KR100356363B1 - Preparation method of magnetic material having high magnetic permeability - Google Patents
Preparation method of magnetic material having high magnetic permeability Download PDFInfo
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- KR100356363B1 KR100356363B1 KR1019940035122A KR19940035122A KR100356363B1 KR 100356363 B1 KR100356363 B1 KR 100356363B1 KR 1019940035122 A KR1019940035122 A KR 1019940035122A KR 19940035122 A KR19940035122 A KR 19940035122A KR 100356363 B1 KR100356363 B1 KR 100356363B1
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- C04B35/26—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on ferrites
- C04B35/265—Compositions containing one or more ferrites of the group comprising manganese or zinc and one or more ferrites of the group comprising nickel, copper or cobalt
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- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/34—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/658—Atmosphere during thermal treatment
Abstract
Description
본 발명은 고 투자율 자성 재료의 제조 방법에 관한 것으로서, 상세하게는 자성체의 소결 공정에서 소결 분위기의 산소 분압을 조절함으로써 소결체의 밀도를 높혀 결과적으로 자성체의 투자율과 손실계수 특성을 향상시키는 방법에 관한 것이다.The present invention relates to a method of manufacturing a high permeability magnetic material, and more particularly, to a method of increasing the density of a sintered body by adjusting the oxygen partial pressure of the sintering atmosphere in the sintering process of the magnetic body and consequently improving the magnetic permeability and the loss coefficient characteristics of the magnetic body. will be.
자성 재료는 일반적으로 연질과 경질 자성재료로 크게 분류된다. 연질자성 재료는 투자율이 크고 보자력이 작은 재료이고 경질 자성 재료는 보자력이 큰 재료이다. 연질 자성 재료로서는 투자율, 자속 밀도가 크고 손실 계수가 작은 것이 바람직하다.Magnetic materials are generally classified into soft and hard magnetic materials. Soft magnetic materials are materials with high permeability and low coercivity, and hard magnetic materials are materials with high coercivity. As the soft magnetic material, one having a high magnetic permeability, a magnetic flux density and a small loss factor is preferable.
연질 자성 재료로서 대표적인 것으로서는 철-니켈의 합금, 또는 철-망간 산화물의 소성체로 대표되어지는 연질페라이트가 있다. 철-니켈 합금의 연질 자성 재료는 투자율이 매우 큰 대표적인 고 투자율 합금으로서, 통신 기기, 또는 전자 기기에 있어서, 각종 변성기, 고감도릴레이, 포화 리엑테, 자기 시일드, 자기 헤드등의 용도로 사용되어진다.Representative soft magnetic materials include soft ferrites represented by an alloy of iron-nickel or a sintered body of iron-manganese oxide. The soft magnetic material of the iron-nickel alloy is a representative high permeability alloy having a very high permeability, and is used in various kinds of transformers, high sensitivity relays, saturated reactants, magnetic shields, magnetic heads, etc. in communication devices or electronic devices. Lose.
연질 페라이트는 MFe2O4(M: 2가 금속이온 또는 그 혼합)의 분자식을 지닌 산화물이며, Mn-Zn 페라이트(M; Mn, Zn의 혼합) 및 Ni-Zn페라이트(M: Ni-Zn의 혼합)가 대표적인 것이다. 원료의 산화물 분말을 혼합한 다음 접착제를 첨가하여 E형, 항아리 모양, 막대 모양등의 목적에 따라 다양한 모양으로 압축 성형하고 1300℃ 이상의 온도로 소성하여 제조한다.Soft ferrites are oxides with a molecular formula of MFe 2 O 4 (M: divalent metal ions or mixtures thereof), Mn-Zn ferrites (M; a mixture of Mn, Zn) and Ni-Zn ferrites (M: of Ni-Zn). Mixed) is typical. After mixing the oxide powder of the raw material and then adding an adhesive, compression molding into various shapes according to the purpose of E-shaped, jar-shaped, rod-shaped, etc., it is produced by firing at a temperature of 1300 ℃ or more.
Mn-Zn 페라이트는 1MHz 정도 까지의 필터용 코일, 광대역 트랜스, 펄스트랜스의 자심으로서, 또한 자기 헤드, T.V용 편향 요오크, 플라이백트랜스등의 주요한 용도가 있다. 또한, Ni-Zn 페라이트는 100KHz 내지 100MHz 정도까지의 필터용 코일의 자심으로 사용되고 있으며, Cu-Zn 페라이트는 라디오용 안테나 코어나 중간파 트랜스의 자심으로 사용되고 있다.Mn-Zn ferrites are used as magnetic cores for filter coils, wideband transformers and pulse transformers up to about 1 MHz, and also have major uses such as magnetic heads, deflection yokes for T.V, and flyback transformers. In addition, Ni-Zn ferrite is used as a magnetic core of a coil for a filter from about 100 KHz to about 100 MHz, and Cu-Zn ferrite is used as a magnetic core of an antenna core for a radio or an intermediate wave transformer.
본 발명은 연질 페라이트들로 대표되는 고투자율 자성 재료의 제조시 투자율을 향상시키기 위한 고 투자율 자성 재료의 제조 방법에 관한 것이다.The present invention relates to a method for producing a high permeability magnetic material for improving the permeability in the manufacture of a high permeability magnetic material represented by soft ferrites.
연질 페라이트 고투자율 자성재료의 투자율 향상과 같은 자성 특성의 개선은 주로 자성체를 페라이트에 부가되는 산화니켈, 산화망간, 산화아연, 산화구리등의 조성을 변화시킴에 의하여 이루어져 왔다.Improvements in magnetic properties, such as improvement in magnetic permeability of soft ferrite high magnetic permeability magnetic materials, have been mainly made by changing the composition of nickel oxide, manganese oxide, zinc oxide, copper oxide, etc., in which magnetic material is added to ferrite.
그러나 연질 페라이트 고투자율 자성 재료의 자성 특성은 자성 재료의 조성 이외에도 자성 소결체의 결정 입경 균일성, 결정 입경의 대소, 불순물의 종류 및 함량, 응력과 같은 다른 용인에 의하여서도 크게 영향을 받는다.However, in addition to the composition of the magnetic material, the magnetic properties of the soft ferrite high permeability magnetic material are greatly influenced by other tolerances such as the uniformity of the crystal grain size of the magnetic sintered body, the size of the grain size, the type and content of impurities, and the stress.
본 발명자는 연질 페라이트의 제조시 자성 소결체의 자성특성에 미치는 상기한 여러가지 요인들에 대한 요인들중 자성체의 결정 구조 및 응력은 소성 온도, 분위기등의 소성 조건에 따라 크게 영향을 받을 수 있음에 착안하여 소성 조건에 따른 여러 가지 실험을 행한 끝에 연질 페라이트 고투자율 자성 재료의 자성 특성을 개선 할 수 있는 새로운 소성 조건을 발견하여 본 발명에 이르게 되었다.The inventors focused on the fact that the crystal structure and the stress of the magnetic body can be greatly affected by the firing conditions such as the firing temperature and the atmosphere, among the above factors for the magnetic properties of the magnetic sintered body in the manufacture of soft ferrite. After various experiments were conducted according to the firing conditions, a new firing condition was found to improve the magnetic properties of the soft ferrite high permeability magnetic material.
즉 본 발명은, 페라이트 자성 재료 분말을 접착제와 혼합하여 성형하고 소정의 온도로 소성하는 고투자율 자성 재료의 제조 방법에 있어서, 소성 공정시 대기분위기에서 700℃까지 일차로 승온하고; 700℃에서 1350℃까지의 온도 구간에서는 분당 1 내지 6℃의 온도 구배로 승온 하되 산소 분압이 1내지 10% 되도록 하고; 1350℃에서 4내지 6시간지속되는 소결 구산에서는 산소 분압을 대기의 수준인 19내지 21%로 하고; 상온으로 까지의 냉각 구산에서는 산소 분압이 150ppm이하되도록 유지되도록 하는 고투자율 자성 제료의 제조 방법을 제공한다.That is, the present invention provides a method for producing a high permeability magnetic material in which a ferrite magnetic material powder is mixed with an adhesive to be molded and calcined at a predetermined temperature, the temperature being primarily raised to 700 ° C. in an air atmosphere during the firing process; In a temperature range from 700 ° C. to 1350 ° C., the temperature is raised to a temperature gradient of 1 to 6 ° C. per minute, with an oxygen partial pressure of 1 to 10%; In the sintered Gusan, which lasted 4 to 6 hours at 1350 ° C., the oxygen partial pressure was set to 19 to 21% of the atmospheric level; Cooling to room temperature provides a method for producing a high permeability magnetic material that maintains an oxygen partial pressure of 150 ppm or less.
700℃ 에서 1350℃의 숭온 온도 구간에서 산소 분압을 1내지 10%으로 하는 본 발명에 의하여 승온 구간에서 페라이트 자성체는 산소 분압 감소에 의하여 산소 공극(Oygen vacacy: 소결체의 구조 치밀화에 주된 조절 인자로 생각되어지는 음이온 공극(anion vacancy))의 생성에 의하여 물질 이동이 보다 용이하게 진행되어 구조의 치밀화가 보다 잘 이루어져 자벽 이동(domain wall movement)및 자구회전(domain rotation)이 손십게일어나 투자율 향상이 이루어지게 된다.According to the present invention in which the oxygen partial pressure is 1 to 10% in the temperature range of 700 ° C. to 1350 ° C., the ferrite magnetic body is considered to be the main control factor in the structure of oxygen vacancy (Oygen vacacy) by decreasing the oxygen partial pressure. By the generation of anion vacancy, the mass transfer proceeds more easily, and the densification of the structure becomes better, resulting in domain wall movement and domain rotation, resulting in improved permeability. You lose.
이와 같은 본 발명의 소성 조건에 의한 소결체의 구조 치밀화에 대한 효과는 제1도 및 제2도의 결과로 보아 더욱 분명하여 진다. 제1도는 본 발명에 따라 제조 되어진 Mn-Zn계 페라이트 연자성 재료의 소결체의 미세 구조를 나타낸 전자 현미경도이며 제2도는 종래의 방법에 따라 제조되어진 동일한 조성의 Mn-Zn계 페라이트 연자성 재료의 소결체의 미세구조를 나타낸 전자 현미경도를 각각 나타낸 것으로서, 본 발명에 따른 제1도의 결과에 있어서 입자의 구성이 보다 치밀하고 입자의 크기가 균일함을 볼수 있다. 이와 같은 미세 구조의 치밀화에 따라 Mn-Zn계연자성 재료에 승온 구간에서 산소 분압을 1%으로 하는 본 발명의 방법을 적용하는 경우, 종래의 방법에 의하여 소결되어진 동일한 조성을 갖는 연질 페라이트 자성 재료에 비하여 투자율에 있어서는 25%, 손실계수에 있어서는 약 40%개선되는 효과가 있다.Such an effect on the structure densification of the sintered body by the firing conditions of the present invention becomes clearer as a result of FIGS. 1 and 2. 1 is an electron micrograph showing a fine structure of a sintered body of a Mn-Zn-based ferrite soft magnetic material manufactured according to the present invention, and FIG. 2 is a view of the Mn-Zn-based ferrite soft magnetic material having the same composition prepared according to a conventional method. As an electron micrograph showing the microstructure of the sintered body, respectively, in the results of FIG. 1 according to the present invention, it can be seen that the structure of the particles is more dense and the size of the particles is uniform. When the method of the present invention is applied to the Mn-Zn-based soft magnetic material with an oxygen partial pressure of 1% in an elevated temperature range according to the densification of such a fine structure, compared to the soft ferrite magnetic material having the same composition sintered by the conventional method. The effect is 25% on permeability and 40% on loss factor.
본 발명의 방법에 적용되어지는 자성 재료로서는 Mn-Zn 페라이트, Ni-Zn 페라이트, 또는 Cu-Zn 페라이트등의 연질 페라이트를 예로서 들 수 있다.Examples of the magnetic material to be applied to the method of the present invention include soft ferrites such as Mn-Zn ferrite, Ni-Zn ferrite, or Cu-Zn ferrite.
다음에 본 발명의 바람직한 실시예를 통하여 본 발명을 보다 상세히 설명하고자 한다. 그러나 다음의 실시예는 본 발명을 보다 쉽게 이혜하기위하여 제공되는 것일 뿐 본 발명이 다음의 실시예에 한정되는 것은 아니다.Next, the present invention will be described in more detail with reference to preferred embodiments of the present invention. However, the following examples are provided only to benefit the present invention more easily, the present invention is not limited to the following examples.
(실시예)(Example)
일산화망간 ‥‥‥‥‥ 25몰%,Manganese Monoxide ‥‥‥‥‥ 25 mol%,
산화아연 ‥‥‥‥‥ 25몰%Zinc oxide ‥‥‥‥‥ 25 mol%
산화제2철 ‥‥‥‥‥ 50몰%Ferric Oxide ‥‥‥‥‥ 50 mol%
를 통상의 방법에 따라 결합제에 혼합하여 압축 성형한 후, 소결노에서 대기의 분위기에서 700℃까지 가열 한후, 소결노의 산소 분압을 1%로 하여 1350℃까지 분당 3℃와 온도 구배로 승온한후, 소결노의 산소분압을 대기 분압으로 하고 소결노의 온도를 1350℃로 5시간 동안 유지하여 소성을 행한 후, 소결노의 산소 분압을150ppm이하로 유지하면서 온도를 상온의 수준으로 까지 냉각하여After compression molding by mixing with a binder according to a conventional method, the mixture was heated to 700 ° C. in an atmosphere of air in a sintering furnace, and then heated to a temperature gradient of 3 ° C. per minute and a temperature gradient to 1350 ° C. with an oxygen partial pressure of 1%. Thereafter, the oxygen partial pressure of the sintering furnace was set to atmospheric pressure and the temperature of the sintering furnace was kept at 1350 ° C. for 5 hours, followed by calcination, and then the temperature was cooled to room temperature while maintaining the oxygen partial pressure of the sintering furnace at 150 ppm or less.
상기의 조성을 갖는 Mn-Zn계 페라이트 연자성 소결체를 제조하였다.An Mn-Zn based ferrite soft magnetic sintered body having the above composition was prepared.
비교예Comparative example
상기한 실시예에서 승온 구간에서의 산소 분압을 대기의 산소 분압으로 한것을 제외하고는 실질적으로 실시예와 동일하게 처리하여 실시예에서와 동일한 조성을 갖는 Mn-Zn계 연자성 페라이트를 제조 하였다.In the above-described embodiment, except that the partial pressure of oxygen in the elevated temperature range was changed to the oxygen partial pressure of the atmosphere, the Mn-Zn-based soft magnetic ferrite having the same composition as in Example was manufactured.
상기 실시예와 비교예에서 제조되어진 자성 소결체를 다음의 방법에 따라 그 특성을 평가하여 그 결과를 다음의 표에 나타내었다.The magnetic sintered body manufactured in the above Examples and Comparative Examples was evaluated according to the following method, and the results are shown in the following table.
(평가 방법)(Assessment Methods)
적용 주파수 100KHz, 적용 전류 0.1mA, 권선수 20회의 조건으로 임피어던스 분석계(제작사: 미합중국 HP사, 모델명:HP4194)를 사용하여 자성체의 초기 투자율(μi)및 상대 손실 계수(tanδ/μi)를 다음의 식으로 계산하였다.The initial permeability (μi) and relative loss factor (tanδ / μi) of the magnetic material were determined using an impedance analyzer (manufacturer: HP of the United States of America, model name: HP4194) under an application frequency of 100 KHz, an application current of 0.1 mA, and 20 turns. It was calculated by the following equation.
상기의 식에서,In the above formula,
이며, 상기의 식에서 Ae: 코아 단면적(cm2), ie: 코아의 가로 방향의 길이(cm), D1 : 코아 외경(cm), D2 : 코아 내경(cm), H: 코아 두께 (cm), L : 인덕턴스(H), N : 권선수이다.In the above formula, Ae: core cross-sectional area (cm 2 ), ie: core length in the transverse direction (cm), D1: core diameter (cm), D2: core diameter (cm), H: core thickness (cm), L: Inductance (H), N: Number of turns.
<표>자성재료의 자성 특성<Table> Magnetic Properties of Magnetic Materials
제 1도는 본 발명의 방법에 따라 제조되어진 Mn-Zn계 페라이트 소결체의 미세 구조를 나타낸 현미경도이고,1 is a microscope diagram showing the fine structure of the Mn-Zn-based ferrite sintered body manufactured according to the method of the present invention,
제2도는 종래의 방법에 따라 제조되어진 Mn-Zn계 페라이트 소결체의 미세 구조를 나타낸 현미경도이다.2 is a microscopic view showing the fine structure of the Mn-Zn-based ferrite sintered body manufactured according to the conventional method.
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| KR1019940035122A KR100356363B1 (en) | 1994-12-19 | 1994-12-19 | Preparation method of magnetic material having high magnetic permeability |
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