JPS62223099A - Production of single crystal ferrite - Google Patents
Production of single crystal ferriteInfo
- Publication number
- JPS62223099A JPS62223099A JP6249286A JP6249286A JPS62223099A JP S62223099 A JPS62223099 A JP S62223099A JP 6249286 A JP6249286 A JP 6249286A JP 6249286 A JP6249286 A JP 6249286A JP S62223099 A JPS62223099 A JP S62223099A
- Authority
- JP
- Japan
- Prior art keywords
- ferrite
- oxide
- single crystal
- polycrystal
- mol
- 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
- 229910000859 α-Fe Inorganic materials 0.000 title claims abstract description 65
- 239000013078 crystal Substances 0.000 title claims abstract description 54
- 238000004519 manufacturing process Methods 0.000 title claims description 15
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 claims abstract description 32
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000000203 mixture Substances 0.000 claims abstract description 18
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 claims abstract description 16
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 claims abstract description 16
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910003437 indium oxide Inorganic materials 0.000 claims abstract description 14
- 238000010438 heat treatment Methods 0.000 claims abstract description 8
- 229910018663 Mn O Inorganic materials 0.000 claims 1
- 239000011148 porous material Substances 0.000 abstract description 19
- 239000002994 raw material Substances 0.000 abstract description 5
- 239000011787 zinc oxide Substances 0.000 abstract description 4
- 238000002156 mixing Methods 0.000 abstract 2
- 239000000463 material Substances 0.000 description 10
- 238000000034 method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 3
- 239000007791 liquid phase Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 229940110676 inzo Drugs 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
Landscapes
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は、多結晶フェライトと単結晶フェライトとを接
触加熱し、単結晶フェライトを多結晶フェライト方向に
結晶成長させて単結晶フェライトを育成する単結晶フェ
ライトの製造法に関するもので、さらに詳しくは、単結
晶フェライトの含有気孔が少なくかつ育成歩留りがよい
単結晶フェライトの製造法に関する。[Detailed Description of the Invention] (Industrial Application Field) The present invention involves contact heating of polycrystalline ferrite and single-crystal ferrite to grow single-crystal ferrite in the direction of polycrystalline ferrite to grow single-crystal ferrite. The present invention relates to a method for producing single-crystal ferrite, and more specifically, to a method for producing single-crystal ferrite that contains few pores and has a high growth yield.
(従来の技術)
従来、単結晶フェライトの製造法としてブリッヂマン法
がよく知られているが、ブリッヂマン法では単結晶用の
原料を溶融して液相から単結晶を固相として晶析させる
ため、単結晶の成長中に液相成分の変化のため、あるい
は蒸発による液相成分の変化により、均一な組成の単結
晶が得られない欠点があると共に、製造設備が大規模に
なる欠点も有していた。(Prior art) The Bridgeman method is well known as a method for producing single crystal ferrite. In the Bridgeman method, raw materials for the single crystal are melted and the single crystal is crystallized from the liquid phase as a solid phase. Therefore, there is a drawback that a single crystal with a uniform composition cannot be obtained due to changes in liquid phase components during single crystal growth or changes in liquid phase components due to evaporation, and the disadvantage is that the manufacturing equipment is large-scale. had.
このような欠点をなくするために、出願人は特公昭61
−3313号公報において、多結晶フェライト(母材)
と単結晶フェライト(種)とを接触させて加熱すること
により、種を母材に結晶成長させて育成せしめ、目的と
する単結晶フェライトを得る方法を明らにした。この方
法による単結晶フェライトは組成が均質であり、その結
果磁気特性が安定しているため、磁気ヘッド用材料とし
て優れたものである。In order to eliminate such drawbacks, the applicant has
- In Publication No. 3313, polycrystalline ferrite (base material)
We have revealed a method for obtaining the desired single-crystal ferrite by bringing the seed into contact with a single-crystal ferrite (seed) and heating it, allowing the seed to grow into crystals on the base material. Single-crystal ferrite produced by this method has a homogeneous composition and, as a result, stable magnetic properties, making it an excellent material for magnetic heads.
(発明が解決しようとする問題点)
上記の単結晶フェライトの製造法に用いられる母材は、
原料履歴がマグネタイトから製造された酸化鉄(Fez
O:+)を45〜60モル%、酸化マンガン(MnO)
20〜40モル%、酸化亜鉛(ZnO) 5〜30モル
%を成分とする多結晶フェライトである。製造された単
結晶フェライトに含有する気孔などの空孔欠陥を少くす
るためには、母材の多結晶フェライトの気孔を極力少く
しておく必要がある。多結晶フェライトは粉体の焼結に
より得られるが、焼結体の厚みが大きいほど、気孔数が
増える。このため従来の製造法では、焼結体の厚みは約
7mm以下であれば、VTR映像用ヘッドに使用可能な
気孔数とすることができるが、10mm以上では気孔が
大きくなり実用されなかった。(Problems to be solved by the invention) The base material used in the above method for producing single crystal ferrite is
The raw material history is iron oxide (Fez) manufactured from magnetite.
O: +) 45 to 60 mol%, manganese oxide (MnO)
It is a polycrystalline ferrite containing 20 to 40 mol% and zinc oxide (ZnO) 5 to 30 mol%. In order to reduce pore defects such as pores contained in the manufactured single crystal ferrite, it is necessary to minimize the pores of the polycrystalline ferrite that is the base material. Polycrystalline ferrite is obtained by sintering powder, and the greater the thickness of the sintered body, the greater the number of pores. Therefore, in the conventional manufacturing method, if the thickness of the sintered body is about 7 mm or less, it can have a number of pores that can be used in a VTR video head, but if it is 10 mm or more, the pores become too large to be put into practical use.
本発明の目的は、上記の欠点を解消し、単結晶フェライ
ト中の気孔を無くしかつ厚みの大きな単結晶フェライト
を高歩留りで得ることができる製造法を提供するにある
。SUMMARY OF THE INVENTION An object of the present invention is to provide a manufacturing method that eliminates the above-mentioned drawbacks, eliminates pores in single-crystal ferrite, and can obtain thick single-crystal ferrite at a high yield.
(問題点を解決するための手段)
本発明の単結晶フェライトの製造法は、多結晶体の端面
に単結晶のフェライトの種を接合して、加熱して多結晶
体を単結晶に成長させる単結晶フェライトの製造法にお
いて、多結晶体の組成を、酸化鉄(FezO5)45〜
60モル%、酸化マンガン(MnO)20〜40モル%
、酸化亜鉛(ZnO) 5〜30モル%からなるフェラ
イト主成分100部に対して、酸化イツトリウム(Yz
03)を0.006〜0.1部、または酸化イツトリウ
ム0.006〜0.1部および酸化インジウム(Inz
Oz)を1.0部以下添加した組成とすることを特徴と
するものである。(Means for Solving the Problems) The method for producing single crystal ferrite of the present invention involves bonding a single crystal ferrite seed to the end face of a polycrystalline body, and growing the polycrystalline body into a single crystal by heating. In the method for producing single-crystal ferrite, the composition of the polycrystal is iron oxide (FezO5) 45~
60 mol%, manganese oxide (MnO) 20-40 mol%
, yttrium oxide (Yz
0.006 to 0.1 part of 03), or 0.006 to 0.1 part of yttrium oxide and indium oxide (Inz
It is characterized by having a composition in which 1.0 part or less of oz) is added.
(作 用)
多結晶フェライトの組成を公知の酸化鉄(Pet’s)
、酸化マンガン(MnO)および酸化亜鉛(ZnO)か
らなる組成100部に対して酸化イツトリウム(YgO
s)を0.006〜0.1部または酸化イツトリウム0
.006〜0.1部および酸化インジウム(In2O3
)を1.0部以下を添加することにより、単結晶フェラ
イト中の気孔数を少なくし、磁気特性の高い単結晶フェ
ライトを得ることができる。(Function) The composition of polycrystalline ferrite is known as iron oxide (Pet's).
, yttrium oxide (YgO) per 100 parts of a composition consisting of manganese oxide (MnO) and zinc oxide (ZnO).
s) or 0.006 to 0.1 part of yttrium oxide
.. 006 to 0.1 part and indium oxide (In2O3
) by adding 1.0 parts or less of ferrite, the number of pores in the single crystal ferrite can be reduced and a single crystal ferrite with high magnetic properties can be obtained.
(実施例) 以下、本発明の詳細な説明する。(Example) The present invention will be explained in detail below.
本発明における単結晶に育成される多結晶フェライトで
ある母材の組成は、公知の酸化鉄(FezO)、酸化マ
ンガン(MnO)および酸化−亜鉛(ZnO)をそれぞ
れ45〜60モル%、20〜40モル%、5〜30モル
%とし、これらを100部として、さらに酸化イツトリ
ウム(Yz(h)を0.006〜0.1部、またはさら
に酸化インジウム(InzO:+)を0.1部以下添加
することにある。The composition of the base material, which is polycrystalline ferrite grown into a single crystal in the present invention, is 45 to 60 mol% and 20 to 60 mol% of known iron oxide (FezO), manganese oxide (MnO), and zinc oxide (ZnO), respectively. 40 mol%, 5 to 30 mol%, these are 100 parts, and further 0.006 to 0.1 part of yttrium oxide (Yz(h), or 0.1 part or less of indium oxide (InzO: +) It consists in adding.
酸化イツトリウムの量を規定する理由は、0.006部
未満では単結晶フェライト中の気孔数の減少に対して効
果が少ないためで、特に育成距離が大きい10++uw
以上の単結晶を得る場合において著しいからである。ま
た、0.1部を超えると気孔の減少には影響が少ないが
、単結晶中に真方位結晶の発生が多くなるからである。The reason for specifying the amount of yttrium oxide is that less than 0.006 parts has little effect on reducing the number of pores in single-crystal ferrite.
This is because it is significant when obtaining the above-mentioned single crystal. Moreover, if it exceeds 0.1 part, it will have little effect on the reduction of pores, but it will increase the occurrence of true-oriented crystals in the single crystal.
特に、酸化イツトリウムの量は0.006〜0.012
部が、気孔の減少に有効であるので好ましい。In particular, the amount of yttrium oxide is 0.006 to 0.012
is preferred because it is effective in reducing pores.
上記の酸化インドリウムを添加した多結晶フェライトに
対して、さらに酸化インジウム(In2O2)を1.0
部以下添加したもの、特に0.6部添加したものが、気
孔の減少に寄与するので好ましい。酸化インジウムの添
加量が1.0部を超えると、単結晶中に真方位結晶の発
生が多くなる一方、高価な材料を無駄にすることにもな
るから添加量を1.0部以下と規定する。In addition to the above polycrystalline ferrite added with indium oxide, 1.0 indium oxide (In2O2) was added.
It is preferable to add 0.6 parts or less, especially 0.6 parts, because it contributes to the reduction of pores. If the amount of indium oxide added exceeds 1.0 part, true orientation crystals will increase in the single crystal, and expensive materials will be wasted, so the amount added is specified as 1.0 part or less. do.
酸化鉄原料は、マグネタイトを経由して製造されたもの
である必要がある。The iron oxide raw material must be produced via magnetite.
また、酸化鉄、酸化マンガンおよび酸化亜鉛の組成とし
て、それぞれ52〜57モル%、25〜38モル%、9
〜22モル%が好ましい。In addition, the compositions of iron oxide, manganese oxide, and zinc oxide are 52 to 57 mol%, 25 to 38 mol%, and 9
~22 mol% is preferred.
多結晶フェライトを単結晶フェライトにする育成熱処理
は、多結晶フェライトの結晶が異常成長しない温度以下
である約1330〜1350℃から、昇温速度10℃/
時間で1430℃まで加熱して実施することが好ましい
。The growth heat treatment for converting polycrystalline ferrite into single-crystal ferrite is performed at a heating rate of 10°C/10°C from approximately 1,330 to 1,350°C, which is the temperature below which the crystals of polycrystalline ferrite do not grow abnormally.
It is preferable to carry out heating to 1430° C. for hours.
大−丘一■
マグネタイトを経由した酸化鉄、純度99.9%の酸化
マンガンおよび酸化亜鉛をそれぞれ、52.5モル%、
28モル%、19.5モル%調合した。この調合原料を
100部として、それぞれ第1表に示すように純度99
%の酸化イツトリウムおよび酸化インジウムを添加した
。Hajime Ooka ■ Iron oxide via magnetite, 52.5 mol% of manganese oxide and zinc oxide with purity of 99.9%, respectively,
28 mol% and 19.5 mol% were prepared. Assuming 100 parts of this mixed raw material, each has a purity of 99% as shown in Table 1.
% yttrium oxide and indium oxide were added.
次に、この調合物を仮焼、粉砕、成形した後、平衡酸素
分圧下で1320℃、4時間焼成して多結晶フェライト
を得た。Next, this mixture was calcined, crushed and molded, and then fired at 1320° C. for 4 hours under equilibrium oxygen partial pressure to obtain polycrystalline ferrite.
次に、この多結晶フェライトを切断、研磨加工して、表
面粗さRMAX O,05#m 、平坦度0.3μ罹で
、寸法形状が幅10mm、長さ30開で、厚さがそれぞ
れ7. 9.12ma+の多結晶フェライト母材を作成
した。Next, this polycrystalline ferrite was cut and polished to give a surface roughness of RMAX O. .. A polycrystalline ferrite base material of 9.12 ma+ was created.
この母材の幅10mm、長さ30mmの一表面に、単結
晶フェライト (種)を、地表面に例えば多結晶フェラ
イトからなるバンクダミーをそれぞれ接合した後、窒素
ガス雰囲気で1150℃、30分保持した後、昇温速度
を5℃/時間および10℃/時間で1340°Cまで昇
温し4時間保持して、多結晶フェライト母材を単結晶フ
ェライトに育成した。After bonding a single crystal ferrite (seed) to one surface of this base material with a width of 10 mm and a length of 30 mm, and a bank dummy made of, for example, polycrystalline ferrite to the ground surface, they were held at 1150°C for 30 minutes in a nitrogen gas atmosphere. After that, the temperature was raised to 1340°C at a temperature increase rate of 5°C/hour and 10°C/hour and held for 4 hours to grow the polycrystalline ferrite base material into single crystal ferrite.
このようにして得られた単結晶フェライトをその育成方
向に平行な面を研磨して、光学顕微鏡で1μ−以上の気
孔径の数を計数し単位面積当りの数をもって気孔率を求
めると共に、実方位結晶の存在を観察し、異方位結晶相
が単結晶フェライトの外表面から2mm以内に存在する
ものを不良として育成歩留りを求めた。その結果を第1
表に示す。The single-crystal ferrite thus obtained was polished on the surface parallel to its growth direction, and the number of pores with a diameter of 1μ or more was counted using an optical microscope to determine the porosity based on the number per unit area. The presence of oriented crystals was observed, and the growth yield was determined by determining the presence of differently oriented crystal phases within 2 mm from the outer surface of the single crystal ferrite as defective. The result is the first
Shown in the table.
第1表の結果から明らかなように、本発明の組成の多結
晶フェライトは、気孔数が少なくその結果磁気特性が良
好であると共に高歩留りが達成できるのに対し、本発明
外の組成を有する多結晶フェライトから得た比較例では
気孔数が大きく、良好なものは得られなかった。As is clear from the results in Table 1, polycrystalline ferrite having a composition according to the present invention has a small number of pores, resulting in good magnetic properties and a high yield, whereas polycrystalline ferrite having a composition other than the present invention can achieve good magnetic properties and high yield. In the comparative example obtained from polycrystalline ferrite, the number of pores was large, and a good one could not be obtained.
(発明の効果)
以上詳細に説明したとこから明らかなように、本発明の
単結晶フェライトの製造法によれば、多結晶体の組成を
酸化マンガン、酸化亜鉛、酸化インドリウムからなるフ
ェライト主成分100部に対して酸化インドリウムを0
.006〜0.1部またはさらに酸化インジウム1.0
部以下を添加した組成とすることにより、気孔数が少な
くその結果磁気特性が良好な単結晶フェライトを高歩留
りで得ることができる。(Effects of the Invention) As is clear from the above detailed explanation, according to the method for producing single crystal ferrite of the present invention, the composition of the polycrystalline body is changed to a ferrite main component consisting of manganese oxide, zinc oxide, and indium oxide. 0 indium oxide per 100 parts
.. 0.06 to 0.1 part or even 1.0 part of indium oxide
By adding less than 30% of the total number of pores, single crystal ferrite with a small number of pores and good magnetic properties can be obtained at a high yield.
Claims (1)
て、加熱して多結晶体を単結晶に成長させる単結晶フェ
ライトの製造法において、多結晶体の組成を、酸化鉄(
Fe_2O_3)45〜60モル%、酸化マンガン(M
nO)20〜40モル%、酸化亜鉛(ZnO)5〜30
モル%からなるフェライト主成分100部に対して、酸
化イットリウム(Y_2O_3)を0.006〜0.1
部添加した組成とすることを特徴とする単結晶フェライ
トの製造法。 2、多結晶体の端面に単結晶のフェライトの種を接合し
て、加熱して多結晶体を単結晶に成長させる単結晶フェ
ライトの製造法において多結晶体の組成を、酸化鉄(F
e_2O_3)45〜60モル%、酸化マンガン(Mn
O)20〜40モル%、酸化亜鉛(ZnO)5〜30モ
ル%からなるフェライト主成分100部に対して、酸化
イットリウム(Y_2O_3)を0.006〜0.1部
および酸化インジウム(In_2O_3)を1.0部以
下添加した組成とすることを特徴とする単結晶フェライ
トの製造法。[Claims] 1. A method for producing single-crystal ferrite in which a single-crystal ferrite seed is bonded to the end face of a polycrystal and the polycrystal is grown into a single crystal by heating, the composition of the polycrystal being , iron oxide (
Fe_2O_3) 45-60 mol%, manganese oxide (M
nO) 20-40 mol%, zinc oxide (ZnO) 5-30
0.006 to 0.1 yttrium oxide (Y_2O_3) to 100 parts of ferrite main component consisting of mol%
A method for producing single-crystal ferrite, characterized in that it has a composition in which part of it is added. 2. In the manufacturing method of single crystal ferrite, in which a single crystal ferrite seed is bonded to the end face of a polycrystal and heated to grow the polycrystal into a single crystal, the composition of the polycrystal is changed to iron oxide (F).
e_2O_3) 45-60 mol%, manganese oxide (Mn
O) 0.006 to 0.1 part of yttrium oxide (Y_2O_3) and indium oxide (In_2O_3) to 100 parts of the ferrite main component consisting of 20 to 40 mol% and 5 to 30 mol% of zinc oxide (ZnO). A method for producing single crystal ferrite, characterized in that the composition is such that 1.0 part or less is added.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6249286A JPS62223099A (en) | 1986-03-20 | 1986-03-20 | Production of single crystal ferrite |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6249286A JPS62223099A (en) | 1986-03-20 | 1986-03-20 | Production of single crystal ferrite |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS62223099A true JPS62223099A (en) | 1987-10-01 |
Family
ID=13201722
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP6249286A Pending JPS62223099A (en) | 1986-03-20 | 1986-03-20 | Production of single crystal ferrite |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS62223099A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5629100A (en) * | 1992-11-20 | 1997-05-13 | Ngk Insulators, Ltd. | Non-magnetic single crystal Mn--Zn ferrite for floating type magnetic heads |
-
1986
- 1986-03-20 JP JP6249286A patent/JPS62223099A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5629100A (en) * | 1992-11-20 | 1997-05-13 | Ngk Insulators, Ltd. | Non-magnetic single crystal Mn--Zn ferrite for floating type magnetic heads |
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