JPS6215517B2 - - Google Patents
Info
- Publication number
- JPS6215517B2 JPS6215517B2 JP57132731A JP13273182A JPS6215517B2 JP S6215517 B2 JPS6215517 B2 JP S6215517B2 JP 57132731 A JP57132731 A JP 57132731A JP 13273182 A JP13273182 A JP 13273182A JP S6215517 B2 JPS6215517 B2 JP S6215517B2
- Authority
- JP
- Japan
- Prior art keywords
- ferrite
- crystal
- polycrystalline
- single crystal
- coprecipitated
- 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.)
- Expired
Links
- 229910000859 α-Fe Inorganic materials 0.000 claims description 111
- 239000013078 crystal Substances 0.000 claims description 72
- 238000000034 method Methods 0.000 claims description 27
- 239000000843 powder Substances 0.000 claims description 23
- 239000002245 particle Substances 0.000 claims description 21
- 239000000203 mixture Substances 0.000 claims description 14
- 238000004519 manufacturing process Methods 0.000 claims description 11
- 239000007858 starting material Substances 0.000 claims description 7
- 238000010304 firing Methods 0.000 claims description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 19
- 238000002425 crystallisation Methods 0.000 description 14
- 230000008025 crystallization Effects 0.000 description 14
- 239000002994 raw material Substances 0.000 description 14
- 238000002156 mixing Methods 0.000 description 12
- 238000010438 heat treatment Methods 0.000 description 11
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000006061 abrasive grain Substances 0.000 description 6
- 229910052742 iron Inorganic materials 0.000 description 6
- 238000000465 moulding Methods 0.000 description 6
- 239000011148 porous material Substances 0.000 description 6
- 239000011701 zinc Substances 0.000 description 6
- 238000001354 calcination Methods 0.000 description 5
- 229910002588 FeOOH Inorganic materials 0.000 description 4
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- 239000010432 diamond Substances 0.000 description 4
- 229910003460 diamond Inorganic materials 0.000 description 4
- 238000007731 hot pressing Methods 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- 229910001566 austenite Inorganic materials 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 238000005469 granulation Methods 0.000 description 3
- 230000003179 granulation Effects 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 101100513612 Microdochium nivale MnCO gene Proteins 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000000975 co-precipitation Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000005204 segregation Methods 0.000 description 2
- 238000003746 solid phase reaction Methods 0.000 description 2
- 239000011029 spinel Substances 0.000 description 2
- 229910052596 spinel Inorganic materials 0.000 description 2
- 229910013641 LiNbO 3 Inorganic materials 0.000 description 1
- 229910003174 MnOOH Inorganic materials 0.000 description 1
- 241000080590 Niso Species 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000007716 flux method Methods 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 238000001027 hydrothermal synthesis Methods 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 235000014413 iron hydroxide Nutrition 0.000 description 1
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 description 1
- 238000005304 joining Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011812 mixed powder Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000012856 weighed raw material Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 229910006540 α-FeOOH Inorganic materials 0.000 description 1
- 229910006299 γ-FeOOH Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B1/00—Single-crystal growth directly from the solid state
- C30B1/02—Single-crystal growth directly from the solid state by thermal treatment, e.g. strain annealing
Landscapes
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Engineering & Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Compounds Of Iron (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
【発明の詳細な説明】
本発明は、単結晶フエライトの製造法に関する
もので、その目的は、従来の単結晶フエライト製
造法に比べて組成偏析が少なく、均質で制御され
た結晶方位を有する単結晶を、高歩留りで多量に
生産する方法を提供することにある。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing single-crystal ferrite, and its purpose is to produce a single-crystal ferrite having less compositional segregation and a homogeneous and controlled crystal orientation compared to conventional methods for producing single-crystal ferrite. An object of the present invention is to provide a method for producing crystals in large quantities with high yield.
現在、酸化物系単結晶は、磁気記録用磁気ヘツ
ド材料のMn−Znフエライト単結晶、水晶発振素
子、レーザー用YAG単結晶、センサー用LiNbO3
単結晶等、電子工業の分野で多数使われている。
従来の単結晶製造法には、チヨクラルスキー法、
ブリツジマン法、ベルヌーイ法、フラツクス法、
水熱合成法、高温高圧反応法等各種の方法があ
る。 Currently, oxide-based single crystals include Mn-Zn ferrite single crystals for magnetic head materials for magnetic recording, YAG single crystals for crystal oscillation elements, lasers, and LiNbO 3 for sensors.
Single crystals are widely used in the electronic industry.
Conventional single crystal manufacturing methods include the Czyochralski method,
Bridgeman method, Bernoulli method, flux method,
There are various methods such as hydrothermal synthesis method and high temperature high pressure reaction method.
これらの技術は、単結晶育成に相当な時間がか
かり、かつ得られた単結晶内部に、組成の偏析、
クラツクの発生、インゴツトが１つの単結晶にな
らずに複数個のものになる多結晶があり、良品の
歩留り率が低く、解決されなければならない問題
が多く残されている。 These techniques require a considerable amount of time to grow single crystals, and the resulting single crystals suffer from compositional segregation and
There are cracks, polycrystalline ingots do not become one single crystal, but multiple ingots, the yield rate of good products is low, and many problems remain to be solved.
本発明は、これら従来からなる単結晶体の製造
法とは異なつた、固相反応による単結晶体の育成
法、すなわち、所望の単結晶フエライトと、この
単結晶フエライトと同組成もしくはそれに近い組
成で、同じ結晶構造を有する多結晶フエライトと
を接合し、この接合体を熱処理することにより、
多結晶フエライトを単結晶フエライトと同じ結晶
方位と結晶構造をもつ単結晶フエライトに育成す
る単結晶フエライトの製造法（以後、「接合型単
結晶フエライトの製造法」と呼ぶ）において湿式
法で合成された共沈フエライト粉体を出発原料と
し、これを焼成した多結晶フエライトを単結晶化
させる出発多結晶体として用いることを特徴とす
る単結晶フエライトの製造法である。 The present invention provides a method for growing a single crystal by solid-phase reaction, which is different from these conventional methods for producing a single crystal. By joining polycrystalline ferrite with the same crystal structure and heat-treating this joined body,
Synthesized by a wet method in the single-crystal ferrite manufacturing method (hereinafter referred to as the "junction type single-crystal ferrite manufacturing method") in which polycrystalline ferrite is grown into single-crystal ferrite with the same crystal orientation and crystal structure as single-crystal ferrite. This is a method for producing single crystal ferrite, which is characterized in that a coprecipitated ferrite powder is used as a starting material and used as a starting polycrystal for monocrystallizing a fired polycrystalline ferrite.
さらに、発明者等は、湿式法で合成される共沈
フエライト粉体について、その平均粒径が単結晶
化に及ぼす影響を調べた。その結果、本発明で用
いる共沈フエライト粉体は平均粒径0.01〜1.0μ
ｍの範囲のものが適していることが判明した。 Furthermore, the inventors investigated the influence of the average particle size on single crystallization of coprecipitated ferrite powder synthesized by a wet method. As a result, the coprecipitated ferrite powder used in the present invention has an average particle size of 0.01 to 1.0μ.
It has been found that a range of m is suitable.
以下、本発明の方法について、さらに詳しく説
明する。 The method of the present invention will be explained in more detail below.
第１図は、本発明で用いる単結晶フエライトと
多結晶フエライトとの接合体を模式的に示したも
ので、同図Ａは熱処理前のもの、同図Ｂは適当な
熱処理後の接合体を示している。Ａ−１は種子に
使う単結晶フエライト、Ａ−２は単結晶フエライ
ト化しようとする多結晶フエライト、Ａ−３は、
単結晶フエライトと多結晶フエライトの接合界面
である。Ｂ−１はＡ−１と同じ種子単結晶フエラ
イト、Ｂ−２はまだ単結晶化していない多結晶フ
エライト、Ｂ−３は最初、熱処理前接合界面のあ
つた位置、Ｂ−４は多結晶フエライトから単結晶
フエライトに変つた部分（単結晶化した部分）、
Ｂ−５は単結晶フエライト化した領域と多結晶の
境界（界面）である。ＬはＢ−３の位置から界面
Ｂ−５まで測つた単結晶化した長さである。本発
明で用いる多結晶フエライトは、一般に接合界面
Ａ−３，Ｂ−５の多結晶フエライト側へ移動がス
ムーズに行なわれるように、小粒径で、不純物が
少なく、気孔のほとんどないものが望ましい。つ
まり小粒径であればある程、接合界面が単結晶側
に移動するために受ける駆動力が大きい。一方、
異相の析出物、気孔等は界面が移動するときの抵
抗として働くため、これらが少なければ少ない
程、単結晶フエライト化しやすい。 Figure 1 schematically shows a bonded body of single-crystal ferrite and polycrystalline ferrite used in the present invention. Figure A shows the bonded body before heat treatment, and Figure B shows the bonded body after appropriate heat treatment. It shows. A-1 is a single-crystal ferrite used for seeds, A-2 is a polycrystalline ferrite that is to be made into a single-crystal ferrite, and A-3 is a
This is the bonding interface between single-crystal ferrite and polycrystalline ferrite. B-1 is the same seed single-crystal ferrite as A-1, B-2 is polycrystalline ferrite that has not yet become a single crystal, B-3 is the initial position of the bonding interface before heat treatment, and B-4 is polycrystalline ferrite. The part that changed from to single crystal ferrite (the part that became single crystal),
B-5 is the boundary (interface) between the single crystal ferrite region and the polycrystal. L is the single crystallized length measured from the position of B-3 to the interface B-5. In general, the polycrystalline ferrite used in the present invention preferably has a small grain size, contains few impurities, and has almost no pores so that the polycrystalline ferrite can smoothly move toward the polycrystalline ferrite side of the bonding interfaces A-3 and B-5. . In other words, the smaller the grain size, the greater the driving force received to move the bonding interface toward the single crystal. on the other hand,
Different phase precipitates, pores, etc. act as resistance when the interface moves, so the less they are present, the easier it is to form a single crystal ferrite.
発明者等は、この接合型単結晶フエライトの製
造法において、短時間にいかに効率よく均質な単
結晶フエライトを、高い歩留りで育成するかにつ
いて種々検討した。その結果、単結晶多結晶体の
セラミツクス的特性すなわち多結晶を構成する結
晶粒の形状、粒径、粒径分布、気孔率、気孔の形
状、気孔の分布個所、粒界の形状、粒界層の厚さ
等の性質およびフエライトとしての電磁気特性を
決定する主要因子である出発原料粉体の選択が非
常に重要であるという知見から、多数の種類の原
料粉体の組み合わせを作り、これを用いて焼成し
た多結晶フエライトを準備し、これでもつて接合
型単結晶の実験を行なつた。出発原料粉の組み合
わせる方法として、混合系と非混合系の二種があ
る。混合系は各種の酸化物、水酸化物、炭酸塩等
を混合し、焼成してフエライト化させるものであ
り、非混合系は最初からフエライト化しているも
のである。混合系として、水酸化鉄（α−
FeOOH、γ−FeOOH）、立方晶系酸化鉄（γ−
Fe2O3、Fe3O4）、六方晶系酸化鉄（α−
Fe2O3）、炭酸マンガン（MnCO3）、水酸化マン
ガン（γ−MnOOH）、酸化亜鉛（ZnO）の中か
ら最終組成がFe2O350モル％、MnO25モル％、
ZnO25モル％になるように、鉄やマンガン、亜鉛
の種々の原料を秤量して用い、非混合系では、湿
式法で作製された前述のものと同組成の共沈フエ
ライトを用いる。多結晶体として、混合系では、
秤量された配合原料を、ステンレス鋼製ボールミ
ルで湿式混合し、仮焼してから、再度ボールミル
で湿式混合した。混合後、乾燥し、造粒、成形を
行ない、これを1250℃〜1300℃の範囲内の温度で
ホツトプレス（300Kg／cm2、３時間）し、結晶粒
径が10〜20μｍのものを作製した。一方、非混合
系の共沈フエライトを用いた場合には、混合系の
工程のうち、最初の配合、湿式混合工程のみを省
いた、残余の工程に従つて、多結晶フエライトを
作製した。共沈フエライトから作製した多結晶フ
エライトは、混合系の他の原料粉を用いて作製し
た多結晶フエライトに比べてその内部に残存する
気孔が少なく、気孔率が約1/3〜1/5になり、かつ
気孔の最大値径も0.1μｍ以下と小さなものにな
る。また、湿式法で合成された共沈原料は、混合
系の原料粉体に比べて不純物の含有量が少ない。
特に多結晶フエライトの結晶粒界に析出しやすい
CaOとSiO2については、含有量の少ない共沈フ
エライトを比較的容易に合成、製造ができるの
で、高純度原料を低コストで得られるという点で
も優れたものである。また、一般に、共沈フエラ
イト粉体を焼成して作つた多結晶フエライトは、
同一製造条件で作つた混合系粉体を焼成した多結
晶フエライトに比べて10％〜数10％小さい結晶粒
径のものが得られる。このことは、単結晶化する
場合には、界面移動のための駆動力が大きくなる
ので、好ましいものである。これらの性質すなわ
ち高密度（気孔率小）、小粒径で、粒界析出物が
少ないという性質は、本発明で用いる多結晶フエ
ライトとして望ましい特性である。 The inventors conducted various studies on how to efficiently grow homogeneous single crystal ferrite in a short period of time with a high yield in this method for manufacturing bonded single crystal ferrite. As a result, the ceramic properties of single-crystalline polycrystals, namely the shape, grain size, grain size distribution, porosity, shape of pores, location of distribution of pores, shape of grain boundaries, and grain boundary layer, are determined. Based on the knowledge that the selection of the starting raw material powder is very important as it is the main factor that determines the properties such as the thickness of the ferrite and the electromagnetic properties of the ferrite, we created a combination of many types of raw material powder and used it. We prepared a polycrystalline ferrite fired using the same method, and conducted experiments on bonded single crystals using it. There are two methods for combining starting material powders: a mixed system and a non-mixed system. Mixed systems are those in which various oxides, hydroxides, carbonates, etc. are mixed and fired to form ferrite, while non-mixed systems are those in which ferrite is formed from the beginning. As a mixed system, iron hydroxide (α-
FeOOH, γ-FeOOH), cubic iron oxide (γ-
Fe 2 O 3 , Fe 3 O 4 ), hexagonal iron oxide (α-
The final composition is Fe 2 O 3 50 mol%, MnO 25 mol % ,
Various raw materials such as iron, manganese, and zinc are weighed and used so that ZnO is 25 mol %, and in a non-mixed system, coprecipitated ferrite with the same composition as the above-mentioned one produced by a wet method is used. As a polycrystal, in a mixed system,
The weighed raw materials were wet-mixed in a stainless steel ball mill, calcined, and wet-mixed again in a ball mill. After mixing, the mixture was dried, granulated and molded, and then hot pressed (300Kg/cm 2 , 3 hours) at a temperature within the range of 1250°C to 1300°C to produce crystal grains with a crystal grain size of 10 to 20 μm. . On the other hand, when a non-mixing coprecipitated ferrite was used, polycrystalline ferrite was produced by following the remaining steps of the mixing system, excluding only the initial blending and wet mixing steps. Polycrystalline ferrite made from coprecipitated ferrite has fewer pores remaining inside it than polycrystalline ferrite made using other mixed raw material powders, and the porosity is about 1/3 to 1/5. In addition, the maximum diameter of the pores is as small as 0.1 μm or less. In addition, coprecipitated raw materials synthesized by a wet method have a lower content of impurities than mixed raw material powders.
Particularly easy to precipitate at grain boundaries of polycrystalline ferrite.
Regarding CaO and SiO 2 , co-precipitated ferrite with a low content can be synthesized and produced relatively easily, so it is also excellent in that high-purity raw materials can be obtained at low cost. In general, polycrystalline ferrite made by firing coprecipitated ferrite powder is
Compared to polycrystalline ferrite produced by firing a mixed powder produced under the same manufacturing conditions, crystal grain sizes 10% to several 10% smaller can be obtained. This is preferable in the case of single crystallization because the driving force for interfacial movement becomes large. These properties, namely high density (low porosity), small grain size, and few grain boundary precipitates, are desirable properties for the polycrystalline ferrite used in the present invention.
本発明でいう、湿式法で合成される共沈フエラ
イト粉体は、Fe2+、M2+（＝Mn2+、Ni2+、
Zn2+、CO2+、Mg2+………等）を含む塩を所望の
組成になるようにして配合し、水溶液にして、こ
れにアルカリを添加し中性化して沈降させ、沈降
時に液を撹拌し酸素を吹き込んだり、熟成等を行
なつたりして、粒径を制御して得られるものであ
る。 In the present invention, the coprecipitated ferrite powder synthesized by the wet method contains Fe 2+ , M 2+ (=Mn 2+ , Ni 2+ ,
Salts containing Zn 2+ , CO 2+ , Mg 2+ , etc.) are blended to the desired composition, made into an aqueous solution, and an alkali is added to neutralize and settle. It is obtained by controlling the particle size by stirring the liquid, blowing oxygen into it, aging it, etc.
このようにして混合系、非混合系から焼成して
得られたこれらの多結晶フエライトを30×15×20
mm３の大きさに切断し、30×15mm2の接合面を粒度
2000番、4000番のSiC砥粒、ダイヤモンド砥粒
（３μｍ径）にて鏡面にまで仕上げた。ほぼ同組
成のMn−Zn−Feフエライト単結晶を（100）面
が30×15mm2の接合面になるように結晶方位を確か
めて、1.5mm〜1.7mmの厚さに切断し、多結晶フエ
ライトと同様に、接合面を鏡面に仕上げた。多結
晶フエライトと単結晶フエライト双方の接合面
に、希硝酸を塗布した後、両者を貼り合わせ、こ
れを、N2ガスを流した電気炉内にて1250℃で30
分、続いて1300℃で３時間、30Kg／cm2でホツトプ
レスし、接合界面の固相反応と多結晶フエライト
の単結晶化熱処理を行なつた。熱処理後、接合体
を、接合界面と垂直な方向に中央部を切断し、切
断面を、2000番、4000番のSiC砥粒でラツプし、
さらに粒径３μｍのダイヤモンド砥粒で鏡面ラツ
プした後、熱濃リン酸でエツチングを行ない、単
結晶化距離（第１図ＢのＬ）を測定した。 These polycrystalline ferrites obtained by firing the mixed and non-mixed systems in this way are 30×15×20
Cut to a size of mm 3 , and the joint surface of 30 x 15 mm 2
Finished to a mirror finish using No. 2000 and No. 4000 SiC abrasive grains and diamond abrasive grains (3 μm diameter). A Mn-Zn-Fe ferrite single crystal with almost the same composition was cut into polycrystalline ferrite by checking the crystal orientation so that the (100) plane was a 30 x 15 mm 2 joint surface and cutting it into a thickness of 1.5 mm to 1.7 mm. Similarly, the joint surfaces were finished to a mirror finish. After applying dilute nitric acid to the joint surfaces of both polycrystalline ferrite and single crystal ferrite, they were bonded together and heated at 1250℃ for 30 minutes in an electric furnace with N2 gas flowing.
Then, hot pressing was carried out at 1300° C. for 3 hours at 30 kg/cm 2 to perform a solid phase reaction at the bonding interface and a heat treatment for single crystallization of the polycrystalline ferrite. After heat treatment, the bonded body was cut at the center in a direction perpendicular to the bonding interface, and the cut surface was wrapped with No. 2000 and No. 4000 SiC abrasive grains.
Further, after mirror-lapping with diamond abrasive grains having a grain size of 3 μm, etching was performed with hot concentrated phosphoric acid, and the single crystallization distance (L in FIG. 1B) was measured.
これらの一連の実験の結果、非混合系の共沈フ
エライトを出発原料粉末として焼成して作製した
多結晶フエライトを用いたものが、単結晶化距離
Ｌがいちじるしく大きく、混合系のもの（全然界
面が移動しないものから移動しても、最大約３
mm）に比べて約３〜５倍の12mm以上であり、また
単結晶体化したものの電磁気特性も優れたものが
得られ、本発明においては、最も好ましいもので
あつた。よつて、本発明で用いる多結晶として、
共沈フエライトを出発原料粉体として焼成された
多結晶を用いることが望ましい。 As a result of these series of experiments, the single crystallization distance L was significantly larger in the polycrystalline ferrite produced by firing non-mixed co-precipitated ferrite as a starting material powder, and the mixed type (with no interface at all). Even if it moves from something that does not move, the maximum is about 3
The diameter was 12 mm or more, which is about 3 to 5 times larger than that in mm), and a single crystal with excellent electromagnetic properties was obtained, which was the most preferable in the present invention. Therefore, as the polycrystal used in the present invention,
It is desirable to use polycrystals fired from coprecipitated ferrite as a starting material powder.
さらに、発明者等は、共沈フエライト粉体につ
いて、どのように粒径のものが、接合型単結晶フ
エライトの多結晶として適しているかを調べた。
共沈フエライト粉体として、粒径が0.005μｍ程
度のものから、最大数μｍのものまで合成できる
が、本発明で用いる高密度、小粒径で粒界析出物
の少ない多結晶の原料粉体としては、製造時の取
り扱いよさ、および単結晶化しやすいか否かにつ
いて検討したところ、単結晶化しやすいというこ
とから、粒径が0.01〜1.0μｍのものが好まし
く、さらに0.1〜0.7μｍのものがより好ましい。 Furthermore, the inventors investigated what particle size of coprecipitated ferrite powder is suitable as a polycrystal of bonded single crystal ferrite.
Co-precipitated ferrite powder can be synthesized from particle sizes of about 0.005 μm to a maximum of several μm, but the polycrystalline raw material powder used in the present invention has high density, small particle size, and few grain boundary precipitates. After considering the ease of handling during manufacturing and whether or not it is easy to form a single crystal, we found that particles with a particle size of 0.01 to 1.0 μm are preferable, and those with a particle size of 0.1 to 0.7 μm are preferable because they are easy to form a single crystal. More preferred.
そして、本発明の方法は、Mn−Znフエライト
だけでなく、Ni−Zn−Feフエライト等のフエラ
イト一般に適用することができる。 The method of the present invention can be applied not only to Mn-Zn ferrite but also to ferrites in general such as Ni-Zn-Fe ferrite.
以下、本発明の実施例について詳細に説明す
る。 Examples of the present invention will be described in detail below.
実施例 １
最終組成比が52モル％Fe2O3、32モル％MnO、
16モル％ZnOになるように、純度99.5％のα−
Fe2O3182.5ｇと、含有量91.2％のMnCO388.7ｇ
と、純度99.8％のZnO28.7ｇを秤量し、ステンレ
スボールミルにて湿式で15時間混合し、混合後
900℃で２時間空気中で仮焼した。仮焼後、再度
ステンレスボールミルで15時間湿式混合し、その
後その泥状物を130℃で10時間乾燥した。純水を
12〜15％加えてらいかい器にて造粒し、粒度をそ
ろえた後、300Kg／cm2の成形圧で造粒粉を成形し
た。この成形体を空気中にて1280℃で３時間、
300Kg／cm2の圧力下でホツトプレスして焼結体を
得た。次に、52モル％Fe2O3、32モル％MnO、16
モル％ZnOの組成を有する平均粒径が0.1μｍ共
沈フエライト（FeSO4、MnSO4、ZnSO4溶液に
NaOHを加えて共沈させたものを、900℃で２時
間空気中で仮焼し、仮焼後、前述と同様にステン
レスボールミルにて湿式混合・乾燥・造粒成形工
程を経てほぼ同様な条件でホツトプレス焼成を行
い、平均結晶粒径20μｍ、気孔率0.01％の焼結体
を得た。これら二種類の多結晶フエライトを30×
15×20mm３にダイヤモンドカツターで切断し、30
×15mm2の面を接合面とし、この面を順次2000番、
4000番SiC砥粒にてラツプし、３μｍ径のダイヤ
モンド砥粒で鏡面にまで仕上げた。一方、この多
結晶フエライトと同組成のMn−Znフエライト単
結晶の（100）面を30×15mm2の面にし、二つの側
面を（110）とした厚さ1.5mmの単結晶板に切断
し、多結晶フエライトと同様に30×15mm2の面を、
接合面として鏡面にまで仕上げた。単結晶、多結
晶双方の接合面に1N−HNO3を塗布し、単結晶フ
エライトを種類の異なる多結晶フエライトに張り
合わせ、二種類の接合体を作製した。この二種類
の接合体を、N2ガスを流した雰囲気中にて1320
℃で３時間、30Kg／cm2の圧力でホツトプレスし、
接合体の多結晶フエライトの単結晶化を行なつ
た。このホツトプレス熱処理後、接合体試料を、
接合界面に垂直に中央部で切断し、切断面を鏡面
に仕上げた後、80℃濃リン酸にて表面をエツチン
グし、単結晶化長さＬを測定した。共沈フエライ
トを出発原料に用いた多結晶の接合体ではＬ＝８
mmであつたが、α−Fe2O3、MnCO3、ZnOを出発
原料に用いた多結晶の接合体ではＬ＝0.5mmであ
つた。共沈多結晶の単結晶化した部分の磁気特性
を測定すると、1KHzでの透磁率（μ）がμ＝
10000で、抗磁力（Hc）はHc＝0.05（Oe）であ
つた。この値は、従来のブリツジマン法で作製さ
れた同組成のMn−Znフエライトのそれと同じも
のであつた。Example 1 Final composition ratio: 52 mol% Fe 2 O 3 , 32 mol% MnO,
99.5% pure α- to give 16 mol% ZnO
182.5 g of Fe 2 O 3 and 88.7 g of MnCO 3 with a content of 91.2%
Weighed 8.7g of ZnO2 with a purity of 99.8% and mixed them wet in a stainless steel ball mill for 15 hours.
It was calcined in air at 900°C for 2 hours. After calcining, wet mixing was carried out again in a stainless steel ball mill for 15 hours, and then the slurry was dried at 130°C for 10 hours. pure water
After adding 12 to 15% of the powder and granulating it in a miller to make the particle size uniform, the granulated powder was molded at a molding pressure of 300 kg/cm 2 . This molded body was heated in air at 1280℃ for 3 hours.
A sintered body was obtained by hot pressing under a pressure of 300 kg/cm 2 . Then 52 mol% Fe2O3 , 32 mol% MnO, 16
Co-precipitated ferrite with an average particle size of 0.1 μm with a composition of mol% ZnO (FeSO 4 , MnSO 4 , ZnSO 4 solution)
The co-precipitated product with NaOH was calcined in air at 900℃ for 2 hours, and after calcining, it was subjected to wet mixing, drying, and granulation molding processes in a stainless steel ball mill as described above under almost the same conditions. Hot press firing was performed to obtain a sintered body with an average grain size of 20 μm and a porosity of 0.01%. These two types of polycrystalline ferrite are 30×
Cut into 15×20mm 3 pieces with a diamond cutter, 30
The surface of ×15mm 2 is used as the joint surface, and this surface is sequentially bonded with No. 2000,
It was lapped with No. 4000 SiC abrasive grains and finished to a mirror finish with 3 μm diameter diamond abrasive grains. On the other hand, a Mn-Zn ferrite single crystal with the same composition as this polycrystalline ferrite was cut into a 1.5 mm thick single crystal plate with the (100) plane as a 30 x 15 mm 2 plane and two sides as (110). , a surface of 30 x 15 mm 2 as well as polycrystalline ferrite,
The joint surface has been finished to a mirror finish. 1N-HNO 3 was applied to the joint surfaces of both the single crystal and polycrystal, and the single crystal ferrite was bonded to different types of polycrystal ferrite to produce two types of joined bodies. These two types of bonded bodies were heated at 1320 °C in an atmosphere flowing N2 gas.
Hot pressed at a pressure of 30Kg/ cm2 for 3 hours at ℃,
The polycrystalline ferrite of the bonded body was single-crystallized. After this hot press heat treatment, the joined body sample was
After cutting at the center perpendicular to the bonding interface and finishing the cut surface with a mirror finish, the surface was etched with concentrated phosphoric acid at 80°C and the single crystallization length L was measured. In a polycrystalline composite using coprecipitated ferrite as a starting material, L = 8.
mm, but in the case of a polycrystalline bonded body using α-Fe 2 O 3 , MnCO 3 , and ZnO as starting materials, L=0.5 mm. When measuring the magnetic properties of the single crystallized part of the coprecipitated polycrystal, the magnetic permeability (μ) at 1KHz is μ=
10,000, and the coercive force (Hc) was Hc = 0.05 (Oe). This value was the same as that of Mn-Zn ferrite of the same composition produced by the conventional Bridgeman method.
実施例 ２
前述の六方晶α−Fe2O3を立方晶スピネル構造
のγ−Fe2O3および、Fe3O4に変え、他の原料は
同じである、52モル％Fe2O3、36モル％MnO、16
モル％ZnOの多結晶体を、実施例１と同様にして
秤量し混合して、800℃で２時間、空気中におい
て仮焼した。仮焼後、再度湿式混合し、乾燥、造
粒、成形後（成形圧300Kg／cm2）、1250℃で３時
間、300Kg／cm2でホツトプレス焼結を行ない、平
均結晶粒径15μｍ気孔率0.02％の焼結体を得た。
実施例１で用いた共沈フエライトを、最初の混合
以外、全て同じ条件で製造してホツトプレス焼結
体を得た。平均結晶粒径は10μｍ、気孔率は0.01
％であつた。これら三者の多結晶フエライトを用
いて実施例１と同様に接合体を作製し、N2中に
てホツトプレス熱処理を行なつた。単結晶化長さ
Ｌを測定すると、γ−Fe2O3を用いたものではＬ
＝1.5mm、Fe3O4を用いたものでは、Ｌ＝2.5mm、
共沈フエライトを用いたものではＬ＝8.5mmであ
つた。Example 2 The aforementioned hexagonal α-Fe 2 O 3 was changed to γ-Fe 2 O 3 and Fe 3 O 4 with a cubic spinel structure, and the other raw materials were the same, 52 mol% Fe 2 O 3 , 36 mol% MnO, 16
Polycrystals of mol % ZnO were weighed and mixed in the same manner as in Example 1, and calcined in air at 800° C. for 2 hours. After calcination, wet mixing again, drying, granulation, and molding (molding pressure 300Kg/cm 2 ), followed by hot press sintering at 1250℃ for 3 hours at 300Kg/cm 2 to obtain an average crystal grain size of 15 μm and a porosity of 0.02. % sintered body was obtained.
The coprecipitated ferrite used in Example 1 was manufactured under the same conditions except for the initial mixing to obtain a hot-pressed sintered body. Average grain size is 10μm, porosity is 0.01
It was %. A bonded body was prepared using these three polycrystalline ferrites in the same manner as in Example 1, and hot press heat treatment was performed in N 2 . When the single crystallization length L is measured, it is L for the one using γ-Fe 2 O 3 .
= 1.5mm, for the one using Fe 3 O 4 , L = 2.5mm,
In the case of using coprecipitated ferrite, L was 8.5 mm.
多結晶フエライトの結晶粒径と気孔率の影響を
考慮するため、ホツトプレス温度を20〜30℃高
め、ホツトプレス圧力を下げて、共沈フエライト
焼結体を作り、結晶粒径15μｍ、気孔率0.02％の
ものを得た。この多結晶を用いてN2中ホツトプ
レス熱処理により単結晶化させたところ、単結晶
化長さＬは8.0mmであつた。 In order to take into account the influence of the crystal grain size and porosity of polycrystalline ferrite, the hot press temperature was increased by 20 to 30°C and the hot press pressure was lowered to produce a coprecipitated ferrite sintered body, with a crystal grain size of 15 μm and a porosity of 0.02%. I got something. When this polycrystal was single-crystalized by hot press heat treatment in N 2 , the single-crystal length L was 8.0 mm.
実施例 ３
最終組成が50モル％Fe2O3、25モル％MnO、25
モル％ZnOになるように、酸化鉄になる原料とし
て含有率95％のα−FeOOH、および同じくγ−
FeOOHをそれぞれ187.1ｇを使用し、酸化マンガ
ンになる原料として含有率95％のγ−
MnOOH46.3ｇを使用し、これらと純度99.5％の
ZnO40.88ｇを秤量、配合して混合した後、800℃
で２時間、空気中において仮焼した。それから再
度湿式混合、乾燥、造粒、成形して、1250℃で３
時間、300Kg／cm2の圧力でホツトプレス焼結を行
なつた。焼結体の平均結晶粒径は15μｍであり、
気孔率は0.04％であつた。同じ50モル％Fe2O3、
25モル％MnO、25モル％ZnO組成を持つ平均粒
径0.2μｍの共沈フエライト粉体と、不純物の含
有率は同じで平均粒径が0.005μｍのものと、1.5
μｍのもの３種類の共沈原料粉体から、800℃２
時間仮焼した後、同様にして1250℃で３時間、
300Kg／cm2でホツトプレスして焼結体を得た。平
均結晶粒径は10μｍで、気孔率は0.02％であつ
た。単結晶−多結晶フエライト接合体を作り、
N2中ホツトプレス熱処理により多結晶フエライ
トの単結晶化を行なつた。前述と同様の方法によ
り、単結晶化長さＬを測つたところ、α−
FeOOHを用いた場合にはＬ＝0.8mm、γ−
FeOOHを用いた場合にはＬ＝0.9mm、共沈フエラ
イトを用いた場合には平均粒径02μｍのものでＬ
＝8.5mm、平均粒径0.005μｍおよび1.5μｍのもの
でそれぞれＬ＝0.5mm、Ｌ＝0.8mmであつた。気孔
率の差を比較するため、平均粒径0.2μｍの共沈
フエライトを用いた場合のホツトプレス時の圧力
を300Kg／cm2から200Kg／cm2に下げて、気孔率を
0.04％と同じにしたもの（平均結晶粒径15μｍ）
を作り、同じ方法で単結晶化を行ない、単結晶化
長さＬを測定した。その結果、Ｌ＝６mmであり、
共沈フエライトを用いたものの方がいちじるしく
優れていることが確認された。Example 3 Final composition: 50 mol% Fe 2 O 3 , 25 mol% MnO, 25
α-FeOOH with a content of 95% is used as a raw material to become iron oxide, and γ-
Using 187.1g of each FeOOH, γ-
Using 46.3g of MnOOH, with a purity of 99.5%.
After weighing, blending and mixing ZnO40.88g, 800℃
It was calcined in the air for 2 hours. Then wet mix again, dry, granulate, mold and heat at 1250℃ for 3 hours.
Hot press sintering was carried out at a pressure of 300 kg/cm 2 for an hour. The average crystal grain size of the sintered body is 15 μm,
The porosity was 0.04%. Same 50 mol% Fe2O3 ,
Co-precipitated ferrite powder with an average particle size of 0.2 μm having a composition of 25 mol% MnO and 25 mol% ZnO, one with the same impurity content and an average particle size of 0.005 μm, and 1.5
From three types of coprecipitation raw material powders of μm, 800℃2
After calcining for 3 hours, do the same at 1250℃ for 3 hours.
A sintered body was obtained by hot pressing at 300 kg/cm 2 . The average grain size was 10 μm, and the porosity was 0.02%. Making a single crystal-polycrystal ferrite bond,
Single crystallization of polycrystalline ferrite was carried out by hot press heat treatment in N 2 . When the single crystallization length L was measured using the same method as described above, α-
When FeOOH is used, L=0.8mm, γ-
When FeOOH is used, L = 0.9 mm, and when co-precipitated ferrite is used, the average particle size is 02 μm.
= 8.5 mm, and L = 0.5 mm and L = 0.8 mm for those with average particle diameters of 0.005 μm and 1.5 μm, respectively. In order to compare the difference in porosity, when using co-precipitated ferrite with an average particle size of 0.2 μm, the pressure during hot pressing was lowered from 300Kg/cm 2 to 200Kg/cm 2 and the porosity was reduced.
Same as 0.04% (average grain size 15μm)
was prepared, single crystallized using the same method, and the single crystal length L was measured. As a result, L=6mm,
It was confirmed that the method using coprecipitated ferrite was significantly superior.
実施例 ４
立方晶スピネル構造のγ−Fe2O3と六方晶α−
Fe2O3とNiO、ZnOを用いて、50モル％Fe2O3−
25モル％NiO−25モル％ZnOの多結晶フエライト
を、実施例１と同様に秤量、混合し、800℃で２
時間、空気中において仮焼した。仮焼後再度湿式
混合し、乾燥、造粒成形後（成形圧300Kg／cm2）
1200℃で３時間、300Kg／cm2でホツトプレス焼結
を行ない、平均結晶粒径10μｍ、気孔率0.02％の
焼結体を得た。FeSO4、NiSO4、ZnSO4の水溶液
に、NaOHを加えて共沈させた50モル％Fe2O3−
25モル％NiO−25モル％ZnO組成のNi−Zn−Feフ
エライト原料粉体平均粒径0.3μｍを、出発原料
として、実施例１〜３と同様な方法で、ホツトプ
レス焼結体（平均結晶粒径８μｍ、気孔率0.01
％）を作製した。これらの多結晶フエライトを用
いて接合体を作製し、N2中ホツトプレス熱処理
を行なつた。単結晶化長さＬを測定すると、γ−
Fe2O3を用いたものではＬ＝2.5mm、α−Fe2O3を
用いたものではＬ＝0.5mm、共沈原料を用いたも
のではＬ＝７mmであつた。Example 4 γ-Fe 2 O 3 with cubic spinel structure and hexagonal α-
Using Fe 2 O 3 , NiO, ZnO, 50 mol% Fe 2 O 3 −
Polycrystalline ferrite of 25 mol% NiO-25 mol% ZnO was weighed and mixed in the same manner as in Example 1, and heated at 800°C for 2 hours.
It was calcined in air for an hour. After calcination, wet mixing again, drying, and granulation molding (molding pressure 300Kg/cm 2 )
Hot press sintering was performed at 1200° C. for 3 hours at 300 kg/cm 2 to obtain a sintered body with an average grain size of 10 μm and a porosity of 0.02%. 50 mol% Fe 2 O 3 − which was coprecipitated by adding NaOH to an aqueous solution of FeSO 4 , NiSO 4 , and ZnSO 4
A hot-pressed sintered body (average grain Diameter 8μm, porosity 0.01
%) was produced. A bonded body was prepared using these polycrystalline ferrites, and hot press heat treatment was performed in N 2 . When the single crystallization length L is measured, γ-
In the case where Fe 2 O 3 was used, L was 2.5 mm, in the case where α-Fe 2 O 3 was used, L was 0.5 mm, and in the case where a coprecipitation raw material was used, L was 7 mm.
以上、本発明に用いる共沈フエライトの粒径を
図示すると、第２図に示すようになる。横軸は共
沈原料粉の平均粒径ｄ（μｍ）、縦軸のＬはN2中
ホツトプレス熱処理による単結晶化長さＬ（mm）
を、Mn−Zn−Feフエライトについて示し、斜線
を付した領域間すなわち0.01〜1.0μｍの平均粒
径のものが単結晶化がしやすい。曲線は、代表的
な平均粒径と単結晶化長との関係を示したもので
ある。 The particle size of the coprecipitated ferrite used in the present invention is illustrated in FIG. 2. The horizontal axis is the average particle diameter d (μm) of the coprecipitated raw material powder, and the vertical axis L is the single crystallization length L (mm) by hot press heat treatment in N2 .
is shown for Mn-Zn-Fe ferrite, and single crystallization is likely to occur between the shaded areas, that is, those with an average grain size of 0.01 to 1.0 μm. The curve shows the relationship between typical average grain size and single crystallization length.
第１図Ａ，Ｂは本発明の方法による単結晶フエ
ライト化の過程を示す図、第２図は本発明の方法
において共沈原料粉の平均粒径が単結晶化に及ぼ
す影響を示す図である。
Ａ−１……種子となる単結晶フエライト、Ａ−
２……多結晶フエライト、Ａ−３……接合界面、
Ｂ−１……種子単結晶フエライト、Ｂ−２……多
結晶フエライト、Ｂ−４……単結晶体化した部
分。
Figures 1A and B are diagrams showing the process of single crystal ferrite formation by the method of the present invention, and Figure 2 is a diagram showing the influence of the average particle size of the coprecipitated raw material powder on single crystallization in the method of the present invention. be. A-1...Single crystal ferrite that becomes a seed, A-
2... Polycrystalline ferrite, A-3... Bonding interface,
B-1...Seed single-crystal ferrite, B-2...polycrystalline ferrite, B-4...single-crystalline portion.
Claims (1)
と同組成もしくはそれに近い組成で、かつ前記単
結晶フエライトと同じ結晶構造を有する多結晶フ
エライトとを接合し、この接合体を熱処理するこ
とにより、前記多結晶フエライトを前記単結晶フ
エライトと同じ結晶方位で同じ結晶構造を持つ単
結晶フエライトに育成するに際して、前記多結晶
フエライトとして湿式法で合成された共沈フエラ
イト粉体を出発原料とし、これを焼成した多結晶
を使用することを特徴とする単結晶フエライトの
製造法。 ２ 共沈フエライト粉体の粒子の平均粒径が0.01
〜1.0μｍであることを特徴とする特許請求の範
囲第１項記載の単結晶フエライトの製造法。[Claims] 1. A single crystal ferrite and a polycrystalline ferrite having the same composition or a composition similar to that of the single crystal ferrite and the same crystal structure as the single crystal ferrite are joined together, and the joined body is heat-treated. By this, when growing the polycrystalline ferrite into a single crystal ferrite having the same crystal orientation and the same crystal structure as the single crystal ferrite, a coprecipitated ferrite powder synthesized by a wet method as the polycrystalline ferrite is used as a starting material. , a method for producing single-crystal ferrite characterized by using polycrystals obtained by firing the same. 2 The average particle size of coprecipitated ferrite powder particles is 0.01
1. The method for producing a single crystal ferrite according to claim 1, wherein the crystal grain size is 1.0 μm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13273182A JPS5921591A (en) | 1982-07-28 | 1982-07-28 | Production of single crystal ferrite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13273182A JPS5921591A (en) | 1982-07-28 | 1982-07-28 | Production of single crystal ferrite |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5921591A JPS5921591A (en) | 1984-02-03 |
| JPS6215517B2 true JPS6215517B2 (en) | 1987-04-08 |
Family
ID=15088269
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13273182A Granted JPS5921591A (en) | 1982-07-28 | 1982-07-28 | Production of single crystal ferrite |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5921591A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0257918U (en) * | 1988-10-18 | 1990-04-26 |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6191091A (en) * | 1984-10-11 | 1986-05-09 | Ngk Insulators Ltd | Production of ferrite single crystal |
| JPS63230059A (en) * | 1987-03-19 | 1988-09-26 | Endouseijiyuu Tomonokai:Kk | Production of germ-free raw juice |
| JPH02231063A (en) * | 1989-03-01 | 1990-09-13 | Endouseijiyuu Tomonokai:Kk | Improvement in sterilization of production of sterilized juice |
| US8202364B2 (en) | 2002-10-11 | 2012-06-19 | Ceracomp Co., Ltd. | Method for solid-state single crystal growth |
| KR100564092B1 (en) * | 2002-10-11 | 2006-03-27 | 주식회사 세라콤 | Method for the Solid-State Single Crystal Growth |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5391053A (en) * | 1977-01-21 | 1978-08-10 | Hitachi Maxell | Ultra minute particle magnetic powder manufacturing process |
| JPS55162496A (en) * | 1979-05-31 | 1980-12-17 | Ngk Insulators Ltd | Manufacture of single crystal |
-
1982
- 1982-07-28 JP JP13273182A patent/JPS5921591A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5391053A (en) * | 1977-01-21 | 1978-08-10 | Hitachi Maxell | Ultra minute particle magnetic powder manufacturing process |
| JPS55162496A (en) * | 1979-05-31 | 1980-12-17 | Ngk Insulators Ltd | Manufacture of single crystal |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0257918U (en) * | 1988-10-18 | 1990-04-26 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5921591A (en) | 1984-02-03 |
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