JPH05335135A - Oxide magnetic material for high frequency - Google Patents
Oxide magnetic material for high frequencyInfo
- Publication number
- JPH05335135A JPH05335135A JP4141384A JP14138492A JPH05335135A JP H05335135 A JPH05335135 A JP H05335135A JP 4141384 A JP4141384 A JP 4141384A JP 14138492 A JP14138492 A JP 14138492A JP H05335135 A JPH05335135 A JP H05335135A
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- max
- magnetic material
- present
- type ferrite
- 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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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は，高周波帯域で用いられ
る酸化物磁性材料に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxide magnetic material used in a high frequency band.
【０００２】[0002]
【従来の技術】従来，この種の軟磁性材料には，金属に
比べ電気抵抗が高く，周波数特性が高周波化できること
から，Ｍｎ−Ｚｎ系フェライトやＮｉ−Ｚｎ系フェライ
トや，Ｍｎ−Ｍｇ系フェライトで代表されるようなスピ
ネル型フェライト焼結体が使用されてきた。2. Description of the Related Art Conventionally, this kind of soft magnetic material has a higher electric resistance than a metal and has a higher frequency characteristic, so that a Mn-Zn ferrite, a Ni-Zn ferrite, or a Mn-Mg ferrite is used. The spinel type ferrite sintered body represented by the above has been used.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら，これら
の材料は，通常約１０ＭＨｚ以下の周波数に適応した磁
芯材料であり，１００ＭＨｚ以上の周波数帯域では，損
失が極めて大きく，磁芯材料としては使用が不可能であ
るという欠点を有した。However, these materials are usually magnetic core materials adapted to a frequency of about 10 MHz or less, and the loss is extremely large in the frequency band of 100 MHz or more, so that they cannot be used as magnetic core materials. It had the drawback of being impossible.
【０００４】したがって，産業界における高周波化によ
る情報処理等に対応できなくなりつつあった。Therefore, it is becoming difficult to cope with information processing and the like due to high frequency in the industrial world.
【０００５】そこで，本発明の技術的課題は，安価に製
造できるスピネル型フェライト焼結体を高周波帯での磁
芯材料として適用不可能となる欠点を排除し，１００Ｍ
Ｈｚ以上での適用を可能とした高周波用酸化物磁性材料
を提供することにある。Therefore, the technical problem of the present invention is to eliminate the drawback that a spinel type ferrite sintered body which can be manufactured at a low cost cannot be applied as a magnetic core material in a high frequency band, and is 100M.
An object is to provide an oxide magnetic material for high frequencies, which can be applied at frequencies above Hz.
【０００６】[0006]
【課題を解決するための手段】本発明者は，種々検討を
重ねた結果，Ｎｉ，Ｃｕ，Ｃｏ，Ｆｅの酸化物を主成分
として含有するスピネル型フェライト焼結体において，
組成比がＮｉ(1-x) ・Ｃｕx ・Ｆｅ(2-n) ・Ｃｏy ・Ｏ
4 ，但し，０．０２≦ｎ≦０．９５，０．０３≦ｘ≦
０．６０，０．０１≦ｙ≦０．３０，で表わされること
を特徴とすることにより，１００ＭＨｚ以上の周波数帯
に適用できるスピネル型フェライト材料を工業的に有用
に製造できることを発見した。As a result of various studies, the present inventor has found that in a spinel type ferrite sintered body containing oxides of Ni, Cu, Co and Fe as main components,
The composition ratio is Ni (1-x) , Cu x , Fe (2-n) , Co y , O
4 , provided that 0.02 ≤ n ≤ 0.95, 0.03 ≤ x ≤
It has been discovered that a spinel ferrite material applicable to a frequency band of 100 MHz or more can be industrially usefully produced by being characterized by being expressed by 0.60, 0.01 ≦ y ≦ 0.30.
【０００７】ここで，本発明における特性の評価には記
号としてμ100MHz，Ｑmax ，ｆQmax，Ｓ．Ｔ．を使用し
ている。μ100MHzは１００ＭＨｚにおける実効透磁率を
表し，この値はインダクタンスを高くとれることから一
般的には高い方が良いが，高過ぎると高周波特性が悪く
なるという関係にある。また，Ｑmax はＱ（損失係数ｔ
ａｎδの逆数）の最大値を示すものであり，磁芯材料と
しては高い程高性能となる。更に，ｆQmaxはＱmax が最
大値を示した周波数を示し，この周波数前後が磁芯用材
料としては有効に作動できる周波数帯域となる。したが
って，１００ＭＨｚに適用できる材料としては，μ
100MHzが適度に高く，ｆQmaxは１００ＭＨｚ以上で，Ｑ
は最低でも２０以上は必要とされる。Here, in the evaluation of the characteristics in the present invention, as symbols, μ 100 MHz , Q max , f Qmax , S. T. Are using. μ 100 MHz represents the effective magnetic permeability at 100 MHz, and it is generally preferable that this value is high because the inductance can be made high, but if it is too high, the high frequency characteristics deteriorate. Also, Q max is Q (loss factor t
It shows the maximum value of the reciprocal of an δ), and the higher the core material, the higher the performance. Further, f Qmax indicates the frequency at which Q max shows the maximum value, and the frequency band around this frequency is the frequency band in which the magnetic core material can effectively operate. Therefore, the material applicable to 100MHz is μ
100MHz is moderately high, f Qmax is 100MHz or more, Q
Is required to be at least 20 or more.
【０００８】本発明の酸化物磁性材料の組成比Ｎｉ
(1-x) ・Ｃｕx ・Ｆｅ(2-n) ・Ｃｏy ・Ｏ4 において，
ｎの値の範囲を０．０２≦ｎ≦０．９５と限定したの
は，０．０２以上でＱmax が著しく向上し，０．９５以
上でＱmax が著しく低下するためであり，ｎ＝０．０２
〜０．９５の範囲で損失が著しく小さい材料が提供でき
るためである。また，上記組成式において，ｘの値の範
囲を０．０３≦ｘ≦０．６０と限定したのは，０．０３
以上では焼結温度が著しく低下し，焼結炉の設備費用や
焼結エネルギーの低減に加え焼結体の結晶組織の制御が
容易になるという工業的有用性を有し，一方，ｘの値が
０．６０以上ではＱmax がｘ＝０よりも小さい値とな
り，磁芯特性上好ましくない効果を生じるようになるた
めである。また，上記組成式において，ｙの値を０．０
１≦ｙ≦０．３０と限定したのは，０．０１以下ではｆ
Qmaxが１００ＭＨｚ以下となり，本発明の課題である１
００ＭＨｚ以上に適用できる高周波用磁芯材料とならな
くなるためであり，ｙの値が０．３０以上ではＣｏ添加
のｆQmax向上の効果が認められなくなるのに加え，Ｑ
max が減少し，比較的高価なＣｏを添加することが，有
益性を生じなくなり，工業的には不利益となるからであ
る。The composition ratio Ni of the oxide magnetic material of the present invention
In (1-x) · Cu x · Fe (2-n) · Co y · O 4,
The reason why the range of the value of n is limited to 0.02 ≦ n ≦ 0.95 is that Q max is remarkably improved at 0.02 or more and Q max is remarkably decreased at 0.95 or more, and n = 0.02
This is because a material with extremely small loss can be provided in the range of up to 0.95. In the above composition formula, the range of the value of x is limited to 0.03 ≦ x ≦ 0.60 is 0.03
With the above, the sintering temperature is remarkably reduced, and the industrial cost is reduced, and the crystal structure of the sintered body can be controlled easily, while the industrial usefulness is increased. This is because when Q is 0.60 or more, Q max becomes a value smaller than x = 0, which causes an unfavorable effect on the magnetic core characteristics. In the above composition formula, the value of y is 0.0
The reason that 1 ≦ y ≦ 0.30 is limited is that if 0.01 or less, f
Qmax is 100 MHz or less, which is the subject of the present invention.
Is for no longer become a high-frequency magnetic core material that can be applied above 00MHz, in addition to the value of y is not observed effect of f Qmax improvement of Co added is less than 0.30, Q
This is because the decrease in max and the addition of relatively expensive Co do not produce any benefit, which is industrially disadvantageous.
【０００９】尚，次に述べる本発明の実施例において
は，ＮｉＯ，ＣｕＯ，α−Ｆｅ2 Ｏ3，Ｃｏ2 Ｏ3 を原
料として使用したフェライト焼結体のみについて述べて
いるが，必ずしもこれら酸化物に限定されるものでな
く，焼結体がスピネル型フェライトを構成するものであ
れば，本発明の範囲にあることは当業者であれば容易に
理解できる。また，Ｎｉ，Ｃｕ，Ｃｏ，Ｆｅを主成分と
して含有しているスピネル型フェライトであれば，他の
元素を含有していたとしても，本発明の範囲に含まれ
る。また，粉末の予備焼成及び成形体の焼結を大気中で
行なっているが，焼結における生成物がスピネル型フェ
ライトであれば，成形用粉末の製法が，予備焼成なし，
共沈法，水熱合成法，噴霧焙焼法等を適用しても，焼結
雰囲気が大気中に比べ，酸化性であっても還元性であっ
ても，本発明の範囲にある。また，本発明においては，
成形体の成形法についても特に限定されるものでない。In the examples of the present invention described below, only ferrite sintered bodies using NiO, CuO, α-Fe 2 O 3 and Co 2 O 3 as raw materials are described, but these oxides are not necessarily oxidized. Those skilled in the art can easily understand that the present invention is not limited to the above, and the sintered body is within the scope of the present invention as long as the sintered body constitutes a spinel type ferrite. Further, any spinel-type ferrite containing Ni, Cu, Co, Fe as a main component, even if it contains other elements, is included in the scope of the present invention. In addition, although pre-firing of the powder and sintering of the molded body are performed in the atmosphere, if the product of sintering is spinel type ferrite, the manufacturing method of the molding powder is
Even if a coprecipitation method, a hydrothermal synthesis method, a spray roasting method or the like is applied, the sintering atmosphere is within the scope of the present invention regardless of whether it is oxidizing or reducing as compared with the atmosphere. Further, in the present invention,
The method for molding the molded body is not particularly limited.
【００１０】[0010]
【実施例】以下，本発明の実施例について図面を参照し
て説明する。Embodiments of the present invention will be described below with reference to the drawings.
【００１１】（実施例１）化学組成比がＮｉ0.85・Ｃｕ
0.15・Ｆｅ(2-n) ・Ｃｏ0.05・Ｏ4 ，但し，ｎ＝０，
０．０５， ０．１， ０．２， ０．３， ０．４，
０．５， ０．６， ０．７， ０．８， ０．９，
１．０となるように，酸化鉄（α−Ｆｅ2 Ｏ3 ）と酸
化ニッケル（ＮｉＯ）と酸化第２銅（ＣｕＯ）と三二酸
化コバルト（Ｃｏ2 Ｏ3 ）とを原料として調製し，夫々
ボールミルにて２０時間湿式混合した。ここで使用した
粉末の粒度は全て０．５μｍ以下のものである。次に，
これら原料混合粉末を大気中，急熱，急冷にて，８００
℃で２時間予備焼成した後，この予備焼成粉末をボール
ミルにて３時間湿式粉末した。次に，これら粉砕粉末に
ポリビニルアルコール（以下，ＰＶＡと呼ぶ。）を１ｗ
ｔ％湿式混合し，成形用粉末とした。これら成形用粉末
を外径１０ｍｍ，内径２ｍｍの金型を用いて，高さ１０
ｍｍの成形体となるように成形圧２ｔｏｎ／ｃｍ2 で圧
縮成形した。次に，これら成形体を大気中，徐熱，炉冷
にて，９５０℃で４時間保持し焼結した。これら焼結体
は，外径約８．５ｍｍ，内径約１．７ｍｍ，及び高さ約
７．５ｍｍであった。次に，これら焼結体の磁芯特性
を，ＹＨＰ製アナライザー（品名４１９１Ａ）でコアキ
シャルフィクスチャを使用し，測定した。その結果を図
１に示す。図１で示すように，Ｑmax はｎ＝０．０２以
上で著しく向上し，０．９５以上で著しく低下すること
がわかる。また，μ100MHz及びｆQmaxは高周波用材料と
しては問題ない。したがって，ｎ＝０．０２〜０．９５
の範囲が極めて有用であるといえる。Example 1 The chemical composition ratio is Ni 0.85 · Cu.
0.15・ Fe (2-n)・ Co 0.05・ O 4 , where n = 0,
0.05, 0.1, 0.2, 0.3, 0.4,
0.5, 0.6, 0.7, 0.8, 0.9,
It was prepared by using iron oxide (α-Fe 2 O 3 ), nickel oxide (NiO), cupric oxide (CuO), and cobalt trioxide (Co 2 O 3 ) as raw materials so as to be 1.0, respectively. Wet mixing was performed for 20 hours in a ball mill. The particle sizes of the powders used here are all 0.5 μm or less. next,
These raw material mixed powders are heated to 800 in air and rapidly cooled.
After pre-firing at 2 ° C for 2 hours, the pre-firing powder was wet-milled for 3 hours in a ball mill. Next, 1 w of polyvinyl alcohol (hereinafter referred to as PVA) is added to these pulverized powders.
t% wet mixing was performed to obtain a molding powder. Using a mold with an outer diameter of 10 mm and an inner diameter of 2 mm, these molding powders were adjusted to a height of 10 mm.
It was compression-molded at a molding pressure of 2 ton / cm 2 so as to obtain a molded body of mm. Next, these compacts were sintered by holding them at 950 ° C. for 4 hours in the air with slow heating and furnace cooling. These sintered bodies had an outer diameter of about 8.5 mm, an inner diameter of about 1.7 mm, and a height of about 7.5 mm. Next, the magnetic core characteristics of these sintered bodies were measured with a YHP analyzer (product name 4191A) using a coaxial fixture. The result is shown in FIG. As shown in FIG. 1, it can be seen that Q max is remarkably improved when n = 0.02 or more and is remarkably lowered when it is 0.95 or more. Also, μ 100MHz and f Qmax are no problem for high frequency materials. Therefore, n = 0.02 to 0.95
It can be said that the range of is extremely useful.
【００１２】（実施例２）実施例１と同様にして，化学
組成比がＮｉ(1-x) ・Ｃｕx ・Ｆｅ1.5 ・Ｃｏ0. 05・Ｏ
4 ，但し，ｘ＝０， ０．０３， ０．１， ０．２，
０．３， ０．４， ０．５， ０．６， ０．７，
となるように，成形用粉末を作製し，成形体を得た。次
に，これら成形体を８５０℃〜１２００℃の範囲で焼結
し，焼結体密度及び磁芯特性を測定した。その結果を図
２に示す。図２に示した特性は，焼結体密度が５．４±
０．０５ｇ／ｃｍ3 の試料であり，Ｓ．Ｔ．（℃）はそ
の密度を得るための下限の焼結温度を表している。図２
から，ｘ＝０．０３以上では焼結温度が著しく降下して
おり，ｘ＝０．６以上ではＱmax がｘ＝０の場合よりも
低い値を示した。したがって，ｘ＝０．０３〜０．６の
範囲が有用な組成となる。[0012] (Example 2) In the same manner as in Example 1, the chemical composition ratio of Ni (1-x) · Cu x · Fe 1.5 · Co 0. 05 · O
4 , provided that x = 0, 0.03, 0.1, 0.2,
0.3, 0.4, 0.5, 0.6, 0.7,
The powder for molding was produced so as to obtain a compact. Next, these compacts were sintered in the range of 850 ° C. to 1200 ° C., and the sintered compact density and magnetic core characteristics were measured. The result is shown in FIG. The characteristics shown in Fig. 2 are that the sintered body density is 5.4 ±
0.05 g / cm 3 sample, S. T. (° C.) represents the lower limit of sintering temperature for obtaining the density. Figure 2
Therefore, the sintering temperature was remarkably lowered when x = 0.03 or more, and when x = 0.6 or more, the Q max was lower than that when x = 0. Therefore, the range of x = 0.03 to 0.6 is a useful composition.
【００１３】（実施例３）実施例１と同様にして，化学
組成比がＮｉ0.85・Ｃｕ0.15・Ｆｅ1.5 ・Ｃｏy・
Ｏ4 ，但し，ｙ＝０， ０．０１， ０．０３， ０．
０５， ０．１０，０．１５， ０．２０， ０．２
５， ０．３０， ０．３５となるように，成形用粉末
を作製し，成形体を得た。次に，これら成形体を９５０
℃で焼結した後，磁芯特性を測定した。その結果を図３
に示す。図３で示すように，ｙ＝０．０１以上でｆQmax
が１００ＭＨｚ以上を示す。一方，ｙ＝０．３以上では
ｆQmaxの向上は認められなくなるのに加え，Ｑmax は減
少するので有用でなくなる。したがって，ｙ＝０．０１
〜０．３０の範囲が有用な組成となる。[0013] (Example 3) In the same manner as in Example 1, the chemical composition ratio of Ni 0.85 · Cu 0.15 · Fe 1.5 · Co y ·
O 4 , provided that y = 0, 0.01, 0.03, 0.
05, 0.10, 0.15, 0.20, 0.2
Molding powder was prepared so as to obtain 5, 0.30, and 0.35 to obtain a molded body. Next, these molded bodies are 950
The magnetic core characteristics were measured after sintering at ℃. The result is shown in Figure 3.
Shown in. As shown in FIG. 3, when y = 0.01 or more, f Qmax
Indicates 100 MHz or more. On the other hand, when y = 0.3 or more, the improvement of f Qmax is not recognized, and Q max decreases, which is not useful. Therefore, y = 0.01
A range of ˜0.30 is a useful composition.
【００１４】[0014]
【発明の効果】以上の説明からわかるように，本発明で
は，Ｎｉ，Ｃｕ，Ｃｏ，Ｆｅの酸化物を主成分として含
有するスピネル型フェライト焼結体において，組成比を
Ｎｉ(1 -x) ・Ｃｕx ・Ｆｅ(2-n) ・Ｃｏy ・Ｏ4 ，（但
し，０．０２≦ｎ≦０．９５，０．０３≦ｘ≦０．６
０，０．０１≦ｙ≦０．３０）で表されるように構成す
ることにより，１００ＭＨｚ以上に適用できる磁芯材料
を工業的に有用に製造することができる。As can be seen from the above description, in the present invention, the composition ratio of the spinel type ferrite sintered body containing the oxides of Ni, Cu, Co and Fe as the main components is Ni (1 -x). · Cu x · Fe (2- n) · Co y · O 4, ( where, 0.02 ≦ n ≦ 0.95,0.03 ≦ x ≦ 0.6
0, 0.01 ≦ y ≦ 0.30), a magnetic core material applicable to 100 MHz or higher can be industrially usefully produced.
【図１】本発明の実施例１において，化学組成比Ｎｉ
0.85，Ｃｕ0.15・Ｆｅ(2-n) ・Ｃｏ0.05・Ｏ4 における
ｎと磁芯特性（μ100MHz，Ｑmax ，ｆQmax）の関係を示
した図である。FIG. 1 shows the chemical composition ratio Ni in Example 1 of the present invention.
0.85 is a diagram showing a relationship between Cu 0.15 · Fe (2-n ) · Co n and core characteristics in 0.05 · O 4 (μ 100MHz, Q max, f Qmax).
【図２】本発明の実施例２において，化学組成比Ｎｉ
(1-x) ・Ｃｕx ・Ｆｅ1.5 ・Ｃｏ0.05・Ｏ4 におけるｘ
と磁芯特性（μ100MHz，Ｑmax ，ｆQmax）及び焼結温度
（Ｓ．Ｔ．）の関係を示した図である。FIG. 2 shows the chemical composition ratio Ni in Example 2 of the present invention.
X in (1-x) , Cu x , Fe 1.5 , Co 0.05 , O 4
It is a figure showing the relation between magnetic core characteristics ( 100 MHz , Q max , f Qmax ) and sintering temperature (ST).
【図３】本発明の実施例３において，化学組成比Ｎｉ
0.85，Ｃｕ0.15・Ｆｅ1.5 ・Ｃｏy ・Ｏ4 におけるｙと
磁芯特性（μ100MHz，Ｑmax ，ｆQmax）の関係を示した
図である。FIG. 3 shows the chemical composition ratio Ni in Example 3 of the present invention.
0.85, Cu 0.15 · Fe 1.5 · Co y in y · O 4 and core properties (μ 100MHz, Q max, f Qmax) is a diagram showing the relationship between.
μ100MHz １００ＭＨｚにおける実効透磁率 Ｑmax 損失係数（ｔａｎδ）の逆数の最大値 ｆQmax Ｑmax を示した周波数 Ｓ．Ｔ． 焼結体密度５．４±０．０５ｇ／ｃｍ3 を
得るための下限の焼結温度μ 100 MHz Effective permeability at 100 MHz Q max Maximum value of reciprocal of loss coefficient (tan δ) f Qmax Q max frequency S. T. Lower limit of sintering temperature for obtaining sintered body density of 5.4 ± 0.05 g / cm 3
Claims (1)
分として含有するスピネル型フェライト焼結体におい
て，組成比が Ｎｉ(1-x) ・Ｃｕx ・Ｆｅ(2-n) ・Ｃｏy ・Ｏ4 （但し，０．０２≦ｎ≦０．９５，０．０３≦ｘ≦０．
６０，０．０１≦ｙ≦０．３０ ）で表わされることを
特徴とする高周波用酸化物磁性材料。1. A Ni, Cu, Co, in the spinel-type ferrite sintered body containing as a main component an oxide of Fe, the composition ratio of Ni (1-x) · Cu x · Fe (2-n) · Co y · O 4 (however, 0.02 ≦ n ≦ 0.95, 0.03 ≦ x ≦ 0.
60, 0.01 ≦ y ≦ 0.30), and a high-frequency oxide magnetic material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4141384A JPH05335135A (en) | 1992-06-02 | 1992-06-02 | Oxide magnetic material for high frequency |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4141384A JPH05335135A (en) | 1992-06-02 | 1992-06-02 | Oxide magnetic material for high frequency |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05335135A true JPH05335135A (en) | 1993-12-17 |
Family
ID=15290746
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4141384A Pending JPH05335135A (en) | 1992-06-02 | 1992-06-02 | Oxide magnetic material for high frequency |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05335135A (en) |
-
1992
- 1992-06-02 JP JP4141384A patent/JPH05335135A/en active Pending
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