KR930008824B1 - Rhenium meterials of permanent magnet and making method thereof - Google Patents

Rhenium meterials of permanent magnet and making method thereof Download PDF

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KR930008824B1
KR930008824B1 KR1019910005466A KR910005466A KR930008824B1 KR 930008824 B1 KR930008824 B1 KR 930008824B1 KR 1019910005466 A KR1019910005466 A KR 1019910005466A KR 910005466 A KR910005466 A KR 910005466A KR 930008824 B1 KR930008824 B1 KR 930008824B1
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rare earth
permanent magnet
hours
boron
sulfur
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KR920020536A (en
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김대수
이은덕
유충식
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주식회사 럭키금속
홍종우
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • 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
    • H01F1/032—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 hard-magnetic materials
    • H01F1/04—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 hard-magnetic materials metals or alloys
    • H01F1/047—Alloys characterised by their composition
    • H01F1/053—Alloys characterised by their composition containing rare earth metals
    • H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
    • H01F1/0555—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 pressed, sintered or bonded together
    • H01F1/0557—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 pressed, sintered or bonded together sintered
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
    • H01F41/0266—Moulding; Pressing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00—Stock material or miscellaneous articles
    • Y10S428/90—Magnetic feature

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  • Chemical & Material Sciences (AREA)
  • Power Engineering (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
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Abstract

The magnet material comprises 10-40 atom % of at least one rare earth elements selected from La, Ce, Pr, Nd, Sm and Dy, 2-10 atom % boron and balance of at least one metals selected from Fe, Al, Co, Nb, Ti, Cr, Zr, Hf and V, the metals containing 0.1-5.0 atom % of at least one elements selected from S, P and C. The method for manufacturing a permanent magnet is characterized by sintering the composed powder at 1,000-1,200 deg.C for 0.5-2.0 hours and heating at 500-750 deg.C for 0.5-2.0 hours under the vacuum.

Description

희토류 영구자석 및 그 제조방법Rare earth permanent magnet and manufacturing method

제 1 도는 본 발명의 실시예 1에 따른 종래 자석과의 자기 감자 곡선(demagnetization curve).1 is a magnetic demagnetization curve with a conventional magnet according to Embodiment 1 of the present invention.

제 2 도는 본 발명의 실시예 2에 따른 종래 자석과의 자기 감자 곡선 비교도.2 is a magnetic demagnetization curve comparison with a conventional magnet according to the second embodiment of the present invention.

본 발명은 희토류(Re)-철(Fe)-붕소(B)계 영구 자석에 관한 것으로, 특히 항자력을 저하하지 않으면서 잔류 자속 밀도값을 높일 수 있음으로써 최대 에너지적을 향상시킬 수 있는 소결체 영구 자석에 관한 것이다.The present invention relates to a rare earth (Re) -iron (Fe) -boron (B) -based permanent magnet, in particular sintered permanent magnet which can improve the maximum energy by increasing the residual magnetic flux density value without lowering the coercive force It is about.

영구자석은 일반 가정의 각종 전기 제품으로부터 대형 컴퓨터의 주변 단말기까지 넓은 분야에서 사용되며 이에따라 최근에는 전기, 전자기기의 소형화, 고능률화등에 따라 컴팩트하면서도 고성능화가 요구되고 있다.Permanent magnets are used in a wide range of fields from electrical appliances of general households to peripheral terminals of large computers. Accordingly, in recent years, permanent magnets have been required to be compact and high in performance due to miniaturization and high efficiency of electricity and electronic devices.

종래의 고성능 자석은 희토류-코발트(Re-Co)자석이 주종을 이루고 그 최대 에너지적[(BH)max]이 최대 30MGOe로 되어 있으나, 사마륨(Sm)과 코발트(Co)의 원료가격이 고가이므로 더욱 값싼 영구 자석을 필요로 함은 물론 전자산업의 경, 박, 단, 소에 따라 더욱 강력한 영구자석이 필요하게 되었다. 이에 따라서 희토류 원소중 매장량이 비교적 풍부한 네오디뮴(Nd)고 가장 흔한 철(Fe)을 주성분으로 하는 Re-Fe-B계 영구자석이 일본국 특허공보소 61-34242호와 일본국 특허 공개공보소 59-64739호에 알려져 있다.Conventional high performance magnets consist of rare earth-cobalt (Re-Co) magnets and their maximum energy [(BH) max] is up to 30 MGOe, but the raw material prices of samarium (Sm) and cobalt (Co) are high. In addition to the need for cheaper permanent magnets, more powerful permanent magnets are needed, depending on the light, thin, small, and small size of the electronics industry. As a result, Neodymium (Nd), which is relatively rich in rare earth elements, and Re-Fe-B-based permanent magnets containing iron (Fe) as the most common component are Japanese Patent Laid-Open No. 61-34242 and Japanese Patent Laid-Open No. 59 Known in -64739.

그러나 Nb-Fe-B계 자체로는 항자력(bHc)이 충분하지 않아 모터용 자석으로는 사용하기에 충분하지 못하므로 알루미늄(Al), 디스프로슘(Dy), 니오븀(Nb) 등을 높게 첨가하여 사용하여 왔다. 그러나 이들 원소들을 사용함으로써 항자력은 높일 수 있으나 잔류 자속 밀도(Br)를 낮게 하므로 결과적으로 최대 에너지적[(BH)max]이 낮게 되는 문제점이 있다.However, Nb-Fe-B system itself is not enough to be used as a magnet for motor because it does not have enough coercive force (bHc). Therefore, aluminum (Al), dysprosium (Dy), niobium (Nb), etc. should be added. Has come. However, the coercive force can be increased by using these elements, but the residual magnetic flux density (Br) is lowered, resulting in a lower maximum energy [(BH) max ].

이에 본 발명은 잔류 자속 밀도값을 높이기 위하여 유황(S), 인(P), 탄소(C)를 첨가하되 항자력을 낮게 하지 않으면서 잔류 자속 밀도값을 높여서 결과적으로 최대 에너지적을 높이는데 그 목적이 있다.Therefore, the present invention adds sulfur (S), phosphorus (P), and carbon (C) to increase the residual magnetic flux density value, but increases the residual magnetic flux density value without lowering the coercive force, thereby increasing the maximum energy. have.

이하 본 발명을 상세히 설명하면 다음과 같다.Hereinafter, the present invention will be described in detail.

본 발명은 희토류 원소(La, Ce, Pr, Nd, Sm, Dy) 중에서 선택된 적어도 1종은 10∼40at%, 붕소 2∼10at%이고 나머지는 금속(Fe, Al, Co, Nb, Ti, Cr, Zr, Hf, V)중에서 선택된 적어도 1종으로 한 원자 백분비(原子 百分比)에 대하여, 여기에 유황(S), 인(P), 탄소(C)중에서 선택된 1종을 0.01∼5at% 조성시킨 소결체로 구성됨을 특징으로 한 영구자석이다.In the present invention, at least one selected from rare earth elements (La, Ce, Pr, Nd, Sm, Dy) is 10-40 at%, boron 2-10 at%, and the rest of the metals (Fe, Al, Co, Nb, Ti, Cr). Regarding the atomic percentage of at least one selected from among Z, Zr, Hf, and V), 0.01-5 at% of one selected from sulfur (S), phosphorus (P), and carbon (C) is formed. Permanent magnets, characterized in that composed of a sintered body.

본 발명에 따른 영구자석은 다음과 같이 제조된다. 희토류-금속-붕소의 조성을 갖는 합금을 진공 고주파 유도로에서 용해, 주조한 후 파쇄기를 이용하여 약 200μm 이하의 분말을 얻은 후 여기에 잔류 자속 밀도 값을 높이기 위하여 유황, 인, 탄소중에서 선택된 1종의 원소를 0.1∼5.0at% 첨가하여 습식분쇄기를 이용 평균입도가 3∼10μm인 분말로 제조한다.Permanent magnet according to the present invention is manufactured as follows. An alloy having a rare earth-metal-boron composition was melted and cast in a vacuum high frequency induction furnace to obtain a powder of about 200 μm or less using a crusher, and then selected from sulfur, phosphorus, and carbon to increase the residual magnetic flux density value. 0.1 to 5.0 at% of element is added to produce a powder having an average particle size of 3 to 10 m using a wet mill.

이렇게 얻어진 분말을 성형한 후 1,000∼1,200℃ 온도에서 0.5∼2.0시간 동안 소결하고 다시 진공중에서 500∼750℃ 온도로 0.5∼2.0시간 열처리 한다.The powder thus obtained is molded and then sintered at a temperature of 1,000 to 1,200 ° C. for 0.5 to 2.0 hours, and then heat-treated at 500 to 750 ° C. for 0.5 to 2.0 hours in a vacuum.

이와 같은 본 발명의 제조공정에서 입자의 지름이 너무 크면 항자력의 감소를 초래하고 입자지금이 너무 작으면 잔류 자속 밀도가 저하된다.In such a manufacturing process of the present invention, if the diameter of the particle is too large, the coercive force is reduced. If the particle current is too small, the residual magnetic flux density decreases.

또한, 유황, 인, 탄소중 선택된 1종의 원가 0.1at% 이하이거나 5.0at% 이상인 경우에는 잔류 자속 밀도 및/또는 항자력이 감소하여 결과적으로 최대 에너지적이 낮게 된다.In addition, when the cost of one selected from sulfur, phosphorus and carbon is 0.1 at% or less or 5.0 at% or more, the residual magnetic flux density and / or the coercive force are reduced, resulting in a lower maximum energy.

이때 상기 원소의 역할은 아직 명확히 규명되지는 않았지만 다음과 같은 이유로 판단된다. 분쇄시 상기 원소는 희토류 원소-금속-B로 된 분말에 얇은 피막을 형성하고 성형시 분말이 자기적으로 배열될때에 이 피막의 도움으로 입자의 정렬이 비교적 쉽게 되어서 잔류 자속 밀도값을 높이는 결과를 가져오게 되는 것으로 보여진다.At this time, the role of the element is not yet clearly identified, but is determined for the following reasons. When pulverized, the element forms a thin film on the rare earth element-metal-B powder, and when the powder is magnetically arranged during molding, the particles align relatively with the aid of the film, thereby increasing the residual magnetic flux density. It is shown to be imported.

이렇게 제조된 분말은 15KOe 정도의 자장중에서 0.5∼1.5ton/㎤의 압력으로 성형하고 10-3torr 이하의 진공중에서 승온하고 불활성 기체중에서 1,000∼1,200℃ 온도로 0.5∼2.0시간 동안 소결 후 10-3torr 이하의 진공중에서 500∼750℃ 온도로 0.5∼2.0시간동안 열처리를 행하여 항자력을 증가시킨다. 다음은 (표 1)과 같은 실시예를 통하여 본 발명을 설명한다.The powder thus prepared was molded at a pressure of 0.5 to 1.5 ton / cm 3 in a magnetic field of about 15 KOe, heated up in a vacuum of 10 -3 torr or less, and sintered at 1,000 to 1,200 ° C. in an inert gas for 0.5 to 2.0 hours, and then 10 -3. The coercive force is increased by performing heat treatment at a temperature of 500 to 750 캜 for 0.5 to 2.0 hours in a vacuum below torr. The following describes the present invention through the embodiment as shown in Table 1.

[실시예 1]Example 1

(표 1)과 같은 희토류 원소, 철, 붕소를 진공고주파 유도 용해로에서 용해, 주조한 후 죠크랏샤로 200μm 이하로 파쇄하고 여기에 유황을 0.1∼5.0at%, 인을 0.2at%, 탄소를 0.1at% 각각 첨가하여 볼밀로 분쇄 0.5∼10μm 입도를 갖는 분말로 하였다.Rare earth elements, iron and boron as shown in Table 1 are dissolved and cast in a vacuum high-frequency induction furnace, and then crushed to 200 μm or less with a jaw crusher, where sulfur is 0.1 to 5.0 at%, phosphorus is 0.2 at% and carbon is 0.1 at% was added and ground in a ball mill to obtain a powder having a particle size of 0.5 to 10 µm.

이를 자장중에서 0.5∼1.5ton/㎤의 압력으로 성형한 후 10-3torr 이하의 진공중에서 승온하고 알곤 기체중에서 1,050∼1,200℃ 온도로 0.5∼2.0시간 소결하였다. 이 소결체를 10-3torr 진공중에서 500∼750℃ 온도로 0.5∼2.0시간 열처리를 하였다. 그리고 자기적 특성은 진동 자력 측정장치(Vibrating sample magnetometer)로 측정하였다.This was molded at a pressure of 0.5 to 1.5 ton / cm 3 in a magnetic field, and then heated up in a vacuum of 10 −3 torr or less and sintered at an temperature of 1,050 to 1,200 ° C. in argon gas for 0.5 to 2.0 hours. This sintered compact was heat-treated for 0.5 to 2.0 hours at 500-750 degreeC in 10 -3 torr vacuum. Magnetic properties were measured by a vibrating sample magnetometer.

그 결과 자기적 특성중 항자력(bHc)에서는 본 발명(시료 1∼6)이나 종래 발명(시료 7) 공히 유사하나, 잔류자속밀도(Br)의 경우 본 발명은 최대치 12.5이고 평균 12.3 이상인데 반해 종해 발명은 12.0이고, 최대 에너지적의 경우 본 발명의 최대치는 33이고 평균 32 이상인데 반해 종래 발명은 30에 불과하였다. 제 1 도에서 곡선 A는 종래자석이고, B는 본발명(시료 2)의 영구 자석이다.As a result, the magnetic force of the magnetic force (bHc) is similar to the present invention (Samples 1 to 6) and the conventional invention (Sample 7), but the residual magnetic flux density (Br) is 12.5 at maximum and 12.3 or more on average, whereas The invention is 12.0, and the maximum energy of the present invention is 33 and the average is 32 or more, whereas the conventional invention is only 30. In Fig. 1, curve A is a conventional magnet and B is a permanent magnet of the present invention (sample 2).

[실시예 2]Example 2

(표 1)에서 시료(8∼11)와 같은 희토류 원소, 철, 붕소를 실시예 1과 같은 방법으로 파쇄하고 여기에 유황과 인을 각각 0.2at% 또는 탄소를 5.0at% 첨가하여 실시예 1과 같은 공정을 거쳐 자기적 특성을 조사한 결과 본발명(시료 8∼10)의 잔류 자속밀도, 항자력, 최대 에너지적에서 모두 종래 발명(시료 11)보다 우수 하였다. 제 2 도에서 곡선 A는 종래 자석(시료 11)이고, B는 본 발명(시료 8)이다.In Table 1, a rare earth element, iron, and boron, such as the samples (8 to 11), were crushed in the same manner as in Example 1, and sulfur and phosphorus were added thereto by adding 0.2at% of sulfur or 5.0at% of carbon, respectively. As a result of investigating the magnetic properties through the process as described above, the residual magnetic flux density, coercive force and maximum energy of the present invention (Samples 8 to 10) were superior to the conventional invention (Sample 11). In FIG. 2, curve A is a conventional magnet (sample 11), and B is the present invention (sample 8).

[실시예 3]Example 3

(표 1)의 시료(12∼15)와 같은 희토류 원소, 철, 알루미늄, 붕소를 실시예 1과 같은 방법으로 파쇄하고 여기에 유황 또는 인을 첨가하여 실시예 1과 같은 공정을 거쳐 자기적 특성을 조사한 결과 항자력은 비슷하였으나, 잔류 자속 밀도와 최대 에너지적은 본 발명이 향상되고 있음을 알 수 있었다.Rare earth elements, iron, aluminum, and boron, such as the samples 12 to 15 of Table 1, were crushed in the same manner as in Example 1, and sulfur or phosphorus was added thereto, followed by the same process as in Example 1 to obtain magnetic properties. The results showed that the coercive force was similar, but the residual magnetic flux density and the maximum energy were found to improve the present invention.

[표 1]TABLE 1

본 발명의 실시예에 따른 종래와의 비교Comparison with the prior art according to the embodiment of the present invention

Figure kpo00001
Figure kpo00001

Claims (2)

희토류 원소(La, Ce, Pr, Nd, Sm, Dy) 중에서 선택된 적어도 1종의 원소 10∼40at%, 붕소 2∼10at%이고 나머지는 금속(Fe, Al, Co, NB, Ti, Cr, Zr, Hr, V)중에서 선택된 적어도 1종으로 이루어진 원자 백분비에 대하여 여기에 유황(S), 인(P), 탄소(C) 중에서 선택된 1종의 원소를 0.01∼5.0at% 조성시킨 소결체로 구성됨을 특징으로 하는 영구자석.10 to 40 at% of at least one element selected from rare earth elements (La, Ce, Pr, Nd, Sm, Dy), 2 to 10 at% boron, and the remaining metals (Fe, Al, Co, NB, Ti, Cr, Zr) It is composed of a sintered body composed of 0.01 to 5.0 at% of one element selected from sulfur (S), phosphorus (P) and carbon (C) with respect to the atomic percentage of at least one selected from Hr and V). Characterized by permanent magnets. 희토류 원소, 붕소, 전이금속을 용해, 주조하여 잉고트를 만들고 이를 200μm 이하로 파쇄한 후 여기에 유황, 인, 탄소중에서 선택된 1종의 원소를 첨가시켜서 3∼10μm 입자가 되도록 분쇄하여, 이 분말을 성형하고 1,000∼1,200℃ 온도에서 0.5∼2시간 동안 소결시킨 후 500~750℃ 온도에서 0.5~2시간 열처리함을 특징으로 하는 영구 자석의 제조방법.Dissolve and cast rare earth elements, boron, and transition metals to make ingots, crush them to 200 μm or less, and add one element selected from sulfur, phosphorus, and carbon to pulverize them to 3 to 10 μm particles. After molding and sintering at a temperature of 1,000 to 1,200 ℃ for 0.5 to 2 hours, and a heat treatment at 500 to 750 ℃ temperature for 0.5 to 2 hours.
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