JP2009088362A - Powder magnetic core and manufacturing method thereof - Google Patents
Powder magnetic core and manufacturing method thereof Download PDFInfo
- Publication number
- JP2009088362A JP2009088362A JP2007258134A JP2007258134A JP2009088362A JP 2009088362 A JP2009088362 A JP 2009088362A JP 2007258134 A JP2007258134 A JP 2007258134A JP 2007258134 A JP2007258134 A JP 2007258134A JP 2009088362 A JP2009088362 A JP 2009088362A
- Authority
- JP
- Japan
- Prior art keywords
- dust core
- insulating film
- magnetic powder
- powder
- amount
- 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.)
- Granted
Links
- 239000000843 powder Substances 0.000 title claims abstract description 33
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 22
- 239000006247 magnetic powder Substances 0.000 claims abstract description 65
- 239000011347 resin Substances 0.000 claims abstract description 50
- 229920005989 resin Polymers 0.000 claims abstract description 50
- 239000002904 solvent Substances 0.000 claims abstract description 42
- 238000000465 moulding Methods 0.000 claims abstract description 37
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 33
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 33
- 239000010703 silicon Substances 0.000 claims abstract description 33
- 238000009835 boiling Methods 0.000 claims abstract description 26
- 239000000203 mixture Substances 0.000 claims abstract description 18
- 238000002156 mixing Methods 0.000 claims abstract description 17
- 239000000696 magnetic material Substances 0.000 claims abstract description 16
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Inorganic materials [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000001035 drying Methods 0.000 claims abstract description 10
- 229910018557 Si O Inorganic materials 0.000 claims abstract description 7
- 239000000428 dust Substances 0.000 claims description 78
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical group CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 30
- 238000000034 method Methods 0.000 abstract description 34
- 230000008569 process Effects 0.000 abstract description 9
- 238000010438 heat treatment Methods 0.000 description 26
- 239000000314 lubricant Substances 0.000 description 25
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 12
- 238000010790 dilution Methods 0.000 description 10
- 239000012895 dilution Substances 0.000 description 10
- 239000002635 aromatic organic solvent Substances 0.000 description 9
- 239000012212 insulator Substances 0.000 description 9
- 239000002245 particle Substances 0.000 description 9
- 239000007864 aqueous solution Substances 0.000 description 7
- 230000007423 decrease Effects 0.000 description 7
- 239000004094 surface-active agent Substances 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- -1 zinc stearate Chemical class 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- HGPXWXLYXNVULB-UHFFFAOYSA-M lithium stearate Chemical compound [Li+].CCCCCCCCCCCCCCCCCC([O-])=O HGPXWXLYXNVULB-UHFFFAOYSA-M 0.000 description 5
- 238000005461 lubrication Methods 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- 229910017082 Fe-Si Inorganic materials 0.000 description 4
- 229910017133 Fe—Si Inorganic materials 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000002518 antifoaming agent Substances 0.000 description 3
- 239000012298 atmosphere Substances 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 235000014113 dietary fatty acids Nutrition 0.000 description 3
- 238000007865 diluting Methods 0.000 description 3
- 239000003085 diluting agent Substances 0.000 description 3
- 229930195729 fatty acid Natural products 0.000 description 3
- 239000000194 fatty acid Substances 0.000 description 3
- 150000004665 fatty acids Chemical class 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000000550 scanning electron microscopy energy dispersive X-ray spectroscopy Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
- 238000010533 azeotropic distillation Methods 0.000 description 2
- CJZGTCYPCWQAJB-UHFFFAOYSA-L calcium stearate Chemical compound [Ca+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O CJZGTCYPCWQAJB-UHFFFAOYSA-L 0.000 description 2
- 239000008116 calcium stearate Substances 0.000 description 2
- 235000013539 calcium stearate Nutrition 0.000 description 2
- 238000003763 carbonization Methods 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- IPCSVZSSVZVIGE-UHFFFAOYSA-N hexadecanoic acid Chemical compound CCCCCCCCCCCCCCCC(O)=O IPCSVZSSVZVIGE-UHFFFAOYSA-N 0.000 description 2
- AVOVSJYQRZMDQJ-KVVVOXFISA-M lithium;(z)-octadec-9-enoate Chemical compound [Li+].CCCCCCCC\C=C/CCCCCCCC([O-])=O AVOVSJYQRZMDQJ-KVVVOXFISA-M 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 238000004080 punching Methods 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- 230000000007 visual effect Effects 0.000 description 2
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical compound [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 description 2
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 description 1
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 description 1
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 description 1
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 1
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 description 1
- 239000005642 Oleic acid Substances 0.000 description 1
- 235000021314 Palmitic acid Nutrition 0.000 description 1
- 235000021355 Stearic acid Nutrition 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 159000000009 barium salts Chemical class 0.000 description 1
- AGXUVMPSUKZYDT-UHFFFAOYSA-L barium(2+);octadecanoate Chemical compound [Ba+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O AGXUVMPSUKZYDT-UHFFFAOYSA-L 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 159000000007 calcium salts Chemical class 0.000 description 1
- HRBZRZSCMANEHQ-UHFFFAOYSA-L calcium;hexadecanoate Chemical compound [Ca+2].CCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCC([O-])=O HRBZRZSCMANEHQ-UHFFFAOYSA-L 0.000 description 1
- ZCZLQYAECBEUBH-UHFFFAOYSA-L calcium;octadec-9-enoate Chemical compound [Ca+2].CCCCCCCCC=CCCCCCCCC([O-])=O.CCCCCCCCC=CCCCCCCCC([O-])=O ZCZLQYAECBEUBH-UHFFFAOYSA-L 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000005187 foaming Methods 0.000 description 1
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 description 1
- 238000000462 isostatic pressing Methods 0.000 description 1
- 229910003002 lithium salt Inorganic materials 0.000 description 1
- 159000000002 lithium salts Chemical class 0.000 description 1
- BZMIKKVSCNHEFL-UHFFFAOYSA-M lithium;hexadecanoate Chemical compound [Li+].CCCCCCCCCCCCCCCC([O-])=O BZMIKKVSCNHEFL-UHFFFAOYSA-M 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- WQEPLUUGTLDZJY-UHFFFAOYSA-N n-Pentadecanoic acid Natural products CCCCCCCCCCCCCCC(O)=O WQEPLUUGTLDZJY-UHFFFAOYSA-N 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000002736 nonionic surfactant Substances 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 description 1
- 235000021313 oleic acid Nutrition 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 150000003751 zinc Chemical class 0.000 description 1
Images
Landscapes
- Powder Metallurgy (AREA)
- Soft Magnetic Materials (AREA)
Abstract
Description
本発明は、圧粉磁芯及びその製造方法に関し、さらに詳しくは、比抵抗が高く、かつ、圧環強度が高い圧粉磁芯及びその製造方法に関する。 The present invention relates to a dust core and a method for manufacturing the same, and more particularly to a dust core having a high specific resistance and a high crushing strength and a method for manufacturing the same.
圧粉磁芯は、軟磁性材料からなる粉末を加圧成形することにより得られるものであり、モータ、トランス、ＤＣソレノイドアクチュエータ、インバータ、スイッチング素子、ノイズフィルタ等の各種電気機器の磁芯に応用されている。 The dust core is obtained by pressure-molding a powder made of soft magnetic material and applied to the core of various electrical equipment such as motors, transformers, DC solenoid actuators, inverters, switching elements, noise filters, etc. Has been.
圧粉磁芯の高周波域での磁気的特性は、鉄損に依存し、鉄損は、主としてヒステリシス損失と渦電流損失からなる。
これらの内、ヒステリシス損失は、磁壁が結晶欠陥、介在物、内部応力等によってピンニングされることにより発生する電力損失である。従って、ヒステリシス損失を低減するためには、内部応力等を極力除く必要がある。
また、渦電流損失は、交流磁場中におかれた導体内であって磁束に対して垂直な面内に、渦電流が流れることにより発生する電力損失である。従って、渦電流損失を低減するためには、圧粉磁芯の電気比抵抗を極力大きくする必要がある。
そのため、圧粉磁芯の出発原料には、見かけの電気比抵抗を高くするために、その表面が電気絶縁性の樹脂や酸化物で被覆された軟磁性粉末を用いるのが一般的である。また、ヒステリシス損失を低減するために、成形後の圧粉磁芯に対し、残留歪みを除去するための焼鈍を行うのが一般的である。
The magnetic characteristics of the dust core in the high frequency range depend on the iron loss, and the iron loss mainly consists of hysteresis loss and eddy current loss.
Among these, the hysteresis loss is a power loss generated when the domain wall is pinned by crystal defects, inclusions, internal stress, and the like. Therefore, in order to reduce hysteresis loss, it is necessary to remove internal stress as much as possible.
Further, the eddy current loss is a power loss that is generated when an eddy current flows in a plane perpendicular to the magnetic flux in a conductor placed in an alternating magnetic field. Therefore, in order to reduce eddy current loss, it is necessary to increase the electrical specific resistance of the dust core as much as possible.
Therefore, in order to increase the apparent electrical resistivity, soft magnetic powder whose surface is coated with an electrically insulating resin or oxide is generally used as the starting material for the dust core. Moreover, in order to reduce hysteresis loss, it is common to perform annealing for removing residual strain on the dust core after molding.
圧粉磁芯は、一般に、シリコン系樹脂被膜が被覆された軟磁性粉末を加圧成形し、圧粉体を高温で熱処理し、樹脂被膜をＳｉＯx系絶縁体に変性させることにより製造されている。得られた圧粉磁芯の磁気特性や機械的特性は、一般に、軟磁性粉末の組成や形状、成形条件、熱処理条件等に依存する。そのため、圧粉磁芯に用いられる材料やその製造方法に関し、従来から種々の提案がなされている。 A dust core is generally manufactured by press-molding a soft magnetic powder coated with a silicon-based resin coating, heat-treating the green compact at a high temperature, and modifying the resin coating into a SiO x- based insulator. Yes. The magnetic properties and mechanical properties of the obtained dust core generally depend on the composition and shape of the soft magnetic powder, molding conditions, heat treatment conditions, and the like. For this reason, various proposals have conventionally been made regarding materials used for dust cores and methods for producing the same.
例えば、特許文献１には、Ｆｅを主成分とし、Ｓｉ含有量が１．５質量％以下であり、体積平均粒径が８０〜３００μｍである磁性粉末を加圧成形することにより得られ、磁性粉末の真密度（ρ0）対する圧粉磁芯の嵩密度（ρ）の比（ρ／ρ0：％）が９６％以上である圧粉磁芯が開示されている。
同文献には、このような磁性粉末を用いることによって、比較的低い周波数（１００〜２０００Ｈｚ）で使用した場合であっても、高磁気特性及び低損失を示す圧粉磁芯が得られる点が記載されている。
For example, Patent Document 1 is obtained by pressure-molding magnetic powder having Fe as a main component, Si content of 1.5% by mass or less, and volume average particle size of 80 to 300 μm, and magnetic properties. A dust core having a ratio (ρ / ρ 0 :%) of the bulk density (ρ) of the dust core to the true density (ρ 0 ) of the powder is 96% or more is disclosed.
In this document, by using such a magnetic powder, it is possible to obtain a dust core exhibiting high magnetic properties and low loss even when used at a relatively low frequency (100 to 2000 Hz). Are listed.
圧粉磁芯の損失は、磁性粉末の形状にも依存する。一般に、低損失の圧粉磁芯を得るためには、球形の磁性粉末を用いるのが好ましい。しかしながら、従来の方法をそのまま球形の磁性粉末に適用すると、粒子同士の絡み合いが起こらないために、圧粉磁芯の機械的強度が低下する。 The loss of the dust core also depends on the shape of the magnetic powder. Generally, in order to obtain a low-loss dust core, it is preferable to use a spherical magnetic powder. However, if the conventional method is applied to the spherical magnetic powder as it is, the mechanical strength of the dust core decreases because the particles are not entangled with each other.
本発明が解決しようとする課題は、機械的強度が高く、かつ電磁気特性に優れた圧粉磁芯及びその製造方法を提供することにある。
また、本発明が解決しようとする他の課題は、球形又はこれに近い形状を有する磁性粉末を使用した場合であっても、高い機械的強度及び電磁気特性が得られる圧粉磁芯及びその製造方法を提供することにある。
The problem to be solved by the present invention is to provide a dust core having high mechanical strength and excellent electromagnetic characteristics and a method for producing the same.
Further, another problem to be solved by the present invention is a dust core capable of obtaining high mechanical strength and electromagnetic characteristics even when a magnetic powder having a spherical shape or a shape close thereto is used, and its manufacture. It is to provide a method.
上記課題を解決するために本発明に係る圧粉磁芯の１番目は、
軟磁性材料からなる磁性粉末と、
前記磁性粉末を被覆する絶縁皮膜とを備え、
前記絶縁皮膜は、次の（１）式で表される組成を有することを要旨とする。
(Ｓｉ−Ｏ)100-xＣx （０＜ｘ(ａｔ％)≦２０） ・・・（１）
In order to solve the above problems, the first dust core according to the present invention is:
Magnetic powder made of soft magnetic material;
An insulating film covering the magnetic powder,
The gist is that the insulating film has a composition represented by the following formula (1).
(Si—O) 100-x C x (0 <x (at%) ≦ 20) (1)
本発明に係る圧粉磁芯の２番目は、
軟磁性材料からなる磁性粉末と、
前記磁性粉末を被覆する絶縁皮膜とを備え、
前記絶縁皮膜中の最大Ｃ量が５０ａｔ％以下であることを要旨とする。
The second of the dust core according to the present invention is:
Magnetic powder made of soft magnetic material;
An insulating film covering the magnetic powder,
The gist is that the maximum amount of C in the insulating film is 50 at% or less.
本発明に係る圧粉磁芯の３番目は、
軟磁性材料からなる磁性粉末と、
前記磁性粉末を被覆する絶縁皮膜とを備え、
前記絶縁皮膜は、次の（１）式で表される組成を有し、
前記絶縁皮膜中の最大Ｃ量が５０ａｔ％以下である圧粉磁芯。
(Ｓｉ−Ｏ)100-xＣx （０＜ｘ(ａｔ％)≦２０） ・・・（１）
The third of the dust core according to the present invention is:
Magnetic powder made of soft magnetic material;
An insulating film covering the magnetic powder,
The insulating film has a composition represented by the following formula (1):
A dust core in which the maximum amount of C in the insulating film is 50 at% or less.
(Si—O) 100-x C x (0 <x (at%) ≦ 20) (1)
さらに、本発明に係る圧粉磁芯の製造方法は、
軟磁性材料からなる磁性粉末と、シリコン系樹脂と、沸点が６０℃以下である低沸点溶媒とを混合する混合工程と、
前記混合工程で得られた混合物から溶媒を除去する乾燥工程と、
前記乾燥工程で得られた粉末を成形する成形工程と、
を備えていることを要旨とする。
Furthermore, the manufacturing method of the dust core according to the present invention includes:
A mixing step of mixing a magnetic powder made of a soft magnetic material, a silicon-based resin, and a low boiling point solvent having a boiling point of 60 ° C. or less;
A drying step for removing the solvent from the mixture obtained in the mixing step;
A molding step of molding the powder obtained in the drying step;
The main point is that
圧粉磁芯の絶縁皮膜には、耐熱性の点からシリコン系樹脂を用いるのが一般的である。シリコン系樹脂は、通常、希釈溶媒として芳香族系の有機溶媒が用いられている。そのため、シリコン系樹脂をＳｉＯy系絶縁体に変性させるために、圧粉体を高温で熱処理すると、粒界には、芳香族系の有機溶媒が炭化することにより生成するＣ相が生成する場合がある。粒界に生成したＣ相は、圧粉磁芯の強度を低下させる原因となる。
これに対し、シリコン系樹脂を低沸点溶媒で希釈し、この溶液を用いて磁性粉末の表面を樹脂で被覆すると、球形の磁性粉末を用いた場合であっても、機械的強度の高い圧粉磁芯が得られる。これは、芳香族系の有機溶媒で希釈されたシリコン系樹脂にさらに低沸点溶媒を添加すると、混合物を乾燥する際に共沸によって芳香族系の有機溶媒がほぼ完全に除去され、磁性粉末の粒界にＣ相が生成しにくくなるためと考えられる。
A silicon-based resin is generally used for the insulating film of the dust core from the viewpoint of heat resistance. In the case of a silicon resin, an aromatic organic solvent is usually used as a dilution solvent. Therefore, when the green compact is heat-treated at a high temperature in order to denature the silicon-based resin into the SiO y- based insulator, a C phase is generated at the grain boundary due to carbonization of the aromatic organic solvent. There is. The C phase generated at the grain boundary causes a reduction in the strength of the dust core.
On the other hand, when silicon resin is diluted with a low boiling point solvent and the surface of the magnetic powder is coated with the resin using this solution, even if spherical magnetic powder is used, a compact with high mechanical strength is used. A magnetic core is obtained. This is because when a low boiling point solvent is further added to a silicon resin diluted with an aromatic organic solvent, the aromatic organic solvent is almost completely removed by azeotropic distillation when the mixture is dried. This is thought to be due to the difficulty in forming the C phase at the grain boundaries.
以下、本発明の一実施の形態について詳細に説明する。
［１． 圧粉磁芯］
本発明に係る圧粉磁芯は、磁性粉末と、絶縁皮膜とを備えている。
Hereinafter, an embodiment of the present invention will be described in detail.
[1. Dust core]
The dust core according to the present invention includes a magnetic powder and an insulating film.
［１．１． 磁性粉末］
磁性粉末は、軟磁性材料からなる。本発明において、圧粉磁芯を構成する磁性粉末の組成は、特に限定されるものではなく、種々の軟磁性材料を用いることができる。特に、Ｆｅを主成分とする軟磁性材料は、高い磁気特性を有しているので、磁性粉末として好適である。ここで、「Ｆｅを主成分とする軟磁性材料」とは、Ｆｅの含有量が９０ｗｔ％以上である金属材料をいう。
[1.1. Magnetic powder]
The magnetic powder is made of a soft magnetic material. In the present invention, the composition of the magnetic powder constituting the dust core is not particularly limited, and various soft magnetic materials can be used. In particular, a soft magnetic material mainly composed of Fe is suitable as a magnetic powder because it has high magnetic properties. Here, the “soft magnetic material containing Fe as a main component” refers to a metal material having an Fe content of 90 wt% or more.
本発明において使用可能な軟磁性材料としては、具体的には、
（１）純鉄、
（２）０．５〜３．５ｗｔ％のＳｉを含むＦｅ−Ｓｉ合金、
（３）１．０〜３．０ｗｔ％のＡｌを含むＦｅ−Ａｌ合金、
（４）Ｆｅ−Ｎｉ合金、
などがある。
これらの中でも、Ｆｅ−Ｓｉ合金は、相対的に低コストであり、かつ、高い磁気特性を有しているので、磁性粉末として特に好適である。
As a soft magnetic material that can be used in the present invention, specifically,
(1) Pure iron,
(2) Fe—Si alloy containing 0.5 to 3.5 wt% of Si,
(3) Fe-Al alloy containing 1.0 to 3.0 wt% Al,
(4) Fe-Ni alloy,
and so on.
Among these, Fe—Si alloys are particularly suitable as magnetic powder because they are relatively low cost and have high magnetic properties.
磁性粉末の平均粒径は、特に限定されるものではなく、目的に応じて任意に選択することができる。一般に、磁性粉末の粒径が小さくなるほど、渦電流が流れる領域が狭くなるので、渦電流損失を小さくすることができる。一方、粒径が大きくなるほど、磁壁移動が容易化し、ヒステリシス損失を小さくすることができる。鉄損の少ない圧粉磁芯を得るためには、磁性粉末の平均粒径は、５μｍ以上５００μｍ以下が好ましく、さらに好ましくは、２０μｍ以上２００μｍ以下である。
磁性粉末の形状も、特に限定されるものではなく、ガスアトマイズ粉のような球状粉、水アトマイズ粉のような不定形粉末、あるいは、これらの中間の形状を有するガス水アトマイズ粉のいずれであっても良い。一般に、磁性粉末の形状が球形に近づくほど、圧粉磁芯の損失は小さくなるが、機械的強度は低下する傾向にある。しかしながら、後述する本発明に係る方法を用いると、球形又はこれに近い形状を有する磁性粉末を用いた場合であっても、機械的強度の高い圧粉磁芯が得られる。
The average particle diameter of the magnetic powder is not particularly limited and can be arbitrarily selected according to the purpose. In general, the smaller the particle size of the magnetic powder, the narrower the region through which eddy current flows, so that eddy current loss can be reduced. On the other hand, the larger the particle size, the easier the domain wall movement and the hysteresis loss can be reduced. In order to obtain a dust core with low iron loss, the average particle size of the magnetic powder is preferably 5 μm or more and 500 μm or less, and more preferably 20 μm or more and 200 μm or less.
The shape of the magnetic powder is not particularly limited, either spherical powder such as gas atomized powder, amorphous powder such as water atomized powder, or gas water atomized powder having an intermediate shape between them. Also good. Generally, the closer the magnetic powder shape is to a spherical shape, the smaller the loss of the dust core, but the lower the mechanical strength. However, when the method according to the present invention described later is used, a powder magnetic core having high mechanical strength can be obtained even when a magnetic powder having a spherical shape or a shape close thereto is used.
［１．２． 絶縁皮膜］
絶縁皮膜は、磁性粉末の周囲を被覆し、圧粉磁芯の見かけの電気比抵抗を高くするためのものである。本発明において絶縁皮膜は、後述するように、磁性粉末の周囲をシリコン系樹脂で被覆し、圧粉成形後に熱処理することにより得られる。そのため、絶縁皮膜は、ＳｉＯy系絶縁体を主成分とする。絶縁皮膜中のＯ／Ｓｉ比（ｙの値）は、理想的には２であるが、製造条件によってはＯ／Ｓｉ比が２よりずれる場合もある。
[1.2. Insulating film]
The insulating film covers the periphery of the magnetic powder to increase the apparent electrical resistivity of the dust core. In the present invention, as will be described later, the insulating film is obtained by coating the periphery of a magnetic powder with a silicon-based resin and performing a heat treatment after compacting. Therefore, the insulating film contains a SiO y insulator as a main component. The O / Si ratio (value of y) in the insulating film is ideally 2 but the O / Si ratio may deviate from 2 depending on the manufacturing conditions.
本発明において、絶縁皮膜は、さらに以下の（ａ）又は（ｂ）のいずれか１以上の条件を備えていることを特徴とする。この場合、絶縁皮膜は、下記のいずれか一方の条件を満たしていても良く、あるいは、双方の条件を同時に満たしていても良い。 In the present invention, the insulating film is further characterized by having one or more of the following conditions (a) or (b). In this case, the insulating film may satisfy one of the following conditions, or may satisfy both conditions simultaneously.
（ａ） 絶縁皮膜は、次の（１）式で表される組成を有する。
(Ｓｉ−Ｏ)100-xＣx （０＜ｘ(ａｔ％)≦２０） ・・・（１）
（１）式中、「（Ｓｉ−Ｏ）」は、絶縁皮膜の主成分がＳｉＯy系絶縁体であることを表す。また、「ｘ」は、ＳｉＯy系絶縁体に含まれるＣ量（ａｔ％）を表す。
絶縁皮膜中に含まれるＣ量がある一定量を超えると、絶縁皮膜中にＣ相（Ｃ量が７０ａｔ％以上の領域）が生成しやすくなる。絶縁皮膜中に生成したＣ相は、圧粉磁芯の強度を低下させる原因となる。Ｃ相の生成を抑制するためには、絶縁皮膜中のＣ量は、２０ａｔ％以下が好ましい。絶縁皮膜中のＣ量は、さらに好ましくは１０ａｔ％以下、さらに好ましくは５ａｔ％以下である。
なお、「絶縁皮膜中のＣ量」とは、同一試料中から無作為に選んだ４点以上の領域について測定されたＣ量の平均値をいう。微少領域のＣ量の測定方法は、特に限定されるものではなく、ＳＥＭ／ＥＤＸ等の各種の装置を用いて測定することができる。
(A) The insulating film has a composition represented by the following formula (1).
(Si—O) 100-x C x (0 <x (at%) ≦ 20) (1)
In the formula (1), “(Si—O)” represents that the main component of the insulating film is a SiO y -based insulator. “X” represents the amount of C (at%) contained in the SiO y -based insulator.
When the amount of C contained in the insulating film exceeds a certain amount, a C phase (a region where the C amount is 70 at% or more) is easily generated in the insulating film. The C phase generated in the insulating film causes a reduction in the strength of the dust core. In order to suppress the generation of the C phase, the amount of C in the insulating film is preferably 20 at% or less. The amount of C in the insulating film is more preferably 10 at% or less, and further preferably 5 at% or less.
Note that “the amount of C in the insulating film” refers to an average value of the amounts of C measured for four or more regions randomly selected from the same sample. The method for measuring the amount of C in the minute region is not particularly limited, and can be measured using various devices such as SEM / EDX.
（ｂ） 絶縁皮膜は、最大Ｃ量が５０ａｔ％以下である。
ここで、「最大Ｃ量」とは、同一試料中から選んだ４点以上の高Ｃ領域について測定されたＣ量の最大値をいう。微少領域のＣ量の測定方法は、特に限定されるものではなく、ＳＥＭ／ＥＤＸ等の各種の装置を用いて測定することができる。
製造条件が不適切な圧粉磁芯をＳＥＭ等で観察すると、絶縁皮膜中に、絶縁皮膜とほぼ同等の厚さを有する暗色の領域（Ｃ相）を確認することができる。この場合、「高Ｃ領域」とは、このような暗色の領域をいう。
一方、後述する方法を用いると、実質的にＣ相のない絶縁皮膜が得られる。この場合、「高Ｃ領域」とは、同一試料中から無作為に選んだ領域をいい、最大Ｃ量は、絶縁皮膜中のＣ量と同義となる。
最大Ｃ量が５０ａｔ％を超えると、絶縁皮膜にＣ相が生成しやすくなる。絶縁皮膜中に生成したＣ相は、圧粉磁芯の強度を低下させる原因となる。Ｃ相の生成を抑制するためには、最大Ｃ量は、５０ａｔ％以下が好ましい。最大Ｃ量は、さらに好ましくは２０ａｔ％以下、さらに好ましくは１０ａｔ％以下、さらに好ましくは５ａｔ％以下である。
(B) The insulating film has a maximum C amount of 50 at% or less.
Here, the “maximum C amount” refers to the maximum value of the C amount measured for four or more high C regions selected from the same sample. The method for measuring the amount of C in the minute region is not particularly limited, and can be measured using various devices such as SEM / EDX.
When a dust core with inappropriate manufacturing conditions is observed with an SEM or the like, a dark region (phase C) having a thickness substantially equal to that of the insulating film can be confirmed in the insulating film. In this case, the “high C region” refers to such a dark region.
On the other hand, when the method described later is used, an insulating film substantially free of C phase can be obtained. In this case, the “high C region” refers to a region randomly selected from the same sample, and the maximum C amount is synonymous with the C amount in the insulating film.
When the maximum C amount exceeds 50 at%, a C phase is likely to be generated in the insulating film. The C phase generated in the insulating film causes a reduction in the strength of the dust core. In order to suppress the generation of C phase, the maximum C amount is preferably 50 at% or less. The maximum C amount is more preferably 20 at% or less, further preferably 10 at% or less, and further preferably 5 at% or less.
圧粉磁芯に含まれる絶縁皮膜の含有量は、圧粉磁芯の電磁気特性及び機械的特性に影響を与える。一般に、絶縁皮膜の含有量が多くなるほど、電気比抵抗及び圧環強度が高くなる。電磁気特性及び機械的特性に優れた圧粉磁芯を得るためには、絶縁皮膜の含有量は、磁性粉末に対するシリコン系樹脂の添加量に換算して０．２ｗｔ％以上が好ましい。
一方、絶縁皮膜の含有量が過剰になると、圧粉磁芯全体に占める非磁性材料の割合が多くなり、磁束密度の低下を招く。従って、絶縁皮膜の含有量は、磁性粉末に対するシリコン系樹脂の添加量に換算して１．０ｗｔ％以下が好ましい。
The content of the insulating film contained in the dust core affects the electromagnetic properties and mechanical properties of the dust core. In general, the greater the content of the insulating film, the higher the electrical resistivity and the crushing strength. In order to obtain a dust core excellent in electromagnetic characteristics and mechanical characteristics, the content of the insulating film is preferably 0.2 wt% or more in terms of the amount of silicon resin added to the magnetic powder.
On the other hand, when the content of the insulating film is excessive, the proportion of the nonmagnetic material in the entire dust core increases and the magnetic flux density is reduced. Therefore, the content of the insulating film is preferably 1.0 wt% or less in terms of the amount of silicon resin added to the magnetic powder.
［２． 圧粉磁芯の製造方法］
本発明に係る圧粉磁芯の製造方法は、混合工程と、乾燥工程と、成形工程とを備えている。本発明に係る圧粉磁芯の製造方法は、さらに、熱処理工程を備えていても良い。
[2. Manufacturing method of dust core]
The method for manufacturing a dust core according to the present invention includes a mixing step, a drying step, and a forming step. The method for manufacturing a dust core according to the present invention may further include a heat treatment step.
［２．１． 混合工程］
混合工程は、軟磁性材料からなる磁性粉末と、シリコン系樹脂と、沸点が６０℃以下である低沸点溶媒とを混合する工程である。
シリコン系樹脂の種類は、特に限定されるものではなく、高温での熱処理によりＳｉＯy系絶縁体に変性させることが可能なものであればよい。磁性粉末に対するシリコン系樹脂との添加量は、上述したように、０．２〜１．０ｗｔ％が好ましい。
[2.1. Mixing process]
The mixing step is a step of mixing a magnetic powder made of a soft magnetic material, a silicon resin, and a low boiling point solvent having a boiling point of 60 ° C. or lower.
The type of silicon resin is not particularly limited as long as it can be modified into a SiO y insulator by heat treatment at a high temperature. As described above, the amount of silicon resin added to the magnetic powder is preferably 0.2 to 1.0 wt%.
市販のシリコン系樹脂は、通常、芳香族系の有機溶媒により希釈されている。本発明においては、このシリコン系樹脂溶液にさらに低沸点溶媒を加えて希釈する。この点が従来の方法とは異なる。ここで、「低沸点溶媒」とは、沸点が６０℃以下である有機溶媒をいう。低沸点溶媒としては、具体的には、アセトンなどがある。 Commercially available silicon resins are usually diluted with aromatic organic solvents. In the present invention, the silicon resin solution is further diluted by adding a low boiling point solvent. This is different from the conventional method. Here, the “low boiling point solvent” refers to an organic solvent having a boiling point of 60 ° C. or lower. Specific examples of the low boiling point solvent include acetone.
低沸点溶媒の混合比は、圧粉磁芯の機械的特性に影響を与える。一般に、シリコン系樹脂の重量（Ｗ（ｇ））に対する低沸点溶媒の添加量（Ｖ（ｃｃ））の比（Ｖ／Ｗ（ｃｃ／ｇ））が少なすぎると、機械的特性が低下する。これは、低沸点溶媒の量が少なくなるほど、絶縁皮膜中にＣ相が生成しやすくなるためと考えられる。高強度の圧粉磁芯を得るためには、Ｖ／Ｗ比は、１０ｃｃ／ｇ以上が好ましい。
一方、Ｖ／Ｗ比が大きくなりすぎると、かえって機械的特性が低下する。これは、Ｖ／Ｗ比が大きくなりすぎると、樹脂と磁性粉末との接触確率が低下し、磁性粉末の表面が樹脂で均一に被覆されにくくなるためと考えられる。従って、Ｖ／Ｗ比は、４０ｃｃ／ｇ以下が好ましい。Ｖ／Ｗ比は、さらに好ましくは３５ｃｃ／ｇ以下、さらに好ましくは３０ｃｃ／ｇ以下である。
The mixing ratio of the low boiling point solvent affects the mechanical properties of the dust core. Generally, when the ratio (V / W (cc / g)) of the addition amount (V (cc)) of the low boiling point solvent to the weight (W (g)) of the silicon-based resin is too small, the mechanical characteristics are deteriorated. This is considered because the C phase is more easily generated in the insulating film as the amount of the low boiling point solvent decreases. In order to obtain a high-strength dust core, the V / W ratio is preferably 10 cc / g or more.
On the other hand, if the V / W ratio is too large, the mechanical properties are rather deteriorated. This is presumably because if the V / W ratio becomes too large, the contact probability between the resin and the magnetic powder decreases, and the surface of the magnetic powder is difficult to be uniformly coated with the resin. Therefore, the V / W ratio is preferably 40 cc / g or less. The V / W ratio is more preferably 35 cc / g or less, and further preferably 30 cc / g or less.
［２．２． 乾燥工程］
乾燥工程は、混合工程で得られた混合物から溶媒を除去する工程である。
溶媒の除去は、具体的には、混合物を所定の温度に加熱することにより行う。加熱温度は、特に限定されるものではなく、使用する樹脂や溶媒の種類、配合比等に応じて最適な温度を選択する。一般に、加熱温度が高すぎると、圧粉磁芯の電磁気特性や機械的特性が低下する傾向がある。これは、加熱温度が高すぎると、溶媒が沸騰し、磁性粉末の表面が樹脂で均一に被覆されなくなるためと考えられる。従って、加熱温度は、低沸点溶媒の沸点以下が好ましい。
溶媒が完全に揮発した後、固形分を解砕し、適当な粒度に揃える。
[2.2. Drying process]
A drying process is a process of removing a solvent from the mixture obtained at the mixing process.
Specifically, the solvent is removed by heating the mixture to a predetermined temperature. The heating temperature is not particularly limited, and an optimum temperature is selected according to the type of resin and solvent to be used, the mixing ratio, and the like. In general, if the heating temperature is too high, the electromagnetic properties and mechanical properties of the dust core tend to deteriorate. This is presumably because if the heating temperature is too high, the solvent will boil and the surface of the magnetic powder will not be uniformly coated with the resin. Therefore, the heating temperature is preferably not higher than the boiling point of the low boiling point solvent.
After the solvent is completely volatilized, the solid content is crushed to obtain an appropriate particle size.
［２．３． 成形工程］
成形工程は、乾燥工程で得られた粉末を所定の形状に成形する工程である。
粉末の成形方法には、一軸加圧成形法、静水圧成形法等、種々の方法があるが、本発明においては、いずれの成形方法を用いても良い。
また、粉末を成形する際には、一般に、粉末−粉末間及び／又は粉末−金型間の摩擦を低減するために、潤滑剤が使用される。この潤滑剤は、粉末に混合（内部添加法）しても良く、あるいは、金型表面に塗布（外部添加法）しても良い。
さらに、成形温度、成形圧力等の成形条件は、粉末の材質、成形体の用途、要求特性等に応じて、最適な条件を選択する。
[2.3. Molding process]
The forming step is a step of forming the powder obtained in the drying step into a predetermined shape.
There are various powder molding methods such as a uniaxial pressure molding method and an isostatic pressing method, and any molding method may be used in the present invention.
Further, when forming a powder, a lubricant is generally used to reduce friction between the powder and the powder and / or between the powder and the mold. This lubricant may be mixed with the powder (internal addition method) or applied to the mold surface (external addition method).
Further, as the molding conditions such as molding temperature and molding pressure, optimum conditions are selected according to the material of the powder, the use of the molded body, the required characteristics, and the like.
これらの成形方法の中でも、金型潤滑温間高圧成形法は、高密度の圧粉体を製造する方法として特に好適である。ここで、「金型潤滑温間高圧成形法」とは、粉末に潤滑剤を添加することなく、金型内面に潤滑剤を塗布し、所定の温度（温間）において、所定の圧力（高圧）で一軸加圧成形する方法である。 Among these molding methods, the die lubrication warm high pressure molding method is particularly suitable as a method for producing a high-density green compact. Here, “the mold lubrication warm high pressure molding method” means that a lubricant is applied to the inner surface of the mold without adding a lubricant to the powder, and a predetermined pressure (high pressure) is applied at a predetermined temperature (warm). ) By uniaxial pressure molding.
金型潤滑温間高圧成形法に用いられる潤滑剤としては、高級脂肪酸系潤滑剤、及び、その金属塩が好適である。高級脂肪酸としては、具体的には、ステアリン酸、パルチミン酸、オレイン酸等がある。
また、高級脂肪酸の金属塩としては、具体的には、
（１）ステアリン酸リチウム、パルチミン酸リチウム、オレイン酸リチウム等のリチウム塩、
（２）ステアリン酸カルシウム、パルチミン酸カルシウム、オレイン酸カルシウム等のカルシウム塩、
（３）ステアリン酸亜鉛等の亜鉛塩、
（４）ステアリン酸バリウム等のバリウム塩、
等がある。
これらの中でも、ステアリン酸リチウム、ステアリン酸カルシウム、及び、ステアリン酸亜鉛は、金型潤滑温間高圧成形法用の潤滑剤として特に好適である。
As the lubricant used in the mold lubrication warm high pressure molding method, a higher fatty acid-based lubricant and a metal salt thereof are suitable. Specific examples of higher fatty acids include stearic acid, palmitic acid, and oleic acid.
Moreover, as a metal salt of higher fatty acid, specifically,
(1) lithium salts such as lithium stearate, lithium palmitate, lithium oleate,
(2) calcium salts such as calcium stearate, calcium palmitate, calcium oleate,
(3) Zinc salts such as zinc stearate,
(4) barium salts such as barium stearate,
Etc.
Among these, lithium stearate, calcium stearate, and zinc stearate are particularly suitable as lubricants for mold lubrication warm high pressure molding methods.
潤滑剤の金型への塗布は、スプレーガン、静電ガン等を用いて、潤滑剤を分散させた水溶液を加熱された金型内面に噴霧することにより行う。
水溶液中の潤滑剤の量は、０．１ｗｔ％以上５ｗｔ％以下が好ましい。潤滑剤の量が０．１ｗｔ％未満であると、十分な潤滑効果が得られない。一方、潤滑剤の量が５ｗｔ％を超えると、圧粉体表面に過剰の潤滑剤が残留するので好ましくない。潤滑剤の量は、さらに好ましくは、０．５ｗｔ％以上２ｗｔ％以下である。
The lubricant is applied to the mold by spraying an aqueous solution in which the lubricant is dispersed onto the heated inner surface of the mold using a spray gun, an electrostatic gun or the like.
The amount of the lubricant in the aqueous solution is preferably 0.1 wt% or more and 5 wt% or less. If the amount of the lubricant is less than 0.1 wt%, a sufficient lubricating effect cannot be obtained. On the other hand, if the amount of the lubricant exceeds 5 wt%, an excessive lubricant remains on the green compact surface, which is not preferable. The amount of the lubricant is more preferably 0.5 wt% or more and 2 wt% or less.
また、潤滑剤を分散させた水溶液には、界面活性剤を添加しても良い。界面活性剤を添加すると、潤滑剤をより均一に分散させることができる。界面活性剤としては、具体的には、アルキルフェノール系の界面活性剤、ポリオキシエチレンノニルフェニルエーテル（ＥＯ）６、ポリオキシエチレンノニルフェニルエーテル（ＥＯ）１０、アニオン性非イオン型界面活性剤、ホウ酸エステル系エマルボンＴ−８０等がある。これらは、２種以上を組み合わせて用いても良い。
例えば、潤滑剤としてステアリン酸リチウムを用いる場合、界面活性剤としてポリオキシエチレンノニルフェニルエーテル（ＥＯ）６、ポリオキシエチレンノニルフェニルエーテル（ＥＯ）１０、及び、ホウ酸エステル系エマルボンＴ−８０の３種類を同時に添加すると、単独で添加した場合に比べて、分散性が向上する。
水溶液中に界面活性剤を添加する場合、噴霧に適した粘度の水溶液を得るためには、界面活性剤の量は、１．５ｖｏｌ％以上１５ｖｏｌ％が好ましい。
A surfactant may be added to the aqueous solution in which the lubricant is dispersed. When a surfactant is added, the lubricant can be more uniformly dispersed. Specific examples of surfactants include alkylphenol surfactants, polyoxyethylene nonylphenyl ether (EO) 6, polyoxyethylene nonyl phenyl ether (EO) 10, anionic nonionic surfactants, boron Examples include acid ester-based Emalbon T-80. You may use these in combination of 2 or more type.
For example, when lithium stearate is used as a lubricant, polyoxyethylene nonylphenyl ether (EO) 6, polyoxyethylene nonylphenyl ether (EO) 10, and borate ester type Emalbon T-80 3 are used as the surfactant. When the types are added simultaneously, the dispersibility is improved as compared with the case where the types are added alone.
When a surfactant is added to the aqueous solution, the amount of the surfactant is preferably 1.5 vol% or more and 15 vol% in order to obtain an aqueous solution having a viscosity suitable for spraying.
また、潤滑剤溶液に対し、さらに消泡剤（例えば、シリコン系の消泡剤等）を添加しても良い。水溶液の泡立ちが激しいと、金型内面への均一な被膜形成が困難となる。水溶液中の消泡剤の量は、０．１ｖｏｌ％以上１ｖｏｌ％以下が好ましい。 Further, an antifoaming agent (for example, a silicon-based antifoaming agent) may be added to the lubricant solution. When the foaming of the aqueous solution is intense, it becomes difficult to form a uniform film on the inner surface of the mold. The amount of the antifoaming agent in the aqueous solution is preferably 0.1 vol% or more and 1 vol% or less.
金型の加熱温度は、潤滑剤溶液を金型内面に噴霧した時に、水分が素早く蒸発して、金型内面に潤滑剤被膜を均一に形成することができる温度であれば良い。但し、金型の温度が高くなりすぎると、潤滑剤が溶融し、均一な被膜が得られない。従って、金型の加熱温度は、潤滑剤の融点（例えば、ステアリン酸リチウムの場合は、２２０℃）未満の温度とするのが好ましい。金型の加熱温度は、具体的には、１００℃以上２００℃以下が好ましく、さらに好ましくは、１２０℃以上１８０℃以下である。 The heating temperature of the mold may be a temperature at which when the lubricant solution is sprayed on the inner surface of the mold, moisture can be quickly evaporated and a lubricant film can be uniformly formed on the inner surface of the mold. However, if the temperature of the mold becomes too high, the lubricant melts and a uniform film cannot be obtained. Accordingly, the heating temperature of the mold is preferably set to a temperature lower than the melting point of the lubricant (for example, 220 ° C. in the case of lithium stearate). Specifically, the heating temperature of the mold is preferably 100 ° C. or higher and 200 ° C. or lower, and more preferably 120 ° C. or higher and 180 ° C. or lower.
金型内面に潤滑剤被膜を形成した後、加熱された金型内に粉末を充填し、所定の圧力で成形する。一般に、成形時の圧力が高くなるほど高密度の圧粉体が得られるが、圧力が高くなりすぎると、金型内面と圧粉体との間でかじりが発生したり、あるいは、抜き圧が増大する。しかしながら、金型内面に潤滑剤被膜を形成し、温間で成形を行うと、成形圧力を増大させても、かじりの発生や抜き圧の増大を抑制することができる。
高密度の圧粉体を得るためには、成形圧力は、６００ＭＰａ以上が好ましく、さらに好ましくは、７００ＭＰａ以上、さらに好ましくは、１０００ＭＰａ以上である。但し、成形圧力が高くなり過ぎると、金型寿命が低下する。従って、成形圧力は、２０００ＭＰａ以下が好ましく、さらに好ましくは、１５００ＭＰａ以下である。
After forming the lubricant film on the inner surface of the mold, the heated mold is filled with powder and molded at a predetermined pressure. In general, the higher the pressure during molding, the higher the density green compact will be obtained. However, if the pressure becomes too high, galling will occur between the mold inner surface and the green compact, or the punching pressure will increase. To do. However, when a lubricant film is formed on the inner surface of the mold and molding is performed warm, even if the molding pressure is increased, the occurrence of galling and the increase in the punching pressure can be suppressed.
In order to obtain a high-density green compact, the molding pressure is preferably 600 MPa or more, more preferably 700 MPa or more, and still more preferably 1000 MPa or more. However, if the molding pressure becomes too high, the mold life will be reduced. Accordingly, the molding pressure is preferably 2000 MPa or less, and more preferably 1500 MPa or less.
［２．４． 熱処理工程］
成形工程で得られた圧粉磁芯は、そのまま使用することもできるが、通常は、残留歪みを除去するための熱処理を行う。圧粉磁芯に成形時の残留歪みが残っていると、保持力の増加、透磁率の減少、ヒステリシス損失の増加などの磁気特性の低下を招く。また、絶縁皮膜としてシリコン系樹脂を用いる場合において、見かけの電気比抵抗を増大させるためには、シリコン系樹脂をＳｉＯy系絶縁体に変性させることが好ましい。従って、磁気特性に優れた圧粉磁芯を得るためには、残留歪みを除去し、かつシリコン系樹脂をＳｉＯy系絶縁体に変性させるための焼鈍を行うのが好ましい。
[2.4. Heat treatment process]
The dust core obtained in the molding process can be used as it is, but usually heat treatment is performed to remove residual strain. If the residual strain at the time of molding remains in the dust core, magnetic properties such as an increase in coercive force, a decrease in magnetic permeability, and an increase in hysteresis loss are caused. Further, in the case of using a silicon-based resin as the insulating film, it is preferable to modify the silicon-based resin into a SiO y- based insulator in order to increase the apparent electrical specific resistance. Therefore, in order to obtain a dust core having excellent magnetic properties, it is preferable to perform annealing for removing residual strain and modifying the silicon-based resin into a SiO y -based insulator.
熱処理は、不活性雰囲気下（例えば、アルゴン中、真空中など）で行う。熱処理を酸化雰囲気下で行うと、磁性粉末が酸化し、磁気特性が低下するので好ましくない。
熱処理温度は、圧粉体中の残留歪みが十分に除去されるように、磁性粉末の組成、成形条件等に応じて最適な温度を選択する。同様に、熱処理時間は、圧粉体中の残留歪みが十分に除去されるように、磁性粉末の組成、熱処理温度等に応じて最適な温度を選択する。一般に、熱処理温度が低すぎる場合及び／又は熱処理時間が短すぎる場合、残留歪みの除去が不十分となる。一方、熱処理温度が高すぎる場合及び／又は熱処理時間が長すぎる場合、成分元素の拡散等によって圧粉体の磁気特性が低下する。
例えば、Ｆｅ−Ｓｉ合金とシリコン系樹脂からなる圧粉体の場合、熱処理温度は、６００℃以上９００℃以下が好ましく。さらに好ましくは、６５０℃以上８５０℃以下である。熱処理時間は、熱処理温度によるが、通常は、０．５時間〜４時間程度である。
The heat treatment is performed under an inert atmosphere (for example, in argon or vacuum). It is not preferable to perform the heat treatment in an oxidizing atmosphere because the magnetic powder is oxidized and the magnetic properties are deteriorated.
As the heat treatment temperature, an optimum temperature is selected according to the composition of the magnetic powder, molding conditions, and the like so that the residual strain in the green compact is sufficiently removed. Similarly, as the heat treatment time, an optimum temperature is selected according to the composition of the magnetic powder, the heat treatment temperature, and the like so that the residual strain in the green compact is sufficiently removed. In general, when the heat treatment temperature is too low and / or when the heat treatment time is too short, the residual strain is not sufficiently removed. On the other hand, when the heat treatment temperature is too high and / or when the heat treatment time is too long, the magnetic properties of the green compact deteriorate due to the diffusion of the component elements.
For example, in the case of a green compact made of an Fe—Si alloy and a silicon resin, the heat treatment temperature is preferably 600 ° C. or higher and 900 ° C. or lower. More preferably, it is 650 degreeC or more and 850 degrees C or less. The heat treatment time depends on the heat treatment temperature, but is usually about 0.5 to 4 hours.
以上のような方法を用い、かつ、製造条件を最適化することによって、
（１） 電気比抵抗が１×１０1μΩ・ｍ以上であり、かつ、圧環強度が６０ＭＰａ以上である圧粉磁芯、
（２） 電気比抵抗が１×１０2μΩ・ｍ以上であり、かつ、圧環強度が６０ＭＰａ以上である圧粉磁芯、
（３） 電気比抵抗が１×１０1μΩ・ｍ以上であり、かつ、圧環強度が７０ＭＰａ以上である圧粉磁芯、
（４） 電気比抵抗が１×１０2μΩ・ｍ以上であり、かつ、圧環強度が７０ＭＰａ以上である圧粉磁芯、
（５） 電気比抵抗が１×１０1μΩ・ｍ以上であり、かつ、圧環強度が８０ＭＰａ以上である圧粉磁芯、あるいは、
（６） 電気比抵抗が１×１０2μΩ・ｍ以上であり、かつ、圧環強度が８０ＭＰａ以上である圧粉磁芯、
が得られる。
By using the above method and optimizing the manufacturing conditions,
(1) A dust core having an electrical resistivity of 1 × 10 1 μΩ · m or more and a crushing strength of 60 MPa or more,
(2) A dust core having an electrical resistivity of 1 × 10 2 μΩ · m or more and a crushing strength of 60 MPa or more,
(3) A dust core having an electrical resistivity of 1 × 10 1 μΩ · m or more and a crushing strength of 70 MPa or more,
(4) A dust core having an electrical resistivity of 1 × 10 2 μΩ · m or more and a crushing strength of 70 MPa or more,
(5) A dust core having an electrical specific resistance of 1 × 10 1 μΩ · m or more and a crushing strength of 80 MPa or more, or
(6) A dust core having an electrical resistivity of 1 × 10 2 μΩ · m or more and a crushing strength of 80 MPa or more,
Is obtained.
［３． 圧粉磁芯及びその製造方法の作用］
圧粉磁芯は、磁性粉末と絶縁皮膜で構成されるが、磁性粉末の形状は、圧粉磁芯の特性に影響を与える。一般に、低損失の圧粉磁芯を得るためには、球状の磁性粉末を用いるのが好ましい。一方、磁性粉末の形状が球形に近づくほど、粒子同士の絡み合いが起こらないために、圧粉磁芯の機械的強度が低下する。従って、従来の方法をそのまま球形の磁性粉末に適用すると、圧粉磁芯の機械的強度が低下する。
[3. Action of dust core and manufacturing method thereof]
The dust core is composed of a magnetic powder and an insulating film, but the shape of the magnetic powder affects the characteristics of the dust core. In general, in order to obtain a low-loss dust core, it is preferable to use a spherical magnetic powder. On the other hand, the closer the shape of the magnetic powder is to a spherical shape, the more the particles are not entangled with each other, so the mechanical strength of the dust core decreases. Therefore, when the conventional method is applied to the spherical magnetic powder as it is, the mechanical strength of the dust core is reduced.
これに対し、本願発明者らは、特に粉末同士の絡み合いが期待できない球形又は球形に近い粉末において、圧粉磁芯の強度が低下する原因を調査した結果、絶縁皮膜中に生成したＣ相が圧粉磁芯の強度を低下させていることを見出した。
すなわち、圧粉磁芯の絶縁皮膜には、耐熱性の点からシリコン系樹脂を用いるのが一般的である。シリコン系樹脂は、通常、希釈溶媒として芳香族系の有機溶媒が用いられている。そのため、シリコン系樹脂をＳｉＯy系絶縁体に変性させるために、圧粉体を高温で熱処理すると、粒界には、芳香族系の有機溶媒が炭化することにより生成するＣ相が生成する場合がある。粒界に生成したＣ相は、圧粉磁芯の強度を低下させる原因となる。
これに対し、シリコン系樹脂を低沸点溶媒で希釈し、この溶液を用いて磁性粉末の表面を樹脂で被覆すると、球形又は球形に近い磁性粉末を用いた場合であっても、機械的強度の高い圧粉磁芯が得られる。これは、芳香族系の有機溶媒で希釈されたシリコン系樹脂にさらに低沸点溶媒を添加すると、混合物を乾燥する際に共沸によって芳香族系の有機溶媒がほぼ完全に除去され、磁性粉末の粒界にＣ相が生成しにくくなるためと考えられる。
On the other hand, the inventors of the present application investigated the cause of the decrease in the strength of the dust core in a spherical or near-spherical powder, in particular, where entanglement between the powders cannot be expected. It has been found that the strength of the dust core is reduced.
That is, a silicon resin is generally used for the insulating film of the dust core from the viewpoint of heat resistance. In the case of a silicon resin, an aromatic organic solvent is usually used as a dilution solvent. Therefore, when the green compact is heat-treated at a high temperature in order to denature the silicon-based resin into the SiO y- based insulator, a C phase is generated at the grain boundary due to carbonization of the aromatic organic solvent. There is. The C phase generated at the grain boundary causes a reduction in the strength of the dust core.
In contrast, when the silicon-based resin is diluted with a low-boiling solvent and the surface of the magnetic powder is coated with the resin using this solution, the mechanical strength is improved even when a spherical or nearly spherical magnetic powder is used. A high dust core is obtained. This is because when a low boiling point solvent is further added to a silicon resin diluted with an aromatic organic solvent, the aromatic organic solvent is almost completely removed by azeotropic distillation when the mixture is dried. This is thought to be due to the difficulty in forming the C phase at the grain boundaries.
（実施例１、比較例１、２）
［１． 試料の作製］
磁性粉末には、Ｆｅ−Ｓｉ系（Ｓｉ量：０．９〜１．２ｍａｓｓ％）のガス水アトマイズ粉末（１０６〜２１２μｍ）を用いた。所定量（磁性粉末に対して、固形分で０．１〜０．８ｍａｓｓ％）の市販シリコン系樹脂にアセトンを加えて希釈し、これを磁性粉末に加えて混合した。混合後、アセトンの沸点以下の温度で乾燥させ、圧粉磁芯用の粉末を得た。この粉末を金型潤滑温間高圧成形法により、特性評価用の試験片（実施例１）を作製した。成形条件は、以下の通りである。
形状： φ３９ｍｍ×φ３０ｍｍ、高さ５ｍｍ
成形圧力： １５６８ＭＰａ
成形金型温度： ７０℃
金型潤滑剤： 水分散ステアリン酸リチウムを金型表面に吹き付け塗布
金型： ダイス鋼製、バンドヒーターにより加熱。
(Example 1, Comparative Examples 1 and 2)
[1. Preparation of sample]
As the magnetic powder, Fe—Si-based (Si content: 0.9 to 1.2 mass%) gas water atomized powder (106 to 212 μm) was used. Acetone was added to a predetermined amount (0.1 to 0.8 mass% in solid content of the magnetic powder) of a commercially available silicon-based resin to dilute, and this was added to the magnetic powder and mixed. After mixing, the mixture was dried at a temperature lower than the boiling point of acetone to obtain a powder for a dust core. A test piece (Example 1) for property evaluation was produced from this powder by a die lubrication warm high pressure molding method. The molding conditions are as follows.
Shape: φ39mm × φ30mm, height 5mm
Molding pressure: 1568 MPa
Mold temperature: 70 ° C
Mold lubricant: Water-dispersed lithium stearate is sprayed on the mold surface. Mold: Die steel, heated by a band heater.
成形後、試料は、歪み取りのために、真空雰囲気中又は窒素雰囲気中、７５０℃×０．５ｈの熱処理を行った。
また、希釈溶媒として、アセトンに代えてメタノール（沸点：６４．６５℃、比較例１）、又は２−プロパノール（沸点：８２．７℃、比較例２）を用いた以外は、実施例１と同様の手順に従い、特性評価用の試験片を作製した。
After molding, the sample was heat-treated at 750 ° C. × 0.5 h in a vacuum atmosphere or a nitrogen atmosphere to remove strain.
Further, Example 1 was used except that methanol (boiling point: 64.65 ° C., Comparative Example 1) or 2-propanol (boiling point: 82.7 ° C., Comparative Example 2) was used as a dilution solvent instead of acetone. According to the same procedure, a test piece for characteristic evaluation was produced.
［２． 試験方法］
得られた試験片を用いて、圧環強度及び電気抵抗を測定した。電気抵抗は、マイクロオームメーターを使用し、４端子法で測定した。
さらに、ＳＥＭ／ＥＤＸを用いて、絶縁皮膜中の最大Ｃ量を測定した。
[2. Test method]
The crushing strength and electrical resistance were measured using the obtained test piece. The electrical resistance was measured by a 4-terminal method using a micro ohm meter.
Furthermore, the maximum amount of C in the insulating film was measured using SEM / EDX.
［３． 結果］
図１に、使用した希釈溶媒と絶縁皮膜中の最大Ｃ量との関係を示す。希釈溶媒としてメタノール及び２−プロパノールを用いた場合、いずれも最大Ｃ量は８０ａｔ％以上であった。これに対し、希釈溶媒としてアセトンを用いた場合（樹脂添加量＝０．２ｗｔ％、Ｖ／Ｗ比＝５０）、最大Ｃ量は１０ａｔ％以下であった。
図２の左上図及び左下図に、希釈溶媒として２−プロパノールを用いた試験片の絶縁皮膜の反射電子像（２視野）を示す。また、図２の右上図及び左上図に、希釈溶媒としてアセトンを用いた試験片の絶縁皮膜の反射電子像（２視野）を示す。図２より、希釈溶媒として２−プロパノールを用いた場合、絶縁皮膜中に多量のＣ相が認められるのに対し、希釈溶媒としてアセトンを用いた場合、絶縁皮膜中に粗大なＣ相がほとんど認められないことがわかる。希釈溶媒としてアセトンを用いた試料の絶縁皮膜中のＣ量は、アセトン量等にもよるが、５〜２０ａｔ％であった。
[3. result]
FIG. 1 shows the relationship between the diluted solvent used and the maximum amount of C in the insulating film. When methanol and 2-propanol were used as the diluting solvent, the maximum amount of C was 80 at% or more in both cases. On the other hand, when acetone was used as a dilution solvent (resin addition amount = 0.2 wt%, V / W ratio = 50), the maximum C amount was 10 at% or less.
The upper left figure and the lower left figure in FIG. 2 show reflected electron images (two fields of view) of the insulating film of the test piece using 2-propanol as the diluent solvent. Moreover, the upper right figure of FIG. 2 and the upper left figure show the reflected-electron image (2 visual fields) of the insulating film of the test piece which used acetone as a dilution solvent. From FIG. 2, when 2-propanol is used as a diluting solvent, a large amount of C phase is observed in the insulating film, whereas when acetone is used as the diluting solvent, almost coarse C phase is observed in the insulating film. I can't understand. The amount of C in the insulating film of the sample using acetone as a dilution solvent was 5 to 20 at%, although it depends on the amount of acetone and the like.
図３に、絶縁皮膜中の最大Ｃ量と圧環強度との関係を示す。図３より、絶縁皮膜中の最大Ｃ量が少なくなるほど、圧環強度が増大することがわかる。
図４に、樹脂１ｇに対するアセトン量（ｃｃ）（すなわち、Ｖ／Ｗ比）と圧環強度との関係を示す。図４より、Ｖ／Ｗ比をある一定の範囲とすると、圧環強度が極大となることがわかる。
図５に、樹脂添加量と圧環強度との関係を示す。図５より、樹脂添加量が多くなるほど、圧環強度が増大することがわかる。
FIG. 3 shows the relationship between the maximum amount of C in the insulating film and the crushing strength. FIG. 3 shows that the crushing strength increases as the maximum amount of C in the insulating film decreases.
FIG. 4 shows the relationship between the amount of acetone (cc) (ie, V / W ratio) and the crushing strength with respect to 1 g of resin. FIG. 4 shows that the crushing strength becomes maximum when the V / W ratio is in a certain range.
FIG. 5 shows the relationship between the resin addition amount and the crushing strength. FIG. 5 shows that the crushing strength increases as the resin addition amount increases.
さらに、図６に、電気比抵抗と圧環強度との関係を示す。比較例１、２の場合、樹脂添加量や溶媒の種類・希釈量等により多少のばらつきがあるが、圧環強度は、ほとんど６０ＭＰａ未満であった。これに対し、希釈溶媒としてアセトンを用いた場合、樹脂添加量や溶媒の希釈量等によらず、６０ＭＰａ以上の圧環強度が安定して得られた。図６より、樹脂添加量やアセトンの希釈量等を最適化することによって、粒子形状が球形に近いガス水アトマイズ粉末を用いた場合であっても、圧環強度が７０ＭＰａ以上、８０ＭＰａ以上、あるいは９０ＭＰａ以上である圧粉磁芯が得られることがわかる。 Further, FIG. 6 shows the relationship between the electrical specific resistance and the crushing strength. In the case of Comparative Examples 1 and 2, the crushing strength was almost less than 60 MPa, although there were some variations depending on the amount of resin added, the type of solvent, the amount of dilution, and the like. On the other hand, when acetone was used as the dilution solvent, a crushing strength of 60 MPa or more was stably obtained regardless of the resin addition amount, the solvent dilution amount, and the like. From FIG. 6, by optimizing the resin addition amount, the dilution amount of acetone, etc., the crushing strength is 70 MPa or more, 80 MPa or more, or 90 MPa even when the gas water atomized powder having a particle shape close to a sphere is used. It turns out that the dust core which is the above is obtained.
以上、本発明の実施の形態について詳細に説明したが、本発明は上記実施の形態に何ら限定されるものではなく、本発明の要旨を逸脱しない範囲内で種々の改変が可能である。 Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention.
本発明に係る圧粉磁芯及びその製造方法は、モータ、トランス、ＤＣソレノイドアクチュエータ、インバータ、スイッチング素子、ノイズフィルタ等の各種電気機器用の磁芯及びその製造方法として用いることができる。 The dust core and the manufacturing method thereof according to the present invention can be used as a magnetic core for various electric devices such as a motor, a transformer, a DC solenoid actuator, an inverter, a switching element, a noise filter, and the manufacturing method thereof.
Claims (12)
前記磁性粉末を被覆する絶縁皮膜とを備え、
前記絶縁皮膜は、次の（１）式で表される組成を有する圧粉磁芯。
(Ｓｉ−Ｏ)100-xＣx （０＜ｘ(ａｔ％)≦２０） ・・・（１） Magnetic powder made of soft magnetic material;
An insulating film covering the magnetic powder,
The insulating film is a dust core having a composition represented by the following formula (1).
(Si—O) 100-x C x (0 <x (at%) ≦ 20) (1)
圧環強度が６０ＭＰａ以上である
請求項１に記載の圧粉磁芯。 The specific resistance is 1 × 10 1 μΩ · m or more,
The dust core according to claim 1, wherein the crushing strength is 60 MPa or more.
前記磁性粉末を被覆する絶縁皮膜とを備え、
前記絶縁皮膜中の最大Ｃ量が５０ａｔ％以下である圧粉磁芯。 Magnetic powder made of soft magnetic material;
An insulating film covering the magnetic powder,
A dust core in which the maximum amount of C in the insulating film is 50 at% or less.
圧環強度が６０ＭＰａ以上である
請求項４に記載の圧粉磁芯。 The specific resistance is 1 × 10 1 μΩ · m or more,
The dust core according to claim 4, wherein the green crushing strength is 60 MPa or more.
前記磁性粉末を被覆する絶縁皮膜とを備え、
前記絶縁皮膜は、次の（１）式で表される組成を有し、
前記絶縁皮膜中の最大Ｃ量が５０ａｔ％以下である圧粉磁芯。
(Ｓｉ−Ｏ)100-xＣx （０＜ｘ(ａｔ％)≦２０） ・・・（１） Magnetic powder made of soft magnetic material;
An insulating film covering the magnetic powder,
The insulating film has a composition represented by the following formula (1):
A dust core in which the maximum amount of C in the insulating film is 50 at% or less.
(Si—O) 100-x C x (0 <x (at%) ≦ 20) (1)
圧環強度が６０ＭＰａ以上である
請求項７に記載の圧粉磁芯。 The specific resistance is 1 × 10 1 μΩ · m or more,
The dust core according to claim 7, wherein the crushing strength is 60 MPa or more.
前記混合工程で得られた混合物から溶媒を除去する乾燥工程と、
前記乾燥工程で得られた粉末を成形する成形工程と、
を備えた圧粉磁芯の製造方法。 A mixing step of mixing a magnetic powder made of a soft magnetic material, a silicon-based resin, and a low boiling point solvent having a boiling point of 60 ° C. or less;
A drying step for removing the solvent from the mixture obtained in the mixing step;
A molding step of molding the powder obtained in the drying step;
A method for producing a dust core comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2007258134A JP4733790B2 (en) | 2007-10-01 | 2007-10-01 | Powder magnetic core and method for manufacturing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2007258134A JP4733790B2 (en) | 2007-10-01 | 2007-10-01 | Powder magnetic core and method for manufacturing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2009088362A true JP2009088362A (en) | 2009-04-23 |
| JP4733790B2 JP4733790B2 (en) | 2011-07-27 |
Family
ID=40661363
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2007258134A Expired - Fee Related JP4733790B2 (en) | 2007-10-01 | 2007-10-01 | Powder magnetic core and method for manufacturing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4733790B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011146681A (en) * | 2009-10-06 | 2011-07-28 | Fuji Electric Co Ltd | Dust core and method of manufacturing the same |
| WO2023190373A1 (en) * | 2022-03-29 | 2023-10-05 | 住友ベークライト株式会社 | Soft magnetic material, molded article, and production method for molded article |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09260126A (en) * | 1996-01-16 | 1997-10-03 | Tdk Corp | Iron powder for dust core, dust core and manufacture thereof |
| JP2000277314A (en) * | 1999-03-23 | 2000-10-06 | Tdk Corp | Dust core and method of producing the same |
| JP2007013069A (en) * | 2005-05-31 | 2007-01-18 | Mitsubishi Materials Pmg Corp | METHOD FOR PRODUCING SOFT MAGNETIC POWDER COATED WITH OXIDE CONTAINING Mg AND Si |
| JP2007042883A (en) * | 2005-08-03 | 2007-02-15 | Toda Kogyo Corp | Soft magnetic material, its manufacturing method, and dust core containing same |
-
2007
- 2007-10-01 JP JP2007258134A patent/JP4733790B2/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09260126A (en) * | 1996-01-16 | 1997-10-03 | Tdk Corp | Iron powder for dust core, dust core and manufacture thereof |
| JP2000277314A (en) * | 1999-03-23 | 2000-10-06 | Tdk Corp | Dust core and method of producing the same |
| JP2007013069A (en) * | 2005-05-31 | 2007-01-18 | Mitsubishi Materials Pmg Corp | METHOD FOR PRODUCING SOFT MAGNETIC POWDER COATED WITH OXIDE CONTAINING Mg AND Si |
| JP2007042883A (en) * | 2005-08-03 | 2007-02-15 | Toda Kogyo Corp | Soft magnetic material, its manufacturing method, and dust core containing same |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011146681A (en) * | 2009-10-06 | 2011-07-28 | Fuji Electric Co Ltd | Dust core and method of manufacturing the same |
| WO2023190373A1 (en) * | 2022-03-29 | 2023-10-05 | 住友ベークライト株式会社 | Soft magnetic material, molded article, and production method for molded article |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4733790B2 (en) | 2011-07-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5368686B2 (en) | Soft magnetic material, dust core, method for producing soft magnetic material, and method for producing dust core | |
| JP5650928B2 (en) | SOFT MAGNETIC MATERIAL, MOLDED BODY, DUST CORE, ELECTRONIC COMPONENT, SOFT MAGNETIC MATERIAL MANUFACTURING METHOD, AND DUST CORE MANUFACTURING METHOD | |
| JP5067544B2 (en) | Reactor core, manufacturing method thereof, and reactor | |
| JP5218567B2 (en) | Manufacturing method of dust core | |
| JP2006024869A (en) | Dust core and manufacturing method thereof | |
| US20230081183A1 (en) | Dust core, method for manufacturing dust core, inductor including dust core, and electronic/electric device including inductor | |
| CN106663513B (en) | Magnetic core, the manufacturing method of magnetic core and coil component | |
| JP5372481B2 (en) | Powder magnetic core and manufacturing method thereof | |
| JP2010251696A (en) | Soft magnetic powder core and method of manufacturing the same | |
| JP4750471B2 (en) | Low magnetostrictive body and dust core using the same | |
| JP6056862B2 (en) | Iron powder for dust core and insulation coated iron powder for dust core | |
| JP2011243830A (en) | Powder magnetic core and method for manufacturing the same | |
| JP4733790B2 (en) | Powder magnetic core and method for manufacturing the same | |
| JP2012151179A (en) | Dust core | |
| JP6620643B2 (en) | Compacted magnetic body, magnetic core and coil type electronic parts | |
| JP6556780B2 (en) | Powder magnetic core, powder for magnetic core, and production method thereof | |
| JP5094780B2 (en) | Dust core | |
| JP2005281805A (en) | Method for producing soft magnetic material, soft magnetic powder and dust core | |
| JP2008297622A (en) | Soft magnetic material, dust core, method for manufacturing soft magnetic material and method for manufacturing dust core | |
| JP2021093405A (en) | Method of manufacturing dust core | |
| JP2005093350A (en) | Insulation coating, powder for magnetic core, and dust core, and manufacturing method of those | |
| KR102644062B1 (en) | Iron-based soft magnetic powder for dust cores, dust core, and methods of producing same | |
| TW202320090A (en) | Mixture for manufacturing iron-based sintered body, iron-based sintered body, and manufacturing method of iron-based sintered body in which the iron-based sintered body has high magnetic properties and high mechanical properties is obtained | |
| JP2021174943A (en) | Powder magnetic core and manufacturing method thereof | |
| JP2021077762A (en) | Dust core |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20090820 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20100906 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20100910 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20101104 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20110411 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20110423 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140428 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 4733790 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313532 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140428 Year of fee payment: 3 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |