JP7285496B2 - Flat iron particles and method for producing the same - Google Patents
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本発明は、扁平状鉄粒子及びその製造方法に関する。 TECHNICAL FIELD The present invention relates to flattened iron particles and a method for producing the same.
従来、モータのコアやリアクトル等の電磁気応用製品に用いられる軟磁性材料等の金属材料が知られている。金属材料においては、その機能の向上のため、集合組織（ｔｅｘｔｕｒｅ又はｃｒｙｓｔａｌ ｔｅｘｔｕｒｅとも呼称される）の制御が行われる。例えば、特許文献１には、金属粒子を含む金属粉を粉砕加工等のメカノケミカル処理することにより、結晶方位を所定の方向に制御した集合組織を有する扁平金属粒子の製造方法が開示されている。 2. Description of the Related Art Conventionally, metal materials such as soft magnetic materials used for electromagnetic application products such as motor cores and reactors are known. In metal materials, the texture (also called texture or crystal texture) is controlled in order to improve their functions. For example, Patent Document 1 discloses a method for producing flat metal particles having a texture in which the crystal orientation is controlled in a predetermined direction by subjecting metal powder containing metal particles to mechanochemical treatment such as pulverization. .
しかしながら、従来の技術で作製した金属材料は、結晶方位の制御のために強加工を受けているため、材料内部に格子欠陥（加工歪み等）が存在する場合がある。この格子欠陥は、保磁力を向上させ、かつ圧粉成形を困難にすることがある。そのため、格子欠陥を取り除くために、粉砕加工等のメカノケミカル処理を施した金属材料に熱処理を施さなければならないが、熱処理によって再結晶が発生してしまい、結晶方位を制御した集合組織が崩れてしまうという問題がある。 However, since the metal material produced by the conventional technique is subjected to severe working for controlling the crystal orientation, there are cases where lattice defects (work strain, etc.) are present inside the material. This lattice defect can improve coercivity and make compaction difficult. Therefore, in order to remove lattice defects, it is necessary to apply heat treatment to metal materials that have undergone mechanochemical treatment such as pulverization. There is a problem of storage.
本発明は、結晶配向性が高く、かつ局所方位差が小さい、安定した集合組織を有する、磁気特性に優れた扁平状鉄粒子及びその製造方法を提供する。 The present invention provides flat iron particles with high crystal orientation, small local misorientation, stable texture, and excellent magnetic properties, and a method for producing the same.
本発明の一の態様である扁平状鉄粒子は、Ｘ線回折において（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａが８以上であり、かつ、結晶方位解析において局所方位差が１度以下の領域が２０％以上である集合組織を有する。 The flat iron particles, which are one aspect of the present invention, have a peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane in X-ray diffraction of 8 or more, and , has a texture in which 20% or more of the region has a local misorientation of 1 degree or less in the crystal orientation analysis.
上記扁平状鉄粒子によれば、結晶配向性が高く、かつ局所方位差が小さい集合組織を有する。すなわち、結晶方位を所定の方向に制御し、かつ格子欠陥（例えば粉砕による加工歪み等）を抑制した集合組織を有する。そのため、安定した集合組織となり、優れた磁気特性を有するものとなる。 The flattened iron particles have a texture with high crystal orientation and a small local misorientation. That is, it has a texture in which the crystal orientation is controlled in a predetermined direction and lattice defects (for example, processing distortion due to pulverization) are suppressed. Therefore, it becomes a stable texture and has excellent magnetic properties.
これにより、上記扁平状鉄粒子を用いた成形品は、ヒステリシス損や渦電流損が小さく、磁束密度が高いため、優れた磁気特性を有する。よって、変圧器、電動機、発電機等の鉄心（コア）やリアクトル等の電磁気応用製品への適用が非常に有効であり、これらの電磁気応用製品の機能性を向上させるのに寄与する。 As a result, a molded article using the flattened iron particles has excellent magnetic properties due to small hysteresis loss and eddy current loss and high magnetic flux density. Therefore, application to electromagnetic application products such as cores and reactors of transformers, motors, generators, etc. is very effective, and contributes to improving the functionality of these electromagnetic application products.
上記扁平状鉄粒子において、Ｘ線回折においてピーク強度比Ｂ／Ａが９以上であってもよい。 The flat iron particles may have a peak intensity ratio B/A of 9 or more in X-ray diffraction.
また、扁平状鉄粒子の厚さが０．１μｍ以上２０μｍ以下であってもよい。 Moreover, the thickness of the flat iron particles may be 0.1 μm or more and 20 μm or less.
また、扁平状鉄粒子の厚さをｔ、扁平状鉄粒子の厚さ方向と直交する方向における径をｄとした場合、扁平状鉄粒子のアスペクト比ｄ／ｔが１０以上であってもよい。 Further, the aspect ratio d/t of the flat iron particles may be 10 or more, where t is the thickness of the flat iron particles, and d is the diameter of the flat iron particles in the direction orthogonal to the thickness direction. .
本発明の他の態様である扁平状鉄粒子の製造方法は、潤滑剤を用いて鉄粒子を粉砕する粉砕工程と、扁平状に粉砕した鉄粒子を焼鈍する焼鈍工程と、を有する。 A method for producing flat iron particles, which is another aspect of the present invention, includes a pulverization step of pulverizing iron particles using a lubricant, and an annealing step of annealing the flat pulverized iron particles.
上記扁平状鉄粒子の製造方法によれば、粉砕工程により、結晶配向性が高い集合組織を有する扁平状の鉄粒子が得られる。また、粉砕工程において潤滑剤を用いて鉄粒子を粉砕しているため、焼鈍工程において鉄粒子を焼鈍（熱処理）しても、高い結晶配向性は保持され、かつ格子欠陥（粉砕による加工歪み等）を十分に取り除くことができる。これにより、結晶配向性が高く、かつ局所方位差が小さい、安定した集合組織を有する、磁気特性に優れた扁平状鉄粒子が得られる。 According to the method for producing flat iron particles, the pulverization step provides flat iron particles having a texture with high crystal orientation. In addition, since the iron particles are pulverized using a lubricant in the pulverization process, even if the iron particles are annealed (heat treated) in the annealing process, high crystal orientation is maintained and lattice defects (processing strain due to pulverization, etc.) ) can be sufficiently removed. As a result, flat iron particles with high crystal orientation, small local misorientation, stable texture, and excellent magnetic properties can be obtained.
上記扁平状鉄粒子の製造方法において、潤滑剤は、層状化合物からなる潤滑物質を含んでいてもよい。 In the method for producing flat iron particles, the lubricant may contain a lubricating substance comprising a layered compound.
また、層状化合物からなる潤滑物質は、窒化ホウ素及び二硫化モリブデンのうち少なくとも一方を含んでいてもよい。 Also, the lubricating substance made of a layered compound may contain at least one of boron nitride and molybdenum disulfide.
また、焼鈍工程では、扁平状に粉砕した鉄粒子を鉄粒子の回復・再結晶温度以上の温度で焼鈍してもよい。 Further, in the annealing step, the flat-crushed iron particles may be annealed at a temperature equal to or higher than the recovery/recrystallization temperature of the iron particles.
また、扁平状鉄粒子は、Ｘ線回折において（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａが８以上であり、かつ、結晶方位解析において局所方位差が度以下の領域が２０％以上である集合組織を有していてもよい。 In addition, the flat iron particles have a peak intensity ratio B/A of 8 or more between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane in X-ray diffraction, and It may have a texture in which 20% or more of the regions have an orientation difference of 10 degrees or less.
また、扁平状鉄粒子は、Ｘ線回折においてピーク強度比Ｂ／Ａが９以上であってもよい。 Further, the flat iron particles may have a peak intensity ratio B/A of 9 or more in X-ray diffraction.
また、扁平状鉄粒子の厚さが０．１μｍ以上２０μｍ以下であってもよい。 Moreover, the thickness of the flat iron particles may be 0.1 μm or more and 20 μm or less.
また、扁平状鉄粒子の厚さをｔ、扁平状鉄粒子の厚さ方向と直交する方向における径をｄとした場合、扁平状鉄粒子のアスペクト比ｄ／ｔが１０以上であってもよい。 Further, the aspect ratio d/t of the flat iron particles may be 10 or more, where t is the thickness of the flat iron particles, and d is the diameter of the flat iron particles in the direction orthogonal to the thickness direction. .
以下、本発明の実施形態について説明する。 Embodiments of the present invention will be described below.
［扁平状鉄粒子］
まず、扁平状鉄粒子について説明する。
[Flat iron particles]
First, the flat iron particles will be described.
扁平状鉄粒子は、集合組織を有する。集合組織を有する扁平状鉄粒子の組成は特に限定されない。扁平状鉄粒子の組成としては、純鉄であってもよいし、鉄合金であってもよい。鉄合金としては、例えば、鉄コバルト合金、鉄コバルトバナジウム合金、鉄バナジウム合金、クロム鉄合金、鉄アルミシリコン合金、鉄シリコンクロム合金、ケイ素鋼等が挙げられる。 Flattened iron particles have a texture. The composition of the textured flattened iron particles is not particularly limited. The composition of the flat iron particles may be pure iron or an iron alloy. Examples of iron alloys include iron-cobalt alloys, iron-cobalt-vanadium alloys, iron-vanadium alloys, chromium-iron alloys, iron-aluminum-silicon alloys, iron-silicon-chromium alloys, and silicon steel.
扁平状鉄粒子は、扁平面を有する。扁平面は、扁平化した粒子における厚さ方向に直交する面を示す。扁平面は、平坦であることが好ましい。また、扁平面は、曲面であってもよい。このような扁平面は、例えば、鉄粒子を粉砕処理等することにより形成される面である。 Flattened iron particles have flattened surfaces. A flat plane indicates a plane perpendicular to the thickness direction in a flattened particle. The flat surface is preferably flat. Also, the flat surface may be a curved surface. Such a flat surface is, for example, a surface formed by crushing iron particles.
扁平状鉄粒子は、Ｘ線回折において（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａが８以上である。すなわち、Ｘ線回折によって得られるＸ線回折パターンにおいて、（１１０）面の回折ピークの強度（ピーク強度Ａ）と（００２）面の回折ピークの強度（ピーク強度Ｂ）との比（ピーク強度比Ｂ／Ａ）が８以上である。また、Ｘ線回折においてピーク強度比Ｂ／Ａが９以上であることが好ましい。 The flat iron particles have a peak intensity ratio B/A of the peak intensity A of the (110) plane and the peak intensity B of the (002) plane of 8 or more in X-ray diffraction. That is, in the X-ray diffraction pattern obtained by X-ray diffraction, the ratio (peak intensity ratio B/A) is 8 or more. Also, the peak intensity ratio B/A in X-ray diffraction is preferably 9 or more.
なお、Ｘ線回折は、例えば、粉末Ｘ線回折装置等を用いて行うことができる。また、所定の結晶面の回折ピークの強度とは、Ｘ線回折パターンのベースラインからのピークの高さとして定義される。また、ピーク強度比が高いほど、扁平面内において磁化容易軸を含まない（１１１）面を減少させ、磁化容易軸を含む（００２）面を増加させ、結晶方位を所定の方向に制御できていると言える。 X-ray diffraction can be performed using, for example, a powder X-ray diffractometer. Also, the intensity of the diffraction peak of a given crystal plane is defined as the height of the peak from the baseline of the X-ray diffraction pattern. In addition, the higher the peak intensity ratio, the smaller the (111) plane that does not include the easy axis of magnetization in the flat plane, the larger the (002) plane that includes the easy axis of magnetization, and the more the crystal orientation can be controlled in a predetermined direction. It can be said that there are
扁平状鉄粒子は、結晶方位解析において局所方位差が１度以下の領域が２０％以上である。すなわち、結晶方位解析によって局所方位差を測定した領域において、局所方位差が１度以下の領域が全体の領域に対して２０％以上を占める。 In the crystal orientation analysis, 20% or more of the flat iron particles have a local misorientation of 1 degree or less. That is, in the region where the local misorientation is measured by the crystal orientation analysis, the region where the local misorientation is 1 degree or less occupies 20% or more of the entire region.
なお、結晶方位解析は、例えば、ＥＢＳＤ（Ｅｌｅｃｔｒｏｎ Ｂａｃｋ Ｓｃａｔｔｅｒ Ｄｉｆｆｒａｃｔｉｏｎ）検出器付き電子顕微鏡等を用いて行うことができる。局所方位差は、局所的な結晶方位の変化である。局所方位差は、例えば、ＥＢＳＤ検出器付き電子顕微鏡を用いて、扁平状鉄粒子のＫＡＭ（Ｋｅｒｎｅｌ Ａｖｅｒａｇｅ Ｍｉｓｏｒｉｅｎｔａｔｉｏｎ）マップを作成することによって得られる。すなわち、このＫＡＭマップを規定する測定値が、測定点とその隣接する全ての測定点間の方位の平均差であり、これが局所方位差である。 The crystal orientation analysis can be performed using, for example, an electron microscope with an EBSD (Electron Back Scatter Diffraction) detector. Local misorientation is a change in local crystal orientation. The local misorientation is obtained, for example, by using an electron microscope with an EBSD detector to create a KAM (Kernel Average Misorientation) map of flattened iron particles. That is, the measurement that defines this KAM map is the average difference in orientation between a measurement point and all its neighboring measurement points, which is the local orientation difference.
扁平状鉄粒子は、Ｘ線回折においてピーク強度比Ｂ／Ａが８以上であり、結晶方位解析において局所方位差が１度以下の領域が２０％以上であることにより、結晶配向性が高く、かつ局所方位差が小さい集合組織となる。すなわち、結晶方位を所定の方向に制御し、かつ格子欠陥（加工歪み等）を抑制し、保磁力を低下させた集合組織となる。そのため、安定した集合組織となり、優れた磁気特性を有するものとなる。 The flat iron particles have a peak intensity ratio B/A of 8 or more in X-ray diffraction, and a region with a local misorientation of 1 degree or less in crystal orientation analysis is 20% or more, so that the crystal orientation is high. In addition, a texture with a small local orientation difference is obtained. That is, the crystal orientation is controlled in a predetermined direction, lattice defects (such as working strain) are suppressed, and the coercive force is lowered. Therefore, it becomes a stable texture and has excellent magnetic properties.
これにより、扁平状鉄粒子を用いた成形品は、ヒステリシス損や渦電流損が小さく、磁束密度が高いため、優れた磁気特性を有する。よって、変圧器、電動機、発電機等の鉄心（コア）やリアクトル等の電磁気応用製品への適用が非常に有効であり、これらの電磁気応用製品の機能性を向上させるのに寄与する。 As a result, the molded product using the flattened iron particles has excellent magnetic properties due to its small hysteresis loss and eddy current loss and its high magnetic flux density. Therefore, application to electromagnetic application products such as cores and reactors of transformers, motors, generators, etc. is very effective, and contributes to improving the functionality of these electromagnetic application products.
扁平状鉄粒子の平均粒径は、０．２μｍ以上２０００μｍ以下であることが好ましい。なお、粒径とは、扁平状鉄粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）である。 The average particle diameter of the flat iron particles is preferably 0.2 μm or more and 2000 μm or less. The particle size is the diameter (the length of the widest part) in the direction orthogonal to the thickness direction of the flattened iron particles.
扁平状鉄粒子の厚さ（扁平面に直交する方向における扁平状鉄粒子の幅長）は、０．１μｍ以上２０μｍ以下であってもよい。この場合には、例えば成形型に扁平状鉄粒子を充填して成形品を作る際に、成形型内で粒子配向が生じ、粒子形状に関連付けられている磁化容易軸の向きを、圧縮軸やその垂直方向に配向できる。また、成形型への扁平状鉄粒子の充填率を向上させることができる。これにより、成形品の磁気特性を向上させることができる。 The thickness of the flat iron particles (the width of the flat iron particles in the direction perpendicular to the flat surface) may be 0.1 μm or more and 20 μm or less. In this case, for example, when flattened iron particles are filled into a mold to produce a molded product, particle orientation occurs in the mold, and the direction of the axis of easy magnetization associated with the particle shape is changed to the compression axis or It can be oriented in its vertical direction. In addition, it is possible to improve the filling rate of the flat iron particles in the mold. Thereby, the magnetic properties of the molded product can be improved.
扁平状鉄粒子の厚さをｔ、扁平状鉄粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）をｄとした場合、扁平状鉄粒子のアスペクト比ｄ／ｔは、１０以上であってもよい。この場合には、成形型内で粒子配向が生じ、粒子形状に関連付けられている磁化容易軸の向きを、圧縮軸やその垂直方向に配向できる。また、扁平状鉄粒子を用いた成形品のヒステリシス損の低減等、磁気特性を向上させたりすることができる。 When the thickness of the flat iron particles is t, and the diameter (the length of the widest part) of the flat iron particles in the direction orthogonal to the thickness direction is d, the aspect ratio of the flat iron particles is d/t. may be 10 or more. In this case, grain orientation occurs within the mold, and the easy axis of magnetization associated with the grain shape can be oriented along the compression axis or perpendicular thereto. In addition, it is possible to improve magnetic properties such as reduction of hysteresis loss of molded products using flat iron particles.
［扁平状鉄粒子の製造方法］
次に、扁平状鉄粒子の製造方法について説明する。
[Method for producing flat iron particles]
Next, a method for producing flat iron particles will be described.
扁平状鉄粒子の製造方法は、潤滑剤を用いて鉄粒子を粉砕する粉砕工程と、扁平状に粉砕した鉄粒子を焼鈍する焼鈍工程と、を有する。 A method for producing flat iron particles includes a pulverization step of pulverizing iron particles using a lubricant, and an annealing step of annealing the flat pulverized iron particles.
粉砕工程では、潤滑剤を用いて鉄粒子を粉砕する。これにより、結晶配向性が高い集合組織を有する扁平状の鉄粒子が得られる。すなわち、扁平面内において磁化容易軸を含まない（１１１）面を減少させ、磁化容易軸を含む（００２）面を増加させ、結晶方位を所定の方向に制御した集合組織を有する扁平状の鉄粒子が得られる。 In the pulverization step, the iron particles are pulverized using a lubricant. As a result, flat iron particles having a texture with high crystal orientation can be obtained. That is, flat iron having a texture in which the (111) plane that does not contain the easy axis of magnetization is reduced in the flat plane, the (002) plane that contains the easy axis of magnetization is increased, and the crystal orientation is controlled in a predetermined direction. Particles are obtained.
粉砕工程において、鉄粒子の粉砕処理としては、例えば、粒子状の材料に圧縮力や摩擦力等の機械的エネルギーを加えることによって、材料同士の力学的・化学的相互作用を誘起すると共に、粒子形状を変形させるメカノケミカル処理等を用いることができる。メカノケミカル処理としては、特に限定されるものではなく、例えば機械的粉砕装置等を用いることができる。例えば、ビーズミル、遊星式、転動式、振動式等のボールミル、ロッキングミル、タワーミル、メカノフュージョン、ジェットミル、ハイブリダイザー、ヘンシェルミキサー、ホモミキサー等が挙げられる。 In the pulverization process, the iron particles are pulverized, for example, by applying mechanical energy such as compressive force and frictional force to the particulate material to induce mechanical and chemical interactions between the materials, and A mechanochemical treatment or the like for deforming the shape can be used. The mechanochemical treatment is not particularly limited, and for example, a mechanical pulverizer or the like can be used. Examples include bead mills, planetary, tumbling, vibrating ball mills, rocking mills, tower mills, mechanofusion, jet mills, hybridizers, Henschel mixers, homomixers, and the like.
粉砕処理の際に用いられるミル等の粉砕処理容器については、その材質は限定されるものではないが、例えば金属や金属酸化物製のものであることが好ましい。これは、粉砕処理を行う際に、上記のような材料であると、鉄粒子に十分な機械的エネルギーを付与することができるためである。 The material of the pulverizing container such as a mill used for the pulverizing treatment is not particularly limited, but is preferably made of metal or metal oxide, for example. This is because the material described above can impart sufficient mechanical energy to the iron particles during the pulverization process.
粉砕処理を行う装置として、例えば、メカノフュージョン（ホソカワミクロン社製）等のような球状媒体を使用しない装置を選択した場合には、球状媒体を入れる必要はなく、その球状媒体の導入量を０とすることができる。 If a device that does not use spherical media, such as Mechanofusion (manufactured by Hosokawa Micron Corporation), is selected as the pulverization device, there is no need to add spherical media, and the amount of spherical media introduced is set to zero. can do.
球状媒体を使用する装置を選択した場合、球状媒体の材質については限定されるものではなく、粉砕処理容器の大きさや材質により選択することができる。なお、球状媒体としては金属や金属酸化物製のものを用いた場合は、粉砕処理を行う際、粉末材料に十分な機械的エネルギーを付与することができる。また、粉砕処理で用いられる球状媒体のサイズについては特に限定されるものではなく、粉砕処理容器のサイズ等に応じて選択することができる。 When a device using spherical media is selected, the material of the spherical media is not limited and can be selected according to the size and material of the pulverization processing container. When a spherical medium made of metal or metal oxide is used as the spherical medium, sufficient mechanical energy can be imparted to the powder material during the pulverization process. Also, the size of the spherical media used in the pulverization process is not particularly limited, and can be selected according to the size of the pulverization processing container and the like.
粉砕工程において、鉄粒子の粉砕処理の処理時間は制限されることが好ましい。粉砕処理の処理時間が長すぎると、アスペクト比が小さくなりすぎたり、合金化したりするおそれがある。粉砕処理の処理時間は、粉砕処理の装置（例えば、ボールミル装置）及びその条件（ボールの大きさ及び質量、容器の回転数）により適宜設定することができる。 In the pulverization step, it is preferable that the treatment time for pulverizing the iron particles is limited. If the treatment time of the pulverization treatment is too long, the aspect ratio may become too small, or alloying may occur. The processing time of the pulverization treatment can be appropriately set depending on the pulverization device (for example, ball mill device) and its conditions (size and mass of balls, number of revolutions of container).
粉砕工程において、鉄粒子の粉砕処理に潤滑剤を用いる。潤滑剤は、固体状であってもよいし、液体状であってもよい。潤滑剤とは、潤滑機能を発揮する潤滑物質を含むものである。ここで、潤滑物質を含む潤滑剤とは、予め潤滑物質が含まれている潤滑剤だけでなく、例えば粉砕による圧力を受けたときにその受圧面に潤滑物質が形成されるような潤滑剤も含まれる。また、潤滑機能とは、粉砕処理される鉄粒子と粉砕処理を行う物体（例えば、ボール等の球状媒体）との間の摩擦係数を低下させることをいう。鉄粒子の粉砕処理に潤滑剤を用いることにより、粉砕処理による鉄粒子の集合組織化を促進させることができる。 In the pulverization process, a lubricant is used for pulverizing the iron particles. The lubricant may be solid or liquid. A lubricant includes a lubricating substance that exhibits a lubricating function. Here, the lubricant containing a lubricating substance means not only a lubricant that contains a lubricating substance in advance, but also a lubricant that forms a lubricating substance on the pressure receiving surface when subjected to pressure due to pulverization, for example. included. Also, the lubricating function means reducing the coefficient of friction between the iron particles to be pulverized and the object (for example, spherical medium such as a ball) to be pulverized. By using a lubricant in the pulverization process of the iron particles, it is possible to promote the formation of a texture of the iron particles by the pulverization process.
潤滑剤は、層状化合物からなる潤滑物質を含んでいてもよい。層状化合物からなる潤滑物質としては、例えば、六方晶窒化ホウ素、二硫化モリブデン、マイカ、タルク、黒鉛、フッ化黒鉛等が挙げられる。層状化合物からなる潤滑物質を含む潤滑剤には、例えば粉砕による圧力を受けたときにその受圧面に二硫化モリブデンが形成されるモリブデンジチオカーバメート（ｍｏｌｙｂｄｅｎｕｍ ｄｉｔｈｉｏｃａｒｂａｍａｔｅ）も含まれる。なお、層状化合物とは、層状の結晶構造を有する化合物である。 Lubricants may include lubricating substances comprising layered compounds. Lubricating substances composed of layered compounds include, for example, hexagonal boron nitride, molybdenum disulfide, mica, talc, graphite, and graphite fluoride. Lubricants containing lubricating substances composed of layered compounds also include molybdenum dithiocarbamates, which form molybdenum disulfide on their pressure-receiving surfaces when subjected to pressure, for example by grinding. A layered compound is a compound having a layered crystal structure.
粉砕工程において、層状化合物からなる潤滑物質は、窒化ホウ素及び二硫化モリブデンのうち少なくとも一方を含んでいてもよい。この場合には、高温で焼鈍処理を施しても、強い結晶配向性を保持しつつ、格子欠陥（粉砕による加工歪み等）を十分に取り除くことができる。これにより、結晶配向性が高く、かつ局所方位差が小さく、非常に安定した集合組織を有する、磁気特性に優れた扁平状鉄粒子が得られる。 In the pulverization step, the lubricating substance made of the layered compound may contain at least one of boron nitride and molybdenum disulfide. In this case, lattice defects (processing distortion due to pulverization, etc.) can be sufficiently removed while maintaining strong crystal orientation even when annealing is performed at a high temperature. As a result, flattened iron particles with high crystal orientation, small local misorientation, very stable texture, and excellent magnetic properties can be obtained.
粉砕工程において、鉄粒子の粉砕処理には、上述した潤滑剤以外にも、アルコール等の助剤を用いてもよい。助剤は、粉砕処理による鉄粒子の集合組織化を促進させるものである。 In the pulverization process, an auxiliary agent such as alcohol may be used for the pulverization treatment of the iron particles in addition to the lubricant described above. Auxiliary agents promote the formation of a texture of iron particles by pulverization.
焼鈍工程では、粉砕工程において扁平状に粉砕した鉄粒子を焼鈍（熱処理）する。粉砕工程において潤滑剤を用いて鉄粒子を粉砕していることにより、鉄粒子を高温で焼鈍（熱処理）しても、高い結晶配向性は維持され、かつ粉砕による格子欠陥（加工歪み）を十分に取り除き、保磁力を低下させることができる。これにより、結晶配向性が高く、かつ局所方位差が小さい、安定した集合組織を有する、磁気特性に優れた扁平状鉄粒子が得られる。 In the annealing step, the flat iron particles crushed in the crushing step are annealed (heat treated). By pulverizing the iron particles using a lubricant in the pulverization process, even if the iron particles are annealed (heat treated) at a high temperature, high crystal orientation is maintained and lattice defects (processing strain) due to pulverization are sufficiently removed. can be removed to reduce the coercive force. As a result, flat iron particles with high crystal orientation, small local misorientation, stable texture, and excellent magnetic properties can be obtained.
焼鈍工程では、扁平状に粉砕した鉄粒子を鉄粒子の回復・再結晶温度以上の温度で焼鈍してもよい。この場合には、格子欠陥（粉砕による加工歪み等）を十分に取り除き、保磁力を低下させることができる。これにより、結晶配向性が高く、かつ局所方位差が小さい、非常に安定した集合組織を有する、磁気特性に優れた扁平状鉄粒子が得られる。なお、鉄粒子の回復・再結晶温度は、鉄粒子の組成（純鉄、各種鉄合金）、加工履歴等によって異なる。 In the annealing step, the flattened iron particles may be annealed at a temperature equal to or higher than the recovery/recrystallization temperature of the iron particles. In this case, lattice defects (processing distortion due to pulverization, etc.) can be sufficiently removed, and the coercive force can be reduced. As a result, it is possible to obtain flattened iron particles having a high crystal orientation, a small local misorientation, a very stable texture, and excellent magnetic properties. The recovery/recrystallization temperature of the iron particles varies depending on the composition of the iron particles (pure iron, various iron alloys), processing history, and the like.
上記製造方法によって得られる扁平状鉄粒子は、Ｘ線回折において（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａが８以上であり、かつ、結晶方位解析において局所方位差が度以下の領域が２０％以上である集合組織を有していてもよい。また、Ｘ線回折においてピーク強度比Ｂ／Ａが９以上であることが好ましい。この場合には、上記製造方法によって得られる扁平状鉄粒子は、結晶配向性が高く、かつ局所方位差が小さい、安定した集合組織を有する、磁気特性に優れたものとなる。 The flat iron particles obtained by the above production method have a peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane in X-ray diffraction of 8 or more, and It may have a texture in which 20% or more of the regions have local orientation differences of degrees or less in the orientation analysis. Also, the peak intensity ratio B/A in X-ray diffraction is preferably 9 or more. In this case, the flattened iron particles obtained by the above production method have a high crystal orientation, a small local misorientation, a stable texture, and excellent magnetic properties.
扁平状鉄粒子の厚さが０．１μｍ以上２０μｍ以下であってもよい。この場合には、粉砕工程における鉄粒子の粉砕に要する時間が長くなることを抑制できる。また、例えば成形型に扁平状鉄粒子を充填して成形品を作る際に、その成形型への扁平状鉄粒子の充填率を向上させることができる。これにより、成形品の磁気特性を向上させることができる。 The thickness of the flat iron particles may be 0.1 μm or more and 20 μm or less. In this case, it is possible to suppress an increase in the time required for pulverizing the iron particles in the pulverizing step. In addition, for example, when a mold is filled with flat iron particles to produce a molded product, the filling rate of the flat iron particles into the mold can be improved. Thereby, the magnetic properties of the molded product can be improved.
扁平状鉄粒子の厚さをｔ、扁平状鉄粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）をｄとした場合、扁平状鉄粒子のアスペクト比ｄ／ｔが１０以上であってもよい。この場合には、例えば扁平状鉄粒子を用いた成形品のヒステリシス損の低減等、磁気特性を向上させることができる。 When the thickness of the flat iron particles is t, and the diameter (the length of the widest part) of the flat iron particles in the direction orthogonal to the thickness direction is d, the aspect ratio of the flat iron particles is d/t. may be 10 or more. In this case, it is possible to improve magnetic properties such as reduction in hysteresis loss of a molded product using flat iron particles.
以下、本発明を実施例により説明し、比較例と比較する。なお、本発明は、この実施例に限定されるものではない。 Hereinafter, the present invention will be described with reference to examples and compared with comparative examples. However, the present invention is not limited to this embodiment.
（実施例１）
純鉄粒子（株式会社神戸製鋼製、品番：ＭＬ３５Ｎ）と窒化ホウ素（ナカライテスク株式会社製、商品名：窒化ホウ素、商品コード：０５２２４－７２）とアルコール（和光純薬工業株式会社製、商品名：２－プロパノール、商品コード：１６６－０４８３６）をボールミル（日陶科学株式会社製、型番：ＡＮＺ－５１Ｄ）に添加し、粉砕した。処理条件として、ミルへの純鉄粒子の投入量は２００ｇ、潤滑剤としての窒化ホウ素の添加量は３ｇ、アルコールの添加量は８０ｍｌ、球状媒体としてはφ１６ｍｍの鋼球（ＳＵＪ－２製）を９０個、ボールミル運転回転数３６０ｒｐｍ、処理時間７０ｈとした。
(Example 1)
Pure iron particles (manufactured by Kobe Steel, Ltd., product number: ML35N), boron nitride (manufactured by Nacalai Tesque Co., Ltd., product name: boron nitride, product code: 05224-72) and alcohol (manufactured by Wako Pure Chemical Industries, Ltd., product name : 2-propanol, product code: 166-04836) was added to a ball mill (manufactured by Nitto Kagaku Co., Ltd., model number: ANZ-51D) and pulverized. The processing conditions were as follows: 200 g of pure iron particles were fed into the mill, 3 g of boron nitride was added as a lubricant, 80 ml of alcohol was added, and φ16 mm steel balls (manufactured by SUJ-2) were used as spherical media. 90 pieces, ball mill operation speed of 360 rpm, and treatment time of 70 hours.
得られた鉄粒子を電子顕微鏡（日本電子株式会社製、ＪＣＭ－６０００等）及び粉末Ｘ線回折装置（リガク社製、Ｓｍａｒｔｌａｂ）で分析した。分析結果をそれぞれ図１、図２に示す。 The obtained iron particles were analyzed with an electron microscope (manufactured by JEOL Ltd., JCM-6000, etc.) and a powder X-ray diffractometer (manufactured by Rigaku, Smartlab). The analysis results are shown in FIGS. 1 and 2, respectively.
図１に示すように、上記粉砕処理によって粒状の鉄粒子から、扁平状の鉄粒子が得られた。粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）の平均は３９６μｍであった。また、厚さの平均は３．１４μｍであった。したがって、粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）と厚さの比で定義されるアスペクト比は１２６であった。 As shown in FIG. 1, flat iron particles were obtained from the granular iron particles by the pulverization process. The average diameter (the length of the widest part) in the direction orthogonal to the thickness direction of the particles was 396 μm. Also, the average thickness was 3.14 μm. Therefore, the aspect ratio defined as the ratio of the diameter (the length of the widest part) to the thickness in the direction orthogonal to the thickness direction of the grain was 126.
図２には、上記粉砕処理を行った鉄粒子の粉末Ｘ線回折パターンを示す。また、比較のため、上記粉砕処理前の鉄粒子の粉末Ｘ線回折パターンも合わせて示す。これによれば、後述の表１に示すように、（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａは、粉砕処理前の鉄粒子が０．２３、粉砕処理後の鉄粒子が７．９であった。ピーク強度比の変化から、粉砕処理後の鉄粒子には集合組織が形成されていることが確認された。 FIG. 2 shows the powder X-ray diffraction pattern of the iron particles subjected to the pulverization treatment. For comparison, the powder X-ray diffraction pattern of the iron particles before the pulverization treatment is also shown. According to this, as shown in Table 1 below, the peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane is 0.0 for the iron particles before the pulverization treatment. 23, and iron particles after pulverization were 7.9. From the change in the peak intensity ratio, it was confirmed that the iron particles after pulverization had a texture.
次に、上記粉砕処理を行った鉄粒子を管状電気炉（アズワン社製、ＴＭＦ－５００Ｎ）で焼鈍処理（熱処理）した。焼鈍雰囲気はＡｒ－３％Ｈ２、所定温度における保持時間は１ｈ、温度保持終了後の冷却は炉冷とした。 Next, the pulverized iron particles were annealed (heat treated) in a tubular electric furnace (TMF-500N, manufactured by AS ONE). The annealing atmosphere was Ar-3% H 2 , the holding time at the predetermined temperature was 1 hour, and the cooling after the temperature holding was furnace cooling.
上記焼鈍処理された扁平状鉄粒子をＥＢＳＤ（Ｅｌｅｃｔｒｏｎ Ｂａｃｋ Ｓｃａｔｔｅｒ Ｄｉｆｆｒａｃｔｉｏｎ）検出器（ＴＳＬ社製）付き電子顕微鏡（日本電子社製、ＪＩＢ－４６００Ｆ）及び粉末Ｘ線回折装置（リガク社製、Ｓｍａｒｔｌａｂ）で分析した。ＥＢＳＤ検出器付き電子顕微鏡は、試料のＫＡＭ（Ｋｅｒｎｅｌ Ａｖｅｒａｇｅ Ｍｉｓｏｒｉｅｎｔａｔｉｏｎ）マップを得るために用いられた。ＫＡＭマップを規定する測定値は、測定点とその隣接する全ての測定点間の方位の平均差であり、以後、結晶方位解析における「局所方位差」と表記する。分析結果をそれぞれ図３、図４に示す。 The annealed flat iron particles were subjected to an electron microscope (JIB-4600F, manufactured by JEOL Ltd.) equipped with an EBSD (Electron Back Scatter Diffraction) detector (manufactured by TSL) and a powder X-ray diffractometer (Smartlab, manufactured by Rigaku). analyzed in Electron microscopy with an EBSD detector was used to obtain KAM (Kernel Average Misorientation) maps of the samples. The measured value that defines a KAM map is the average difference in orientation between a measurement point and all its adjacent measurement points, henceforth referred to as "local misorientation" in crystallographic orientation analysis. The analysis results are shown in FIGS. 3 and 4, respectively.
図３には扁平状鉄粒子のＫＡＭマップを示す。また、後述の表２にはＫＡＭ値が１度以下の領域の面積率を示す。これによれば、上記粉砕処理によって得られた偏平状鉄粒子の表面には結晶方位解析における局所方位差が１度以下の箇所が４．３％と僅かな部分しかない。また、５００℃で熱処理した扁平状鉄粒子においても同様に１度以下の箇所が７．６％と僅かな部分となっている。一方、６００℃以上で熱処理された扁平状鉄粒子では１度以下の箇所が増加し、６００℃で熱処理された扁平状鉄粒子の場合、１度以下の箇所は４６．５％となった。これは６００℃以上で熱処理された扁平状鉄粒子は再結晶し、上記粉砕処理によって扁平状鉄粒子内部に導入された転位が消滅したためと推察される。 FIG. 3 shows a KAM map of flattened iron particles. Table 2 below shows area ratios of regions having a KAM value of 1 degree or less. According to this, on the surface of the flat iron particles obtained by the pulverization process, there are only 4.3% of the portions where the local misorientation is 1 degree or less in the crystal orientation analysis. Similarly, in the flattened iron particles heat-treated at 500° C., the portion having a temperature of 1 degree or less is as small as 7.6%. On the other hand, in the flat iron particles heat-treated at 600°C or higher, the number of points with a temperature of 1°C or less increased, and in the case of the flat iron particles heat-treated at 600°C, the number of points with a temperature of 1°C or less was 46.5%. It is presumed that this is because the flat iron particles heat-treated at 600° C. or higher are recrystallized and the dislocations introduced into the inside of the flat iron particles by the pulverization process are eliminated.
図４には上記焼鈍処理を行った扁平状鉄粒子の粉末Ｘ線回折パターンを示す。これによれば、後述の表１に示すように、（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａは、上記焼鈍処理における保持温度５００℃では１６．１、６００℃では１４．５、７００℃では９．３、８００℃では９．６であった。このように、再結晶が生じる６００℃以上の熱処理を施しても、本実施例によって得られる扁平状鉄粒子は８以上のピーク強度比Ｂ／Ａを示した。さらに、８００℃で熱処理を施しても９以上のピーク強度比Ｂ／Ａを示した。すなわち、強い配向性の集合組織を保持しつつ、結晶方位解析における局所方位差の小さい集合組織を持つことが確認された。 FIG. 4 shows the powder X-ray diffraction pattern of the flattened iron particles subjected to the annealing treatment. According to this, as shown in Table 1 below, the peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane is 16.1 at 600°C, 14.5 at 700°C, 9.3 at 700°C, and 9.6 at 800°C. As described above, the flat iron particles obtained in this example exhibited a peak intensity ratio B/A of 8 or more even after being subjected to a heat treatment at 600° C. or higher, which causes recrystallization. Furthermore, even after heat treatment at 800° C., the peak intensity ratio B/A of 9 or more was exhibited. That is, it was confirmed to have a texture with a small local misorientation in the crystal orientation analysis while maintaining a texture with strong orientation.
（実施例２）
純鉄粒子（株式会社神戸製鋼製、品番：ＭＬ３５Ｎ）と二硫化モリブデン（ＳＴＲＥＭ ＣＨＥＭＩＣＡＬＳ製、型式：９３－４２４７）をボールミル（日新技研社製、型番：ＮＥＶ－ＭＡ－８）に添加し、粉砕した。処理条件として、ミルへの純鉄粒子の投入量は５ｇ、潤滑剤としての二硫化モリブデンの添加量は０．０３ｇ、球状媒体としてはφ９．５２ｍｍの鋼球（ＳＵＪ－２製）を２０個、処理時間２ｈとした。
(Example 2)
Pure iron particles (manufactured by Kobe Steel, Ltd., product number: ML35N) and molybdenum disulfide (manufactured by STREM CHEMICALS, model: 93-4247) are added to a ball mill (manufactured by Nisshin Giken, model number: NEV-MA-8), pulverized. As the processing conditions, the amount of pure iron particles charged to the mill was 5 g, the amount of molybdenum disulfide added as a lubricant was 0.03 g, and 20 steel balls (manufactured by SUJ-2) of φ9.52 mm were used as spherical media. , and the processing time was 2 h.
得られた鉄粒子を電子顕微鏡（日本電子株式会社製、ＪＣＭ－６０００等）及び粉末Ｘ線回折装置（リガク社製、Ｓｍａｒｔｌａｂ）で分析した。結果をそれぞれ図５、図６に示す。 The obtained iron particles were analyzed with an electron microscope (manufactured by JEOL Ltd., JCM-6000, etc.) and a powder X-ray diffractometer (manufactured by Rigaku, Smartlab). The results are shown in FIGS. 5 and 6, respectively.
図５に示すように、上記粉砕処理によって粒状の鉄粒子から、扁平状の鉄粒子が得られた。粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）の平均は４５５μｍであった。また、厚さの平均は１．５４μｍであった。したがって、粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）と厚さの比で定義されるアスペクト比は２９５であった。 As shown in FIG. 5, flat iron particles were obtained from the granular iron particles by the pulverization process. The average diameter (the length of the widest part) in the direction orthogonal to the thickness direction of the particles was 455 μm. Also, the average thickness was 1.54 μm. Therefore, the aspect ratio defined as the ratio of the diameter (the length of the widest part) to the thickness in the direction orthogonal to the thickness direction of the grain was 295.
図６には上記粉砕処理を行った鉄粒子の粉末Ｘ線回折パターンを示す。また、比較のため、上記粉砕処理前の鉄粒子の粉末Ｘ線回折パターンも合わせて示す。これによれば、後述の表１に示すように、（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａは、粉砕処理前の鉄粒子の場合０．２３で、粉砕処理後の鉄粒子の場合５７．３であった。ピーク強度比の変化から、粉砕処理後の鉄粒子には集合組織が形成されていることが確認された。 FIG. 6 shows the powder X-ray diffraction pattern of the iron particles subjected to the pulverization treatment. For comparison, the powder X-ray diffraction pattern of the iron particles before the pulverization treatment is also shown. According to this, as shown in Table 1 below, the peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane is 0 in the case of the iron particles before the pulverization treatment. .23 and 57.3 for the iron particles after the milling process. From the change in the peak intensity ratio, it was confirmed that the iron particles after pulverization had a texture.
次に、上記粉砕処理を行った鉄粒子を管状電気炉（アズワン社製、ＴＭＦ－５００Ｎ）で焼鈍処理（熱処理）した。焼鈍雰囲気はＡｒ－３％Ｈ２、所定温度における保持時間は１ｈ、温度保持終了後の冷却は炉冷とした。 Next, the pulverized iron particles were annealed (heat treated) in a tubular electric furnace (TMF-500N, manufactured by AS ONE). The annealing atmosphere was Ar-3% H 2 , the holding time at the predetermined temperature was 1 hour, and the cooling after the temperature holding was furnace cooling.
上記焼鈍処理された扁平状鉄粒子をＥＢＳＤ（Ｅｌｅｃｔｒｏｎ Ｂａｃｋ Ｓｃａｔｔｅｒ Ｄｉｆｆｒａｃｔｉｏｎ）検出器（ＴＳＬ社製）付き電子顕微鏡（日本電子社製、ＪＩＢ－４６００Ｆ）及び粉末Ｘ線回折装置（リガク社製、Ｓｍａｒｔｌａｂ）で分析した。ＥＢＳＤ付き電子顕微鏡は、試料のＫＡＭ（Ｋｅｒｎｅｌ Ａｖｅｒａｇｅ Ｍｉｓｏｒｉｅｎｔａｔｉｏｎ）マップを得るために用いられた。分析結果をそれぞれ図７、図８に示す。 The annealed flat iron particles were subjected to an electron microscope (JIB-4600F, manufactured by JEOL Ltd.) equipped with an EBSD (Electron Back Scatter Diffraction) detector (manufactured by TSL) and a powder X-ray diffractometer (Smartlab, manufactured by Rigaku). analyzed in Electron microscopy with EBSD was used to obtain KAM (Kernel Average Misorientation) maps of the samples. The analysis results are shown in FIGS. 7 and 8, respectively.
図７には扁平状鉄粒子のＫＡＭマップを示す。また、後述の表２にはＫＡＭ値が１度以下の領域の面積率を示す。これによれば、上記粉砕処理によって得られた扁平状鉄粒子の表面には結晶方位解析における局所方位差が１度以下の箇所は５．４％と僅かな部分でしかない。また、５００℃で熱処理した扁平状鉄粒子においても同様に１度以下の箇所が１０．４％と僅かな部分となっている。一方、６００℃以上で熱処理された扁平状鉄粒子では１度以下の箇所は増加し、６００℃で熱処理された扁平状鉄粒子の場合、１度以下の箇所は２５．１％となった。これは６００℃以上で熱処理された扁平状鉄粒子は再結晶し、上記粉砕処理によって扁平状鉄粒子内部に導入された転位が消滅したためと推察される。 FIG. 7 shows a KAM map of flattened iron particles. Table 2 below shows area ratios of regions having a KAM value of 1 degree or less. According to this, only 5.4% of the surfaces of the flattened iron particles obtained by the pulverization process have a local misorientation of 1 degree or less in the crystal orientation analysis. Similarly, in the flattened iron particles heat-treated at 500° C., the portion having a temperature of 1 degree or less is as small as 10.4%. On the other hand, in the flat iron particles heat-treated at 600°C or higher, the number of points with a temperature of 1°C or less increased, and in the case of the flat iron particles heat-treated at 600°C, the number of points with a temperature of 1°C or less was 25.1%. It is presumed that this is because the flat iron particles heat-treated at 600° C. or higher are recrystallized and the dislocations introduced into the inside of the flat iron particles by the pulverization process are eliminated.
図８には上記焼鈍処理を行った扁平状鉄粒子の粉末Ｘ線回折パターンを示す。これによれば、後述の表１に示すように、（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａは、上記焼鈍処理における保持温度５００℃では８７．７、６００℃では１４４．７、７００℃では６０．１、８００℃では４１．１であった。このように、再結晶が生じる６００℃以上の熱処理を施しても、本実施例によって得られる扁平状鉄粒子は８以上のピーク強度比Ｂ／Ａを示した。さらに、８００℃で熱処理を施しても９以上のピーク強度比Ｂ／Ａを示した。すなわち、強い配向性の集合組織を保持しつつ、結晶方位解析における局所方位差の小さい集合組織を持つことが確認された。 FIG. 8 shows the powder X-ray diffraction pattern of the flattened iron particles subjected to the annealing treatment. According to this, as shown in Table 1 below, the peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane is 87.7, 144.7 at 600°C, 60.1 at 700°C, and 41.1 at 800°C. As described above, the flat iron particles obtained in this example exhibited a peak intensity ratio B/A of 8 or more even after being subjected to a heat treatment at 600° C. or higher, which causes recrystallization. Furthermore, even after heat treatment at 800° C., the peak intensity ratio B/A of 9 or more was exhibited. That is, it was confirmed to have a texture with a small local misorientation in the crystal orientation analysis while maintaining a texture with strong orientation.
（比較例）
純鉄粒子（株式会社神戸製鋼製、品番：ＭＬ３５Ｎ）と潤滑油（呉工業株式会社製、５－５６）をボールミル（日陶科学株式会社製、型番：ＡＮＺ－５１Ｄ）に添加し、粉砕した。処理条件として、ミルへの純鉄粒子の投入量は２００ｇ、潤滑油の添加量は２５０ｍｌ、球状媒体としてはφ１６ｍｍの鋼球（ＳＵＪ－２製）を１００個、ボールミル運転回転数３６０ｒｐｍ、処理時間７０ｈとした。
(Comparative example)
Pure iron particles (manufactured by Kobe Steel, Ltd., product number: ML35N) and lubricating oil (manufactured by Kure Kogyo Co., Ltd., 5-56) were added to a ball mill (manufactured by Nitto Kagaku Co., Ltd., model number: ANZ-51D) and pulverized. . As processing conditions, the amount of pure iron particles put into the mill is 200 g, the amount of lubricating oil added is 250 ml, 100 φ16 mm steel balls (manufactured by SUJ-2) are used as spherical media, the ball mill operation speed is 360 rpm, and the processing time is 70 hours.
得られた鉄粒子を電子顕微鏡（日本電子株式会社製、ＪＣＭ－６０００）及び粉末Ｘ線回折装置（リガク社製、Ｓｍａｒｔｌａｂ）で分析した。分析結果をそれぞれ図９、図１０に示す。 The obtained iron particles were analyzed with an electron microscope (manufactured by JEOL Ltd., JCM-6000) and a powder X-ray diffractometer (manufactured by Rigaku, Smartlab). The analysis results are shown in FIGS. 9 and 10, respectively.
図９に示すように、上記粉砕処理によって粒状の鉄粒子から、扁平状の鉄粒子が得られた。粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）の平均は３２６μｍであった。また、厚さの平均は３．７８μｍであった。したがって、粒子の厚さ方向と直交する方向における径（最も幅の広い箇所の長さ）と厚さの比で定義されるアスペクト比は８６であった。 As shown in FIG. 9, flat iron particles were obtained from the granular iron particles by the pulverization process. The average diameter (the length of the widest part) in the direction orthogonal to the thickness direction of the particles was 326 μm. Also, the average thickness was 3.78 μm. Therefore, the aspect ratio defined as the ratio of the diameter (the length of the widest part) to the thickness in the direction orthogonal to the thickness direction of the grain was 86.
図１０には上記粉砕処理を行った鉄粒子の粉末Ｘ線回折パターンを示す。また、比較のため、上記粉砕処理前の鉄粒子の粉末Ｘ線回折パターンも合わせて示す。これによれば、後述の表１に示すように、（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａは、粉砕処理前の鉄粒子の場合０．２３で、粉砕処理後の鉄粒子の場合１１．７であった。ピーク強度比の変化から、粉砕処理後の鉄粒子には集合組織が形成されていることが確認された。 FIG. 10 shows the powder X-ray diffraction pattern of the iron particles subjected to the pulverization treatment. For comparison, the powder X-ray diffraction pattern of the iron particles before the pulverization treatment is also shown. According to this, as shown in Table 1 below, the peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane is 0 in the case of the iron particles before the pulverization treatment. 0.23 and 11.7 for the iron particles after milling. From the change in the peak intensity ratio, it was confirmed that the iron particles after pulverization had a texture.
次に、上記粉砕処理を行った鉄粒子を管状電気炉（アズワン社製、ＴＭＦ－５００Ｎ）で焼鈍処理（熱処理）した。焼鈍雰囲気はＡｒ－３％Ｈ２、所定温度における保持時間は１ｈ、温度保持終了後の冷却は炉冷とした。 Next, the pulverized iron particles were annealed (heat treated) in a tubular electric furnace (TMF-500N, manufactured by AS ONE). The annealing atmosphere was Ar-3% H 2 , the holding time at the predetermined temperature was 1 hour, and the cooling after the temperature holding was furnace cooling.
上記焼鈍処理された扁平状鉄粒子をＥＢＳＤ（Ｅｌｅｃｔｒｏｎ Ｂａｃｋ Ｓｃａｔｔｅｒ Ｄｉｆｆｒａｃｔｉｏｎ）検出器（ＴＳＬ社製）付き電子顕微鏡（日本電子社製、ＪＩＢ－４６００Ｆ）及び粉末Ｘ線回折装置（リガク社製、Ｓｍａｒｔｌａｂ）で分析した。ＥＢＳＤ付き電子顕微鏡は、試料のＫＡＭ（Ｋｅｒｎｅｌ Ａｖｅｒａｇｅ Ｍｉｓｏｒｉｅｎｔａｔｉｏｎ）マップを得るために用いられた。分析結果をそれぞれ図１１、図１２に示す。 The annealed flat iron particles were subjected to an electron microscope (JIB-4600F, manufactured by JEOL Ltd.) equipped with an EBSD (Electron Back Scatter Diffraction) detector (manufactured by TSL) and a powder X-ray diffractometer (Smartlab, manufactured by Rigaku). analyzed in Electron microscopy with EBSD was used to obtain KAM (Kernel Average Misorientation) maps of the samples. The analysis results are shown in FIGS. 11 and 12, respectively.
図１１には扁平状鉄粒子のＫＡＭマップを示す。また、後述の表２にはＫＡＭ値が１度以下の領域の面積率を示す。これによれば、上記粉砕処理によって得られた偏平状鉄粒子の表面には結晶方位解析における局所方位差が１度以下の箇所が４．１％と僅かな部分でしかない。また、５００℃で熱処理した扁平状鉄粒子においても同様に１度以下の箇所が２．３％と僅かな部分となっている。一方、６００℃以上で熱処理された扁平状鉄粒子では１度以下の箇所は増加し、６００℃で熱処理された扁平状鉄粒子の場合、１度以下の箇所は４１．２％となった。これは６００℃以上で熱処理された扁平状鉄粒子は再結晶し、上記粉砕処理によって扁平状鉄粒子内部に導入された転位が消滅したためと推察される。 FIG. 11 shows a KAM map of flattened iron particles. Table 2 below shows area ratios of regions having a KAM value of 1 degree or less. According to this, on the surface of the flat iron particles obtained by the pulverization process, there are only 4.1% of the portions where the local misorientation is 1 degree or less in the crystal orientation analysis. Similarly, in the flattened iron particles heat-treated at 500° C., the portion having a temperature of 1 degree or less is as small as 2.3%. On the other hand, in the flat iron particles heat-treated at 600°C or higher, the number of points with a temperature of 1°C or less increased, and in the case of the flat iron particles heat-treated at 600°C, the number of points with a temperature of 1°C or less was 41.2%. It is presumed that this is because the flat iron particles heat-treated at 600° C. or higher are recrystallized and the dislocations introduced into the inside of the flat iron particles by the pulverization process are eliminated.
図１２には上記焼鈍処理を行った扁平状鉄粒子の粉末Ｘ線回折パターンを示す。これによれば、後述の表１に示すように、（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａは、上記焼鈍処理における保持温度５００℃では１６．２、６００℃では７．７、７００℃では２．１、８００℃では１．４であった。このように、再結晶が生じる６００℃以上の熱処理を施すと、本比較例によって得られる偏平状鉄粒子は８未満の比較的小さいピーク強度比Ｂ／Ａを示した。すなわち、結晶方位解析における局所方位差は小さいが、実施例１、２と比較して相対的に配向性が弱い集合組織を持つことが確認された。 FIG. 12 shows the powder X-ray diffraction pattern of the flattened iron particles subjected to the annealing treatment. According to this, as shown in Table 1 below, the peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane is 16.2 at 600°C, 7.7 at 700°C, 2.1 at 700°C, and 1.4 at 800°C. Thus, when heat treatment at 600° C. or higher, which causes recrystallization, was performed, the flat iron particles obtained in this comparative example showed a relatively small peak intensity ratio B/A of less than 8. That is, it was confirmed that although the local orientation difference in the crystal orientation analysis was small, it had a relatively weak texture as compared with Examples 1 and 2.
（その他の実施形態）
本発明は、上記実施形態に何ら限定されるものではなく、本発明を逸脱しない範囲において種々の態様で実施しうることはいうまでもない。
(Other embodiments)
The present invention is by no means limited to the above embodiments, and it goes without saying that various aspects can be implemented without departing from the scope of the present invention.
上記実施形態における１つの構成要素が有する機能を複数の構成要素として分散させたり、複数の構成要素が有する機能を１つの構成要素に統合したりしてもよい。また、上記実施形態の構成の一部を省略してもよい。また、上記実施形態の構成の少なくとも一部を、他の上記実施形態の構成に対して付加、置換等してもよい。なお、特許請求の範囲に記載の文言から特定される技術思想に含まれるあらゆる態様が本発明の実施形態である。
The function of one component in the above embodiments may be distributed as multiple components, or the functions of multiple components may be integrated into one component. Also, part of the configuration of the above embodiment may be omitted. Also, at least a part of the configuration of the above embodiment may be added, replaced, etc. with respect to the configuration of the other above embodiment. In addition, every aspect included in the technical idea specified from the wording of the claim is an embodiment of the present invention.
Claims (9)
Ｘ線回折において（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａが８以上であり、かつ、結晶方位解析において局所方位差が１度以下の領域が２０％以上である集合組織を有する、扁平状鉄粒子。 Flat iron particles made of pure iron ,
A region in which the peak intensity ratio B/A between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane in X-ray diffraction is 8 or more, and the local misorientation is 1 degree or less in the crystal orientation analysis. Flattened iron particles having a texture of 20% or more.
窒化ホウ素を含む潤滑剤を用いて純鉄粒子を粉砕する粉砕工程と、
扁平状に粉砕した前記純鉄粒子を焼鈍する焼鈍工程と、を有し、
前記扁平状鉄粒子は、Ｘ線回折において（１１０）面のピーク強度Ａと（００２）面のピーク強度Ｂとのピーク強度比Ｂ／Ａが８以上であり、かつ、結晶方位解析において局所方位差が１度以下の領域が２０％以上である集合組織を有する、扁平状鉄粒子の製造方法。 A method for producing flat iron particles made of pure iron , comprising:
A pulverizing step of pulverizing pure iron particles using a lubricant containing boron nitride ;
An annealing step of annealing the pure iron particles crushed into a flat shape ,
The flat iron particles have a peak intensity ratio B/A of 8 or more between the peak intensity A of the (110) plane and the peak intensity B of the (002) plane in X-ray diffraction, and the local orientation in the crystal orientation analysis A method for producing flattened iron particles having a texture in which 20% or more of the area has a difference of 1 degree or less .
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005281783A (en) | 2004-03-30 | 2005-10-13 | Nec Tokin Corp | Soft magnetic powder for noise suppression, production method therefor and noise suppression sheet using the same |
| JP2010196123A (en) | 2009-02-26 | 2010-09-09 | Daido Steel Co Ltd | Method for producing flattened soft magnetic powder, flattened soft magnetic powder and electromagnetic wave absorber |
| WO2015151486A1 (en) | 2014-04-02 | 2015-10-08 | Ｊｆｅスチール株式会社 | Iron powder for dust core, and sorting method for iron powder for dust core |
| WO2016167286A1 (en) | 2015-04-13 | 2016-10-20 | 独立行政法人 国立高等専門学校機構 | Flat metal particle, molded article having flat metal particle, method for manufacturing flat metal particle, and method for manufacturing metal plate |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005281783A (en) | 2004-03-30 | 2005-10-13 | Nec Tokin Corp | Soft magnetic powder for noise suppression, production method therefor and noise suppression sheet using the same |
| JP2010196123A (en) | 2009-02-26 | 2010-09-09 | Daido Steel Co Ltd | Method for producing flattened soft magnetic powder, flattened soft magnetic powder and electromagnetic wave absorber |
| WO2015151486A1 (en) | 2014-04-02 | 2015-10-08 | Ｊｆｅスチール株式会社 | Iron powder for dust core, and sorting method for iron powder for dust core |
| WO2016167286A1 (en) | 2015-04-13 | 2016-10-20 | 独立行政法人 国立高等専門学校機構 | Flat metal particle, molded article having flat metal particle, method for manufacturing flat metal particle, and method for manufacturing metal plate |
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