JP2017152529A - Magnetic core and coil member - Google Patents
Magnetic core and coil member Download PDFInfo
- Publication number
- JP2017152529A JP2017152529A JP2016033244A JP2016033244A JP2017152529A JP 2017152529 A JP2017152529 A JP 2017152529A JP 2016033244 A JP2016033244 A JP 2016033244A JP 2016033244 A JP2016033244 A JP 2016033244A JP 2017152529 A JP2017152529 A JP 2017152529A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- magnetic core
- particles
- core
- sample
- 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
- 239000002245 particle Substances 0.000 claims abstract description 67
- 239000006249 magnetic particle Substances 0.000 claims abstract description 66
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 60
- 230000005415 magnetization Effects 0.000 claims abstract description 34
- 230000035699 permeability Effects 0.000 claims abstract description 25
- 230000004907 flux Effects 0.000 claims abstract description 17
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910052742 iron Inorganic materials 0.000 claims abstract description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 6
- 239000010941 cobalt Substances 0.000 claims abstract description 6
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 6
- 229910000640 Fe alloy Inorganic materials 0.000 claims abstract description 4
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims abstract description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 3
- 229910052796 boron Inorganic materials 0.000 claims abstract description 3
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 3
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 3
- 239000010703 silicon Substances 0.000 claims abstract description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 12
- 239000000956 alloy Substances 0.000 claims description 12
- 229920006395 saturated elastomer Polymers 0.000 abstract 2
- 239000000843 powder Substances 0.000 description 18
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 16
- 239000011258 core-shell material Substances 0.000 description 7
- 239000002105 nanoparticle Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 5
- 238000010298 pulverizing process Methods 0.000 description 5
- 238000003917 TEM image Methods 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- QGLWBTPVKHMVHM-KTKRTIGZSA-N (z)-octadec-9-en-1-amine Chemical compound CCCCCCCC\C=C/CCCCCCCCN QGLWBTPVKHMVHM-KTKRTIGZSA-N 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 239000004094 surface-active agent Substances 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- POILWHVDKZOXJZ-ARJAWSKDSA-M (z)-4-oxopent-2-en-2-olate Chemical compound C\C([O-])=C\C(C)=O POILWHVDKZOXJZ-ARJAWSKDSA-M 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 229910002796 Si–Al Inorganic materials 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- SNRUBQQJIBEYMU-UHFFFAOYSA-N dodecane Chemical compound CCCCCCCCCCCC SNRUBQQJIBEYMU-UHFFFAOYSA-N 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000000700 radioactive tracer Substances 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 229910052814 silicon oxide Inorganic materials 0.000 description 2
- 238000005979 thermal decomposition reaction Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910000531 Co alloy Inorganic materials 0.000 description 1
- 229910020639 Co-Al Inorganic materials 0.000 description 1
- 229910020675 Co—Al Inorganic materials 0.000 description 1
- 229910020711 Co—Si Inorganic materials 0.000 description 1
- 229910017061 Fe Co Inorganic materials 0.000 description 1
- 229910017082 Fe-Si Inorganic materials 0.000 description 1
- 229910017133 Fe—Si Inorganic materials 0.000 description 1
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000005307 ferromagnetism Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- WTFXARWRTYJXII-UHFFFAOYSA-N iron(2+);iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[Fe+2].[Fe+3].[Fe+3] WTFXARWRTYJXII-UHFFFAOYSA-N 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Landscapes
- Soft Magnetic Materials (AREA)
Abstract
Description
本発明は、磁心およびコイル部材に関する。 The present invention relates to a magnetic core and a coil member.
従来、トランス、インダクタ、リアクトル等のコイル部材に用いられる磁心（コア）としては、フェライト、電磁鋼板、鉄系ダスト材などが知られている。近年、コイル部材を利用するスイッチング電源等の高周波化に伴い、上記磁心におけるヒステリシス損失、渦電流損失が増加しやすくなっている。そのため、損失を抑制する観点から、ナノ粒子を用いた磁心が提案されている。 Conventionally, as magnetic cores (cores) used for coil members such as transformers, inductors, and reactors, ferrite, electromagnetic steel sheets, iron-based dust materials, and the like are known. In recent years, hysteresis loss and eddy current loss in the magnetic core are likely to increase as the frequency of switching power supplies using coil members increases. Therefore, a magnetic core using nanoparticles has been proposed from the viewpoint of suppressing loss.
例えば、特許文献１には、５０ｎｍ未満の粒径を有しており、コアが超常磁性の酸化鉄であり、シェルが酸化ケイ素であるコアシェルナノ粒子を含む磁心、これを用いたトランス等のコイル部材が開示されている。 For example, Patent Document 1 discloses a magnetic core including core-shell nanoparticles having a particle diameter of less than 50 nm, a core made of superparamagnetic iron oxide, and a shell made of silicon oxide, and a coil such as a transformer using the core. A member is disclosed.
しかしながら、上記コアシェルナノ粒子は、コアが超常磁性の酸化鉄より構成されている。酸化鉄は、飽和磁化が低い。また、上記コアシェルナノ粒子は、コアを構成する酸化鉄とシェルを構成する酸化ケイ素との複合体である。そのため、上記コアシェルナノ粒子を用いた磁心は、酸化鉄の含有量が低くなる。それ故、上記コアシェルナノ粒子を用いた磁心は、飽和磁束密度が低い。また、超常磁性の本質として、比透磁率が低い。したがって、上記コアシェルナノ粒子を用いた磁心は、損失が小さいものの、飽和磁束密度、比透磁率が低く、実用化が難しい。 However, the core-shell nanoparticles are composed of iron oxide whose core is superparamagnetic. Iron oxide has a low saturation magnetization. Moreover, the said core-shell nanoparticle is a composite_body | complex of the iron oxide which comprises a core, and the silicon oxide which comprises a shell. Therefore, the magnetic core using the core-shell nanoparticles has a low iron oxide content. Therefore, the magnetic core using the core-shell nanoparticles has a low saturation magnetic flux density. Moreover, the relative permeability is low as the essence of superparamagnetism. Therefore, although the magnetic core using the core-shell nanoparticles has a small loss, it has a low saturation magnetic flux density and a low relative magnetic permeability and is difficult to put into practical use.
本発明は、かかる課題に鑑みてなされたものであり、損失が小さく、飽和磁束密度および比透磁率が高い磁心、これを備えたコイル部材を提供しようとするものである。 The present invention has been made in view of such problems, and an object of the present invention is to provide a magnetic core having a small loss, a high saturation magnetic flux density and a high relative magnetic permeability, and a coil member including the magnetic core.
本発明の一態様は、１０ｎｍ以下の粒径を有し、飽和磁化８５ｅｍｕ／ｇ以上である磁性粒子より構成されており、当該磁性粒子の体積分率が２０％以上である、磁心にある。 One embodiment of the present invention is a magnetic core having a particle diameter of 10 nm or less and composed of magnetic particles having a saturation magnetization of 85 emu / g or more, and the volume fraction of the magnetic particles is 20% or more.
本発明の他の態様は、上記磁心を有する、コイル部材にある。 Another aspect of the present invention resides in a coil member having the magnetic core.
上記磁心は、磁性粒子の粒径が１０ｎｍ以下である。そのため、上記磁心は、超常磁性が発現され、損失を小さくすることができる。また、上記磁心は、磁性粒子の飽和磁化が８５ｅｍｕ／ｇ以上である。当該磁性粒子は、酸化鉄粒子に比べ、飽和磁化が大きい。そのため、上記磁心は、高い飽和磁束密度を発現することができる。また、上記磁心は、磁性粒子の体積分率が２０％以上である。そのため、上記磁心は、高い比透磁率を発現することができる。これは、以下によるものと考えられる。すなわち、上記磁心では、飽和磁化の高い磁性粒子が高密度で存在している。そのため、高飽和磁化の磁性粒子の粒子間距離が短くなる。そのため、上記磁心は、有効な磁場として、外部磁場に加えて、隣り合う磁性粒子から発生する双極子磁場も加わる。その結果、上記磁心は、磁心全体として比透磁率を向上させることができる。 The magnetic core has a magnetic particle size of 10 nm or less. Therefore, the magnetic core exhibits superparamagnetism and can reduce loss. The magnetic core has a saturation magnetization of magnetic particles of 85 emu / g or more. The magnetic particles have a larger saturation magnetization than iron oxide particles. Therefore, the magnetic core can express a high saturation magnetic flux density. The magnetic core has a volume fraction of magnetic particles of 20% or more. Therefore, the magnetic core can express a high relative permeability. This is considered to be due to the following. That is, in the magnetic core, magnetic particles having a high saturation magnetization exist at a high density. For this reason, the inter-particle distance of magnetic particles with high saturation magnetization is shortened. For this reason, the magnetic core also applies a dipole magnetic field generated from adjacent magnetic particles as an effective magnetic field in addition to an external magnetic field. As a result, the magnetic core can improve the relative magnetic permeability as a whole.
上記コイル部材は、上述したように、損失が小さく、飽和磁束密度および比透磁率が高い磁心を有している。そのため、上記コイル部材は、高周波化に対応しやすい。 As described above, the coil member has a magnetic core with low loss and high saturation magnetic flux density and high relative magnetic permeability. Therefore, the coil member can easily cope with high frequency.
（実施形態１）
実施形態１の磁心について説明する。本実施形態の磁心は、１０ｎｍ以下の粒径を有し、飽和磁化８５ｅｍｕ／ｇ以上である磁性粒子より構成されており、当該磁性粒子の体積分率が２０％以上である。以下、これを詳説する。
(Embodiment 1)
The magnetic core of Embodiment 1 will be described. The magnetic core of the present embodiment is composed of magnetic particles having a particle diameter of 10 nm or less and a saturation magnetization of 85 emu / g or more, and the volume fraction of the magnetic particles is 20% or more. This will be described in detail below.
上記磁心において、磁性粒子の粒径が１０ｎｍを超えると、超常磁性が発現されなくなり、損失を小さくすることが難しくなる。磁性粒子の粒径は、損失低減を確実なものとするなどの観点から、好ましくは１０ｎｍ未満、より好ましくは９ｎｍ以下、さらに好ましくは８ｎｍ以下、さらにより好ましくは７ｎｍ以下、さらにより一層好ましくは６．５ｎｍ未満、最も好ましくは６ｎｍ以下とすることができる。磁性粒子の粒径の下限は、磁性粒子の製造性などの観点から、０．５ｎｍ以上とすることができる。なお、磁性粒子の粒径は、磁心を粉砕した粉末を透過型電子顕微鏡にて観察し、得られたＴＥＭ像より任意に選択される磁性粒子２００個の粒子径の平均値である。 In the magnetic core, when the particle size of the magnetic particles exceeds 10 nm, superparamagnetism is not expressed and it is difficult to reduce the loss. The particle size of the magnetic particles is preferably less than 10 nm, more preferably 9 nm or less, still more preferably 8 nm or less, even more preferably 7 nm or less, and even more preferably 6 from the viewpoint of ensuring loss reduction. Less than 5 nm, most preferably 6 nm or less. The lower limit of the particle size of the magnetic particles can be 0.5 nm or more from the viewpoint of the productivity of the magnetic particles. The particle size of the magnetic particles is an average value of the particle sizes of 200 magnetic particles arbitrarily selected from a TEM image obtained by observing a powder obtained by pulverizing the magnetic core with a transmission electron microscope.
上記磁心において、磁性粒子の飽和磁化は、酸化鉄よりも高い飽和磁化を得ることを確実にするなどの観点から、好ましくは８７ｅｍｕ／ｇ以上、より好ましくは９０ｅｍｕ／ｇ以上、さらに好ましくは９２ｅｍｕ／ｇ以上、さらにより好ましくは９５ｅｍｕ／ｇ以上、さらにより一層好ましくは１００ｅｍｕ／ｇ以上とすることができる。なお、磁性粒子の飽和磁化は、磁心を粉砕した粉末について、振動試料型磁力計（ＶＳＭ）を用いて測定される値である。 In the above magnetic core, the saturation magnetization of the magnetic particles is preferably 87 emu / g or more, more preferably 90 emu / g or more, and still more preferably 92 emu / g from the viewpoint of ensuring that saturation magnetization higher than that of iron oxide is obtained. g or more, even more preferably 95 emu / g or more, even more preferably 100 emu / g or more. The saturation magnetization of the magnetic particles is a value measured with a vibrating sample magnetometer (VSM) for the powder obtained by pulverizing the magnetic core.
上記磁心において、磁性粒子の体積分率が２０％未満になると、比透磁率の向上効果が得られ難くなる。これは、高飽和磁化の磁性粒子の粒子間距離が長くなり、有効な磁場として、外部磁場に双極子磁場が加わらなくなるためであると考えられる。磁性粒子の体積分率は、比透磁率向上などの観点から、好ましくは２５％以上、より好ましくは３０％以上、さらに好ましくは３５％以上、さらにより好ましくは４０％以上とすることができる。また、磁性粒子の体積分率は、製造性、損失低減などの観点から、８５％以下とすることができる。なお、磁性粒子の体積分率は、次のようにして測定される値である。磁性粒子を構成する材料を特定する。磁心が磁性粒子を構成する材料１００％で構成されていると仮定した場合の磁心の密度ρ０を求める。つまり、密度ρ０は、磁性粒子の真密度である。磁心の実際の密度ρ１を測定する。つまり、密度ρ１は、磁心のみかけ密度である。磁性粒子の体積分率を、ρ１／ρ０×１００より算出する。なお、磁心が２種類以上の磁性粒子から構成される場合、他の分析等から２種類以上の磁性粒子の体積比を求めることにより、磁心全体の中での磁性粒子の体積分率を求めることができる。例えば、磁性粒子Ａおよび磁性粒子Ｂの２種類の磁性粒子から磁心が構成されている場合について、磁心全体の中での磁性粒子の体積分率を求める方法を以下に示す。磁性粒子Ａと磁性粒子Ｂの体積比がＶＡ：ＶＢであり、Ａ材料の真密度がρＡ、Ｂ材料の真密度がρＢであった場合、密度ρ０＝ρＡ×ＶＡ／（ＶＡ＋ＶＢ）＋ρＢ×ＶＢ／（ＶＡ＋ＶＢ）として求めることができ、磁性粒子の磁心の中での体積分率をρ１／ρ０×１００より算出することができる。磁性粒子が２種類以上の合金（例えば、コアシェル構造をとり、コア部が合金Ａ，シェル部が合金Ｂである場合等）から構成される場合も同様である。 In the magnetic core, when the volume fraction of the magnetic particles is less than 20%, it is difficult to obtain the effect of improving the relative magnetic permeability. This is thought to be because the inter-particle distance of magnetic particles with high saturation magnetization becomes longer, and the dipole magnetic field is not applied to the external magnetic field as an effective magnetic field. The volume fraction of the magnetic particles is preferably 25% or more, more preferably 30% or more, still more preferably 35% or more, and even more preferably 40% or more, from the viewpoint of improving the relative permeability. The volume fraction of the magnetic particles can be 85% or less from the viewpoints of manufacturability and loss reduction. The volume fraction of magnetic particles is a value measured as follows. The material constituting the magnetic particle is specified. The density ρ 0 of the magnetic core is obtained when it is assumed that the magnetic core is made of 100% of the material constituting the magnetic particles. That is, the density ρ 0 is the true density of the magnetic particles. The actual density ρ 1 of the magnetic core is measured. That is, the density ρ 1 is an apparent density of the magnetic core. The volume fraction of magnetic particles is calculated from ρ 1 / ρ 0 × 100. When the magnetic core is composed of two or more kinds of magnetic particles, the volume fraction of the magnetic particles in the entire magnetic core is obtained by obtaining the volume ratio of the two or more kinds of magnetic particles from other analysis. Can do. For example, in the case where the magnetic core is composed of two types of magnetic particles, magnetic particles A and B, a method for obtaining the volume fraction of the magnetic particles in the entire magnetic core is shown below. When the volume ratio of the magnetic particles A and the magnetic particles B is V A : V B , the true density of the A material is ρ A , and the true density of the B material is ρ B , the density ρ 0 = ρ A × VA / (V A + V B ) + ρ B × V B / (V A + V B ), and the volume fraction in the magnetic core of the magnetic particles can be calculated from ρ 1 / ρ 0 × 100. . The same applies to the case where the magnetic particles are composed of two or more kinds of alloys (for example, a case where the core portion has a core-shell structure, the core portion is alloy A, and the shell portion is alloy B).
上記磁心において、磁性粒子は、鉄、ニッケルおよびコバルトからなる群より選択される少なくとも１種の元素またはこれら元素を含む合金より構成することができる。 In the magnetic core, the magnetic particles can be composed of at least one element selected from the group consisting of iron, nickel and cobalt, or an alloy containing these elements.
磁性粒子は、例えば、鉄、鉄合金、ニッケル、ニッケル合金、コバルト、コバルト合金等より構成することができる。磁性粒子は、具体的には、鉄、または、鉄と、ニッケル、コバルト、シリコン、アルミニウム、炭素、ホウ素および窒素からなる群より選択される少なくとも１種の元素との合金より構成することができる。これらの場合には、酸化鉄粒子に比べ、磁性粒子の飽和磁化が高くなり、損失が小さく、飽和磁束密度の高い磁心を得やすくなる。 The magnetic particles can be composed of, for example, iron, iron alloy, nickel, nickel alloy, cobalt, cobalt alloy, or the like. Specifically, the magnetic particles can be composed of iron or an alloy of iron and at least one element selected from the group consisting of nickel, cobalt, silicon, aluminum, carbon, boron, and nitrogen. . In these cases, compared to iron oxide particles, the saturation magnetization of the magnetic particles is high, the loss is small, and it is easy to obtain a magnetic core with a high saturation magnetic flux density.
より具体的には、磁性粒子は、高飽和磁化、低損失、コスト等の観点から、例えば、Ｆｅ、Ｆｅ−Ｎｉ合金、Ｆｅ−Ｃｏ合金、Ｆｅ−Ｓｉ合金、Ｆｅ−Ｓｉ−Ａｌ合金、Ｆｅ−Ａｌ合金等より構成することができる。また、磁性粒子は、高飽和磁化、低損失等の観点から、例えば、Ｃｏ、Ｃｏ−Ｓｉ合金、Ｃｏ−Ｓｉ−Ａｌ合金、Ｃｏ−Ａｌ合金等より構成することもできる。 More specifically, the magnetic particles are, for example, Fe, Fe—Ni alloy, Fe—Co alloy, Fe—Si alloy, Fe—Si—Al alloy, Fe, etc. from the viewpoint of high saturation magnetization, low loss, cost, and the like. -It can consist of Al alloy etc. In addition, the magnetic particles can be made of, for example, Co, a Co—Si alloy, a Co—Si—Al alloy, a Co—Al alloy, or the like from the viewpoint of high saturation magnetization, low loss, and the like.
上記磁心は、成形体より構成することができる。この場合には、磁心の高密度化により、比透磁率の向上効果を確実なものとすることができる。これは、成形による加圧によって高飽和磁化の磁性粒子の粒子間距離が短くなりやすく、有効な磁場として、外部磁場に加えて双極子磁場が加わりやすくなるためであると考えられる。また、この場合には、磁性粒子が粉末状態で用いられる磁心に比べて、粉末を入れるケースが不要となる。そのため、この場合には、取扱い性に優れた磁心が得られる。 The said magnetic core can be comprised from a molded object. In this case, the effect of improving the relative permeability can be ensured by increasing the density of the magnetic core. This is considered to be because the inter-particle distance of the magnetic particles with high saturation magnetization tends to be shortened by pressurization by molding, and a dipole magnetic field is easily added as an effective magnetic field in addition to the external magnetic field. Further, in this case, a case for putting powder becomes unnecessary as compared with a magnetic core in which magnetic particles are used in a powder state. Therefore, in this case, a magnetic core excellent in handleability can be obtained.
上記磁心は、磁性粒子同士が焼結していないことが好ましい。この場合には、超常磁性が発現されやすくなり、損失の低減に有利な磁心が得られる。なお、磁性粒子の焼結状態は、ＸＲＤ分析から推定されるシェラー粒径の変化や、後述する図５のような磁化の温度依存性から推定される超常磁性転移温度の変化により把握することができる。 The magnetic core is preferably not sintered between magnetic particles. In this case, superparamagnetism is easily developed, and a magnetic core advantageous for reducing loss can be obtained. The sintered state of the magnetic particles can be grasped by the change of the Scherrer particle diameter estimated from the XRD analysis or the change of the superparamagnetic transition temperature estimated from the temperature dependence of the magnetization as shown in FIG. it can.
上記磁心は、具体的には、超常磁性を示し、飽和磁束密度が０．２０Ｔ以上であり、比透磁率が６以上であるとよい。この場合には、損失が小さく、飽和磁束密度および比透磁率が高い磁心を確実に得ることができる。 Specifically, the magnetic core exhibits superparamagnetism, a saturation magnetic flux density of 0.20 T or more, and a relative permeability of 6 or more. In this case, a magnetic core with low loss and high saturation magnetic flux density and high relative magnetic permeability can be obtained with certainty.
磁心の飽和磁束密度は、磁心のサイズ低減などの観点から、好ましくは０．２５Ｔ以上、より好ましくは０．３Ｔ以上、さらに好ましくは０．４Ｔ以上とすることができる。なお、磁心の飽和磁束密度は、磁心の製造性などの観点から、例えば、２．０Ｔ以下とすることができる。また、磁心の比透磁率は、システム設計性の向上などの観点から、好ましくは７以上、より好ましくは８以上、さらに好ましくは１０以上、さらにより好ましくは５０以上、さらにより一層好ましくは１００以上とすることができる。なお、磁心の比透磁率は、双極子磁場の大きさなどの観点から、１００００以下とすることができる。 From the viewpoint of reducing the size of the magnetic core, the saturation magnetic flux density of the magnetic core is preferably 0.25 T or more, more preferably 0.3 T or more, and even more preferably 0.4 T or more. Note that the saturation magnetic flux density of the magnetic core can be set to 2.0 T or less, for example, from the viewpoint of manufacturability of the magnetic core. The relative permeability of the magnetic core is preferably 7 or more, more preferably 8 or more, still more preferably 10 or more, still more preferably 50 or more, and still more preferably 100 or more, from the viewpoint of improving system design. It can be. The relative permeability of the magnetic core can be set to 10,000 or less from the viewpoint of the magnitude of the dipole magnetic field.
上記磁心が超常磁性を有するか否かは、温度（Ｋ）と磁化（ａ．ｕ．）との関係を測定することにより判別することができる。また、磁心の飽和磁束密度は、磁心を粉砕した粉末の飽和磁化と磁心の密度から求めることができる。磁心の比透磁率は、直流ＢＨトレーサーを用いて直流磁気特性を測定することにより得ることができる。 Whether or not the magnetic core has superparamagnetism can be determined by measuring the relationship between temperature (K) and magnetization (au). The saturation magnetic flux density of the magnetic core can be determined from the saturation magnetization of the powder obtained by pulverizing the magnetic core and the density of the magnetic core. The relative permeability of the magnetic core can be obtained by measuring DC magnetic characteristics using a DC BH tracer.
上記磁心は、磁性粒子の粒径が１０ｎｍ以下である。そのため、上記磁心は、超常磁性が発現され、損失を小さくすることができる。また、上記磁心は、磁性粒子の飽和磁化が８５ｅｍｕ／ｇ以上である。当該磁性粒子は、酸化鉄粒子に比べ、飽和磁化が大きい。そのため、上記磁心は、高い飽和磁束密度を発現することができる。また、上記磁心は、磁性粒子の体積分率が２０％以上である。そのため、上記磁心は、高い比透磁率を発現することができる。 The magnetic core has a magnetic particle size of 10 nm or less. Therefore, the magnetic core exhibits superparamagnetism and can reduce loss. The magnetic core has a saturation magnetization of magnetic particles of 85 emu / g or more. The magnetic particles have a larger saturation magnetization than iron oxide particles. Therefore, the magnetic core can express a high saturation magnetic flux density. The magnetic core has a volume fraction of magnetic particles of 20% or more. Therefore, the magnetic core can express a high relative permeability.
（実施形態２）
実施形態２のコイル部材について説明する。本実施形態のコイル部材は、実施形態１に記載の磁心を有している。上記コイル部材としては、具体的には、例えば、リアクトル、トランス、インダクタ等を例示することができる。
(Embodiment 2)
The coil member of Embodiment 2 will be described. The coil member of this embodiment has the magnetic core described in the first embodiment. Specific examples of the coil member include a reactor, a transformer, and an inductor.
上記コイル部材は、１ｋＨｚ〜１ＭＨｚの周波数域で用いることができる。この場合には、１ｋＨｚ〜１ＭＨｚの周波数域において、損失が小さく、飽和磁束密度および比透磁率が高い磁心を有するコイル部材が得られる。 The coil member can be used in a frequency range of 1 kHz to 1 MHz. In this case, in the frequency range of 1 kHz to 1 MHz, a coil member having a magnetic core with low loss and high saturation magnetic flux density and high relative permeability can be obtained.
以下、実験例を用いてより具体的に説明する。
＜実験例＞
Ｆｅ（ＣＯ）５と界面活性剤（オレイルアミン）とを反応させた前駆体を溶媒（ドデカン）中で熱分解することにより、Ｆｅ粒子を合成した。なお、熱分解条件は、２００℃、６０分とした。得られたＦｅ粒子を１０−２Ｔｏｒｒ以下の減圧雰囲気下、２００℃で熱処理し、余分な界面活性剤や有機物を除去し、磁心の作製に用いるＦｅ粒子粉末を得た。得られたＦｅ粒子粉末を２０ＭＰａ、２００℃の条件でホットプレスして成形体（バルク体）とすることにより、試料１の磁心を得た。なお、上記の作業は、Ｆｅ粒子の酸化を防ぐため、酸素濃度と水分濃度とがともに１．０ｐｐｍ以下であるＡｒガス雰囲気のグローブボックス中で行った。
Hereinafter, it demonstrates more concretely using an experiment example.
<Experimental example>
Fe particles were synthesized by thermally decomposing a precursor obtained by reacting Fe (CO) 5 and a surfactant (oleylamine) in a solvent (dodecane). The thermal decomposition conditions were 200 ° C. and 60 minutes. The obtained Fe particles were heat-treated at 200 ° C. under a reduced pressure atmosphere of 10 −2 Torr or less to remove excess surfactants and organic substances, thereby obtaining Fe particle powders used for producing a magnetic core. The obtained Fe particle powder was hot pressed under the conditions of 20 MPa and 200 ° C. to obtain a molded body (bulk body), whereby a magnetic core of Sample 1 was obtained. In addition, in order to prevent the oxidation of Fe particle | grains, said operation | work was performed in the glove box of Ar gas atmosphere whose oxygen concentration and water concentration are both 1.0 ppm or less.
上記にて得られたＦｅ粒子粉末の大気曝露後のＴＥＭ像を図１に示す。なお、透過型電子顕微鏡で観察する際に、Ｆｅ粒子粉末を大気中で曝露しているため、Ｆｅは酸素と反応し、Ｆｅ３Ｏ４に変化している。その結果、観察される粒子の粒径は、実際のＦｅ粒子の粒径より大きくなっている。観察される粒子がＸＲＤ分析より全てＦｅ３Ｏ４になっていることから、大気曝露前のＦｅ粒子の粒径を求めることができる。得られたＴＥＭ像より任意に選択されるＦｅ３Ｏ４粒子２００個の粒子径の平均値から、酸化前のＦｅ粒子の粒径は、約４．０ｎｍであると分析された。また、図２に示されるように、作製した磁心の形状は、外径１３．５ｍｍ、内径６．５ｍｍ、高さ２．８ｍｍのリング形状である。 A TEM image of the Fe particle powder obtained above after exposure to the atmosphere is shown in FIG. At the time of observation with a transmission electron microscope, since the exposure in air to Fe particles, Fe reacts with oxygen was changed into Fe 3 O 4. As a result, the particle size of the observed particles is larger than the actual particle size of Fe particles. Since all of the observed particles are Fe 3 O 4 by XRD analysis, the particle size of the Fe particles before exposure to the atmosphere can be determined. From the average value of the particle diameters of 200 Fe 3 O 4 particles arbitrarily selected from the obtained TEM image, the particle diameter of the Fe particles before oxidation was analyzed to be about 4.0 nm. In addition, as shown in FIG. 2, the shape of the produced magnetic core is a ring shape having an outer diameter of 13.5 mm, an inner diameter of 6.5 mm, and a height of 2.8 mm.
なお、上記Ｆｅ（ＣＯ）５と界面活性剤（オレイルアミン）との混合比や熱分解条件を変更した点以外は試料１の磁心の作製と同様にして、約６．５ｎｍのＦｅ粒子を含むＦｅ粒子粉末も作製し、これを用いて試料２の磁心を作製した。 It should be noted that Fe containing approximately 6.5 nm Fe particles was prepared in the same manner as in the preparation of the magnetic core of Sample 1, except that the mixing ratio of Fe (CO) 5 and surfactant (oleylamine) and the thermal decomposition conditions were changed. A particle powder was also produced, and a magnetic core of Sample 2 was produced using this.
試料１の磁心を粉砕して得たＦｅ粒子粉末を透過型電子顕微鏡にて観察し、得られたＴＥＭ像より任意に選択されるＦｅ粒子２００個の平均値から、試料１の磁心におけるＦｅ粒子の粒径を求めた。その結果、試料１の磁心におけるＦｅ粒子の粒径は、４．０ｎｍであり、上記磁心を作製する前段階のＦｅ粒子粉末の観察および分析結果とよく一致していた。また、同様の測定の結果、試料２の磁心におけるＦｅ粒子の粒径は、６．５ｎｍであった。 The Fe particle powder obtained by pulverizing the magnetic core of sample 1 is observed with a transmission electron microscope, and from the average value of 200 Fe particles arbitrarily selected from the obtained TEM image, Fe particles in the magnetic core of sample 1 are obtained. The particle size of was determined. As a result, the particle size of Fe particles in the magnetic core of Sample 1 was 4.0 nm, which was in good agreement with the observation and analysis results of the Fe particle powder in the previous stage for producing the magnetic core. As a result of the same measurement, the particle size of Fe particles in the magnetic core of Sample 2 was 6.5 nm.
一方、Ｆｅアセチルアセトナートとオレイルアミンとを混合し、Ｆｅアセチルアセトナートを熱分解することにより、粒径４．０ｎｍのＦｅ３Ｏ４粒子粉末を得た。得られたＦｅ３Ｏ４粒子粉末を、上記と同じ大きさのリング形状に形成された樹脂ケースに封入することにより、試料１Ｃの磁心を得た。 On the other hand, Fe acetylacetonate and oleylamine were mixed, and Fe acetylacetonate was thermally decomposed to obtain Fe 3 O 4 particle powder having a particle size of 4.0 nm. The obtained Fe 3 O 4 particle powder was enclosed in a resin case formed in a ring shape having the same size as described above, thereby obtaining a magnetic core of Sample 1C.
試料１の磁心を粉砕して得たＦｅ粒子粉末、試料１Ｃの磁心に用いたＦｅ３Ｏ４粒子粉末について、振動試料型磁力計（ＶＳＭ）を用いて飽和磁化の値を測定した。その結果、Ｆｅ粒子粉末におけるＦｅ粒子の飽和磁化は、１０９．４ｅｍｕ／ｇ、Ｆｅ３Ｏ４粒子粉末におけるＦｅ３Ｏ４粒子の飽和磁化は、５０．０ｅｍｕ／ｇであった。なお、Ｆｅの飽和磁化１０９．４ｅｍｕ／ｇと磁心の体積および重量から算出される試料１の磁心の飽和磁束密度は０．２７Ｔであり、０．２０Ｔ以上であった。 With respect to the Fe particle powder obtained by pulverizing the magnetic core of Sample 1 and the Fe 3 O 4 particle powder used for the magnetic core of Sample 1C, the saturation magnetization value was measured using a vibrating sample magnetometer (VSM). As a result, the saturation magnetization of the Fe particles in Fe particles, the saturation magnetization of 109.4emu / g, Fe 3 O 4 Fe in particles 3 O 4 particles was 50.0emu / g. Note that the saturation magnetic flux density of the magnetic core of Sample 1 calculated from the saturation magnetization of 109.4 emu / g of Fe and the volume and weight of the magnetic core was 0.27 T, which was 0.20 T or more.
また、試料１の磁心について、上述した方法によりＦｅ粒子の体積分率を測定したところ、３１％であった。 Further, regarding the magnetic core of Sample 1, the volume fraction of Fe particles was measured by the method described above, and it was 31%.
試料１の磁心について、ＢＨアナライザを用いて交流磁気特性（最大磁束密度Ｂｍａｘ＝５０ｍＴ、周波数＝１、１０、１００ｋＨｚ）を測定した。損失の周波数依存性を図３に示す。図３に示されるように、試料１の磁心は、いずれの周波数であっても交流磁化曲線の周波数依存性が小さいことから、渦電流損失はほぼ生じていないことがわかる。また、試料１の磁心は、１００ｋＨｚの周波数においてもヒステリシスが観測されず、コアロスは測定限界以下であった。なお、図３には示されていないが、粒径６．５ｎｍのＦｅ粉末粒子を用いて同様に作製した磁心では、強磁性由来のヒステリシスが観測され、コアロスは１００ｋＨｚで１４８８ｋＷ／ｍ３であった。上記結果から、試料１の磁心は、損失が非常に小さいことが確認された。また、磁性粒子であるＦｅ粒子の粒径を６．５ｎｍ未満とすることにより、損失低減に有利な磁心が得られることが確認された。 The magnetic core of Sample 1 was measured for AC magnetic characteristics (maximum magnetic flux density B max = 50 mT, frequency = 1, 10, 100 kHz) using a BH analyzer. The frequency dependence of the loss is shown in FIG. As shown in FIG. 3, the magnetic core of the sample 1 has almost no eddy current loss since the frequency dependence of the AC magnetization curve is small at any frequency. Further, no hysteresis was observed in the magnetic core of Sample 1 even at a frequency of 100 kHz, and the core loss was below the measurement limit. Although not shown in FIG. 3, in a magnetic core similarly manufactured using Fe powder particles having a particle diameter of 6.5 nm, a hysteresis derived from ferromagnetism was observed, and the core loss was 1488 kW / m 3 at 100 kHz. It was. From the above results, it was confirmed that the loss of the magnetic core of Sample 1 was very small. Moreover, it was confirmed that the magnetic core advantageous for loss reduction can be obtained by making the particle size of Fe particles as magnetic particles less than 6.5 nm.
試料１の磁心、試料１Ｃの磁心について、直流ＢＨトレーサーを用いて直流磁気特性を測定した。その結果を、図４に示す。図４に示されるように、Ｆｅ粒子より構成される試料１の磁心は、Ｆｅ３Ｏ４粒子より構成される試料１Ｃの磁心に比べ、比透磁率（図４における直線の傾き）が向上していることがわかる。これは、以下によるものと考えられる。すなわち、試料１の磁心では、加圧成形により、飽和磁化の高い磁性粒子としてのＦｅ粒子の体積分率が２０％以上とされている。つまり、試料１の磁心では、飽和磁化の高い磁性粒子が高密度で存在している。そのため、高飽和磁化の磁性粒子の粒子間距離が短くなる。そのため、試料１の磁心は、有効な磁場として、外部磁場に加えて、隣り合う磁性粒子から発生する双極子磁場も加わる。その結果、試料１の磁心は、磁心全体としての比透磁率を向上させることができたものと考えられる。なお、試料１の磁心の比透磁率は８．７５であり、６以上であった。一方、試料１Ｃの磁心は、樹脂ケースにＦｅ３Ｏ４粒子が粉末状態で封入されており、磁性粒子が低密度で存在している。そのため、試料１Ｃの磁心は、上記メカニズムによる比透磁率の向上が見られなかったものと考えられる。 The DC magnetic characteristics of the magnetic core of sample 1 and the magnetic core of sample 1C were measured using a DC BH tracer. The result is shown in FIG. As shown in FIG. 4, the magnetic permeability of sample 1 composed of Fe particles is improved in relative permeability (the slope of the straight line in FIG. 4) compared to the magnetic core of sample 1C composed of Fe 3 O 4 particles. You can see that This is considered to be due to the following. That is, in the magnetic core of the sample 1, the volume fraction of Fe particles as magnetic particles having high saturation magnetization is set to 20% or more by pressure molding. That is, in the magnetic core of the sample 1, magnetic particles with high saturation magnetization are present at high density. For this reason, the inter-particle distance of magnetic particles with high saturation magnetization is shortened. Therefore, in addition to the external magnetic field, the magnetic core of the sample 1 also receives a dipole magnetic field generated from adjacent magnetic particles as an effective magnetic field. As a result, it is considered that the magnetic core of the sample 1 was able to improve the relative permeability as the whole magnetic core. Note that the relative permeability of the magnetic core of Sample 1 was 8.75, which was 6 or more. On the other hand, in the magnetic core of the sample 1C, Fe 3 O 4 particles are encapsulated in a powder state in a resin case, and magnetic particles are present at a low density. Therefore, it is considered that the magnetic permeability of sample 1C was not improved in the relative magnetic permeability due to the above mechanism.
また、試料１の磁心について、以下の２条件での温度と磁化との関係を求め、超常磁性を有するか否かの確認を行った。条件１は、５Ｏｅの磁場をかけた状態で温度５Ｋとし、その後、５Ｏｅの磁場をかけた状態で温度５Ｋから温度を上昇させ、磁化測定を実施するというものである。条件２は、５Ｏｅの磁場をかけずに温度５Ｋとし、その後、５Ｏｅの磁場をかけた状態で温度５Ｋから温度を上昇させ、磁化測定を実施するというものである。その結果を、図５に示す。図５に示されるように、試料１の磁心は、１５０Ｋにおいて超常磁性転移温度が観測され、室温では超常磁性的な振る舞いを示していることが確認された。また、図５に示される磁化の温度依存性から推定される超常磁性転移温度の変化から、Ｆｅ粒子同士が焼結していないことも併せて確認された。 Further, regarding the magnetic core of the sample 1, the relationship between temperature and magnetization under the following two conditions was obtained, and it was confirmed whether or not it had superparamagnetism. Condition 1 is that the temperature is set to 5 K in a state where a magnetic field of 5 Oe is applied, and then the temperature is increased from the temperature 5 K in a state where a magnetic field of 5 Oe is applied, and magnetization measurement is performed. Condition 2 is that the temperature is set to 5 K without applying a magnetic field of 5 Oe, and thereafter the temperature is increased from the temperature 5 K in a state where the magnetic field of 5 Oe is applied, and the magnetization measurement is performed. The result is shown in FIG. As shown in FIG. 5, the magnetic core of Sample 1 has a superparamagnetic transition temperature observed at 150 K, and it has been confirmed that the magnetic core exhibits superparamagnetic behavior at room temperature. It was also confirmed that Fe particles were not sintered from the change in superparamagnetic transition temperature estimated from the temperature dependence of magnetization shown in FIG.
本発明は、上記各実施形態に限定されるものではなく、その要旨を逸脱しない範囲において種々の変更が可能である。また、各実施形態に示される各構成は、任意に組み合わせることができる。 The present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Moreover, each structure shown by each embodiment can be combined arbitrarily.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016033244A JP6748446B2 (en) | 2016-02-24 | 2016-02-24 | Magnetic core and coil member |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016033244A JP6748446B2 (en) | 2016-02-24 | 2016-02-24 | Magnetic core and coil member |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2017152529A true JP2017152529A (en) | 2017-08-31 |
| JP6748446B2 JP6748446B2 (en) | 2020-09-02 |
Family
ID=59742100
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2016033244A Active JP6748446B2 (en) | 2016-02-24 | 2016-02-24 | Magnetic core and coil member |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6748446B2 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04188705A (en) * | 1990-11-22 | 1992-07-07 | Natl Res Inst For Metals | Lattice arrangement structure of magnetic fine particle |
| JP2013243185A (en) * | 2012-05-18 | 2013-12-05 | National Institute Of Advanced Industrial & Technology | Method for producing nano crystal magnetic body |
| JP2014131054A (en) * | 2011-08-31 | 2014-07-10 | Toshiba Corp | Magnetic material |
| JP2014207288A (en) * | 2013-04-11 | 2014-10-30 | 株式会社デンソー | Soft magnetic material for magnetic core, powder-compact magnetic core and coil member |
| US20150294775A1 (en) * | 2014-04-14 | 2015-10-15 | Toyota Motor Engineering & Manufacturing North America, Inc. | Core shell superparamagnetic iron cobalt alloy nanoparticles with functional metal silicate core shell interface and a magnetic core containing the nanoparticles |
-
2016
- 2016-02-24 JP JP2016033244A patent/JP6748446B2/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04188705A (en) * | 1990-11-22 | 1992-07-07 | Natl Res Inst For Metals | Lattice arrangement structure of magnetic fine particle |
| JP2014131054A (en) * | 2011-08-31 | 2014-07-10 | Toshiba Corp | Magnetic material |
| JP2013243185A (en) * | 2012-05-18 | 2013-12-05 | National Institute Of Advanced Industrial & Technology | Method for producing nano crystal magnetic body |
| JP2014207288A (en) * | 2013-04-11 | 2014-10-30 | 株式会社デンソー | Soft magnetic material for magnetic core, powder-compact magnetic core and coil member |
| US20150294775A1 (en) * | 2014-04-14 | 2015-10-15 | Toyota Motor Engineering & Manufacturing North America, Inc. | Core shell superparamagnetic iron cobalt alloy nanoparticles with functional metal silicate core shell interface and a magnetic core containing the nanoparticles |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6748446B2 (en) | 2020-09-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4457682B2 (en) | Powder magnetic core and manufacturing method thereof | |
| WO2012131872A1 (en) | Composite soft magnetic powder, method for producing same, and powder magnetic core using same | |
| JP6942379B2 (en) | Magnetic materials and their manufacturing methods | |
| JP6471260B2 (en) | Soft magnetic materials, dust cores using soft magnetic materials, reactors using dust cores | |
| JP2013051329A (en) | Magnetic material, method for manufacturing magnetic material, and inductor element using magnetic material | |
| CN107658090B (en) | Soft magnetic metal powder magnetic core and reactor provided with same | |
| JP2013106016A (en) | Alcoholic solution and sintered magnet | |
| US9607740B2 (en) | Hard-soft magnetic MnBi/SiO2/FeCo nanoparticles | |
| CN110853910B (en) | Preparation method of high-permeability low-loss soft magnetic composite material and magnetic ring thereof | |
| JP5732945B2 (en) | Fe-Ni alloy powder | |
| JP5439888B2 (en) | Composite magnetic material and method for producing the same | |
| JP6461828B2 (en) | Method for producing magnetic particles | |
| JP5168637B2 (en) | Metal magnetic fine particles and production method thereof, dust core | |
| US9941039B2 (en) | Soft magnetic member, reactor, powder for dust core, and method of producing dust core | |
| JP2005213621A (en) | Soft magnetic material and powder magnetic core | |
| JP5150535B2 (en) | Powder magnetic core and manufacturing method thereof | |
| TW201346946A (en) | Powder mixture for dust cores | |
| JP6578266B2 (en) | Soft magnetic material, dust core using soft magnetic material, and method for manufacturing dust core | |
| US9997289B2 (en) | Magnetic material and device | |
| JP6748446B2 (en) | Magnetic core and coil member | |
| JP2008143720A (en) | Magnetite-iron composite powder, its manufacturing method and dust core | |
| JP6742674B2 (en) | Metal powder | |
| JP2011211026A (en) | Composite magnetic material | |
| JP2008297622A (en) | Soft magnetic material, dust core, method for manufacturing soft magnetic material and method for manufacturing dust core | |
| JP2009272615A (en) | Dust core, and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A80 | Written request to apply exceptions to lack of novelty of invention |
Free format text: JAPANESE INTERMEDIATE CODE: A80 Effective date: 20160322 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20190118 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20190625 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20190820 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20190820 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20200121 |
|
| 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: 20200714 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20200807 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6748446 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |