JP2010111545A - Ferrite composition and inductor - Google Patents
Ferrite composition and inductor Download PDFInfo
- Publication number
- JP2010111545A JP2010111545A JP2008286380A JP2008286380A JP2010111545A JP 2010111545 A JP2010111545 A JP 2010111545A JP 2008286380 A JP2008286380 A JP 2008286380A JP 2008286380 A JP2008286380 A JP 2008286380A JP 2010111545 A JP2010111545 A JP 2010111545A
- Authority
- JP
- Japan
- Prior art keywords
- mol
- ferrite composition
- mhz
- terms
- mass
- 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.)
- Withdrawn
Links
Images
Landscapes
- Magnetic Ceramics (AREA)
- Soft Magnetic Materials (AREA)
Abstract
Description
本発明は、安価で環境影響が小さいＮｉフリーの高周波用磁性材料であって、特に1ＭＨｚを超える高周波帯域において損失の少ないＭｇＺｎ系フェライト組成物及びこのフェライト組成物からなるコアを用いたインダクタに関する。 The present invention relates to a Ni-free high-frequency magnetic material that is inexpensive and has a low environmental impact, and particularly relates to an MgZn-based ferrite composition with low loss in a high-frequency band exceeding 1 MHz and an inductor using a core made of this ferrite composition.
近年、電子、通信機器の小型化に伴い、それらの機器に使用される電子部品の小型化が求められている。各種電子機器の電子回路に使用されるインダクタもその要求に応え、小型化かつ高性能化が進められている。インダクタにはフェライト組成部からなるコアが用いられ、そのフェライト組成物には、小型化、高性能化のために損失係数が小さいことや温度係数が小さいことなどが要求される。このような特性を有するフェライト組成物としては、従来からＮｉＣｕＺｎフェライトが使用されてきた。 In recent years, with the miniaturization of electronic and communication devices, there has been a demand for miniaturization of electronic components used in such devices. Inductors used in electronic circuits of various electronic devices have also been reduced in size and performance in response to the demand. A core composed of a ferrite composition part is used for the inductor, and the ferrite composition is required to have a small loss coefficient and a small temperature coefficient for miniaturization and high performance. Conventionally, NiCuZn ferrite has been used as a ferrite composition having such characteristics.
しかしながら、このＮｉＣｕＺｎフェライトは高価なＮｉ原料を使用することから安価なフェライト材料を提供することができない。また、環境影響への配慮からＮｉＯを含まない、ＮｉＯフリーの電子部品が望まれている。 However, since this NiCuZn ferrite uses an expensive Ni raw material, an inexpensive ferrite material cannot be provided. In addition, NiO-free electronic components that do not contain NiO are desired in consideration of environmental impact.
他方、近年、情報量の増大や信号処理速度の上昇から、電子機器で取り扱う信号の周波数が高くなっており、使用周波数は高周波化の流れにある。 On the other hand, in recent years, the frequency of signals handled by electronic devices has increased due to an increase in the amount of information and an increase in signal processing speed, and the frequency used is increasing.
インダクタなどに使用されるＮｉＯフリーの安価なフェライト焼結体として、酸化鉄４７．０〜４９．６モル％、酸化亜鉛１８．０〜２７．０モル％、酸化マグネシウム１５．０〜２６．０モル％、酸化銅５．０〜９．０モル％からなる主成分組成で構成されるＭｇＣｕＺｎフェライト焼結体が知られている（特許文献１参照）。
しかしながら、上記のＭｇＣｕＺｎフェライト焼結体は、原料に酸化マグネシウム等を使用し、ＮｉＯフリーで安価ではあるものの、１００ｋＨｚ帯での使用を目的としており、高周波帯（例えば３ＭＨｚ）ですでにＱ値の低下が著しく、インダクタを含めた電子部品の使用周波数の高周波化に十分対応できない。また、電子部品用フェライト組成物は、実用的には温度特性として初透磁率μの２５℃を基準にしたときの１００℃での温度変化率Δμが±５０％以内であることが望ましい。
本発明は、１ＭＨｚを超える高周波帯域(〜５０ＭＨｚ)における損失を低減して十分なＱ値を有し、且つ温度特性の良好な、ＮｉＯフリーの安価で環境影響が小さいＭｇＺｎフェライト組成物およびこのフェライト組成物からなるコアを用いて製造されるインダクタを提供することを課題とする。
However, although the MgCuZn ferrite sintered body uses magnesium oxide as a raw material and is NiO-free and inexpensive, it is intended for use in the 100 kHz band and already has a Q value in the high frequency band (for example, 3 MHz). The decline is significant, and it is not possible to sufficiently cope with the increase in the operating frequency of electronic components including inductors. Moreover, it is desirable that the ferrite composition for electronic parts practically has a temperature change rate Δμ at 100 ° C. within ± 50% with reference to 25 ° C. of initial permeability μ as a temperature characteristic.
The present invention relates to a MgZ ferrite composition which has a sufficient Q value by reducing loss in a high frequency band (up to 50 MHz) exceeding 1 MHz, has a good temperature characteristic, is inexpensive and has a low environmental impact, and this ferrite. An object of the present invention is to provide an inductor manufactured using a core made of the composition.
本発明においては、上記の課題を解決するために、以下の手段を採用する。
（１）Ｆｅ２Ｏ３に換算して４５〜５０モル％の酸化鉄と、ＺｎＯに換算して２５モル％
以下（０を含まず）の酸化亜鉛と、ＭｇＯに換算して２５〜５０モル％の酸化マグ
ネシウムとからなる主成分１００質量部に対し、副成分としてＣｏＯに換算して０
．４〜３．２質量部の酸化コバルトを含有するフェライト組成物。
（２）焼結したフェライト組成物であって、３ＭＨｚでのＱ値が４０以上で、初透磁率μ
の２５℃を基準にしたときの１００℃での温度変化率Δμが±５０％以内である
（１）に記載のフェライト組成物。
（３）フェライト組成物からなる焼結体の結晶粒の平均粒径が３μｍ未満であり、該結晶
粒の粒度分布の標準偏差が０．５〜２の範囲にある（２）に記載のフェライト組成
物。
（４）（２）又は（３）に記載のフェライト組成物からなるコアを用いたインダクタ。
なお、本発明において、フェライト組成物とは、上記の成分を有する組成物であり、焼結後のものを指す。
In the present invention, the following means are adopted in order to solve the above problems.
(1) and iron oxide 45-50 mole percent terms of Fe 2 O 3, in terms of ZnO 25 mol%
The following (not including 0) zinc oxide and 100 parts by mass of the main component consisting of 25 to 50 mol% of magnesium oxide in terms of MgO, 0 in terms of CoO as a subsidiary component
. A ferrite composition containing 4 to 3.2 parts by mass of cobalt oxide.
(2) A sintered ferrite composition having a Q value of 40 or more at 3 MHz and an initial permeability μ
The ferrite composition according to (1), wherein the temperature change rate Δμ at 100 ° C. is within ± 50% with respect to 25 ° C.
(3) The ferrite according to (2), wherein the average grain size of the sintered body comprising the ferrite composition is less than 3 μm, and the standard deviation of the grain size distribution of the crystal grain is in the range of 0.5-2. Composition.
(4) An inductor using a core made of the ferrite composition according to (2) or (3).
In addition, in this invention, a ferrite composition is a composition which has said component, and points out the thing after sintering.
本発明によれば、ＮｉＯフリーであるので、安価で環境への負荷が少なく、しかも、１ＭＨｚを超える高周波帯域（〜５０ＭＨｚ）においても損失を抑えて十分に高いＱ値を有するＭｇＺｎフェライト組成物およびインダクタを提供することができる。 According to the present invention, since it is NiO-free, it is inexpensive, has a low environmental burden, and has a sufficiently high Q value while suppressing loss even in a high-frequency band (up to 50 MHz) exceeding 1 MHz. An inductor can be provided.
本発明のＭｇＺｎ系フェライト組成物は、主成分と副成分からなり、Ｆｅ２Ｏ３換算で４５〜５０モル％の酸化鉄と、ＭｇＯ換算で２５〜５０モル％の酸化マグネシウムと、酸化亜鉛の含有量がＺｎＯ換算で２５モル％以下（０を含まず）の酸化亜鉛とからなる主成分１００質量部に対し、副成分として、酸化コバルトをＣｏＯ換算で０．４〜３．２質量部含有することを特徴とする。 MgZn ferrite composition of the present invention comprises a main component and subcomponent, and 45 to 50 mol% of iron oxide calculated as Fe 2 O 3, and magnesium oxide 25 to 50 mol% in terms of MgO, of zinc oxide Cobalt oxide is contained in an amount of 0.4 to 3.2 parts by mass in terms of CoO as a subcomponent with respect to 100 parts by mass of the main component consisting of zinc oxide having a content of 25 mol% or less (excluding 0) in terms of ZnO. It is characterized by doing.
以下に、本発明にフェライト組成物の各成分の組成限定理由を説明する。 The reasons for limiting the composition of each component of the ferrite composition will be described below.
（主成分について）
・酸化鉄の含有量：Ｆｅ２Ｏ３換算で４５〜５０モル％
Ｆｅ２Ｏ３が４５モル％未満ではＭｇＯなどの偏析に伴う損失が増大し、高周波帯（例えば３ＭＨｚ）におけるＱ値が低下する。また、５０モル％を超えるとＦｅ２＋に伴う損失が発生し、やはり高周波帯におけるＱ値が低下する。
(About the main component)
- iron oxide content: Fe 2 O 3 in terms of 45 to 50 mol%
If Fe 2 O 3 is less than 45 mol%, loss due to segregation of MgO or the like increases, and the Q value in a high frequency band (eg, 3 MHz) decreases. Moreover, when it exceeds 50 mol%, the loss accompanying Fe2 + will generate | occur | produce and the Q value in a high frequency band will fall too.
・酸化亜鉛の含有量：ＺｎＯ換算で２５モル％以下（０を含まず）
ＺｎＯが２５モル％を超えるとキュリー点が著しく低下し、初透磁率μの２５℃を基準にしたときの１００℃での温度変化率Δμが大きくなる。
-Zinc oxide content: 25 mol% or less (excluding 0) in terms of ZnO
When ZnO exceeds 25 mol%, the Curie point is remarkably lowered, and the temperature change rate Δμ at 100 ° C. when the initial permeability μ is 25 ° C. is increased.
・酸化マグネシウムの含有量：ＭｇＯ換算で２５〜５０モル％
ＭｇＯが２５モル％未満では初透磁率μの２５℃を基準にしたときの１００℃での温度変化率Δμが大きくなり、５０モル％を超えると過剰なＭｇによって損失が増大し、高周波帯（例えば３ＭＨｚ）におけるＱ値をはじめとする磁気特性が低下する。
Magnesium oxide content: 25-50 mol% in terms of MgO
If the MgO content is less than 25 mol%, the temperature change rate Δμ at 100 ° C. based on the initial permeability μ of 25 ° C. becomes large. If it exceeds 50 mol%, the loss increases due to excess Mg, and the high frequency band ( For example, the magnetic characteristics including the Q value at 3 MHz) deteriorate.
（副成分について）
・酸化コバルト：ＣｏＯ換算で０．４〜３．２質量部
本発明のフェライト組成物は、上記の主成分１００質量部に対して、副成分として酸化コバルトを０．４〜３．２質量部含有する。
(About secondary ingredients)
Cobalt oxide: 0.4 to 3.2 parts by mass in terms of CoO The ferrite composition of the present invention has 0.4 to 3.2 parts by mass of cobalt oxide as a subcomponent with respect to 100 parts by mass of the main component. contains.
ＣｏＯは負の結晶磁気異方性を持つため、ＭｇＺｎ系フェライトに含有させるとＣｏＯが固溶し、結晶粒内の結晶磁気異方性がほぼゼロになり、高周波帯の損失の低減、すなわち高周波帯（例えば３ＭＨｚ）におけるＱ値の向上に有効に寄与する。ただし、その含有量が主成分１００質量部に対して、０．４質量部未満ではその効果が小さく高周波帯におけるＱ値が低下し、含有量が３．２質量部を超えると初透磁率μの２５℃を基準にしたときの１００℃での温度変化率Δμが大きくなるため、０．４〜３．２質量部とした。 Since CoO has negative crystal magnetic anisotropy, when it is contained in MgZn ferrite, CoO is dissolved, crystal magnetic anisotropy in the crystal grains becomes almost zero, and the loss in the high frequency band is reduced, that is, the high frequency This effectively contributes to the improvement of the Q value in the band (eg, 3 MHz). However, when the content is less than 0.4 parts by mass with respect to 100 parts by mass of the main component, the effect is small and the Q value in the high frequency band is lowered, and when the content exceeds 3.2 parts by mass, the initial permeability μ Since the temperature change rate Δμ at 100 ° C. with respect to 25 ° C. was increased, it was set to 0.4 to 3.2 parts by mass.
ＣｏＯ含有によるＱ値向上効果として、ＣｏＯ無含有時Ｑ＝１８（ａｔ３ＭＨｚ）である組成の試料１００質量部に対して、ＣｏＯを０．４質量部含有させることでＱ＝５０に、さらにＣｏＯを３．２質量部含有させることでＱ＝９０（ａｔ３０ＭＨｚ）までそれぞれ向上できることが確認でき、本発明のフェライト組成物が高周波インダクタ用として数十ＭＨｚ帯域でも十分な特性を有していることが見いだされた。 As an effect of improving the Q value by containing CoO, by adding 0.4 parts by mass of CoO to 100 parts by mass of a sample having a composition of Q = 18 (at 3 MHz) when no CoO is contained, Q = 50, and further CoO By adding 3.2 parts by mass, it can be confirmed that each can be improved up to Q = 90 (at 30 MHz), and the ferrite composition of the present invention has been found to have sufficient characteristics even in the tens of MHz band for high frequency inductors. It was.
本発明のフェライト組成物は焼結処理等が施されて、コイル等のコアが製造されるが、以下に本発明のフェライト組成物の製造方法について説明する。 The ferrite composition of the present invention is subjected to a sintering treatment or the like to produce a core such as a coil. The method for producing the ferrite composition of the present invention will be described below.
酸化鉄、酸化亜鉛、酸化マグネシウムおよび酸化コバルトを所定量含有する原材料粉末をボールミル等で混合し、ついで、この混合粉末を熱処理してBET比表面積が１〜７ｍ２／ｇなる仮焼粉を得、この仮焼粉をボールミル等で粉砕して解砕し、この解砕粉にバインダーを加えて造粒する。仮焼温度は６５０〜９５０℃とすることが好ましい。バインダーとしては、ポリビニルアルコール（ＰＶＡ）やポリビニルブチラール樹脂やアクリル酸ポリマー等を使用することができる。
次いで、このフェライト造粒粉を所望のコア形状に形成し、この成形体を焼成炉中で、昇温・冷却速度や焼成温度、保持時間等を所定の範囲に調整して、焼成し焼結体を得る。
Raw material powder containing a predetermined amount of iron oxide, zinc oxide, magnesium oxide and cobalt oxide is mixed with a ball mill or the like, and then the mixed powder is heat-treated to obtain a calcined powder having a BET specific surface area of 1 to 7 m 2 / g. The calcined powder is pulverized by a ball mill or the like and crushed, and a binder is added to the crushed powder and granulated. The calcination temperature is preferably 650 to 950 ° C. As the binder, polyvinyl alcohol (PVA), polyvinyl butyral resin, acrylic acid polymer, or the like can be used.
Next, this ferrite granulated powder is formed into a desired core shape, and this molded body is fired and sintered in a firing furnace by adjusting the temperature rise / cooling rate, firing temperature, holding time, etc. to a predetermined range. Get the body.
本発明では、焼結後の焼結体の結晶粒を、平均粒径が３μｍ未満とし、且つ粒度分布の標準偏差が０．５〜２の範囲にある均一で小径な結晶粒になるよう制御することが好ましい。
これは、焼結後のフェライト組成物（フェライト焼結体）においては、その粒径が単磁区粒子径となり単磁区構造となることで高周波帯での損失を低減できるためである。
以上の結晶粒を有する焼結体を達成する上で、焼成条件は、昇温・冷却速度３００℃／ｈｒ〜２０００℃／ｈｒで、焼成温度１１００℃〜１２００℃で保持時間２時間以内であることが望ましく、特に焼成温度は１１００℃未満では十分に緻密化することができず、１２００℃を超えると酸素欠陥による比抵抗の低下が生じるため、上記温度範囲が最適である。
In the present invention, the crystal grains of the sintered body after sintering are controlled to be uniform and small-diameter grains having an average grain size of less than 3 μm and a standard deviation of the grain size distribution in the range of 0.5 to 2. It is preferable to do.
This is because the sintered ferrite composition (ferrite sintered body) has a single-domain particle size and a single-domain structure to reduce the loss in the high-frequency band.
In achieving the sintered body having the above crystal grains, the firing conditions are a heating / cooling rate of 300 ° C./hr to 2000 ° C./hr, a firing temperature of 1100 ° C. to 1200 ° C., and a holding time of 2 hours or less. In particular, if the firing temperature is less than 1100 ° C., sufficient densification cannot be achieved, and if it exceeds 1200 ° C., the specific resistance decreases due to oxygen defects, so the above temperature range is optimal.
図１は後述する本発明例１のフェライト焼結体の自由表面をＳＥＭ（走査型電子顕微鏡、日立製S4300SE/N)で５０００倍で撮影した写真に基づいて作成されている。
本発明のフェライト焼結体の結晶粒は、例えば図１のようになっており、平均粒径が３μｍ未満であり、且つ粒度分布の標準偏差が０．５〜２の範囲にあることを特徴とする。
FIG. 1 is created based on a photograph of a free surface of a ferrite sintered body of Example 1 of the present invention, which will be described later, taken with a SEM (scanning electron microscope, Hitachi S4300SE / N) at a magnification of 5000 times.
The crystal grains of the ferrite sintered body of the present invention are, for example, as shown in FIG. 1, and the average grain size is less than 3 μm, and the standard deviation of the grain size distribution is in the range of 0.5 to 2. And
造粒粉を所望の形状にして焼結して、本発明のフェライト組成物からなるインダクタのコアを製造する場合を説明したが、造粒粉から作製された本発明のフェライト組成物からなる磁性体層と内部導体とを積層して各種の高周波対応のインダクタを製造することもできる。
以下、実施例により、本発明をさらに説明する。
The case where the core of the inductor made of the ferrite composition of the present invention is manufactured by sintering the granulated powder into a desired shape has been explained, but the magnetic made of the ferrite composition of the present invention made from the granulated powder was explained. Various high frequency compatible inductors can be manufactured by laminating the body layer and the inner conductor.
The following examples further illustrate the present invention.
実施例として、表１に示される５種の試料を製造した。比較例１は組成がＦｅ２Ｏ３：４８．８モル％、ＭｇＯ：２５．９モル％、ＺｎＯ：１８．３モル％、ＣｕＯ：６．９モル％、ＭｎＯ：０．１モル％である従来材である（特許文献１における実施例６参照）。そして、比較例２、本発明例１、本発明例２及び比較例３は、Ｆｅ２Ｏ３のモル％及びＭｇ／Ｚｎ比が比較例１と同じかほぼ同じであるＦｅ２Ｏ３：４８．８モル％、ＭｇＯ：３０．１モル％、ＺｎＯ：２１．１モル％からなる主成分１００質量部に対して副成分としてＣｏＯの含有量がそれぞれ０質量部、０．４質量部、３．２質量部、３．６質量部含有するものである。 As examples, five types of samples shown in Table 1 were manufactured. Comparative Example 1 has a composition of Fe 2 O 3 : 48.8 mol%, MgO: 25.9 mol%, ZnO: 18.3 mol%, CuO: 6.9 mol%, MnO: 0.1 mol% It is a conventional material (see Example 6 in Patent Document 1). In Comparative Example 2, Invention Example 1, Invention Example 2 and Comparative Example 3, the Fe 2 O 3 mole percentage and the Mg / Zn ratio are the same as or substantially the same as Comparative Example 1 Fe 2 O 3 : 48 The content of CoO as an auxiliary component is 0 parts by mass, 0.4 parts by mass, 3 parts by mass with respect to 100 parts by mass of the main component consisting of 0.8 mol%, MgO: 30.1 mol%, and ZnO: 21.1 mol%, respectively. .2 parts by mass and 3.6 parts by mass are contained.
これら５種の組成物について、それぞれ下記表１に示す用に、各成分を所定量配合した後にボールミルで湿式混合し、得られた混合粉を８５０℃−２時間保持にて仮焼し合成粉を作製した。次いで、この合成粉をボールミルで湿式解砕したのち、得られた解砕粉にバインダーとしてＰＶＡを添加して造粒粉を作製し、この造粒粉をつかってφ１５ｍｍのトロイダル形状の成型体を作製した。
更に、この成型体を、１１００℃−２時間保持の焼成条件でそれぞれ焼成を行ない、トロイダル形状の焼結体からなる試料を得た。得られた各焼結体からなる資料についてＸＲＦ（ケイ光Ｘ線分析）を用いて組成比を確認した結果、それぞれ配合時に各酸化物に換算した組成比と等しいものであることを確認した。
About these five types of compositions, as shown in Table 1 below, each component is blended in a predetermined amount, and then wet-mixed with a ball mill, and the resulting mixed powder is calcined at 850 ° C. for 2 hours to obtain a synthetic powder. Was made. Next, this synthetic powder is wet crushed with a ball mill, and then PVA is added as a binder to the obtained crushed powder to produce a granulated powder. Using this granulated powder, a toroidal shaped molded product having a diameter of 15 mm is obtained. Produced.
Furthermore, this molded body was fired under firing conditions of 1100 ° C. for 2 hours, and a sample composed of a toroidal shaped sintered body was obtained. As a result of confirming the composition ratio using XRF (fluorescence X-ray analysis) for the obtained material composed of each sintered body, it was confirmed that it was the same as the composition ratio converted into each oxide at the time of blending.
得られた各試料について、インピーダンスアナライザ（Agilent製 4991A）を用いて、透磁率の実数部と虚数部であるμ’とμ”を１ＭＨｚ〜３ＧＨｚの周波数帯で測定し、３ＭＨｚ、３０ＭＨｚのそれぞれにおけるμ’とμ”の値からＱ値を計算した。
Ｑ＝μ’／μ”
また、初透磁率μの温度変化率については、２５℃から１００℃にかけてのμの変化率Δμを次式より求めた。
Δμ［％］＝[〔（μ100℃）−（μ25℃）〕／（μ25℃）]×１００
ここで、μ100℃、μ25℃はそれぞれ１００℃、２５℃での初透磁率である。
更に、トロイダル形状の焼結体の結晶粒の平均粒径及び該結晶粒の粒度分布の評価としては、前記焼結体の自由表面をＳＥＭ（走査型電子顕微鏡、日立製 S4300SE/N）で撮影した写真について各試料３００個のフェライト粒子を選び出して画像解析を行い、平均粒径として円相当径の平均値を求め、また粒度分布の標準偏差として前記円相当径の標準偏差を求めた。尚、円相当径とは、面積が等しい真円の直径に換算した値をいう。
For each of the obtained samples, using an impedance analyzer (Agilent 4991A), the real part and the imaginary part of the magnetic permeability μ ′ and μ ″ are measured in the frequency band of 1 MHz to 3 GHz, and each of them is 3 MHz and 30 MHz. The Q value was calculated from the values of μ ′ and μ ″.
Q = μ '/ μ "
As for the temperature change rate of the initial permeability μ, the change rate Δμ of μ from 25 ° C. to 100 ° C. was obtained from the following equation.
Δμ [%] = [[(μ100 ° C.) − (Μ25 ° C.)] / (Μ25 ° C.)] × 100
Here, μ100 ° C. and μ25 ° C. are initial magnetic permeability at 100 ° C. and 25 ° C., respectively.
Furthermore, as an evaluation of the average grain size and grain size distribution of the toroidal sintered body, the free surface of the sintered body was photographed with SEM (scanning electron microscope, Hitachi S4300SE / N). From the photograph, 300 ferrite particles of each sample were selected and image analysis was performed to obtain an average value of equivalent circle diameter as an average particle diameter, and a standard deviation of equivalent circle diameter as a standard deviation of particle size distribution. The equivalent circle diameter refers to a value converted to the diameter of a perfect circle having the same area.
以上のようにして作製した試料の評価結果を表１に示す。 Table 1 shows the evaluation results of the samples prepared as described above.
従来材の比較例１は、２５℃から１００℃にかけての初透磁率μの変化率Δμは比較的小さく、満足すべき範囲であるが、３ＭＨｚ、３０ＭＨｚでのＱ値がそれぞれ３、０．８であり、高周波帯域でのＱ値の低下が著しく、高周波用のインダクタ用の磁性材料として不適である。 In Comparative Example 1 of the conventional material, the change rate Δμ of the initial permeability μ from 25 ° C. to 100 ° C. is relatively small and is in a satisfactory range, but the Q values at 3 MHz and 30 MHz are 3, 0.8 respectively. Therefore, the Q value is significantly lowered in the high frequency band, and is not suitable as a magnetic material for high frequency inductors.
これに対して、ＣｏＯをそれぞれ０．４質量部、３．２質量部含有する本発明例１及び本発明例２は、２５℃から１００℃にかけての初透磁率μの変化率Δμは従来材の比較例１と遜色なく、しかも、Ｑ値についても、３ＭＨｚでそれぞれ５０、２１０、３０ＭＨｚでそれぞれ８、９０であり、高周波帯域で使用されるインダクタの磁性材料として満足すべきものである。 On the other hand, the present invention example 1 and the present invention example 2 containing 0.4 parts by mass and 3.2 parts by mass of CoO, respectively, show the change rate Δμ of the initial permeability μ from 25 ° C. to 100 ° C. The Q value is 50, 210, and 30 MHz at 3 MHz and 8 and 90, respectively, and is satisfactory as a magnetic material for an inductor used in a high frequency band.
ＣｏＯを含有しない比較例２は、上記のΔμは比較例１や本発明例１、２と遜色はないが、３ＭＨｚ、３０ＭＨｚでのＱ値が本発明例１、２と比較して著しく低い。また、ＣｏＯを本発明で規定する範囲を超えて３．６質量部含有する比較例５は、３ＭＨｚ、３０ＭＨｚでのＱ値は満足すべきものであるが、２５℃から１００℃にかけての初透磁率μの変化率Δμが著しく大きいので、高周波用のインダクタ用のフェライト組成物としては不適である。 In Comparative Example 2 containing no CoO, the above Δμ is not inferior to Comparative Example 1 and Invention Examples 1 and 2, but the Q value at 3 MHz and 30 MHz is significantly lower than that of Invention Examples 1 and 2. Further, Comparative Example 5 containing 3.6 parts by mass of CoO beyond the range defined in the present invention should satisfy the Q value at 3 MHz and 30 MHz, but the initial permeability from 25 ° C. to 100 ° C. Since the change rate Δμ of μ is remarkably large, it is not suitable as a ferrite composition for high frequency inductors.
さらに、主成分の各成分と副成分の含有率が本発明例１、２と異なる本発明例３〜１７および比較例４〜７を表２に示す。 Furthermore, Table 2 shows Invention Examples 3 to 17 and Comparative Examples 4 to 7 in which the content ratios of each component of the main component and subcomponents are different from those of Invention Examples 1 and 2.
比較例４は、主成分のＦｅ２Ｏ３量が４４ｍｏｌ％で本発明の組成範囲外であり、３ＭＨｚにおけるＱ値が４０未満である。比較例５は、主成分のＦｅ２Ｏ３量が５１ｍｏｌ％で本発明の組成範囲外であり、３ＭＨｚにおけるＱ値が４０未満である。比較例６は、ＭｇＯが２０ｍｏｌ％、ＺｎＯが３０ｍｏｌ％で、それぞれ本発明の組成範囲外であり、初透磁率μの２５℃を基準にしたときの１００℃の温度変化率Δμが５０％を超えている。また、比較例７は、ＭｇＯが５４ｍｏｌ％で本発明の組成範囲外であり、３ＭＨｚにおけるＱ値が４０未満である。 In Comparative Example 4, the amount of the main component Fe 2 O 3 is 44 mol%, which is outside the composition range of the present invention, and the Q value at 3 MHz is less than 40. In Comparative Example 5, the amount of the main component Fe 2 O 3 is 51 mol%, which is outside the composition range of the present invention, and the Q value at 3 MHz is less than 40. In Comparative Example 6, MgO is 20 mol% and ZnO is 30 mol%, which are outside the composition range of the present invention, and the temperature change rate Δμ at 100 ° C. is 50% when the initial permeability μ is 25 ° C. Over. In Comparative Example 7, MgO is 54 mol%, which is outside the composition range of the present invention, and the Q value at 3 MHz is less than 40.
本発明例３〜１７は、いずれも主成分及ぶ副成分が本発明の組成範囲の規定を満たすものであり、３ＭＨｚでのＱ値が４０以上であり、２５℃から１００℃にかけての初透磁率μの変化率Δμが５０％以内である。 In Examples 3 to 17 of the present invention, all the main components and subcomponents satisfy the definition of the composition range of the present invention, the Q value at 3 MHz is 40 or more, and the initial permeability from 25 ° C. to 100 ° C. The rate of change Δμ of μ is within 50%.
本発明例３と本発明例１０は、ＣｏＯ量がそれぞれ０．４質量部、１．６質量部であり、この点で両者は異なるが、３ＭＨｚでのＱ値は、本発明例３では９５、本発明例１０では１７７である。同様に、本発明例６と本発明例１２はＣｏＯ量がそれぞれ３．２質量部、１．６質量部で異なり、３ＭＨｚでのＱ値は本発明例６では１２３、本発明例１２では４１である。 Inventive Example 3 and Inventive Example 10 have CoO contents of 0.4 parts by mass and 1.6 parts by mass, respectively, and both differ in this respect, but the Q value at 3 MHz is 95 in Inventive Example 3. In the inventive example 10, it is 177. Similarly, the present invention example 6 and the present invention example 12 differ in the amount of CoO at 3.2 parts by mass and 1.6 parts by mass, respectively, and the Q value at 3 MHz is 123 in the present invention example 6 and 41 in the present invention example 12. It is.
本発明によれば、酸化鉄、酸化亜鉛および酸化マグネシウムとからなる主成分に副成分として酸化コバルトを含有させて、組成を調整することにより、高周波帯（＞１ＭＨｚ）における損失低減効果（＝Ｑ向上効果）と良好な温度特性を有するフェライト組成物が得られることが確認できた。 According to the present invention, the loss reduction effect (= Q in the high frequency band (> 1 MHz) is obtained by adding cobalt oxide as a subsidiary component to the main component composed of iron oxide, zinc oxide and magnesium oxide and adjusting the composition. It was confirmed that a ferrite composition having an improvement effect) and good temperature characteristics was obtained.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008286380A JP2010111545A (en) | 2008-11-07 | 2008-11-07 | Ferrite composition and inductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008286380A JP2010111545A (en) | 2008-11-07 | 2008-11-07 | Ferrite composition and inductor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2010111545A true JP2010111545A (en) | 2010-05-20 |
Family
ID=42300419
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2008286380A Withdrawn JP2010111545A (en) | 2008-11-07 | 2008-11-07 | Ferrite composition and inductor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2010111545A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104505225A (en) * | 2014-12-11 | 2015-04-08 | 安徽龙磁科技股份有限公司 | Stable ferrite core material |
| CN104557000A (en) * | 2015-01-15 | 2015-04-29 | 安徽龙磁科技股份有限公司 | Anti-interference ferrite magnetic core material |
| CN114195497A (en) * | 2021-10-18 | 2022-03-18 | 江西瑞吉磁电子科技有限公司 | High-frequency and high-Curie-temperature magnetic core material and preparation method thereof |
-
2008
- 2008-11-07 JP JP2008286380A patent/JP2010111545A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104505225A (en) * | 2014-12-11 | 2015-04-08 | 安徽龙磁科技股份有限公司 | Stable ferrite core material |
| CN104557000A (en) * | 2015-01-15 | 2015-04-29 | 安徽龙磁科技股份有限公司 | Anti-interference ferrite magnetic core material |
| CN114195497A (en) * | 2021-10-18 | 2022-03-18 | 江西瑞吉磁电子科技有限公司 | High-frequency and high-Curie-temperature magnetic core material and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3108803B2 (en) | Mn-Zn ferrite | |
| JP2006306693A (en) | Ferrite sintered body and method for manufacturing same | |
| JP4523430B2 (en) | High saturation magnetic flux density Mn-Zn-Ni ferrite | |
| JP4826093B2 (en) | Ferrite, electronic component and manufacturing method thereof | |
| JP3907642B2 (en) | Ferrite material and method for producing ferrite material | |
| JP2010111545A (en) | Ferrite composition and inductor | |
| JP5734078B2 (en) | Ferrite sintered body and noise filter including the same | |
| JP6558505B2 (en) | Ni-based ferrite sintered body, coil component, and manufacturing method of Ni-based ferrite sintered body | |
| JP4813025B2 (en) | High saturation magnetic flux density Mn-Zn-Ni ferrite | |
| JP5836887B2 (en) | Ferrite sintered body and noise filter including the same | |
| JP6730546B1 (en) | MnCoZn ferrite and method for producing the same | |
| JP4031886B2 (en) | Method for producing Ni-Zn ferrite | |
| JP6967418B2 (en) | Magnetic materials and laminated chip parts | |
| JP3446082B2 (en) | Mn-Zn ferrite and method for producing the same | |
| JP5882811B2 (en) | Ferrite sintered body and pulse transformer core comprising the same | |
| JP2010215453A (en) | NiCuZn FERRITE | |
| JP2003221232A (en) | Ferrite material and its production method | |
| JPWO2020189035A1 (en) | MnCoZn-based ferrite and its manufacturing method | |
| JP2007169115A (en) | Ferrite sintered compact | |
| JP5660698B2 (en) | Magnetic oxide material | |
| JP3856722B2 (en) | Manufacturing method of spinel type ferrite core | |
| JP2007031204A (en) | W-type ferrite magnet | |
| JP2008184364A (en) | Oxide magnetic material | |
| JP7221751B2 (en) | Magnetic materials and laminated chip components | |
| WO2020158519A1 (en) | Ferrite composite powder, method for producing ferrite molded body, method for producing ferrite sintered body, molded body, and sintered body |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20120110 |