JPH04278502A - Oxide magnetic material - Google Patents
Oxide magnetic materialInfo
- Publication number
- JPH04278502A JPH04278502A JP3065625A JP6562591A JPH04278502A JP H04278502 A JPH04278502 A JP H04278502A JP 3065625 A JP3065625 A JP 3065625A JP 6562591 A JP6562591 A JP 6562591A JP H04278502 A JPH04278502 A JP H04278502A
- Authority
- JP
- Japan
- Prior art keywords
- oxide magnetic
- magnetic material
- weight
- pbo
- talc
- 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.)
- Granted
Links
- 239000000696 magnetic material Substances 0.000 title claims abstract description 35
- 239000000454 talc Substances 0.000 claims abstract description 25
- 229910052623 talc Inorganic materials 0.000 claims abstract description 25
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 17
- 229910052681 coesite Inorganic materials 0.000 claims description 10
- 229910052906 cristobalite Inorganic materials 0.000 claims description 10
- 239000002994 raw material Substances 0.000 claims description 10
- 239000000377 silicon dioxide Substances 0.000 claims description 10
- 235000012239 silicon dioxide Nutrition 0.000 claims description 10
- 229910052682 stishovite Inorganic materials 0.000 claims description 10
- 229910052905 tridymite Inorganic materials 0.000 claims description 10
- 230000005291 magnetic effect Effects 0.000 claims description 9
- -1 SiO2 compound Chemical class 0.000 claims description 4
- 229910000859 α-Fe Inorganic materials 0.000 abstract description 6
- 229910017518 Cu Zn Inorganic materials 0.000 abstract 1
- 229910017752 Cu-Zn Inorganic materials 0.000 abstract 1
- 229910017943 Cu—Zn Inorganic materials 0.000 abstract 1
- 238000013001 point bending Methods 0.000 description 11
- 238000005452 bending Methods 0.000 description 5
- 150000001875 compounds Chemical class 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 3
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 3
- 229910020615 PbO—SiO2 Inorganic materials 0.000 description 2
- 230000005294 ferromagnetic effect Effects 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Soft Magnetic Materials (AREA)
Abstract
Description
［発明の目的］ [Purpose of the invention]
【０００１】0001
【産業上の利用分野】本発明は、酸化物磁性材料に関し
、より詳しくは、例えばドラム型コアの磁心等に適用し
て好適な機械的強度の増大を図った酸化物磁性材料に関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxide magnetic material, and more particularly to an oxide magnetic material which can be applied to, for example, a magnetic core of a drum-shaped core and has a suitable increase in mechanical strength.
【０００２】0002
【従来の技術】酸化物磁性材料の主流を占めるフェライ
トは、一般に機械的強度が弱く、かつ、もろいので、こ
のようなフェライトを例えばドラム型コアとして用いた
場合、その加工工程で破壊してしまったり、ワイヤの巻
線工程で損傷したり割れたりすることが多い。[Prior Art] Ferrite, which is the mainstay of oxide magnetic materials, generally has weak mechanical strength and is brittle, so if such ferrite is used, for example, as a drum-shaped core, it may break during the processing process. They are often damaged or cracked during the wire winding process.
【０００３】かかる観点から、本願出願人は、先に特公
昭４８−４０９５４号において機械的強度の向上を図っ
た強磁性フェライトを提案している。From this viewpoint, the applicant of the present application previously proposed a ferromagnetic ferrite with improved mechanical strength in Japanese Patent Publication No. 48-40954.
【０００４】0004
【発明が解決しようとする課題】しかしながら、同公報
に開示した強磁性フェライトは、フェライトを原料とし
、この原料にＰｂＯ０．２乃至３重量％、タルク０．２
乃至３重量％を含有させたものであり、その機械的強度
は７乃至１２Ｋｇ／ｍｍ２ 程度である。[Problems to be Solved by the Invention] However, the ferromagnetic ferrite disclosed in the publication uses ferrite as a raw material, and this raw material contains 0.2 to 3% by weight of PbO and 0.2% of talc.
It contains 3 to 3% by weight, and its mechanical strength is about 7 to 12 kg/mm2.
【０００５】このため、機械的強度が十分でなく、特に
近年におけるドラム型コア等の小型化、薄型化に伴う機
械的強度の向上の要請に対処できないという問題があっ
た。[0005] For this reason, there is a problem in that the mechanical strength is not sufficient and it is not possible to meet the demand for improved mechanical strength, especially as drum-shaped cores and the like have become smaller and thinner in recent years.
【０００６】そこで、本発明は材料組成を改良し、従来
例よりも機械的強度を大幅に改良した酸化物磁性材料を
提供することを目的とするものである。SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an oxide magnetic material with improved material composition and significantly improved mechanical strength compared to conventional examples.
【０００７】［発明の構成］[Configuration of the invention]
【０００８】[0008]
【課題を解決するための手段】請求項１記載の酸化物磁
性材料は、酸化物磁性原料に、ＰｂＯ３．１乃至３０重
量％及びＳｉＯ２ ０．１乃至３０重量％を含有したも
のである。The oxide magnetic material according to claim 1 contains 3.1 to 30% by weight of PbO and 0.1 to 30% by weight of SiO2 in the oxide magnetic raw material.
【０００９】請求項２記載の酸化物磁性材料は、酸化物
磁性原料に、ＰｂＯ３．１乃至３０重量％及びタルク３
．１乃至３０重量％を含有したものである。The oxide magnetic material according to claim 2 contains 3.1 to 30% by weight of PbO and 3.0% by weight of talc in the oxide magnetic raw material.
．． It contains 1 to 30% by weight.
【００１０】請求項３記載の酸化物磁性材料は、酸化物
磁性原料にＰｂＯ３．１乃至３０重量％及びタルクを除
くＳｉＯ２ 化合物０．１乃至３０重量％を含有したも
のである。The oxide magnetic material according to claim 3 contains 3.1 to 30% by weight of PbO and 0.1 to 30% by weight of an SiO2 compound excluding talc in the oxide magnetic raw material.
【００１１】[0011]
【作用】請求項１記載の酸化物磁性材料においては、３
．１乃至３０重量％のＰｂＯ及び０．１乃至３０重量％
のＳｉＯ２ が、酸化物磁性原料の焼成段階でＰｂＯ−
ＳｉＯ２ 化合物として主に酸化物磁性原料の結晶粒界
に存在する状態となって酸化物磁性材料と２相構造を形
成する。[Function] In the oxide magnetic material according to claim 1, 3
．． 1-30% by weight PbO and 0.1-30% by weight
of SiO2 is converted into PbO- during the firing stage of the oxide magnetic raw material.
As a SiO2 compound, it mainly exists in the grain boundaries of the oxide magnetic material and forms a two-phase structure with the oxide magnetic material.
【００１２】そして、この場合、酸化物磁性材料の熱膨
脹係数が１０×１０−６／℃、ＰｂＯ−ＳｉＯ２ 化合
物の熱膨脹係数が７×１０−６／℃と差があるため、焼
成後の冷却過程で粒界中のＰｂＯ−ＳｉＯ２ 化合物に
圧縮応力が蓄積され、この結果、酸化物磁性材料に引張
り力が作用する際の強度が大きくなる。[0012] In this case, since there is a difference in the coefficient of thermal expansion of the oxide magnetic material from 10 x 10-6/°C to that of the PbO-SiO2 compound to 7 x 10-6/°C, the cooling process after firing is Compressive stress is accumulated in the PbO-SiO2 compound in the grain boundaries, and as a result, the strength when tensile force is applied to the oxide magnetic material increases.
【００１３】請求項２記載の酸化物磁性材料においては
、３．１乃至３０重量％のＰｂＯと、３．１乃至３０重
量％のタルク中のＳｉ成分とが、上述した場合と同様Ｐ
ｂＯ−Ｓｉ化合物となって結晶粒界に存在するものと考
えられ、これにより上述した場合と同様な作用を発揮し
、この酸化物磁性材料の機械的強度が大きくなる。In the oxide magnetic material according to claim 2, 3.1 to 30% by weight of PbO and 3.1 to 30% by weight of the Si component in the talc are P as in the above case.
It is thought that it becomes a bO-Si compound and exists at the grain boundaries, thereby exerting the same effect as in the case described above, and increasing the mechanical strength of this oxide magnetic material.
【００１４】請求項３記載の酸化物磁性材料においては
、上述した場合と同様、ＰｂＯとタルクを除くＳｉＯ２
化合物中のＳｉとがＰｂＯ−Ｓｉ化合物となって結晶
粒界に存在するものと考えられ、これにより、この酸化
物磁性材料の機械的強度が大きくなる。In the oxide magnetic material according to claim 3, as in the case described above, SiO2 excluding PbO and talc is used.
It is thought that Si in the compound forms a PbO-Si compound and exists at the grain boundaries, thereby increasing the mechanical strength of this oxide magnetic material.
【００１５】[0015]
【実施例】以下に本発明の実施例を詳細に説明する。EXAMPLES Examples of the present invention will be described in detail below.
【００１６】例１
Ｆｅ２ Ｏ３ ４７モル％、ＮｉＯ２７モル％、ＣｕＯ
４モル％、ＺｎＯ１７モル％、ＭｎＯ５．０モル％の組
成からなる酸化物磁性原料としてのフェライトに、Ｐｂ
Ｏ４乃至６．５重量（Ｗｔ）％及びタルク４乃至５．５
重量％を添加し、１０６０℃の温度条件で焼成して酸化
物磁性材料を得た。Example 1 47 mol% Fe2O3, 27 mol% NiO, CuO
Pb
O4 to 6.5% by weight (Wt) and talc 4 to 5.5%
% by weight was added and fired at a temperature of 1060° C. to obtain an oxide magnetic material.
【００１７】この場合のタルク及びＰｂＯの添加量と抗
折強度との関係を図１に示す。FIG. 1 shows the relationship between the amounts of talc and PbO added and the bending strength in this case.
【００１８】図１から明らかなように、ＰｂＯが４乃至
４．５重量％で、タルクが５乃至５．５重量％のときの
抗折強度は１６．８乃至１７．８Ｋｇ／ｍｍ２ と非常
に大きくなっている。As is clear from FIG. 1, when PbO is 4 to 4.5% by weight and talc is 5 to 5.5% by weight, the bending strength is extremely high at 16.8 to 17.8 Kg/mm2. It's getting bigger.
【００１９】尚、上述した抗折強度は、酸化物磁性材料
を間隔４０ｍｍで支持した状態でその中間位置に２０ｍ
ｍ／ｍｉｎ の割合で所定の荷重を加えたときの値を示
すものである。Note that the above-mentioned bending strength is determined when the oxide magnetic material is supported at an interval of 40 mm, and when the oxide magnetic material is supported at an interval of 20 m,
It shows the value when a predetermined load is applied at a rate of m/min.
【００２０】例２
Ｆｅ２ Ｏ３ ４７モル％、ＮｉＯ２７モル％、ＣｕＯ
４モル％、ＺｎＯ１７モル％、ＭｎＯ５．０モル％の組
成からなる酸化物磁性原料としてのフェライトに、Ｐｂ
Ｏ０乃至３０重量％、タルク０乃至３０重量％を添加し
、例１と同一の条件で焼成して酸化物磁性材料を得た。Example 2 47 mol% Fe2O3, 27 mol% NiO, CuO
Pb
0 to 30% by weight of O and 0 to 30% by weight of talc were added and fired under the same conditions as in Example 1 to obtain an oxide magnetic material.
【００２１】このときのＪＩＳ法に基く３点曲げ強度の
添加量別の測定結果を図２に示す。FIG. 2 shows the measurement results of three-point bending strength according to the amount of addition based on the JIS method.
【００２２】図２から明らかなように、従来例の添加範
囲に対する３点曲げ強度の最大値１２Ｋｇ／ｍｍ２ に
比べ、ＰｂＯ３．１乃至３０重量％、タルク３．１乃至
３０重量％の範囲で本例の３点曲げ強度は向上し、特に
ＰｂＯ５重量％、タルク７．５重量％のところに１９Ｋ
ｇ／ｍｍ２ を示すピーク値が存在する。As is clear from FIG. 2, compared to the maximum three-point bending strength of 12 kg/mm2 for the addition range of the conventional example, the present invention was found in the range of 3.1 to 30 weight % PbO and 3.1 to 30 weight % talc. The three-point bending strength of the example was improved, especially at 19K at 5% by weight of PbO and 7.5% by weight of talc.
There is a peak value indicating g/mm2.
【００２３】例３
Ｆｅ２ Ｏ３ ４７モル％、ＮｉＯ２７モル％、ＣｕＯ
４モル％、ＺｎＯ１７モル％、ＭｎＯ５．０モル％の組
成からなる酸化物磁性原料としてのフェライトに、Ｐｂ
Ｏ３．１重量％以上、好ましくは４．５重量％程度、タ
ルク３．１重量％以上、好ましくは４重量％程度添加し
、上述した場合と同様な条件で酸化物磁性材料を得た。Example 3 47 mol% Fe2O3, 27 mol% NiO, CuO
Pb
An oxide magnetic material was obtained under the same conditions as described above, adding 3.1% by weight or more of O, preferably about 4.5% by weight, and 3.1% by weight or more of talc, preferably about 4% by weight.
【００２４】この場合のＰｂＯ，タルクの添加量とＪＩ
Ｓ法に基く３点曲げ強度との関係を図３に示す。[0024] In this case, the amount of PbO and talc added and the JI
Figure 3 shows the relationship with the three-point bending strength based on the S method.
【００２５】図３から明らかなように、本例の酸化物磁
性材料は１９Ｋｇ／ｍｍ２ 程度、従来例のＰｂＯ３重
量％、タルク１重量％のものでは１１Ｋｇ／ｍｍ２ 程
度の３点曲げ強度となり、本例では従来例よりも７０％
程度も３点曲げ強度が向上している。As is clear from FIG. 3, the oxide magnetic material of this example has a three-point bending strength of about 19 Kg/mm2, and the conventional example of 3% PbO and 1% talc has a three-point bending strength of about 11Kg/mm2, which is higher than the present invention. In the example, 70% more than the conventional example
The three-point bending strength has also improved.
【００２６】例４
上述した例１の酸化物磁性材料及び従来例の酸化物磁性
材料により各々１０個のドラム型コアを作成し、各々の
芯折れ強度を測定した。その結果を図４に示す。Example 4 Ten drum-shaped cores were prepared using the oxide magnetic material of Example 1 and the conventional oxide magnetic material, and the core breakage strength of each core was measured. The results are shown in FIG.
【００２７】本例では、芯折れ強度の最大が２．４８Ｋ
ｇｆ 、最小が１．６２Ｋｇｆ 、平均で２．０３Ｋｇ
ｆ であったのに対し、従来例では最大で１．５２Ｋｇ
ｆ 、最小で０．８０Ｋｇｆ 、平均で１．２０Ｋｇｆ
であった。この結果から、本例では従来例よりも７０
％程度芯折れ強度が向上していることが判明した。In this example, the maximum core breaking strength is 2.48K.
gf, minimum is 1.62Kgf, average is 2.03Kg
f, whereas in the conventional example the maximum weight was 1.52Kg.
f, minimum 0.80Kgf, average 1.20Kgf
Met. From this result, it can be seen that in this example, 70
It was found that the core breakage strength was improved by about %.
【００２８】以上詳述したように、本実施例の酸化物磁
性材料は、従来例に比べ、抗折強度、３点曲げ強度が大
幅に向上し、また、ドラム型コアとした場合にもその芯
折れ強度が大幅に向上する。As described in detail above, the oxide magnetic material of this example has significantly improved bending strength and three-point bending strength compared to the conventional example, and also has excellent flexural strength and 3-point bending strength when used as a drum-shaped core. Core breakage strength is greatly improved.
【００２９】本発明は、上述した実施例に限定されるも
のではなく、その要旨の範囲内で種々の変形が可能であ
る。The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the invention.
【００３０】例えば、添加物としては上述したＳｉＯ２
、タルクの他、タルクを除くＳｉＯ２ 化合物を用い
ても同様に機械的強度を向上させることができる。For example, as an additive, the above-mentioned SiO2
In addition to talc, the mechanical strength can be similarly improved by using a SiO2 compound other than talc.
【００３１】[0031]
【発明の効果】以上説明した本発明によれば、以下の効
果を奏する。[Effects of the Invention] According to the present invention described above, the following effects are achieved.
【００３２】請求項１記載の発明によれば、酸化物磁性
原料にＰｂＯ、ＳｉＯ２ を既述した範囲となるように
含有する構成で、従来例に比べ機械的強度を大幅に向上
させることが可能な酸化物磁性材料を提供することがで
きる。According to the invention described in claim 1, the mechanical strength can be significantly improved compared to the conventional example by containing PbO and SiO2 in the above-mentioned range in the oxide magnetic raw material. oxide magnetic material can be provided.
【００３３】請求項２記載の発明によればＰｂＯ、タル
クを既述した範囲となるように含有する構成で従来例に
比べ機械的強度を大幅に向上させることが可能な酸化物
磁性材料を提供することができる。According to the second aspect of the invention, there is provided an oxide magnetic material that contains PbO and talc within the above-mentioned ranges and can significantly improve mechanical strength compared to conventional examples. can do.
【００３４】請求項３記載の発明によれば、ＰｂＯ及び
タルク以外のＳｉＯ２ 化合物を既述した範囲となるよ
うに含有する構成で従来例に比べ機械的強度を大幅に向
上させることが可能な酸化物磁性材料を提供することが
できる。According to the invention as claimed in claim 3, the oxidation material contains SiO2 compounds other than PbO and talc within the above-mentioned range, making it possible to significantly improve the mechanical strength compared to the conventional example. A magnetic material can be provided.
【図１】本発明の実施例における例１のＰｂＯ、タルク
含有量と抗折強度との関係を示すグラフFIG. 1 is a graph showing the relationship between PbO and talc content and bending strength in Example 1 in Examples of the present invention.
【図２】本発明
の実施例における例２のＰｂＯ、タルク含有量と３点曲
げ強度との関係を示すグラフFIG. 2 is a graph showing the relationship between the PbO and talc contents and the three-point bending strength of Example 2 in Examples of the present invention.
【図３】本発明の実施例に
おける例３のＰｂＯ、タルク含有量と３点曲げ強度との
関係を示すグラフFIG. 3 is a graph showing the relationship between the PbO and talc contents and the three-point bending strength of Example 3 in Examples of the present invention.
【図４】本発明、従来例の各酸化物磁
性材料によりドラム型コアを作成した場合の各々の芯折
れ強度を示すグラフFIG. 4 is a graph showing the core breakage strength of drum-shaped cores made from the oxide magnetic materials of the present invention and conventional examples.
Claims (3)
３０重量％及びＳｉＯ２ ０．１乃至３０重量％を含有
したことを特徴とする酸化物磁性材料。1. An oxide magnetic material characterized in that an oxide magnetic raw material contains 3.1 to 30% by weight of PbO and 0.1 to 30% by weight of SiO2.
３０重量％及びタルク３．１乃至３０重量％を含有した
ことを特徴とする酸化物磁性材料。2. An oxide magnetic material characterized in that the oxide magnetic raw material contains 3.1 to 30% by weight of PbO and 3.1 to 30% by weight of talc.
０重量％及びタルクを除くＳｉＯ２ 化合物０．１乃至
３０重量％を含有したことを特徴とする酸化物磁性材料
。[Claim 3] PbO3.1 to 3 as the oxide magnetic raw material
An oxide magnetic material characterized in that it contains 0.1 to 30 weight % of an SiO2 compound excluding talc.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3065625A JP2898772B2 (en) | 1991-03-06 | 1991-03-06 | Oxide magnetic material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3065625A JP2898772B2 (en) | 1991-03-06 | 1991-03-06 | Oxide magnetic material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04278502A true JPH04278502A (en) | 1992-10-05 |
| JP2898772B2 JP2898772B2 (en) | 1999-06-02 |
Family
ID=13292391
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3065625A Expired - Lifetime JP2898772B2 (en) | 1991-03-06 | 1991-03-06 | Oxide magnetic material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2898772B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0891955A1 (en) * | 1997-07-16 | 1999-01-20 | TDK Corporation | Ferrite and inductor |
| US6183659B1 (en) * | 1998-10-23 | 2001-02-06 | Tdk Corporation | Ferrite oxide magnetic material |
-
1991
- 1991-03-06 JP JP3065625A patent/JP2898772B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0891955A1 (en) * | 1997-07-16 | 1999-01-20 | TDK Corporation | Ferrite and inductor |
| US6033594A (en) * | 1997-07-16 | 2000-03-07 | Tdk Corporation | Ferrite and inductor |
| US6183659B1 (en) * | 1998-10-23 | 2001-02-06 | Tdk Corporation | Ferrite oxide magnetic material |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2898772B2 (en) | 1999-06-02 |
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