用いて焼成した（図のステップS9参照）。
この焼成は大気中で毎時100℃で1350℃まで昇温した
後、この状態を２時間保持し、次に、毎時100℃で降温
するように行なった。
得られた焼成体の比透磁率を100kHzで測定した結果12
20であった。
従来の方法は、MnO,Fe2O3,Zno,CoOを粉体の状態で混
合、仮焼、焼成するという工程で行なわれ、フェライト
は各粉体間の固相反応として得られる。この実施例の製
造方法と従来の製造方法とを比較するため、上記と同じ
組成で、従来の製造方法による試料を作成した。この比
透磁率は1120で、この実施例の方法では、同組成にもか
かわらず良好な結果が得られる事がわかった（表参
照）。
その理由は従来の製造方法における固相反応では、原
料自体の粒径が大きい事や、原料の均一混合状態が各々
の粉体の凝集性の違い、および粒子表面状態の違いのた
めに得られにくく、このため不均一組成となりやすいの
に対し、この実施例の製造方法によれば、共沈を利用す
る事により、従来の製造方法では混合が容易でなかった
Mnの酸化物とFeの酸化物との混合物を、比較的容易に得
られることができるためであると考えられる。
実施例２
次に、この発明に係る軟磁性酸化物材料の製造方法の
他の実施例を説明する。
Ni(NO3)2・６H2OとFeSO4・２H2Oを、NiとFeとのモル
比が1:3.2となるように秤量、混合した後、純水を加え
て1mol/lの水溶液となるように溶解させ、NiイオンとFe
イオンを含む水溶液を調整した。この混合溶液50mlをあ
らかじめ調製したしゅう酸溶液50ml（Ni2+とFe2+の合計
モル数の1.5倍の量）中へ滴下し、Mn2+とFe2+のしゅう
酸塩として共沈させた。生成した共沈体を先の実施例１
と同じく濾過、洗浄、乾燥、仮焼する事によって、粒径
0.05〜0.3μｍの粉体が得られる。
この粉体に、ZnOとCoOおよびFe2O3を各々前記得られ
た粉体重量の1/9,1/8,1/9を秤量して加え、ポットミル
を用いて湿式で粉砕・混合を行った。粉砕し混合した原
料を乾燥の後、粘結剤としてPVA（ポリビニルアルコー
ル）水溶液を少量（原料に対し約1wt％）添加して、成
形用の粉体とする。
この粉体を環状に成形し、焼成炉を用いて焼成した。
この焼成は、大気中で毎時100℃で1400℃まで昇温した
後、この状態を２時間保持し、次に、毎時100℃で降温
するように行なった。
得られた焼成体の比透磁率を100kHzで850であった。
一方、同様の組成の試料を共沈ではなく粉体原料の混
合によって製造した試料の比透磁率は770であった。
［発明の効果］
上記の如く、従来軟磁性酸化物材料の必要特性とし
て、透磁率、周波数特性、比抵抗等の磁気特性があり、
これらのばらつきを小さくできる方法が要望されてい
た。
これに対し、この発明に係る製造方法は、ばらつきの
大きな要素となる原料粉体、特に従来の製造法では良好
な粉体特性が得られない組成Ａを、比較的良好な粉体特
性の得られる他の組成Ｂと同時に共沈させる事によっ
て、従来の製造法よりも微細で均一な原料を得た後、そ
れに組成Ｂと必要なら他の組成を添加して粉体原料を作
るようにしたものである。
前述のように軟磁性酸化物材料の必要特性は、周波数
特性、比抵抗等で、これらを制御するには組成ＡとＢの
共沈原料に、組成Ｂ及びその他添加物を付加する事によ
り可能である。
この発明の製造方法では、組成ＡとＢの共沈より製造
した原料が、微細で均一な粒径を持ち、焼結しやすいと
いう特性をもつため、従来問題となっていた原料の不均
一性に起因した各種の欠陥が減少し、必要特性が向上す
るという効果がある。また、上記原料に各種添加剤を加
えても、従来最も焼結性に悪影響を与えた組成Ａの原料
の粉体特性の向上により、特性の向上を図る事ができ
る。
さらに、仮焼後に特に微細な原料を容易に得ることが
できるFe2O3とZnOの粉体を追加する工程を設けることに
より、容易に所望の組成割合とすることができ、焼結後
の軟磁性酸化物材料の各組成の制御を容易に行い所望の
磁気特性を得ることができる。
また、この発明の製造方法により工業的に多数の部品
を製造すれば、ばらつきの低減も図れ、製造経費の低減
も可能となる。The present invention relates to a method for producing a soft magnetic oxide material. [Prior Art] Currently, MFe 2 O 4 (M is M
A material having a spinel structure described by a chemical formula of (n, Zn, Ni, Co, Fe, Cu, Li, Mg) is used. As a method of synthesizing the raw materials for obtaining this material, for example, when NiZnFe 2 O 4 is obtained, NiO, ZnO, Fe 2 O 3 powders are wet-mixed at a predetermined ratio, and then dried, The method of taking the procedure of calcining is used. Further, in order to commercialize this material, it is necessary to take a procedure of wet-mixing various additives to the synthesized raw material, followed by dry granulation, molding and firing. However, at present, it is difficult to obtain fine materials such as CoO, NiO, and MnO 2 . For this reason, in a mixture obtained by simple wet mixing, the mixing state of the above-mentioned raw materials becomes non-uniform, and a composition variation occurs. Thereby, the particle size of the fired body obtained by firing varies. As a result, the magnetic characteristics (magnetic permeability, temperature characteristics, frequency characteristics, etc.) required for the soft magnetic oxide are reduced, for example, the magnetization process becomes irregular and noise occurs. Further, the mechanical strength of the soft magnetic oxide also decreases due to the variation in the particle size of the fired body. [Problems to be Solved by the Invention] The present invention has been made in view of the above circumstances, and aims to suppress variation in the particle size of a fired body and improve the magnetic properties and mechanical properties of a soft magnetic oxide. It is an object of the present invention to provide a method for producing a soft magnetic oxide material capable of performing the following. [Means for Solving the Problems] In order to achieve the above object, according to the present invention, as a first step, a salt containing at least one of Mn, Ni, Co, Zn, Mg, and Li (eg, nitrate, sulfuric acid, etc.) A salt or chloride) and a salt of Fe (for example, nitrate, sulfate or chloride) are mixed in a composition ratio less than the composition ratio of the desired material. Next, as a second step, the mixture obtained in the first step is dropped into a precipitation product solution, for example, an oxalic acid solution having 1.1 to 2.0 times the number of moles of the salt to form a precipitate. Then, as a third step, powders of Fe 2 O 3 and ZnO are wet-mixed with a raw material synthesized by calcining the coprecipitate obtained in the second step so as to have a desired material composition. . [Operation] As described above, the present invention provides a method for producing a soft magnetic oxide material,
Rather than performing the reaction by a solid-phase reaction of the raw material powder, it is performed by forming a coprecipitate of each raw material ion from an aqueous solution. Then, powders of Fe 2 O 3 and ZnO are mixed with the raw material synthesized by calcining the coprecipitate so as to have a desired material composition. According to such a configuration, since the raw materials can be uniformly distributed, the composition fluctuation can be minimized. Thereby, a fired body having a uniform particle size can be obtained. By homogenizing the structure of the fired body, it is possible to improve and stabilize the magnetic properties required for the soft magnetic oxide, such as the magnetic permeability, temperature characteristics, and frequency characteristics. Further, by making the structure uniform, the mechanical strength of the soft magnetic oxide can be further improved. EXAMPLES Example 1 First, an example of a method for manufacturing a soft magnetic oxide material according to the present invention will be described with reference to the drawings. In the following description, a case where MnZnFe 2 O 4 is manufactured will be described as a representative. Mn (NO 3 ) 2 .6H 2 O and FeSO 4 .2H 2 O were weighed and mixed such that the molar ratio of Mn to Fe was 1: 6.2 (step S1 in the figure).
After that, pure water was added to make a 1 mol / l aqueous solution to prepare an aqueous solution containing Mn ions and Fe ions. Was added dropwise to this mixture of oxalic acid solution 50ml is previously prepared precipitated product liquid solution 50ml (Mn 2+ and 1.4 times the amount of the total number of moles of Fe 2+) in, oxalic acid Mn 2+ and Fe 2+ It was co-precipitated as a salt (see step S2 in the figure). The dropping at this time required a dropping time of 1 hour at a temperature of 40 ° C. using a magnetic stirrer. The oxalic acid coprecipitate thus obtained was filtered and washed (see step S3 in the figure), and then heated to 100 ° C.
(See step S4 in the figure). 80 of this dry material
Heat treatment (calcination) was performed at 0 ° C. for 2 hours to obtain a powder (see step S5 in the figure). The particle size of the powder obtained at this time is 0.1-0.7μ
m. To this powder, ZnO, CoO and Fe 2 O 3 were respectively weighed and weighed 1/16, 1/20, 1/10 of the weight of the obtained powder, and wet-milled and mixed for 24 hours using a pot mill. (See step S6 in the figure). After the pulverized and mixed raw material is dried, a small amount (1 wt% based on the raw material) of a PVA (polyvinyl alcohol) aqueous solution is added as a binder to obtain a powder for molding (see step S7 in the figure). This powder was formed into a ring (see step S8 in the figure)
Thereafter, firing was performed using a firing furnace (see step S9 in the figure).
In this firing, the temperature was raised to 1350 ° C. at 100 ° C./hour in the atmosphere, this state was maintained for 2 hours, and then the temperature was lowered at 100 ° C./hour. The relative permeability of the obtained fired body was measured at 100 kHz.
It was 20. In the conventional method, MnO, Fe 2 O 3 , Zno, and CoO are mixed in a powder state, and calcined and fired. Ferrite is obtained as a solid-phase reaction between the powders. In order to compare the production method of this example with the conventional production method, a sample was prepared with the same composition as described above and by the conventional production method. The relative magnetic permeability was 1120, and it was found that good results were obtained with the method of this example despite the same composition (see Table). The reason is that in the solid-phase reaction in the conventional production method, the raw material itself has a large particle size, and a uniform mixing state of the raw materials is obtained due to a difference in the cohesiveness of each powder and a difference in the particle surface state. However, according to the production method of this example, mixing was not easy by the conventional production method by using coprecipitation, whereas
It is considered that a mixture of an oxide of Mn and an oxide of Fe can be obtained relatively easily. Embodiment 2 Next, another embodiment of the method for producing a soft magnetic oxide material according to the present invention will be described. Ni (NO 3 ) 2 .6H 2 O and FeSO 4 .2H 2 O are weighed and mixed such that the molar ratio of Ni and Fe is 1: 3.2, and then pure water is added thereto to add a 1 mol / l aqueous solution. Dissolve so that Ni ion and Fe
An aqueous solution containing ions was prepared. 50 ml of this mixed solution was dropped into 50 ml of oxalic acid solution prepared in advance (1.5 times the total number of moles of Ni 2+ and Fe 2+ ), and coprecipitated as oxalate of Mn 2+ and Fe 2+. Was. The generated coprecipitate was used in Example 1 above.
Filter, wash, dry and calcine as in
A powder of 0.05-0.3 μm is obtained. To this powder, ZnO, CoO and Fe 2 O 3 were each weighed at 1/9, 1/8, 1/9 of the weight of the obtained powder, and ground and mixed in a wet manner using a pot mill. went. After the pulverized and mixed raw material is dried, a small amount of a PVA (polyvinyl alcohol) aqueous solution (about 1 wt% based on the raw material) is added as a binder to form a powder for molding. This powder was formed into a ring shape and fired using a firing furnace.
In this firing, the temperature was raised to 1400 ° C. at 100 ° C./hour in the atmosphere, this state was maintained for 2 hours, and then the temperature was lowered at 100 ° C./hour. The relative permeability of the obtained fired body was 850 at 100 kHz. On the other hand, the relative permeability of a sample produced by mixing powder materials instead of coprecipitation with a sample having the same composition was 770. [Effects of the Invention] As described above, the necessary characteristics of the conventional soft magnetic oxide material include magnetic characteristics such as magnetic permeability, frequency characteristics, and specific resistance.
There has been a demand for a method that can reduce these variations. On the other hand, the production method according to the present invention converts the raw material powder, which is an element having large variation, particularly the composition A, from which good powder characteristics cannot be obtained by the conventional production method, to obtain relatively good powder characteristics. After obtaining a finer and more uniform raw material than the conventional manufacturing method by co-precipitating simultaneously with the other composition B, a powder raw material is made by adding the composition B and another composition if necessary. Things. As described above, the necessary characteristics of the soft magnetic oxide material are frequency characteristics, specific resistance, and the like, and these can be controlled by adding the composition B and other additives to the coprecipitated raw material of the compositions A and B. It is. In the production method of the present invention, the raw material produced from the co-precipitation of the compositions A and B has the characteristics of having a fine and uniform particle size and sintering easily. This has the effect of reducing various defects caused by the above and improving required characteristics. In addition, even if various additives are added to the above-mentioned raw materials, the characteristics can be improved by improving the powder characteristics of the raw material of the composition A, which has most adversely affected the sintering property. Furthermore, by providing a step of adding powder of Fe 2 O 3 and ZnO that can easily obtain particularly fine raw materials after calcination, it is possible to easily obtain a desired composition ratio, and after sintering, It is possible to easily control each composition of the soft magnetic oxide material and obtain desired magnetic properties. In addition, if a large number of parts are manufactured industrially by the manufacturing method of the present invention, variations can be reduced and manufacturing costs can be reduced.
【図面の簡単な説明】
図はこの発明に係る軟磁性酸化物材料の製造方法の一実
施例の工程を説明するための図である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining the steps of one embodiment of the method for producing a soft magnetic oxide material according to the present invention.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 山田 学 刈谷市昭和町１丁目１番地 日本電装株 式会社内 (72)発明者 白崎 信一 茨城県新治郡桜村竹園３の610の201 (56)参考文献 特開 昭61−141669（ＪＰ，Ａ) ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Manabu Yamada 1-1 1-1 Showacho, Kariya City Nippondenso Co., Ltd. In the formula company (72) Inventor Shinichi Shirasaki 610-201 201, Takezono, Sakuramura, Niiji, Ibaraki (56) References JP-A-61-141669 (JP, A)
Claims (1)
の塩とを所望の軟磁性酸化物材料としての組成割合より
FeおよびZnが足りない組成割合の範囲内で混合する第１
の工程と、 この第１の工程で得られた混合物を沈殿生成液に滴下し
て共沈体を形成する第２の工程と、 この第２の工程で得られた共沈体を仮焼して合成した原
料にFe2O3とZnOの粉体を所望の軟磁性酸化物材料の組成
となるように湿式混合する第３の工程と、 よりなることを特徴とする軟磁性酸化物材料の製造方
法。(57) [Claims] Salt containing at least one of Mn, Ni, Co, Zn, Mg, Li and Fe
From the composition ratio of the desired soft magnetic oxide material
The first in which Fe and Zn are mixed within the range of the composition ratio that is insufficient
A second step of dropping the mixture obtained in the first step into a precipitation liquid to form a coprecipitate; and calcining the coprecipitate obtained in the second step. A third step of wet mixing Fe 2 O 3 and ZnO powder with the raw material synthesized in such a manner as to obtain a desired composition of the soft magnetic oxide material. Production method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62132206A JP2740648B2 (en) | 1987-05-28 | 1987-05-28 | Method for producing soft magnetic oxide material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62132206A JP2740648B2 (en) | 1987-05-28 | 1987-05-28 | Method for producing soft magnetic oxide material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63296319A JPS63296319A (en) | 1988-12-02 |
| JP2740648B2 true JP2740648B2 (en) | 1998-04-15 |
Family
ID=15075874
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62132206A Expired - Fee Related JP2740648B2 (en) | 1987-05-28 | 1987-05-28 | Method for producing soft magnetic oxide material |
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| Country | Link |
|---|---|
| JP (1) | JP2740648B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5105660B2 (en) * | 2000-12-08 | 2012-12-26 | 京セラ株式会社 | Ferrite material and ferrite core using the same |
| CN110776314A (en) * | 2019-12-23 | 2020-02-11 | 贵州正业龙腾新材料开发有限公司 | Wide-high-frequency anti-EMI manganese-zinc ferrite material and preparation method thereof |
| CN115784320B (en) * | 2022-11-15 | 2024-02-27 | 安徽大学 | Gas-sensitive material and preparation method and application thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60141669A (en) * | 1983-12-27 | 1985-07-26 | 松下電器産業株式会社 | Manufacture of high density spinel ferrite sintered body |
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1987
- 1987-05-28 JP JP62132206A patent/JP2740648B2/en not_active Expired - Fee Related
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| Publication number | Publication date |
|---|---|
| JPS63296319A (en) | 1988-12-02 |
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