JP2000173812A - Manufacture of anisotropic ferrite magnet - Google Patents
Manufacture of anisotropic ferrite magnetInfo
- Publication number
- JP2000173812A JP2000173812A JP10348794A JP34879498A JP2000173812A JP 2000173812 A JP2000173812 A JP 2000173812A JP 10348794 A JP10348794 A JP 10348794A JP 34879498 A JP34879498 A JP 34879498A JP 2000173812 A JP2000173812 A JP 2000173812A
- Authority
- JP
- Japan
- Prior art keywords
- type hexagonal
- hexagonal ferrite
- powder
- ferrite
- sintered body
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、モーターなどの電
気機器で用いられる異方性フェライト磁石の製造方法に
関するものであり、バリウムフェライト磁石またはスト
ロンチウムフェライト磁石の製造方法に関する。The present invention relates to a method for producing an anisotropic ferrite magnet used in electric equipment such as a motor, and more particularly to a method for producing a barium ferrite magnet or a strontium ferrite magnet.
【０００２】[0002]
【従来の技術】近年、高保持力磁性材料として、フェラ
イト磁石と比べて磁気特性が優れている希土類磁石の利
用比率が高くなっている。その影響もあり、フェライト
磁石には、低価格で高性能なものが要求されている。こ
の要求に答えてフェライト磁石の磁気特性を高めるため
には、単磁区からなるＭ型六方晶フェライト（マグネト
プランバイト）粒子を高配向させて、高密度で焼結させ
ることが重要である。2. Description of the Related Art In recent years, as a high coercive force magnetic material, the use ratio of rare earth magnets having better magnetic properties than ferrite magnets has increased. Due to this effect, low cost and high performance ferrite magnets are required. In order to respond to this requirement and to improve the magnetic properties of the ferrite magnet, it is important that M-type hexagonal ferrite (magnetoplumbite) particles composed of a single magnetic domain be highly oriented and sintered at a high density.
【０００３】そして、通常、このようなフェライト磁石
は、出発原料を仮焼し、粉砕して、単磁区からなるＭ型
六方晶フェライト粒子を得た後、この粒子を磁場中でｃ
軸配向させて成形した後、焼成して得られている。[0003] Usually, such a ferrite magnet is obtained by calcining and pulverizing a starting material to obtain M-type hexagonal ferrite particles composed of a single magnetic domain.
It is obtained by firing after shaping with axial orientation.
【０００４】なお、単磁区のＭ型六方晶フェライト粒子
は、ｃ軸配向させるためには六角板状粒子であることが
望ましいが、ボールミル、アトライター、振動ミルなど
を用いた通常の粉砕では六角板状粒子は得られない。六
角板状粒子を得る方法として、フラックス（Ｋ2ＳＯ4な
どの硫酸塩等）中に板状粒子を析出させる方法や、ガラ
ス（Ｂ2Ｏ3）中に微結晶化させる方法などの種々の方法
が提案されているが（特公昭４２−１９０６４号公報、
特公昭５５−４９０３０号公報、特公昭５７−１２５１
８号公報、特公昭５８−２０８９０号公報、特開昭５９
−１４６９４４号公報、特開昭６０−９０８２９号公
報）、いずれもコストアップとなるため、通常の粉砕に
よるフェライト磁石の製造が最も一般的に行なわれてい
る。The M-type hexagonal ferrite particles having a single magnetic domain are desirably hexagonal plate-shaped particles for c-axis orientation. No plate-like particles are obtained. Various methods for obtaining hexagonal plate-like particles, such as a method of depositing plate-like particles in a flux (sulfate such as K 2 SO 4 ) and a method of micro-crystallizing in glass (B 2 O 3 ), are used. A method has been proposed (Japanese Patent Publication No. 42-19064,
JP-B-55-49030, JP-B-57-1251
8, JP-B-58-20890, JP-A-59-20890
No. 146944, Japanese Patent Application Laid-Open No. Sho 60-90829), the production of ferrite magnets by ordinary pulverization is most commonly performed because of increased cost.
【０００５】[0005]
【発明が解決しようとする課題】従来のＭ型六方晶フェ
ライト粒子の粉砕は、高密度の焼結体を得ることを目的
とするものであが、このＭ型六方晶フェライト粒子は硬
くて摩砕粉砕がおこるため、サブミクロン粒子が多数発
生し、粒度分布が大きくなるという問題点を有してい
た。また、その粉砕に要する費用を無視できず、低コス
ト化の妨げとなっていた。The conventional pulverization of M-type hexagonal ferrite particles is intended to obtain a high-density sintered body. Since crushing and pulverization occur, there is a problem that a large number of submicron particles are generated and the particle size distribution is increased. Further, the cost required for the pulverization cannot be neglected, which hinders cost reduction.
【０００６】また、通常、Ｍ型六方晶フェライト粒子を
高配向させるには磁場中プレスでｃ軸配向させるのが一
般的であるが、これらの粉砕粒子では配向度に限界があ
る上に、粉砕条件により配向性が変化するという問題点
を有していた。さらに、大型成形体を作製するために
は、大電流または高巻線数の磁場発生コイルを装備した
成形機とその金型が必要であり、コストアップの要因と
なっていた。Usually, in order to highly orient M-type hexagonal ferrite particles, c-axis orientation is carried out by a press in a magnetic field. There was a problem that the orientation changed depending on the conditions. Further, in order to produce a large-sized molded body, a molding machine equipped with a magnetic field generating coil having a large current or a high number of windings and a mold for the molding machine are required, which has caused a cost increase.
【０００７】そこで、本発明の目的は、高密度、高配向
でありながら、磁場中プレスによる配向を不要とするこ
とでコストを低減した、異方性フェライト磁石の製造方
法を提供することにある。It is an object of the present invention to provide a method for producing an anisotropic ferrite magnet, which has a high density and a high orientation, and reduces the cost by eliminating the need for orientation by pressing in a magnetic field. .
【０００８】[0008]
【課題を解決するための手段】上記目的を達成するた
め、本発明の異方性フェライト磁石の製造方法は、一般
式Ｍ2Ｆｅ2Ｆｅ12Ｏ22（ただし、ＭはＢａおよびＳｒの
うちの少なくとも１種）で表わされるＹ型六方晶フェラ
イトの粉体を一軸加圧成形し、その後焼成して、一般式
ＭＦｅ12Ｏ19（ただし、ＭはＢａおよびＳｒのうちの少
なくとも１種）で表わされるＭ型六方晶フェライトを主
成分とする焼結体を得ることを特徴とする。Means for Solving the Problems In order to achieve the above object, a method for producing an anisotropic ferrite magnet of the present invention uses a general formula M 2 Fe 2 Fe 12 O 22 (where M is one of Ba and Sr). Y-type hexagonal ferrite powder represented by at least one kind) is uniaxially pressed and then fired, and is represented by a general formula MFe 12 O 19 (where M is at least one kind of Ba and Sr). A sintered body containing M-type hexagonal ferrite as a main component.
【０００９】そして、前記一軸加圧成形する前のＹ型六
方晶フェライトの粉体に、Ｆｅ化合物、またはＦｅ化合
物とＭ化合物（ただし、ＭはＢａおよびＳｒのうちの少
なくとも１種）を添加し、ＭＦｅ12Ｏ19組成に調合する
ことを特徴とする。Then, an Fe compound or an Fe compound and an M compound (where M is at least one of Ba and Sr) is added to the Y-type hexagonal ferrite powder before the uniaxial pressing. , MFe 12 O 19 composition.
【００１０】また、前記Ｙ型六方晶フェライトの粉体の
量は５０ｗｔ％以上であることを特徴とする。The amount of the Y-type hexagonal ferrite powder is at least 50 wt%.
【００１１】さらに、前記一軸加圧成形する前の粉体
に、ＳｉＯ2を１．０ｗｔ％以下、かつＣａＯを１．０
ｗｔ％以下添加することを特徴とする。Further, the powder before the uniaxial pressing is made to contain 1.0% by weight or less of SiO 2 and 1.0% by weight of CaO.
It is characterized in that it is added in an amount of not more than wt%.
【００１２】なお、焼成雰囲気については、Ｆｅ2+をＦ
ｅ3+に変化させるために、空気中または、酸素雰囲気中
での焼成が必要である。また、焼成温度は、１１００〜
１３００℃の範囲が好ましい。これは、１１００℃未満
では、ＭＦｅ12Ｏ19（ただし、ＭはＢａおよびＳｒのう
ちの少なくとも１種）への反応が十分に起こらず、一
方、１３００℃を超えると、結晶粒子が異常に成長して
保持力ｂＨｃ特性が低下するためである。そして、焼成
時間は、焼成温度と関係するが、ＭＦｅ12Ｏ１９への反
応を完結させるためには、通常６時間程度が好ましい。As for the firing atmosphere, Fe 2+ is converted to F
In order to change to e 3+ , firing in air or an oxygen atmosphere is required. The firing temperature is 1100
A range of 1300 ° C. is preferred. This is because below 1100 ° C., the reaction to MFe 12 O 19 (where M is at least one of Ba and Sr) does not sufficiently occur, while above 1300 ° C., the crystal grains grow abnormally. This is because the holding force bHc characteristic is reduced. The firing time is related to the firing temperature, but is preferably about 6 hours in order to complete the reaction to MFe 12 O 19 .
【００１３】[0013]
【発明の実施の形態】以下、本発明の実施の形態を実施
例に基づき説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples.
【００１４】（実施例１）まず、出発原料としてＦｅ2
Ｏ3およびＢａＣＯ3の粉体を用意した。その後、Ｆｅ2
Ｏ3およびＢａＣＯ3をＢａ2Ｆｅ2Ｆｅ12Ｏ22組成になる
ように調合し、調合原料に対して２倍重量の純水を加え
た後、ボールミルで２４時間混合・粉砕し、濾過脱水し
た。ふるいに通した後、酸素分圧１×１０-4ＭＰａの雰
囲気中、１１００℃で仮焼してＹ型六方晶フェライトで
あるＢａ2Ｆｅ2Ｆｅ12Ｏ22の六角板状粒子を得た。(Example 1) First, Fe 2 was used as a starting material.
Powders of O 3 and BaCO 3 were prepared. Then, Fe 2
The O 3 and BaCO 3 were blended so as to Ba 2 Fe 2 Fe 12 O 22 composition, after addition of pure water 2 times by weight relative to the formulation material, 24 hours were mixed and pulverized in a ball mill, and filtering and dewatering . After passing through a sieve, it was calcined at 1100 ° C. in an atmosphere having an oxygen partial pressure of 1 × 10 −4 MPa to obtain hexagonal plate-like particles of Y 2 type hexagonal ferrite Ba 2 Fe 2 Fe 12 O 22 .
【００１５】次に、このＢａ2Ｆｅ2Ｆｅ12Ｏ22に酢酸ビ
ニル系バインダと純水を添加した後、ボールミルで６時
間混合し、スプレードライヤーで造粒した。なお、この
ボールミル混合を長時間行なうと、六角板状の粒子が崩
れて焼結体の配向性が崩れるため好ましくない。次に、
得られた造粒粉を一軸加圧成形機で成形し、１２００℃
で焼成してＢａＦｅ12Ｏ19で表わされるＭ型六方晶フェ
ライトを主成分とする焼結体を得た。Next, after adding a vinyl acetate-based binder and pure water to the Ba 2 Fe 2 Fe 12 O 22 , the mixture was mixed for 6 hours by a ball mill and granulated by a spray drier. If the ball mill mixing is performed for a long period of time, hexagonal plate-like particles are broken and the orientation of the sintered body is broken, which is not preferable. next,
The obtained granulated powder is molded by a uniaxial pressing machine,
To obtain a sintered body mainly composed of M-type hexagonal ferrite represented by BaFe 12 O 19 .
【００１６】得られた焼結体の密度は５．２ｇ／ｃｍ3
（Ｘ線理論密度比９８％）であり、高密度な焼結体が得
られた。また、配向度は８５％であり、高配向な焼結体
が得られた。さらに、焼結体の磁気特性は、残留磁束密
度Ｂｒが２．６ｋＧ、保持力ｂＨｃが２．０ｋＯｅ、最
大エネルギー積（ＢＨ）ｍａｘが１．８ＧＯｅと良好で
あった。The density of the obtained sintered body is 5.2 g / cm 3
(X-ray theoretical density ratio: 98%), and a high-density sintered body was obtained. The degree of orientation was 85%, and a highly oriented sintered body was obtained. Further, the magnetic properties of the sintered body were as good as residual magnetic flux density Br of 2.6 kG, coercive force bHc of 2.0 kOe, and maximum energy product (BH) max of 1.8 GOe.
【００１７】なお、配向度は、焼結体のＸ線回折分析に
より、次式で求めた。配向度（％）＝［ΣＩ（００ｌ）
／ΣＩ（ｈｋｌ）］×１００ただし、Ｉ（００ｌ）は、
Ｘ線回折測定範囲１５〜６０°間の（００ｌ）面のＸ線
回折強度であり、Ｉ（ｈｋｌ）は、Ｘ線回折測定範囲１
５〜６０°間の（ｈｋｌ）面のＸ線回折強度である。The degree of orientation was determined by the following equation by X-ray diffraction analysis of the sintered body. Degree of orientation (%) = [ΣI (00l)
/ ΣI (hkl)] × 100 where I (001) is
The X-ray diffraction intensity of the (00l) plane between 15 and 60 ° in the X-ray diffraction measurement range, and I (hkl) is the X-ray diffraction measurement range 1
It is the X-ray diffraction intensity of the (hkl) plane between 5 and 60 °.
【００１８】（実施例２）まず、出発原料としてＦｅ2
Ｏ3、ＢａＣＯ3、ＣａＣＯ3およびＳｉＯ2の粉体を用意
した。その後、Ｆｅ2Ｏ3およびＢａＣＯ3をＢａ2Ｆｅ2
Ｆｅ12Ｏ22組成になるように調合し、調合原料に対して
２倍重量の純水を加えた後、ボールミルで２４時間混合
・粉砕し、濾過脱水した。ふるいに通した後、酸素分圧
１×１０-4ＭＰａの雰囲気中、１１００℃で仮焼してＹ
型六方晶フェライトであるＢａ2Ｆｅ2Ｆｅ12Ｏ22の六角
板状粒子を得た。Example 2 First, Fe 2 was used as a starting material.
Powders of O 3 , BaCO 3 , CaCO 3 and SiO 2 were prepared. Then, Fe 2 O 3 and BaCO 3 were converted to Ba 2 Fe 2
The mixture was prepared so as to have a composition of Fe 12 O 22 , and after adding twice the weight of pure water to the prepared raw materials, the mixture was mixed and pulverized with a ball mill for 24 hours, and filtered and dewatered. After passing through a sieve, it is calcined at 1100 ° C. in an atmosphere of an oxygen partial pressure of 1 × 10 −4 MPa to obtain Y.
Hexagonal plate-like particles of Ba 2 Fe 2 Fe 12 O 22 , which is a type hexagonal ferrite, were obtained.
【００１９】次に、このＢａ2Ｆｅ2Ｆｅ12Ｏ22に対し
て、ＣａＯ換算で０．２ｗｔ％のＣａＣＯ3と０．２ｗ
ｔ％のＳｉＯ2を加え、酢酸ビニル系バインダと純水を
添加した後、ボールミルで６時間混合し、スプレードラ
イヤーで造粒した。次に、得られた造粒粉を一軸加圧成
形機で成形し、１２００℃で焼成してＢａＦｅ12Ｏ19で
表わされるＭ型六方晶フェライトを主成分とする焼結体
を得た。Next, with respect to the Ba 2 Fe 2 Fe 12 O 22 , 0.2 wt% of CaCO 3 and 0.2 w
After adding t% of SiO 2 , adding a vinyl acetate-based binder and pure water, the mixture was mixed by a ball mill for 6 hours, and granulated by a spray drier. Next, the obtained granulated powder was molded by a uniaxial pressing machine and fired at 1200 ° C. to obtain a sintered body mainly composed of M-type hexagonal ferrite represented by BaFe 12 O 19 .
【００２０】得られた焼結体の密度は５．２ｇ／ｃｍ3
（Ｘ線理論密度比９８％）であり、高密度な焼結体が得
られた。また、配向度は８６％であり、高配向な焼結体
が得られた。また、仮焼粉体にＣａＣＯ3およびＳｉＯ2
を添加したことにより、粒径１〜３μｍの焼結体が得ら
れた。さらに、焼結体の磁気特性は、Ｂｒが２．８ｋ
Ｇ、ｂＨｃが３．０ｋＯｅ、（ＢＨ）ｍａｘが２．５Ｇ
Ｏｅと良好であった。The density of the obtained sintered body is 5.2 g / cm 3
(X-ray theoretical density ratio: 98%), and a high-density sintered body was obtained. The degree of orientation was 86%, and a highly oriented sintered body was obtained. CaCO 3 and SiO 2 were added to the calcined powder.
, A sintered body having a particle size of 1 to 3 μm was obtained. Further, the magnetic characteristics of the sintered body are as follows: Br is 2.8 k
G, bHc is 3.0 kOe, (BH) max is 2.5 G
Oe was good.
【００２１】（実施例３）まず、出発原料としてＦｅ2
Ｏ3、ＢａＣＯ3、ＣａＣＯ3およびＳｉＯ2の粉体を用意
した。その後、Ｆｅ2Ｏ3およびＢａＣＯ3をＢａ2Ｆｅ2
Ｆｅ12Ｏ22組成になるように調合し、調合原料に対して
２倍重量の純水を加えた後、ボールミルで２４時間混合
・粉砕し、濾過脱水した。ふるいに通した後、酸素分圧
１×１０-4ＭＰａの雰囲気中、１１００℃で仮焼してＹ
型六方晶フェライトであるＢａ2Ｆｅ2Ｆｅ12Ｏ22の六角
板状粒子を得た。Example 3 First, Fe 2 was used as a starting material.
Powders of O 3 , BaCO 3 , CaCO 3 and SiO 2 were prepared. Then, Fe 2 O 3 and BaCO 3 were converted to Ba 2 Fe 2
The mixture was prepared so as to have a composition of Fe 12 O 22 , and after adding twice the weight of pure water to the prepared raw materials, the mixture was mixed and pulverized with a ball mill for 24 hours, and filtered and dewatered. After passing through a sieve, it is calcined at 1100 ° C. in an atmosphere of an oxygen partial pressure of 1 × 10 −4 MPa to obtain Y.
Hexagonal plate-like particles of Ba 2 Fe 2 Fe 12 O 22 , which is a type hexagonal ferrite, were obtained.
【００２２】次に、このＢａ2Ｆｅ2Ｆｅ12Ｏ22（Ｙ型
相）に対して、表１に示す量のＦｅ化合物としてのＦｅ
2Ｏ3、Ｂａ化合物としてのＢａＣＯ3をＢａＦｅ12Ｏ19
組成になるように加え、さらに、Ｂａ2Ｆｅ2Ｆｅ12Ｏ22
に対して、ＣａＯ換算で０．２ｗｔ％のＣａＣＯ3と
０．２ｗｔ％のＳｉＯ2を加え、酢酸ビニル系バインダ
と純水を添加した後、ボールミルで６時間混合し、スプ
レードライヤーで造粒した。次に、得られた造粒粉を一
軸加圧成形機で成形し、１２００℃で焼成してＢａＦｅ
12Ｏ19で表わされるＭ型フェライトの焼結体を得た。Next, with respect to the Ba 2 Fe 2 Fe 12 O 22 (Y type phase), the amount of Fe
2 O 3 , BaCO 3 as a Ba compound is converted to BaFe 12 O 19
In addition to the composition, Ba 2 Fe 2 Fe 12 O 22
Then, 0.2 wt% of CaCO 3 and 0.2 wt% of SiO 2 in terms of CaO were added, a vinyl acetate-based binder and pure water were added, followed by mixing for 6 hours by a ball mill and granulation by a spray drier. . Next, the obtained granulated powder is molded by a uniaxial press molding machine, fired at 1200 ° C., and
A sintered body of M-type ferrite represented by 12 O 19 was obtained.
【００２３】得られた焼結体の密度、配向度、磁気特性
（Ｂｒ、ｂＨｃ、（ＢＨ）ｍａｘ）を、表１に示す。Table 1 shows the density, degree of orientation, and magnetic properties (Br, bHc, (BH) max) of the obtained sintered body.
【００２４】[0024]
【表１】 [Table 1]
【００２５】表１から明らかなとおり、一軸加圧成形す
る前のＹ型六方晶フェライトの粉体に、Ｆｅ化合物、ま
たはＦｅ化合物とＢａ化合物を添加し、ＢａＦｅ12Ｏ19
組成に調合することにより、焼成密度が高く、配向度お
よび磁気特性（Ｂｒ、ｂＨｃ、（ＢＨ）ｍａｘ）に優れ
た、異方性フェライト磁石を得ることができる。As is clear from Table 1, an Fe compound or an Fe compound and a Ba compound were added to the powder of the Y-type hexagonal ferrite before the uniaxial pressing, and BaFe 12 O 19
By adjusting the composition, it is possible to obtain an anisotropic ferrite magnet having a high firing density, an excellent degree of orientation and excellent magnetic properties (Br, bHc, (BH) max).
【００２６】なお、表１の試料番号１〜３に示すよう
に、Ｙ型六方晶フェライトの粉体に添加するＦｅ化合物
とＢａ化合物の量は５０ｗｔ％未満、すなわちＹ型六方
晶フェライトの粉体の量が５０ｗｔ％以上の場合が、特
に配向度、磁気特性の面から好ましい。As shown in Sample Nos. 1 to 3 in Table 1, the amounts of the Fe compound and the Ba compound added to the powder of the Y-type hexagonal ferrite are less than 50 wt%, that is, the powder of the Y-type hexagonal ferrite. Is preferably 50 wt% or more, particularly in view of the degree of orientation and magnetic properties.
【００２７】（実施例４）まず、出発原料としてＦｅ2
Ｏ3、ＳｒＣＯ3、ＣａＣＯ3およびＳｉＯ2の粉体を用意
した。その後、Ｆｅ2Ｏ3およびＳｒＣＯ3をＳｒ2Ｆｅ2
Ｆｅ12Ｏ22組成になるように調合し、調合原料に対して
２倍重量の純水を加えた後、ボールミルで２４時間混合
・粉砕し、濾過脱水した。ふるいに通した後、酸素分圧
１×１０-4ＭＰａの雰囲気中、１１００℃で仮焼してＹ
型六方晶フェライトであるＳｒ2Ｆｅ2Ｆｅ12Ｏ22の六角
板状粒子を得た。Example 4 First, Fe 2 was used as a starting material.
Powders of O 3 , SrCO 3 , CaCO 3 and SiO 2 were prepared. Thereafter, Fe 2 O 3 and SrCO 3 were converted to Sr 2 Fe 2
The mixture was prepared so as to have a composition of Fe 12 O 22 , and after adding twice the weight of pure water to the prepared raw materials, the mixture was mixed and pulverized with a ball mill for 24 hours, and filtered and dewatered. After passing through a sieve, it is calcined at 1100 ° C. in an atmosphere of an oxygen partial pressure of 1 × 10 −4 MPa to obtain Y.
Hexagonal plate-like particles of Sr 2 Fe 2 Fe 12 O 22 , which is a type hexagonal ferrite, were obtained.
【００２８】次に、このＳｒ2Ｆｅ2Ｆｅ12Ｏ22に対し
て、Ｆｅ2Ｏ3をＳｒＦｅ12Ｏ19組成になるように加え、
さらに、Ｓｒ2Ｆｅ2Ｆｅ12Ｏ22に対して、ＣａＯ換算で
０．２ｗｔ％のＣａＣＯ3と０．２ｗｔ％のＳｉＯ2を加
え、酢酸ビニル系バインダと純水を添加した後、ボール
ミルで６時間混合し、スプレードライヤーで造粒した。
次に、得られた造粒粉を一軸加圧成形機で成形し、１２
００℃で焼成してＳｒＦｅ12Ｏ19で表わされるＭ型フェ
ライトの焼結体を得た。Next, Fe 2 O 3 was added to the Sr 2 Fe 2 Fe 12 O 22 so as to have a SrFe 12 O 19 composition.
Further, 0.2 wt% of CaCO 3 and 0.2 wt% of SiO 2 in terms of CaO were added to Sr 2 Fe 2 Fe 12 O 22 , and a vinyl acetate binder and pure water were added. Mix for hours and granulate with a spray drier.
Next, the obtained granulated powder was molded by a uniaxial pressing machine,
By firing at 00 ° C., a sintered body of M-type ferrite represented by SrFe 12 O 19 was obtained.
【００２９】得られた焼結体の配向度は９０％であり、
高配向な焼結体が得られた。また、その磁気特性は、Ｂ
ｒが４．０ｋＧ、ｂＨｃが３．５ｋＯｅ、（ＢＨ）ｍａ
ｘが３．８ＧＯｅであり、実施例１、２のＢａＦｅ12Ｏ
19焼結体より優れた磁気特性が得られた。The degree of orientation of the obtained sintered body is 90%,
A highly oriented sintered body was obtained. In addition, the magnetic characteristics are B
r is 4.0 kG, bHc is 3.5 kOe, (BH) ma
x is 3.8 GOe, and the BaFe 12 O of Examples 1 and 2
Magnetic properties superior to those of the 19 sintered bodies were obtained.
【００３０】（実施例５）まず、出発原料としてＦｅ2
Ｏ3、ＢａＣＯ3、ＣａＣＯ3およびＳｉＯ2の粉体を用意
した。その後、Ｆｅ2Ｏ3およびＢａＣＯ3をＢａ2Ｆｅ2
Ｆｅ12Ｏ22組成になるように調合し、調合原料に対して
２倍重量の純水を加えた後、ボールミルで２４時間混合
・粉砕し、濾過脱水した。その後、ふるいに通して、酸
素分圧１×１０-4ＭＰａの雰囲気中、１１００℃で仮焼
してＹ型六方晶フェライトであるＢａ2Ｆｅ2Ｆｅ12Ｏ22
の六角板状粒子を得た。Example 5 First, Fe 2 was used as a starting material.
Powders of O 3 , BaCO 3 , CaCO 3 and SiO 2 were prepared. Then, Fe 2 O 3 and BaCO 3 were converted to Ba 2 Fe 2
The mixture was prepared so as to have a composition of Fe 12 O 22 , and after adding twice the weight of pure water to the prepared raw materials, the mixture was mixed and pulverized with a ball mill for 24 hours, and filtered and dewatered. Thereafter, the mixture is passed through a sieve, and calcined at 1100 ° C. in an atmosphere having an oxygen partial pressure of 1 × 10 −4 MPa to obtain Ba 2 Fe 2 Fe 12 O 22 which is a Y-type hexagonal ferrite.
To obtain hexagonal plate-like particles.
【００３１】次に、このＢａ2Ｆｅ2Ｆｅ12Ｏ22に対し
て、Ｆｅ2Ｏ3をＢａＦｅ12Ｏ19組成になるように加え、
さらに、Ｂａ2Ｆｅ2Ｆｅ12Ｏ22に対して、表２に示す量
のＣａＯに換算したＣａＣＯ3とＳｉＯ2を加え、酢酸ビ
ニル系バインダと純水を添加した後、ボールミルで６時
間混合し、スプレードライヤーで造粒した。次に、得ら
れた造粒粉を一軸加圧成形機で成形し、１２００℃で焼
成してＢａＦｅ12Ｏ19で表わされるＭ型フェライトの焼
結体を得た。Next, Fe 2 O 3 was added to the Ba 2 Fe 2 Fe 12 O 22 so as to have a BaFe 12 O 19 composition.
Further, CaCO 3 and SiO 2 converted into CaO in the amounts shown in Table 2 were added to Ba 2 Fe 2 Fe 12 O 22 , a vinyl acetate-based binder and pure water were added, and the mixture was mixed by a ball mill for 6 hours. And granulated with a spray dryer. Next, the obtained granulated powder was molded by a uniaxial pressing machine and fired at 1200 ° C. to obtain a sintered body of M-type ferrite represented by BaFe 12 O 19 .
【００３２】得られた焼結体の密度、配向度、磁気特性
（Ｂｒ、ｂＨｃ、（ＢＨ）ｍａｘ）を、表２に示す。Table 2 shows the density, orientation degree, and magnetic properties (Br, bHc, (BH) max) of the obtained sintered body.
【００３３】[0033]
【表２】 [Table 2]
【００３４】表２から明らかなとおり、ＳｉＯ2および
ＣａＯの添加量は、それぞれ１．０ｗｔ％以下が好まし
い。表２の試料番号８、９に示すように、添加量がこの
値を超えると、マグネトプランバイト粒子の構成比率が
減少するため、磁気特性（Ｂｒ、ｂＨｃ、（ＢＨ）ｍａ
ｘ）が低下する。As is evident from Table 2, the addition amounts of SiO 2 and CaO are each preferably 1.0% by weight or less. As shown in Sample Nos. 8 and 9 in Table 2, when the addition amount exceeds this value, the composition ratio of the magnetoplumbite particles decreases, so that the magnetic properties (Br, bHc, (BH) ma
x) decreases.
【００３５】（比較例）まず、出発原料としてＦｅ2Ｏ3
およびＢａＣＯ3の粉体を用意した。その後、Ｆｅ2Ｏ3
およびＢａＣＯ3をＢａＦｅ12Ｏ19組成になるように調
合し、調合原料に対して２倍重量の純水を加えた後、ボ
ールミルで２４時間混合・粉砕し、濾過脱水した。その
後、ふるいに通して、１１００℃で仮焼した。Comparative Example First, Fe 2 O 3 was used as a starting material.
And BaCO 3 powder were prepared. Then, Fe 2 O 3
And BaCO 3 were prepared to have a BaFe 12 O 19 composition, and after adding twice the weight of pure water to the prepared raw materials, the mixture was mixed and pulverized for 24 hours in a ball mill, and filtered and dewatered. Then, it was calcined at 1100 ° C. through a sieve.
【００３６】次に、この仮焼粉体に酢酸ビニル系バイン
ダと純水を添加した後、ボールミルで６時間混合し、ス
プレードライヤーで造粒した。次に、得られた造粒粉を
一軸加圧成形機で成形し、１２００℃で焼成した。Next, a vinyl acetate-based binder and pure water were added to the calcined powder, mixed for 6 hours with a ball mill, and granulated with a spray drier. Next, the obtained granulated powder was molded with a uniaxial pressing machine and fired at 1200 ° C.
【００３７】得られた焼結体の密度は５．０ｇ／ｃｍ3
（Ｘ線理論密度比、９４％）であり、高密度な焼結体が
得られた。しかしながら、X線回折分析による配向度は
５５％であり、磁場配向工程なしで高配向した焼結体は
得られなかった。また、得られた磁気特性は、Ｂｒが
２．０ｋＧ、ｂＨｃが２．０ｋＯｅ、（ＢＨ）ｍａｘが
１．２ＧＯｅであった。The density of the obtained sintered body is 5.0 g / cm 3
(X-ray theoretical density ratio, 94%), and a high-density sintered body was obtained. However, the degree of orientation by X-ray diffraction analysis was 55%, and a highly oriented sintered body could not be obtained without a magnetic field orientation step. The obtained magnetic characteristics were Br of 2.0 kG, bHc of 2.0 kOe, and (BH) max of 1.2 GOe.
【００３８】[0038]
【発明の効果】以上の説明で明らかなように、本発明の
異方性フェライト磁石の製造方法は、六角板状粒子を得
やすい、一般式Ｍ2Ｆｅ2Ｆｅ12Ｏ22（ただし、ＭはＢａ
およびＳｒのうちの少なくとも１種）で表わされるＹ型
六方晶フェライトの粉体を一軸加圧成形し、その後焼成
して、一般式ＭＦｅ12Ｏ19（ただし、ＭはＢａおよびＳ
ｒのうちの少なくとも１種）で表わされるＭ型六方晶フ
ェライトを主成分とする焼結体を得る方法である。As is apparent from the above description, the method for producing an anisotropic ferrite magnet of the present invention provides a general formula M 2 Fe 2 Fe 12 O 22 (where M is Ba
Y-type hexagonal ferrite powder represented by at least one of Sr and Sr is uniaxially pressed and then fired to obtain a general formula MFe 12 O 19 (where M is Ba and Sr).
This is a method of obtaining a sintered body mainly composed of M-type hexagonal ferrite represented by at least one of r.
【００３９】上記一般式Ｍ2Ｆｅ2Ｆｅ12Ｏ22で表わされ
るＹ型六方晶フェライトは、原料（Ｆｅ2Ｏ3、ＢａＣＯ
3など）を熱処理することで容易に単磁区となる臨界粒
径に近い六角板状粒子として得ることができ、過度な粉
砕工程は不要である。また、Ｙ型六方晶フェライトは板
状粒子であるため、一軸加圧成形して焼成することで、
高いｃ軸配向の焼結体が得られる。The Y-type hexagonal ferrite represented by the general formula M 2 Fe 2 Fe 12 O 22 is a raw material (Fe 2 O 3 , BaCO 3)
3 ) can be easily obtained as hexagonal plate-like particles having a critical particle size close to the critical particle size to be a single magnetic domain, and an excessive pulverization step is unnecessary. In addition, since the Y-type hexagonal ferrite is a plate-like particle, it is formed by uniaxial pressing and firing.
A sintered body with a high c-axis orientation is obtained.
【００４０】したがって、本製造方法によれば、磁場中
成形による磁場配向工程を経ずに、また、フラックス法
やガラス化法などの特別な手法を使わずに、安価に、高
密度・高配向の異方性フェライト磁石を得ることができ
る。また、成形、焼成前にＳｉＯ2、ＣａＯを添加する
ことで、焼成時の粒成長を抑制して、さらに優れた磁気
特性の異方性フェライト磁石を得ることができる。Therefore, according to the present manufacturing method, high-density and high-orientation can be performed at low cost without using a magnetic field orientation step by molding in a magnetic field and without using a special method such as a flux method or a vitrification method. Can be obtained. By adding SiO 2 and CaO before molding and firing, grain growth during firing can be suppressed, and an anisotropic ferrite magnet with even better magnetic properties can be obtained.
【００４１】[0041]
Claims (4)
はＢａおよびＳｒのうちの少なくとも１種）で表わされ
るＹ型六方晶フェライトの粉体を一軸加圧成形し、その
後焼成して、一般式ＭＦｅ12Ｏ19（ただし、ＭはＢａお
よびＳｒのうちの少なくとも１種）で表わされるＭ型六
方晶フェライトを主成分とする焼結体を得ることを特徴
とする、異方性フェライト磁石の製造方法。(1) A general formula M 2 Fe 2 Fe 12 O 22 (where M
Is a uniaxially press-formed powder of a Y-type hexagonal ferrite represented by at least one of Ba and Sr, and then fired to obtain a general formula MFe 12 O 19 (where M is Ba and Sr). A method for producing an anisotropic ferrite magnet, characterized by obtaining a sintered body mainly containing M-type hexagonal ferrite represented by at least one of the following:
ェライトの粉体に、Ｆｅ化合物、またはＦｅ化合物とＭ
化合物（ただし、ＭはＢａおよびＳｒのうちの少なくと
も１種）を添加し、ＭＦｅ12Ｏ19組成に調合することを
特徴とする、請求項１に記載の異方性フェライト磁石の
製造方法。2. The method according to claim 1, wherein the powder of the Y-type hexagonal ferrite before the uniaxial pressing is mixed with an Fe compound or an Fe compound and M
The method for producing an anisotropic ferrite magnet according to claim 1, wherein a compound (where M is at least one of Ba and Sr) is added and the composition is adjusted to an MFe 12 O 19 composition.
５０ｗｔ％以上であることを特徴とする、請求項２に記
載の異方性フェライト磁石の製造方法。3. The method for producing an anisotropic ferrite magnet according to claim 2, wherein the amount of the Y-type hexagonal ferrite powder is 50 wt% or more.
Ｏ2を１．０ｗｔ％以下、かつＣａＯを１．０ｗｔ％以
下添加することを特徴とする、請求項１から３のいずれ
かに記載の異方性フェライト磁石の製造方法。4. The method according to claim 1, wherein the powder before the uniaxial pressure molding is made of Si powder.
The O 2 or less 1.0 wt%, and is characterized by adding the following 1.0 wt% of CaO, method for producing anisotropic ferrite magnet as claimed in any one of claims 1 to 3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10348794A JP2000173812A (en) | 1998-12-08 | 1998-12-08 | Manufacture of anisotropic ferrite magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10348794A JP2000173812A (en) | 1998-12-08 | 1998-12-08 | Manufacture of anisotropic ferrite magnet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000173812A true JP2000173812A (en) | 2000-06-23 |
Family
ID=18399413
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10348794A Pending JP2000173812A (en) | 1998-12-08 | 1998-12-08 | Manufacture of anisotropic ferrite magnet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000173812A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7141311B2 (en) * | 2000-11-21 | 2006-11-28 | Japan Science And Technology Agency | Ferrite thin film for high frequency and method for preparation thereof |
| US10971288B2 (en) | 2014-10-24 | 2021-04-06 | Skyworks Solutions, Inc. | Incorporation of oxides into ferrite material for improved radio radiofrequency properties |
| US11069983B2 (en) | 2014-09-30 | 2021-07-20 | Skyworks Solutions, Inc. | Modified Z-type hexagonal ferrite materials with enhanced resonant frequency |
-
1998
- 1998-12-08 JP JP10348794A patent/JP2000173812A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7141311B2 (en) * | 2000-11-21 | 2006-11-28 | Japan Science And Technology Agency | Ferrite thin film for high frequency and method for preparation thereof |
| US11069983B2 (en) | 2014-09-30 | 2021-07-20 | Skyworks Solutions, Inc. | Modified Z-type hexagonal ferrite materials with enhanced resonant frequency |
| US10971288B2 (en) | 2014-10-24 | 2021-04-06 | Skyworks Solutions, Inc. | Incorporation of oxides into ferrite material for improved radio radiofrequency properties |
| US10984928B2 (en) | 2014-10-24 | 2021-04-20 | Skyworks Solutions, Inc. | Magnetodielectric y-phase strontium hexagonal ferrite materials formed by sodium substitution |
| US11004581B2 (en) | 2014-10-24 | 2021-05-11 | Skyworks Solutions, Inc. | Increased resonant frequency alkali-doped Y-phase hexagonal ferrites |
| US11164689B2 (en) | 2014-10-24 | 2021-11-02 | Skyworks Solutions, Inc. | Increased resonant frequency potassium-doped hexagonal ferrite |
| US11551837B2 (en) | 2014-10-24 | 2023-01-10 | Skyworks Solutions, Inc. | Magnetodielectric Y-phase strontium hexagonal ferrite materials formed by sodium substitution |
| US11742118B2 (en) | 2014-10-24 | 2023-08-29 | Skyworks Solutions, Inc. | Increased resonant frequency alkali-doped Y-phase hexagonal ferrites |
| US11776718B2 (en) | 2014-10-24 | 2023-10-03 | Skyworks Solutions, Inc. | Increased resonant frequency potassium-doped hexagonal ferrite |
| US11869689B2 (en) | 2014-10-24 | 2024-01-09 | Skyworks Solutions, Inc. | Incorporation of oxides into ferrite material for improved radio radiofrequency properties |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI434302B (en) | Oxide magnetic material and preparation method thereof, and ferrite iron sintered magnet and preparation method thereof | |
| JP4367649B2 (en) | Ferrite sintered magnet | |
| EP3364426B1 (en) | Ferrite magnetic material and ferrite sintered magnet | |
| EP3473606B1 (en) | Ferrite sintered magnet | |
| JP2922864B2 (en) | Ferrite magnet and manufacturing method thereof | |
| WO1999034376A1 (en) | Ferrite magnet and process for producing the same | |
| US5958284A (en) | Ferrite magnet and method for producing same | |
| JP2005259751A (en) | Ferrite magnet and its manufacturing method | |
| JP2001135512A (en) | Ferrite magnet powder, magnet using the magnet powder and method of manufacturing both | |
| JP2021052097A (en) | Ferrite sintered magnet | |
| JP2001052912A (en) | Ferrite magnet material, sintered magnet and bonded magnet | |
| JP3506174B2 (en) | Method for producing ferrite magnet and powder thereof | |
| JP2000173812A (en) | Manufacture of anisotropic ferrite magnet | |
| JP2004532524A (en) | Manufacturing method of ferrite type magnet | |
| JP2002141212A (en) | Rotating machine | |
| JPH11307331A (en) | Ferrite magnet | |
| JP2002343616A (en) | Method for manufacturing oxide containing rare earth element | |
| KR102610891B1 (en) | Method for preparing ferrite sintered magnet | |
| JPH0878220A (en) | Manufacture of hexagonal crystal system ferrite | |
| JP2001006912A (en) | Hard ferrite magnet and its manufacture | |
| JP2001274010A (en) | Polar anisotropic cylindrical ferrite magnet and magnetic field granular material | |
| JP3257536B2 (en) | Composite ferrite magnet material | |
| CN113470913A (en) | Ferrite sintered magnet and rotating electrical machine | |
| CN113470912A (en) | Ferrite sintered magnet and rotating electrical machine | |
| JPH0653020A (en) | Oxide permanent magnet |