JPH0618132B2 - Method for producing polycrystalline ferrite - Google Patents
Method for producing polycrystalline ferriteInfo
- Publication number
- JPH0618132B2 JPH0618132B2 JP62131879A JP13187987A JPH0618132B2 JP H0618132 B2 JPH0618132 B2 JP H0618132B2 JP 62131879 A JP62131879 A JP 62131879A JP 13187987 A JP13187987 A JP 13187987A JP H0618132 B2 JPH0618132 B2 JP H0618132B2
- Authority
- JP
- Japan
- Prior art keywords
- ferrite
- spinel structure
- history
- iron oxide
- polycrystalline
- 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 - Lifetime
Links
- 229910000859 α-Fe Inorganic materials 0.000 title claims description 42
- 238000004519 manufacturing process Methods 0.000 title claims description 13
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 30
- 239000000843 powder Substances 0.000 claims description 29
- 229910052596 spinel Inorganic materials 0.000 claims description 20
- 239000011029 spinel Substances 0.000 claims description 20
- 239000000203 mixture Substances 0.000 claims description 14
- 239000013078 crystal Substances 0.000 claims description 13
- 238000010304 firing Methods 0.000 claims description 13
- 239000002994 raw material Substances 0.000 claims description 11
- 230000035699 permeability Effects 0.000 claims description 7
- 238000005266 casting Methods 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 239000002253 acid Substances 0.000 claims description 3
- 239000003513 alkali Substances 0.000 claims description 3
- 238000009694 cold isostatic pressing Methods 0.000 claims description 3
- 239000002002 slurry Substances 0.000 claims description 2
- 238000000034 method Methods 0.000 description 9
- 239000002245 particle Substances 0.000 description 5
- 238000013329 compounding Methods 0.000 description 4
- 239000010802 sludge Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 238000011156 evaluation Methods 0.000 description 2
- 230000002706 hydrostatic effect Effects 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000009725 powder blending Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000001238 wet grinding Methods 0.000 description 1
Landscapes
- Magnetic Ceramics (AREA)
- Soft Magnetic Materials (AREA)
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、特に結晶粒径が15〜70μ
ｍ、気孔率が0.2％以下、初透磁率が7,000〜20,000(0.1
ＭＨz)であるＭn−Ｚn系多結晶フェライトの製造方法に
関するものである。DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to polycrystalline ferrite, especially a crystal grain size of 15 to 70 μm.
m, porosity 0.2% or less, initial permeability 7,000-20,000 (0.1
The present invention relates to a method for producing Mn-Zn-based polycrystalline ferrite which is MHz).
（従来の技術） 上述のごとき高密度多結晶フェライトの製造方法として
は、フェライト粉末をプレス成形若しくは泥漿鋳込み成
形（流込み成型）した後に真空雰囲気下で焼成する方法
が広く知られている。しかしながら多結晶体における気
孔率および気孔の大きさを十分に低減しえないために満
足すべき特性を有する製品を得るのが困難とされてい
た。(Prior Art) As a method for producing high-density polycrystalline ferrite as described above, a method is widely known in which ferrite powder is press-molded or slurry-cast (casting) and then fired in a vacuum atmosphere. However, it has been difficult to obtain a product having satisfactory properties because the porosity and the size of the pores in the polycrystalline body cannot be sufficiently reduced.
出願人は特開昭５４−１２０８９８号公報や特開昭５６
−１５５１００号公報に開示される高密度多結晶フェラ
イトの製造において、スピネル構造を有するか若しくは
スピネル構造の履歴を有する酸化鉄を原料とするフェラ
イト粉末を用い、このフェライト粉末を予備成形した
後、冷間静水圧（ＣＩＰ）を施し、真空焼成して多結晶
フェライトを製造する方法を提案している。この方法に
よれば高密度で低気孔率の多結晶フェライトの製造が可
能である。Applicants are Japanese Patent Laid-Open Nos. 54-120898 and 56
In the production of high-density polycrystalline ferrite disclosed in Japanese Patent Publication No. 155100, a ferrite powder made of iron oxide having a spinel structure or a history of spinel structure is used as a raw material, and the ferrite powder is preformed and then cooled. It proposes a method of producing polycrystalline ferrite by applying isostatic pressure (CIP) and firing in vacuum. According to this method, it is possible to manufacture a high density and low porosity polycrystalline ferrite.
その他、特開昭54-69796号公報や特開昭54-69797号公報
では、熱間静水圧（ＨＩＰ）を利用した高密度フェライ
トの製造方法が開示されているが、ＨＩＰは大がかりな
装置や多大の熱エネルギーを必要とするなど、装置的、
熱エネルギー的不利が大きい。In addition, Japanese Patent Application Laid-Open No. 54-69796 and Japanese Patent Application Laid-Open No. 54-69797 disclose a method for producing high-density ferrite using hot isostatic pressure (HIP). It requires a large amount of heat energy,
The heat energy disadvantage is large.
（発明が解決しようとする問題点） ところで、所要の磁気特性を有する製品を得るためには
多結晶体における結晶粒子径を一定の範囲内に収まるよ
うに制御することが重要である。しかるに、出願人の提
案に係る前記方法によれば、焼成温度がある特定の温度
に到達すると巨大な結晶粒子が成長する突発性異常成長
挙動を示す多結晶体が生成されやすく、結晶粒子径を焼
成温度の調整によって制御するのが必ずしも容易とは言
えない。(Problems to be Solved by the Invention) By the way, in order to obtain a product having required magnetic properties, it is important to control the crystal grain size in a polycrystalline body so as to fall within a certain range. However, according to the method of the applicant's proposal, when the firing temperature reaches a certain temperature, a polycrystalline body having a sudden abnormal growth behavior in which huge crystal grains grow is easily generated, and the crystal grain diameter is increased. It is not always easy to control by adjusting the firing temperature.
したがって本発明は、出願人の前記提案に係る方法の利
点を維持しつつ多結晶体における結晶粒径を焼成温度の
調整によって容易に制御することのできる多結晶フェラ
イトの製造方法を提供することを目的としている。Therefore, the present invention provides a method for producing a polycrystalline ferrite, which can easily control the crystal grain size in a polycrystalline body by adjusting the firing temperature while maintaining the advantages of the method proposed by the applicant. Has an aim.
（問題点を解決するための手段） この目的を達成するため、本発明は、結晶粒子径が15〜
70μｍ、気孔率が0.2％以下、初透磁率が7,000〜20,000
(0.1ＭＨz)であるＭｎ−Ｚｎ系多結晶フェライトを製造
するにあたり、スピネル構造を有するか若しくはスピネ
ル構造の履歴を有する酸化鉄粉末を原料とするフェライ
ト粉末を５〜50重量％含有し、残部がスピネル構造若し
くはその履歴を有しない酸化鉄粉末を原料とするフェラ
イト粉末からなる混合物に、酸またはアルカリを含有す
る水を加えた泥漿を、鋳込み成形により予備成形し、こ
の予備成形体を冷間静水圧により成形した後、 1,290〜
1,410 ℃の温度下で焼成することを特徴とする多結晶フ
ェライトの製造方法を要旨とするものである。(Means for Solving Problems) In order to achieve this object, the present invention has a crystal grain size of 15 to
70μm, porosity 0.2% or less, initial permeability 7,000-20,000
In producing a Mn-Zn-based polycrystalline ferrite of (0.1 MHz), 5 to 50% by weight of ferrite powder made from iron oxide powder having a spinel structure or a history of spinel structure is contained, and the balance is A mixture of water containing an acid or an alkali is added to a mixture of ferrite powder made from iron oxide powder that does not have a spinel structure or its history to preform it by casting, and this preform is allowed to cool and cool. After molding by hydraulic pressure, 1,290 ~
The gist is a method for producing a polycrystalline ferrite, which is characterized by firing at a temperature of 1,410 ° C.
（作用および限定理由） 本発明によって製造しようとするＭｎ−Ｚｎ系多結晶フ
ェライトにおいて、結晶粒子径を15〜70μｍとした理由
は、当該範囲外では所要の磁気特性、特に初透磁率が得
られないこと、並びに粒子径が70μｍを超えると脱粒が
生じやすくなり、製品として不適当であることを実験的
に確認したからである。(Operation and reason for limitation) In the Mn-Zn-based polycrystalline ferrite to be produced according to the present invention, the reason why the crystal grain size is set to 15 to 70 µm is that the required magnetic characteristics, especially the initial magnetic permeability are obtained outside the range. This is because it was experimentally confirmed that the product is not suitable and that if the particle size exceeds 70 μm, shedding is likely to occur and that it is unsuitable as a product.
また、本発明において、スピネル構造若しくはその履歴
を有する酸化鉄を原料とするフェライト粉末と、スピネ
ル構造若しくはその履歴を有しない酸化鉄を原料とする
フェライト粉末とからなる混合物を用いるにあたり、ス
ピネル構造若しくはその履歴を有する酸化鉄を原料とす
るフェライト粉末を５〜50重量％とした理由は、当該範
囲外では２種類のフェライト粉末の混合物を用いること
による効果が認められなくなることを実験的に確認した
からである。Further, in the present invention, when using a mixture of a ferrite powder made from iron oxide having a spinel structure or its history as a raw material, and a ferrite powder made from iron oxide having no spinel structure or its history, a spinel structure or It was experimentally confirmed that the reason why the ferrite powder having iron oxide having the history as the raw material was set to 5 to 50% by weight was that the effect of using the mixture of the two kinds of ferrite powder was not observed outside the range. Because.
すなわち、スピネル構造若しくはその履歴を有する酸化
鉄を原料とするフェライト粉末の配合比が５重量％未満
であると多結晶フェライトの気孔率および気孔の大きさ
を十分に低減するのが困難となる。他方、上記配合比が
50重量％を超えると多結晶体の微細な結晶粒子がある特
定の温度に到達するまでは殆ど成長せず満足すべき磁気
特性が得られず、また、ある特定の温度に達すると多結
晶体の微細な結晶粒子が巨大な結晶粒子に成長するの
で、結晶粒子径を焼成温度の調整によって制御するのが
困難となるものである。That is, if the compounding ratio of the ferrite powder made of iron oxide having a spinel structure or its history as a raw material is less than 5% by weight, it becomes difficult to sufficiently reduce the porosity and the size of the pores of the polycrystalline ferrite. On the other hand, if the above mixture ratio is
If it exceeds 50% by weight, the fine crystalline particles of the polycrystalline substance hardly grow until a certain temperature is reached and satisfactory magnetic properties cannot be obtained. Since the fine crystal particles of No. 3 grow into huge crystal particles, it becomes difficult to control the crystal particle diameter by adjusting the firing temperature.
本発明を実施するにあたり、２種類のフェライト粉末の
混合物を用いることによる効果を最も顕著に発現させる
ためには、スピネル構造若しくはその履歴を有する酸化
鉄を原料とするフェライト粉末の配合比を20〜35重量％
とするのが望ましい。In carrying out the present invention, in order to bring out the effect of using a mixture of two types of ferrite powder most remarkably, the compounding ratio of the ferrite powder made from iron oxide having a spinel structure or its history as a raw material is 20 to 35% by weight
Is desirable.
さらに本発明において、上記混合物の焼成温度を 1,290
〜1,410 ℃とした理由は、焼成温度が1,290 ℃未満であ
れば焼結が完全に行なわれず、気孔率が 0.2％を超える
ので製品として不適当となること、並びに焼成温度が
1,410℃を超えると焼結が過度に進み、結晶粒径が70μ
ｍを超えるに至り、前述したごとく脱粒が生じやすくな
り、製品として不適当となることを実験的に確認したか
らである。Furthermore, in the present invention, the firing temperature of the above mixture is 1,290
The reason for setting the temperature to 1,410 ℃ is that if the calcination temperature is less than 1,290 ℃, sintering will not be completed completely and the porosity will exceed 0.2%, making it unsuitable as a product.
If it exceeds 1,410 ℃, sintering will proceed excessively and the crystal grain size will be 70μ.
This is because it has been experimentally confirmed that, when the value exceeds m, shedding tends to occur as described above, which makes the product unsuitable.
前述した２種類のフェライト粉末の混合物を用いる本発
明において、最も好ましい特性を有する製品を実現する
上で有利な焼成温度は、 1,350〜1,380 ℃である。In the present invention using a mixture of the above-mentioned two types of ferrite powders, a firing temperature advantageous for realizing a product having the most preferable properties is 1,350 to 1,380 ° C.
なお、焼成までの各処理は、特開昭５４−１２０８９８
号公報に開示の製造工程に従って行えば良い。Each treatment up to firing is described in JP-A-54-120898.
It may be carried out according to the manufacturing process disclosed in the publication.
すなわち、前述した２種類のフェライト粉末の混合物
に、酸やアルカリを含有する水を添加してｐＨを、 1.7
〜3.5 あるいは９〜11に調整した泥漿を、鋳込み成形に
より予備成形し、この予備成形物を乾燥後、引続いて 8
00kg／cm2 以上の冷間静水圧によって成形し、しかるの
ち前述の温度条件下で焼成するのである。That is, the pH of the mixture of the above-mentioned two types of ferrite powders was adjusted to 1.7 by adding water containing acid or alkali.
~ 3.5 or 9 ~ 11 adjusted sludge is preformed by casting, and this preform is dried and then 8
It is formed by cold isostatic pressure of 00 kg / cm 2 or more, and then fired under the above-mentioned temperature conditions.
（実施例） 本発明に従い、泥漿鋳込み−冷間静水圧法によって製造
した多結晶フェライトの粒径、ＳＭＰ（初透磁率の第２
ピーク温度）、気孔率および初透磁率について調べた結
果を次表に示す。(Example) According to the present invention, the grain size of the polycrystalline ferrite produced by the slurry casting-cold hydrostatic pressure method, SMP (second of the initial permeability)
The following table shows the results obtained by examining the peak temperature), the porosity and the initial magnetic permeability.
また次表には、比較のため、従来法に従い湿式粉砕後、
乾燥解砕した粉末に５％の水を加えた調湿粉末や、 500
kg／cm2 の一軸加圧法を用いた場合の調査結果も併せて
示す。Also, in the following table, for comparison, after wet grinding according to the conventional method,
Humidified powder made by adding 5% water to dry crushed powder, 500
The results of the survey using the uniaxial pressure method of kg / cm 2 are also shown.
なお、泥漿鋳込み法を利用したときの泥漿のｐＨはいず
れも 2.5に調整し、また冷間静水圧による加圧力は1,00
0 kg/cm2とした。The pH of the sludge was adjusted to 2.5 when the sludge casting method was used, and the pressure applied by the cold hydrostatic pressure was 1,00.
It was set to 0 kg / cm 2 .
この表において配合比のＦＡおよびＦＢは、スピネル構
造若しくはその履歴を有する酸化鉄を原料とするフェラ
イト粉末と、スピネル構造若しくはその履歴を有しない
酸化鉄を原料とするフェライト粉末のそれぞれの重量％
を示すものである。本発明の実施例は、評価欄に○印お
よび◎印で示すものであり、いずれも所要の磁気特性を
有する製品を製造しうることは明らかである。特に◎印
で示した実施例は、非常に優れた特性を有する製品を容
易に製造しうる条件を規定するものである。 In this table, the compounding ratios F A and F B are the respective weights of the ferrite powder made from iron oxide having a spinel structure or its history as a raw material and the ferrite powder made from iron oxide having a spinel structure or its history as a raw material. %
Is shown. The examples of the present invention are shown by the circles and the circles in the evaluation column, and it is clear that products having the required magnetic properties can be manufactured. In particular, the examples marked with ⊚ specify the conditions under which a product having very excellent characteristics can be easily manufactured.
これに対して評価欄に×印で示した比較例は、本発明の
全ての条件を同時に満足するものではなく、得られる製
品が適当な特性を有するものでないことも明らかであ
る。On the other hand, the comparative examples indicated by X in the evaluation column do not satisfy all the conditions of the present invention at the same time, and it is clear that the obtained product does not have appropriate characteristics.
なお、実施例と、調湿粉末または／および一軸加圧を用
いた従来例とを比較すると、実施例はいずれも、従来例
の特性向上率から予測される特性値よりも気孔率および
初透磁率とも改善されており、この結果から、スピネル
型フェライト粉末の配合割合、泥漿鋳込み成形および冷
間静水圧法の組合せによる相乗効果が明瞭に認められ
る。In addition, when comparing the example with the conventional example using the humidity-conditioning powder and / or the uniaxial pressurization, in each of the examples, the porosity and the initial permeability are higher than the characteristic values predicted from the characteristic improvement rate of the conventional example. The magnetic susceptibility was also improved. From these results, the synergistic effect of the combination of the spinel type ferrite powder blending ratio, the sludge cast molding and the cold isostatic pressing method is clearly recognized.
本発明を実施して得られる高密度多結晶フェライトは、
Fe2O3 51〜53 mol％、MnO 26〜28 mol％、ZnO 19.5〜2
1.5 mol％の組成を有するものであるのが好適であり、
特にFe2O3 52.2〜53.2 mol％、MnO 26.6〜27.6 mol％、
ZnO 20.6〜20.7 mol％の組成が製品機能面から最適とい
えるものであることを確認している。The high-density polycrystalline ferrite obtained by carrying out the present invention is
Fe 2 O 3 51-53 mol%, MnO 26-28 mol%, ZnO 19.5-2
It is preferred that it has a composition of 1.5 mol%,
Especially Fe 2 O 3 52.2-53.2 mol%, MnO 26.6-27.6 mol%,
It has been confirmed that the composition of ZnO 20.6 to 20.7 mol% can be said to be optimum from the viewpoint of product functionality.
（発明の効果） 以上の記載から明らかなとおり、本発明によれば、スピ
ネル構造若しくはその履歴を有する酸化鉄を原料とする
フェライト粉末と、スピネル構造若しくはその履歴を有
しない酸化鉄を原料とするフェライト粉末とを所定の配
合比で含有する混合物を成形し、所定の温度下で焼成す
ることにより、多結晶体における結晶粒子径を焼成温度
の調整によって容易に制御することができ、磁気特性に
優れたＭｎ−Ｚｎ系高密度多結晶フェライトを製造する
ことが可能となるものである。(Effects of the Invention) As is apparent from the above description, according to the present invention, a ferrite powder using iron oxide having a spinel structure or a history thereof as a raw material and iron oxide having no spinel structure or a history thereof as a raw material are used. By molding a mixture containing ferrite powder in a predetermined compounding ratio and firing at a predetermined temperature, the crystal grain size in the polycrystalline body can be easily controlled by adjusting the firing temperature, and the magnetic characteristics can be improved. It is possible to manufacture an excellent Mn-Zn-based high-density polycrystalline ferrite.
Claims (3)
以下、初透磁率が7,000〜20,000 (0.1ＭＨz)であるＭｎ
−Ｚｎ系多結晶フェライトを製造するにあたり、 スピネル構造を有するか若しくはスピネル構造の履歴を
有する酸化鉄粉末を原料とするフェライト粉末を５〜50
重量％含有し、残部がスピネル構造若しくはその履歴を
有しない酸化鉄粉末を原料とするフェライト粉末からな
る混合物に、酸またはアルカリを含有する水を加えた泥
漿を、鋳込み成形により予備成形し、この予備成形体を
冷間静水圧により成形した後、 1,290〜1,410 ℃の温度
下で焼成することを特徴とする多結晶フェライトの製造
方法。1. A crystal grain size of 15 to 70 μm and a porosity of 0.2%.
Hereinafter, Mn having an initial magnetic permeability of 7,000 to 20,000 (0.1 MHz)
In producing a Zn-based polycrystalline ferrite, a ferrite powder having a spinel structure or a spinel structure history as an iron oxide powder is used as a raw material in an amount of 5 to 50%.
% By weight, with the balance being a mixture of ferrite powder made from iron oxide powder having no spinel structure or its history as a raw material, slurry in which water containing an acid or an alkali has been added is preformed by casting, and A method for producing polycrystalline ferrite, which comprises forming a preformed body by cold isostatic pressing and then firing it at a temperature of 1,290 to 1,410 ° C.
しくはスピネル構造の履歴を有する酸化鉄粉末を原料と
するフェライト粉末を20〜35重量％含有する特許請求の
範囲第１項記載の多結晶フェライトの製造方法。2. The polycrystalline ferrite according to claim 1, wherein the mixture contains 20 to 35% by weight of ferrite powder made of iron oxide powder having a spinel structure or a history of spinel structure. Manufacturing method.
℃である特許請求の範囲第１項または第２項記載の多結
晶フェライトの製造方法。3. The firing temperature of the molded body is 1,350 to 1,380.
The method for producing a polycrystalline ferrite according to claim 1 or 2, wherein the temperature is in ° C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62131879A JPH0618132B2 (en) | 1987-05-29 | 1987-05-29 | Method for producing polycrystalline ferrite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62131879A JPH0618132B2 (en) | 1987-05-29 | 1987-05-29 | Method for producing polycrystalline ferrite |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63299208A JPS63299208A (en) | 1988-12-06 |
| JPH0618132B2 true JPH0618132B2 (en) | 1994-03-09 |
Family
ID=15068278
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62131879A Expired - Lifetime JPH0618132B2 (en) | 1987-05-29 | 1987-05-29 | Method for producing polycrystalline ferrite |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0618132B2 (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5469796A (en) * | 1977-11-15 | 1979-06-05 | Hitachi Metals Ltd | Preparation of ferrite |
| JPS5469797A (en) * | 1977-11-15 | 1979-06-05 | Hitachi Metals Ltd | Preparation of ferrite |
| JPS61117804A (en) * | 1984-11-14 | 1986-06-05 | Sumitomo Special Metals Co Ltd | Mn-zn system soft ferrite and manufacture thereof |
-
1987
- 1987-05-29 JP JP62131879A patent/JPH0618132B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63299208A (en) | 1988-12-06 |
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