WO2023106221A1 - PRODUCTION METHOD FOR ANISOTROPIC Nd-Fe-B MAGNETIC POWDER - Google Patents

PRODUCTION METHOD FOR ANISOTROPIC Nd-Fe-B MAGNETIC POWDER Download PDF

Info

Publication number
WO2023106221A1
WO2023106221A1 PCT/JP2022/044508 JP2022044508W WO2023106221A1 WO 2023106221 A1 WO2023106221 A1 WO 2023106221A1 JP 2022044508 W JP2022044508 W JP 2022044508W WO 2023106221 A1 WO2023106221 A1 WO 2023106221A1
Authority
WO
WIPO (PCT)
Prior art keywords
magnetic powder
anisotropic
temperature
hydrogen
furnace
Prior art date
Application number
PCT/JP2022/044508
Other languages
French (fr)
Japanese (ja)
Inventor
修平 上川
梢 松前
信宏 片山
Original Assignee
戸田工業株式会社
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 戸田工業株式会社 filed Critical 戸田工業株式会社
Priority to CN202280069088.5A priority Critical patent/CN118120033A/en
Priority to JP2023566283A priority patent/JPWO2023106221A1/ja
Publication of WO2023106221A1 publication Critical patent/WO2023106221A1/en

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/14—Treatment of metallic powder
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/02—Making ferrous alloys by powder metallurgy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/047—Alloys characterised by their composition
    • H01F1/053—Alloys characterised by their composition containing rare earth metals
    • H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
    • H01F1/057—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets

Definitions

  • the present invention relates to a method for producing anisotropic Nd--Fe--B magnetic powder.
  • Bonded magnets have advantages such as flexibility in shape and high dimensional accuracy, so they have been widely used in various applications such as electrical products and automobile parts. In recent years, as electronic products and automobile parts have become smaller and lighter, there has been a strong demand for bond magnets themselves to have higher performance and higher heat resistance to withstand harsh environments.
  • Bonded magnets are generally manufactured by kneading binder resin such as rubber or plastic material and magnetic powder, and then molding the mixture.
  • binder resin such as rubber or plastic material and magnetic powder
  • it is necessary to improve the performance of the magnetic powder that is, to have a large residual magnetic flux density Br and a high coercive force iHc, and as a result, a magnetic powder having a large maximum magnetic energy product (BH) max . strongly requested.
  • Magnetic powders include magnetoplumbite-type ferrites such as barium ferrite and strontium ferrite, Nd--Fe--B magnetic powders, and Sm--Fe--N magnetic powders.
  • Nd-Fe-B magnetic powder has high saturation magnetization and anisotropic magnetic field, so it is widely used in high-efficiency motors. It is also widely used in large magnetic circuits such as devices.
  • anisotropic conversion of magnetic powder by HDDR (Hydrogenation-Decomposition-Desorption-Recombination) treatment is known as a method for improving the characteristics of Nd-Fe-B magnetic powder.
  • HDDR treatment anisotropic Nd--Fe--B system magnetic powder is obtained by adsorption and desorption of hydrogen to Nd--Fe--B system magnetic powder.
  • an anisotropic Nd--Fe--B system magnetic powder is produced by pulverizing an Nd--Fe--B system magnet that has been made anisotropic by hot working by a disk atomizing method.
  • Patent document 2 describes a method of hot working a cast alloy, heat-treating it in a hydrogen gas atmosphere to absorb hydrogen, dehydrogenating it in a vacuum, and pulverizing it to obtain a magnet powder. It is
  • Patent Document 3 describes a method for manufacturing an anisotropic permanent magnet in which crystal grains are refined by hot working a cast ingot at a temperature of 500° C. or higher and the crystal axis is oriented in a specific direction. It is
  • Patent Document 2 describes that a hot-worked cast alloy is heat-treated in a hydrogen atmosphere to absorb hydrogen, and then dehydrogenated in a vacuum and pulverized.
  • the temperature for hydrogen absorption and dehydrogenation in the examples is 750° C. or higher, which is the temperature generally used in the HDDR method.
  • the magnetic properties of the obtained anisotropic Nd--Fe--B magnetic powder were not satisfactory.
  • Patent Document 3 a hot-worked cast ingot is pulverized with hydrogen, but the conditions for dehydrogenation in a vacuum after absorbing hydrogen are at room temperature.
  • the magnetic properties of the obtained anisotropic Nd--Fe--B magnetic powder were not satisfactory.
  • An object of the present invention is to produce an anisotropic Nd--Fe--B magnetic powder that has an excellent iHc and is fine particles.
  • the present inventors conducted extensive studies and found out what temperature was appropriate for the hydrogen absorption step and the dehydrogenation step of the conventional HDDR process for the Nd-Fe-B system hot-worked magnet.
  • the inventors have found that anisotropic Nd--Fe--B magnetic powder having surprisingly excellent magnetic properties can be obtained by performing the treatment in a completely different temperature range, and have completed the present invention.
  • the present invention relates to a method for producing an Nd--Fe--B system magnetic powder in which a hydrogen embrittlement treatment including a hydrogen absorption process and a dehydrogenation process is performed on an Nd--Fe--B system hot-worked magnet, wherein the dehydration
  • a method for producing an anisotropic Nd--Fe--B magnetic powder characterized in that the pretreatment is carried out at a temperature of 150° C. or more and less than 500° C. (first gist of the present invention).
  • the hydrogen absorption step is performed at a temperature of 30°C or higher and 400°C or lower in a hydrogen atmosphere (second gist of the present invention).
  • the pressure in the furnace in the hydrogen absorbing step is 1013 hPa or more and 1070 hPa or less (the third gist of the present invention).
  • the dehydrogenation step it is preferable to evacuate until the pressure in the furnace reaches 100 Pa or less (the fourth gist of the present invention).
  • the anisotropic Nd-Fe-B system which has excellent magnetic properties and is fine particles with little strain on the Nd-Fe-B structure when the hot-worked magnet is pulverized Magnetic powders can be produced.
  • 4 is a graph showing the relationship between the dehydrogenation temperature and the iHc of the anisotropic Nd--Fe--B magnetic powder of the present invention. 4 is a graph showing the relationship between the hydrogen storage temperature and the particle size of the anisotropic Nd--Fe--B magnetic powder of the present invention.
  • an Nd--Fe--B hot-worked magnet is subjected to hydrogen embrittlement treatment to obtain an anisotropic Nd--Fe--B magnetic powder. It is.
  • a Nd--Fe--B system hot-worked magnet can be obtained, for example, by hot-working a ribbon produced by a melt spinning method by a die upset method. A magnet obtained by this hot working exhibits anisotropy.
  • the composition of the Nd--Fe--B system hot-worked magnet is composed of Nd 2 Fe 14 B as the main phase and additive elements A (A: Pr, Tb, Dy, Co, Ni, Cu, Al, Zr, Ga, Si, Ti , V, Cr, Nb, Mo, Hf, Ta, W).
  • additive elements A A: Pr, Tb, Dy, Co, Ni, Cu, Al, Zr, Ga, Si, Ti , V, Cr, Nb, Mo, Hf, Ta, W.
  • hydrogen embrittlement treatment refers to a treatment that includes a hydrogen absorption process and a dehydrogenation process.
  • the Nd--Fe--B system hot-worked magnet is made to absorb hydrogen gas, and the accompanying volume expansion is used to generate many cracks in the Nd--Fe--B system hot-worked magnet.
  • the treatment temperature in the hydrogen absorption process is preferably 30°C or higher and 400°C or lower.
  • the reason why the treatment temperature is set at 30° C. or higher and 400° C. or lower is that at temperatures below 30° C. and above 400° C., the hydrogen absorption reaction does not progress easily and the particle size of the anisotropic Nd—Fe—B magnetic powder becomes large. It is for the sake of becoming.
  • the hydrogen absorption temperature is more preferably 50°C or higher and 300°C or lower, and still more preferably 80°C or higher and 230°C or lower.
  • the hydrogen absorption process is performed under a hydrogen atmosphere.
  • it is desirable to flow hydrogen so that the pressure inside the furnace is 1013 hPa or higher.
  • the reason why the pressure in the furnace is set to 1013 hPa or more is to reduce the possibility of air entering the furnace.
  • the furnace pressure is more preferably 1013 hPa or more and 1070 hPa or less.
  • the reason why the pressure in the furnace is set to 1070 hPa or less is to reduce the risk that the pressure in the furnace becomes excessively high and hydrogen leaks from other than the exhaust valve.
  • the treatment time in the hydrogen absorption process is preferably 1 hour or more and 3 hours and 30 minutes or less.
  • the hydrogen absorbed in the Nd-Fe-B system hot-worked magnet in the hydrogen absorption process is desorbed under reduced pressure.
  • the treatment temperature in the dehydrogenation process is 150°C or higher and lower than 500°C.
  • the reason why the treatment temperature is set to 150° C. or higher is that if the temperature is lower than 150° C., the iHc decreases due to insufficient dehydrogenation.
  • the reason why the temperature is less than 500° C. is that iHc decreases at a temperature of 500° C. or higher, and the reason for this is thought to be that the grain boundary phase between the Nd—Fe—B structures changes.
  • the dehydrogenation temperature is more preferably 200° C. or higher and 400° C. or lower, and still more preferably 270° C. or higher and 330° C. or lower.
  • the furnace pressure in the dehydrogenation step is more preferably 10 Pa or less, and still more preferably 1 Pa or less.
  • the treatment time of the dehydrogenation process is 1 hour or more and 18 hours or less.
  • the pressure inside the furnace is restored with an inert gas, the inside of the furnace is cooled to room temperature, and the hot-worked magnet subjected to the hydrogen embrittlement treatment is cracked to obtain an anisotropic Nd--Fe--B magnet.
  • a system magnetic powder can be obtained.
  • the particle size of the anisotropic Nd--Fe--B magnetic powder is preferably 400 ⁇ m or less.
  • the reason why the grain size is set to 400 ⁇ m or less is to facilitate molding in the production of bonded magnets.
  • the particle size is more preferably 200 ⁇ m or less, still more preferably 150 ⁇ m or less.
  • the coercive force (iHc) of the anisotropic Nd--Fe--B magnetic powder is preferably 15 kOe or more.
  • the reason why iHc is set to 15 kOe or more is to manufacture a heat-resistant bonded magnet.
  • iHc is more preferably 18 kOe or more.
  • the median diameter (d50) was measured.
  • a laser microsizer MS-2000e manufactured by Seishin Enterprise Co., Ltd. was used to analyze the median diameter (d50).
  • Example 1 (Hydrogen absorption process) The Nd--Fe--B system hot-worked magnet was put into a heat treatment furnace in an Ar atmosphere, and the inside of the heat treatment furnace was heated to 200.degree. When the temperature in the heat treatment furnace reached 200° C., the atmosphere was replaced from Ar to H 2 , and a hydrogen absorption step was performed in which heat treatment was performed at 200° C. for 70 minutes while introducing H 2 . The pressure inside the heat treatment furnace was 1060 hPa.
  • Example 2 Magnetic powder was obtained by carrying out the treatment in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 200° C. for 60 minutes, and the temperature and treatment time in the dehydrogenation step were 300° C. and 145 minutes, respectively. rice field.
  • Example 3 Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150°C and 80 minutes, respectively, and the temperature and treatment time in the dehydrogenation step were 300°C and 200 minutes, respectively. rice field.
  • Example 4 Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150°C and 170 minutes, respectively, and the temperature and treatment time in the dehydrogenation step were 400°C and 200 minutes, respectively. rice field.
  • Example 5 Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150°C and 170 minutes, respectively, and the temperature and treatment time in the dehydrogenation step were 450°C and 200 minutes, respectively. rice field.
  • Example 6 Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 110°C and 170 minutes respectively, and the temperature and treatment time in the dehydrogenation step were 300°C and 1080 minutes. rice field.
  • Example 7 Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 320° C. for 60 minutes, and the temperature and treatment time in the dehydrogenation step were 300° C. and 55 minutes, respectively. rice field.
  • Comparative Example 1 Magnetic powder was obtained by carrying out the treatment in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 100° C. for 70 minutes, and the temperature and treatment time in the dehydrogenation step were 100° C. and 1050 minutes. rice field.
  • Comparative Example 2 Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150° C. for 80 minutes, and the temperature and treatment time in the dehydrogenation step were 550° C. and 200 minutes, respectively. rice field.
  • Table 1 shows the manufacturing conditions, magnetic properties, and particle size (median diameter) of the magnetic powders of Examples 1 to 7 and Comparative Examples 1 and 2.
  • iHc of the magnetic powder produced at a dehydrogenation temperature of 100°C in Comparative Example 1 was lower. Further, the iHc of the magnetic powder produced at a dehydrogenation temperature of 550° C. in Comparative Example 2 was lower than that in Example 3. As shown in FIG. 1, iHc tended to show a maximum value around 300° C. in these examples. In all of the examples, fine magnetic powder was obtained by the hydrogen embrittlement treatment, but as shown in FIG. There was a tendency to
  • the present invention can produce anisotropic Nd--Fe--B magnetic powder that has excellent magnetic properties and is fine particles, it is useful for improving the performance of bonded magnets using this.

Landscapes

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

Abstract

Provided is a production method for a fine-particle anisotropic Nd-Fe-B magnetic powder that has excellent magnetic characteristics.　According to the present invention, a production method for an anisotropic Nd-Fe-B magnetic powder involves performing a hydrogen embrittlement treatment that includes a hydrogen absorption step and a dehydrogenation step on an Nd-Fe-B hot-worked magnet. The production method is characterized in that the dehydrogenation step is performed at a temperature of at least 150°C but less than 500°C.

Description

異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法Method for producing anisotropic Nd--Fe--B magnetic powder
　本発明は異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法に関するものである。 The present invention relates to a method for producing anisotropic Nd--Fe--B magnetic powder.
　ボンド磁石は、その形状自在性や高寸法精度などの利点がある為、従来から電気製品や自動車部品等の各種用途に広く使用されている。近年、電気製品や自動車部品の小型・軽量化に伴って、使用されるボンド磁石自体の高性能化及び苛酷な環境にも耐えうる高耐熱性が強く要求されている。 Bonded magnets have advantages such as flexibility in shape and high dimensional accuracy, so they have been widely used in various applications such as electrical products and automobile parts. In recent years, as electronic products and automobile parts have become smaller and lighter, there has been a strong demand for bond magnets themselves to have higher performance and higher heat resistance to withstand harsh environments.
　ボンド磁石は、一般に、ゴム又はプラスチック材料等の結合剤樹脂と磁性粉末とを混練した後、成形することによって製造されている。ボンド磁石の高性能化のためには磁性粉末の高性能化、即ち大きな残留磁束密度Ｂｒと高い保磁力ｉＨｃとを有し、その結果、大きな最大磁気エネルギー積（ＢＨ）ｍａｘを有する磁性粉末が強く要求されている。 Bonded magnets are generally manufactured by kneading binder resin such as rubber or plastic material and magnetic powder, and then molding the mixture. In order to improve the performance of the bonded magnet, it is necessary to improve the performance of the magnetic powder, that is, to have a large residual magnetic flux density Br and a high coercive force iHc, and as a result, a magnetic powder having a large maximum magnetic energy product (BH) max . strongly requested.
　磁性粉末としては、バリウムフェライトやストロンチウムフェライト等のマグネトプランバイト型フェライトやＮｄ－Ｆｅ－Ｂ系磁性粉末及びＳｍ－Ｆｅ－Ｎ系磁性粉末が知られている。特にＮｄ－Ｆｅ－Ｂ系磁性粉末は飽和磁化と異方性磁界がともに高いことから高効率モータに幅広く展開され、自動車、各種家電製品をはじめとして、磁気医療診断装置（ＭＲＩ）や放射光発生装置などの大型磁気回路にも広く用いられている。 Magnetic powders include magnetoplumbite-type ferrites such as barium ferrite and strontium ferrite, Nd--Fe--B magnetic powders, and Sm--Fe--N magnetic powders. In particular, Nd-Fe-B magnetic powder has high saturation magnetization and anisotropic magnetic field, so it is widely used in high-efficiency motors. It is also widely used in large magnetic circuits such as devices.
　一般にＮｄ－Ｆｅ－Ｂ系磁性粉末の高特性化の方法としてはＨＤＤＲ（Ｈｙｄｒｏｇｅｎａｔｉｏｎ－Ｄｅｃｏｍｐｏｓｉｔｉｏｎ－Ｄｅｓｏｒｐｔｉｏｎ　－Ｒｅｃｏｍｂｉｎａｔｉｏｎ）処理による磁性粉末の異方化が知られている。ＨＤＤＲ処理ではＮｄ－Ｆｅ－Ｂ系磁性粉末への水素の吸脱着により異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を得ている。 Generally, anisotropic conversion of magnetic powder by HDDR (Hydrogenation-Decomposition-Desorption-Recombination) treatment is known as a method for improving the characteristics of Nd-Fe-B magnetic powder. In HDDR treatment, anisotropic Nd--Fe--B system magnetic powder is obtained by adsorption and desorption of hydrogen to Nd--Fe--B system magnetic powder.
　その他の異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を得る方法として、異方性Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石の機械粉砕が知られている。特許文献１では熱間加工により異方化させたＮｄ－Ｆｅ－Ｂ系磁石をディスクアトマイズ法で粉砕することにより、異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を作製している。 As another method for obtaining anisotropic Nd--Fe--B system magnetic powder, mechanical pulverization of anisotropic Nd--Fe--B system hot worked magnets is known. In Patent Document 1, an anisotropic Nd--Fe--B system magnetic powder is produced by pulverizing an Nd--Fe--B system magnet that has been made anisotropic by hot working by a disk atomizing method.
　また、特許文献２には、鋳造合金を熱間加工した後に水素ガス雰囲気中で熱処理して水素を吸蔵させた後、真空中で脱水素を行なってから粉砕して磁石粉末を得る方法が記載されている。 Patent document 2 describes a method of hot working a cast alloy, heat-treating it in a hydrogen gas atmosphere to absorb hydrogen, dehydrogenating it in a vacuum, and pulverizing it to obtain a magnet powder. It is
　また、特許文献３には、鋳造インゴットを５００℃以上の温度で熱間加工することにより結晶粒が微細化されかつ結晶軸が特定の方向に配向した異方性の永久磁石の製造方法が記載されている。 Further, Patent Document 3 describes a method for manufacturing an anisotropic permanent magnet in which crystal grains are refined by hot working a cast ingot at a temperature of 500° C. or higher and the crystal axis is oriented in a specific direction. It is
米国特許第４８４２６５６号明細書U.S. Pat. No. 4,842,656 特開平４－１８８８０５号明細書Japanese Patent Application Laid-Open No. 4-188805 特開平８－２５０３１２号明細書Japanese Patent Application Laid-Open No. 8-250312
　従来から異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の高特性化方法は盛んに検討されてきた。しかしながら、そのほとんどはＨＤＤＲ法に関する検討であり、特許文献１のように異方性Ｎｄ－Ｆｅ－Ｂ系磁石を微粉化する報告は少ない。さらに特許文献１に記載されるような機械粉砕ではＮｄ－Ｆｅ－Ｂ組織への応力歪みによって磁気特性が低下するという課題がある。 　Conventionally, methods for improving the properties of anisotropic Nd-Fe-B magnetic powder have been actively studied. However, most of them are investigations on the HDDR method, and there are few reports on pulverization of anisotropic Nd--Fe--B magnets as in Patent Document 1. Furthermore, mechanical pulverization as described in Patent Document 1 poses a problem that magnetic properties are degraded due to stress strain on the Nd--Fe--B structure.
　特許文献２には、熱間加工された鋳造合金を水素雰囲気中で熱処理して水素を吸蔵させた後、真空中で脱水素を行って粉砕することが記載されている。しかしながら、実施例での水素吸蔵及び脱水素の温度は７５０℃以上であり、一般的にＨＤＤＲ法で用いられる温度で行なわれている。そして、得られた異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の磁気特性は、満足出来るものではなかった。 Patent Document 2 describes that a hot-worked cast alloy is heat-treated in a hydrogen atmosphere to absorb hydrogen, and then dehydrogenated in a vacuum and pulverized. However, the temperature for hydrogen absorption and dehydrogenation in the examples is 750° C. or higher, which is the temperature generally used in the HDDR method. The magnetic properties of the obtained anisotropic Nd--Fe--B magnetic powder were not satisfactory.
　特許文献３においては、熱間加工された鋳造インゴットを水素粉砕しているが、水素を吸蔵させた後の真空中で脱水素を行う条件は、室温で行なっている。そして、得られた異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の磁気特性は、満足出来るものではなかった。 In Patent Document 3, a hot-worked cast ingot is pulverized with hydrogen, but the conditions for dehydrogenation in a vacuum after absorbing hydrogen are at room temperature. The magnetic properties of the obtained anisotropic Nd--Fe--B magnetic powder were not satisfactory.
　本発明は優れたｉＨｃを有し、且つ微粒子である異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を製造することを目的とする。 An object of the present invention is to produce an anisotropic Nd--Fe--B magnetic powder that has an excellent iHc and is fine particles.
　上記課題を解決すべく、本発明者は鋭意検討した結果、Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石に対して、従来のＨＤＤＲ工程の水素吸蔵工程と脱水素工程で適切であった温度とは全く異なる温度範囲で処理を行なうことにより、意外にも優れた磁気特性を有する異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末が得られることを見出し、本発明を完成するに至った。 In order to solve the above-mentioned problems, the present inventors conducted extensive studies and found out what temperature was appropriate for the hydrogen absorption step and the dehydrogenation step of the conventional HDDR process for the Nd-Fe-B system hot-worked magnet. The inventors have found that anisotropic Nd--Fe--B magnetic powder having surprisingly excellent magnetic properties can be obtained by performing the treatment in a completely different temperature range, and have completed the present invention.
　本発明は、Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石に対して水素吸蔵工程と脱水素工程とを含む水素脆化処理を行うＮｄ－Ｆｅ－Ｂ系磁性粉末の製造方法であって、前記脱水素工程を１５０℃以上５００℃未満の温度で行うことを特徴とする異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法である（本発明の第１の要旨）。 The present invention relates to a method for producing an Nd--Fe--B system magnetic powder in which a hydrogen embrittlement treatment including a hydrogen absorption process and a dehydrogenation process is performed on an Nd--Fe--B system hot-worked magnet, wherein the dehydration A method for producing an anisotropic Nd--Fe--B magnetic powder characterized in that the pretreatment is carried out at a temperature of 150° C. or more and less than 500° C. (first gist of the present invention).
　また、本発明は前記水素吸蔵工程を水素雰囲気にて３０℃以上４００℃以下の温度で行うことが好ましい（本発明の第２の要旨）。 In addition, in the present invention, it is preferable that the hydrogen absorption step is performed at a temperature of 30°C or higher and 400°C or lower in a hydrogen atmosphere (second gist of the present invention).
　また、前記水素吸蔵工程における炉内圧力が１０１３ｈＰａ以上１０７０ｈＰａ以下であることが好ましい（本発明の第３の要旨）。 Further, it is preferable that the pressure in the furnace in the hydrogen absorbing step is 1013 hPa or more and 1070 hPa or less (the third gist of the present invention).
　また、前記脱水素工程において炉内圧力が１００Ｐａ以下となるまで真空排気を行うことが好ましい（本発明の第４の要旨）。 Further, in the dehydrogenation step, it is preferable to evacuate until the pressure in the furnace reaches 100 Pa or less (the fourth gist of the present invention).
　本発明によれば、熱間加工磁石を粉砕する際にＮｄ－Ｆｅ－Ｂ組織に歪みを与えることが少なく、優れた磁気特性を有し、且つ微粒子である異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を製造することができる。 According to the present invention, the anisotropic Nd-Fe-B system which has excellent magnetic properties and is fine particles with little strain on the Nd-Fe-B structure when the hot-worked magnet is pulverized Magnetic powders can be produced.
脱水素温度と本発明の異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末のｉＨｃの関係を示すグラフである。4 is a graph showing the relationship between the dehydrogenation temperature and the iHc of the anisotropic Nd--Fe--B magnetic powder of the present invention. 水素吸蔵温度と本発明の異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の粒径の関係を示すグラフである。4 is a graph showing the relationship between the hydrogen storage temperature and the particle size of the anisotropic Nd--Fe--B magnetic powder of the present invention.
　本発明の異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法は、Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石に水素脆化処理を行い、異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を得るものである。 In the method for producing an anisotropic Nd--Fe--B magnetic powder of the present invention, an Nd--Fe--B hot-worked magnet is subjected to hydrogen embrittlement treatment to obtain an anisotropic Nd--Fe--B magnetic powder. It is.
　Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石は、例えばメルトスピニング法によって作製されたリボンをダイアップセット法により熱間加工して得ることができる。この熱間加工によって得られた磁石は異方性を示す。 A Nd--Fe--B system hot-worked magnet can be obtained, for example, by hot-working a ribbon produced by a melt spinning method by a die upset method. A magnet obtained by this hot working exhibits anisotropy.
　Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石の組成はＮｄ２Ｆｅ１４Ｂを主相とし、添加元素Ａ（Ａ：Ｐｒ、Ｔｂ、Ｄｙ、Ｃｏ、Ｎｉ、Ｃｕ、Ａｌ、Ｚｒ、Ｇａ、Ｓｉ、Ｔｉ、Ｖ、Ｃｒ、Ｎｂ、Ｍｏ、Ｈｆ、Ｔａ、Ｗ）を含むことができる。 The composition of the Nd--Fe--B system hot-worked magnet is composed of Nd 2 Fe 14 B as the main phase and additive elements A (A: Pr, Tb, Dy, Co, Ni, Cu, Al, Zr, Ga, Si, Ti , V, Cr, Nb, Mo, Hf, Ta, W).
　本発明において、水素脆化処理とは、水素吸蔵工程と脱水素工程とを含む処理を指す。 In the present invention, the term "hydrogen embrittlement treatment" refers to a treatment that includes a hydrogen absorption process and a dehydrogenation process.
　水素吸蔵工程では、Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石に水素ガスを吸蔵させ、それに伴う体積膨張を利用してＮｄ－Ｆｅ－Ｂ系熱間加工磁石に多数のクラックを生じさせる。 In the hydrogen absorption process, the Nd--Fe--B system hot-worked magnet is made to absorb hydrogen gas, and the accompanying volume expansion is used to generate many cracks in the Nd--Fe--B system hot-worked magnet.
　水素吸蔵工程における処理温度は３０℃以上４００℃以下で行うことが望ましい。ここで処理温度を３０℃以上４００℃以下とした理由は３０℃未満及び４００℃を超える温度では水素吸蔵反応が進行しにくくなり、異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の粒子径が大きくなる為である。水素吸蔵温度はより好ましくは５０℃以上３００℃以下であり、更により好ましくは８０℃以上２３０℃以下である。 　The treatment temperature in the hydrogen absorption process is preferably 30°C or higher and 400°C or lower. The reason why the treatment temperature is set at 30° C. or higher and 400° C. or lower is that at temperatures below 30° C. and above 400° C., the hydrogen absorption reaction does not progress easily and the particle size of the anisotropic Nd—Fe—B magnetic powder becomes large. It is for the sake of becoming. The hydrogen absorption temperature is more preferably 50°C or higher and 300°C or lower, and still more preferably 80°C or higher and 230°C or lower.
　水素吸蔵工程は、水素雰囲気下で行う。水素吸蔵工程において炉内圧力は１０１３ｈＰａ以上になるように水素フローすることが望ましい。ここで炉内圧力を１０１３ｈＰａ以上とした理由は炉内に空気が混入する可能性を低くする為である。炉内圧力はより好ましくは１０１３ｈＰａ以上１０７０ｈＰａ以下である。ここで炉内圧力を１０７０ｈＰａ以下とした理由は炉内が過昇圧になり、水素が排気弁以外から漏れる危険性を低くする為である。 The hydrogen absorption process is performed under a hydrogen atmosphere. In the hydrogen absorption step, it is desirable to flow hydrogen so that the pressure inside the furnace is 1013 hPa or higher. The reason why the pressure in the furnace is set to 1013 hPa or more is to reduce the possibility of air entering the furnace. The furnace pressure is more preferably 1013 hPa or more and 1070 hPa or less. The reason why the pressure in the furnace is set to 1070 hPa or less is to reduce the risk that the pressure in the furnace becomes excessively high and hydrogen leaks from other than the exhaust valve.
　水素吸蔵工程における処理時間は１時間以上３時間３０分以下であることが望ましい。 　The treatment time in the hydrogen absorption process is preferably 1 hour or more and 3 hours and 30 minutes or less.
　脱水素工程では水素吸蔵工程でＮｄ－Ｆｅ－Ｂ系熱間加工磁石に吸蔵された水素を減圧下で脱離させる。 In the dehydrogenation process, the hydrogen absorbed in the Nd-Fe-B system hot-worked magnet in the hydrogen absorption process is desorbed under reduced pressure.
　なお、脱水素工程に先立って、炉内雰囲気を不活性ガスによって置換しておくことが好ましい。 It is preferable to replace the atmosphere in the furnace with an inert gas prior to the dehydrogenation step.
　脱水素工程における処理温度は１５０℃以上５００℃未満で行う。ここで処理温度を１５０℃以上とした理由は１５０℃未満では脱水素不足によってｉＨｃが低下する為である。また５００℃未満とした理由も５００℃以上の温度ではｉＨｃが低下する為であるが、その原因はＮｄ－Ｆｅ－Ｂ組織間の粒界相が変化する為と考えられる。脱水素温度はより好ましくは２００℃以上４００℃以下であり、更により好ましくは２７０℃以上３３０℃以下である。 The treatment temperature in the dehydrogenation process is 150°C or higher and lower than 500°C. The reason why the treatment temperature is set to 150° C. or higher is that if the temperature is lower than 150° C., the iHc decreases due to insufficient dehydrogenation. The reason why the temperature is less than 500° C. is that iHc decreases at a temperature of 500° C. or higher, and the reason for this is thought to be that the grain boundary phase between the Nd—Fe—B structures changes. The dehydrogenation temperature is more preferably 200° C. or higher and 400° C. or lower, and still more preferably 270° C. or higher and 330° C. or lower.
　脱水素工程においては、炉内圧力が１００Ｐａ以下となるまで真空排気することが望ましい。炉内圧力が１００Ｐａ以上の時に排気を終了した場合、Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石からの水素の脱離が不十分となりｉＨｃが低下する為である。脱水素工程の炉内圧力はより好ましくは１０Ｐａ以下であり、更に好ましくは１Ｐａ以下である。 In the dehydrogenation process, it is desirable to evacuate the furnace until the pressure inside the furnace reaches 100 Pa or less. This is because if the exhaust is terminated when the pressure in the furnace is 100 Pa or more, desorption of hydrogen from the Nd--Fe--B system hot-worked magnet becomes insufficient and iHc decreases. The furnace pressure in the dehydrogenation step is more preferably 10 Pa or less, and still more preferably 1 Pa or less.
　脱水素工程の処理時間は１時間以上１８時間以内であることが望ましい。 It is desirable that the treatment time of the dehydrogenation process is 1 hour or more and 18 hours or less.
　脱水素工程後、炉内を不活性ガスで復圧して炉内を室温まで冷却し、水素脆化処理を施された熱間加工磁石を解砕することによって、異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を得ることができる。 After the dehydrogenation step, the pressure inside the furnace is restored with an inert gas, the inside of the furnace is cooled to room temperature, and the hot-worked magnet subjected to the hydrogen embrittlement treatment is cracked to obtain an anisotropic Nd--Fe--B magnet. A system magnetic powder can be obtained.
　異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の粒径は４００μｍ以下が好ましい。ここで粒径を４００μｍ以下とした理由はボンド磁石の製造において成形を容易にする為である。粒径はより好ましくは２００μｍ以下であり、更に好ましくは１５０μｍ以下である。 The particle size of the anisotropic Nd--Fe--B magnetic powder is preferably 400 μm or less. The reason why the grain size is set to 400 μm or less is to facilitate molding in the production of bonded magnets. The particle size is more preferably 200 μm or less, still more preferably 150 μm or less.
　異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の保磁力（ｉＨｃ）は１５ｋＯｅ以上が好ましい。ここでｉＨｃを１５ｋＯｅ以上とした理由は耐熱性を有したボンド磁石を製造する為である。ｉＨｃはより好ましくは１８ｋＯｅ以上である。 The coercive force (iHc) of the anisotropic Nd--Fe--B magnetic powder is preferably 15 kOe or more. The reason why iHc is set to 15 kOe or more is to manufacture a heat-resistant bonded magnet. iHc is more preferably 18 kOe or more.
　以下に、本発明の実施例と比較例を示す。 Examples and comparative examples of the present invention are shown below.
　本発明における異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の磁気特性として、残留磁束密度（Ｂｒ）、保磁力（ｉＨｃ）を振動試料型磁束計（ＶＳＭ：玉川製作所製ＴＭ－ＶＳＭ２１３０ＨＲＨＬ型）にて測定した。 As the magnetic properties of the anisotropic Nd--Fe--B magnetic powder of the present invention, residual magnetic flux density (Br) and coercive force (iHc) were measured with a vibrating sample magnetometer (VSM: TM-VSM2130HRHL model manufactured by Tamagawa Seisakusho). It was measured.
　本発明における異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の粒径は、メジアン径（ｄ５０）を測定した。メジアン径（ｄ５０）の分析にはレーザーマイクロサイザー（セイシン企業製ＭＳ－２０００ｅ）を用いた。 For the particle size of the anisotropic Nd--Fe--B magnetic powder in the present invention, the median diameter (d50) was measured. A laser microsizer (MS-2000e manufactured by Seishin Enterprise Co., Ltd.) was used to analyze the median diameter (d50).
　実施例１：
（水素吸蔵工程）
　Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石をＡｒ雰囲気の熱処理炉内に投入し、熱処理炉内を２００℃まで昇温した。熱処理炉内の温度が２００℃に達したところで、雰囲気をＡｒからＨ２に置換し、Ｈ２を流入させながら２００℃で７０分間熱処理をする水素吸蔵工程を実施した。熱処理炉内の圧力は１０６０ｈＰａであった。 Example 1:
(Hydrogen absorption process)
The Nd--Fe--B system hot-worked magnet was put into a heat treatment furnace in an Ar atmosphere, and the inside of the heat treatment furnace was heated to 200.degree. When the temperature in the heat treatment furnace reached 200° C., the atmosphere was replaced from Ar to H 2 , and a hydrogen absorption step was performed in which heat treatment was performed at 200° C. for 70 minutes while introducing H 2 . The pressure inside the heat treatment furnace was 1060 hPa.
（脱水素工程）
　水素吸蔵工程完了後、熱処理炉内の雰囲気をＡｒに置換した。熱処理炉内の雰囲気がＡｒに置換された後、熱処理炉内を２００℃とし、炉内を５．０×１０－３Ｐａまで真空排気する脱水素工程を実施した。脱水素工程の時間は１０８０分間であった。その後、熱処理炉内をＡｒで復圧して炉内を室温まで冷却した。熱処理炉の冷却が完了した後、解砕を行って、熱間加工磁石が粉砕された磁性粉末を得た。 (Dehydrogenation step)
After the hydrogen absorption step was completed, the atmosphere in the heat treatment furnace was replaced with Ar. After the atmosphere in the heat treatment furnace was replaced with Ar, the inside of the heat treatment furnace was set to 200° C., and a dehydrogenation step was performed in which the inside of the furnace was evacuated to 5.0×10 −3 Pa. The duration of the dehydrogenation step was 1080 minutes. Thereafter, the pressure inside the heat treatment furnace was restored with Ar, and the inside of the furnace was cooled to room temperature. After the cooling of the heat treatment furnace was completed, pulverization was carried out to obtain a magnetic powder in which the hot-worked magnet was pulverized.
　実施例２：
　水素吸蔵工程の温度と処理時間がそれぞれ２００℃、６０分間、及び脱水素工程の温度と処理時間が３００℃、１４５分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Example 2:
Magnetic powder was obtained by carrying out the treatment in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 200° C. for 60 minutes, and the temperature and treatment time in the dehydrogenation step were 300° C. and 145 minutes, respectively. rice field.
　実施例３：
　水素吸蔵工程の温度と処理時間がそれぞれ１５０℃、８０分間、及び脱水素工程の温度と処理時間が３００℃、２００分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Example 3:
Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150°C and 80 minutes, respectively, and the temperature and treatment time in the dehydrogenation step were 300°C and 200 minutes, respectively. rice field.
　実施例４：
　水素吸蔵工程の温度と処理時間がそれぞれ１５０℃、１７０分間、及び脱水素工程の温度と処理時間が４００℃、２００分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Example 4:
Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150°C and 170 minutes, respectively, and the temperature and treatment time in the dehydrogenation step were 400°C and 200 minutes, respectively. rice field.
　実施例５：
　水素吸蔵工程の温度と処理時間がそれぞれ１５０℃、１７０分間、及び脱水素工程の温度と処理時間が４５０℃、２００分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Example 5:
Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150°C and 170 minutes, respectively, and the temperature and treatment time in the dehydrogenation step were 450°C and 200 minutes, respectively. rice field.
　実施例６：
　水素吸蔵工程の温度と処理時間がそれぞれ１１０℃、１７０分間、及び脱水素工程の温度と処理時間が３００℃、１０８０分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Example 6:
Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 110°C and 170 minutes respectively, and the temperature and treatment time in the dehydrogenation step were 300°C and 1080 minutes. rice field.
　実施例７：
　水素吸蔵工程の温度と処理時間がそれぞれ３２０℃、６０分間、及び脱水素工程の温度と処理時間が３００℃、５５分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Example 7:
Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 320° C. for 60 minutes, and the temperature and treatment time in the dehydrogenation step were 300° C. and 55 minutes, respectively. rice field.
　比較例１：
　水素吸蔵工程の温度と処理時間がそれぞれ１００℃、７０分間、及び脱水素工程の温度と処理時間が１００℃、１０５０分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Comparative Example 1:
Magnetic powder was obtained by carrying out the treatment in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 100° C. for 70 minutes, and the temperature and treatment time in the dehydrogenation step were 100° C. and 1050 minutes. rice field.
　比較例２：
　水素吸蔵工程の温度と処理時間がそれぞれ１５０℃、８０分間、及び脱水素工程の温度と処理時間が５５０℃、２００分間とした以外は実施例１と同様にして処理を行って磁性粉末を得た。 Comparative Example 2:
Magnetic powder was obtained in the same manner as in Example 1, except that the temperature and treatment time in the hydrogen absorption step were 150° C. for 80 minutes, and the temperature and treatment time in the dehydrogenation step were 550° C. and 200 minutes, respectively. rice field.
　実施例１～７及び比較例１～２の磁性粉末の製造条件と磁気特性及び粒径（メジアン径）を表１に示す。 Table 1 shows the manufacturing conditions, magnetic properties, and particle size (median diameter) of the magnetic powders of Examples 1 to 7 and Comparative Examples 1 and 2.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　実施例１～７で得られた磁性粉末に比べ、比較例１の脱水素温度が１００℃で製造された磁性粉末のｉＨｃは低かった。また、比較例２の脱水素温度が５５０℃で製造された磁性粉末のｉＨｃは、実施例３と比較して低かった。図１に示すように、これらの例の中でｉＨｃは３００℃付近で最大値を示す傾向が見られた。また、いずれの例においても、水素脆化処理によって微粒子の磁性粉末が得られたが、図２に示すように、これらの実施例の中では水素吸蔵温度が低下するに従って磁性粉末がより微粒子化される傾向が見られた。 　Compared to the magnetic powders obtained in Examples 1 to 7, iHc of the magnetic powder produced at a dehydrogenation temperature of 100°C in Comparative Example 1 was lower. Further, the iHc of the magnetic powder produced at a dehydrogenation temperature of 550° C. in Comparative Example 2 was lower than that in Example 3. As shown in FIG. 1, iHc tended to show a maximum value around 300° C. in these examples. In all of the examples, fine magnetic powder was obtained by the hydrogen embrittlement treatment, but as shown in FIG. There was a tendency to
　本発明は、優れた磁気特性を有し、且つ微粒子である異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末を製造することができるため、これを用いたボンド磁石の高性能化に有用である。 Since the present invention can produce anisotropic Nd--Fe--B magnetic powder that has excellent magnetic properties and is fine particles, it is useful for improving the performance of bonded magnets using this.

Claims (4)

  1. 　Ｎｄ－Ｆｅ－Ｂ系熱間加工磁石に対して水素吸蔵工程と脱水素工程とを含む水素脆化処理を行うＮｄ－Ｆｅ－Ｂ系磁性粉末の製造方法であって、前記脱水素工程を１５０℃以上５００℃未満の温度で行うことを特徴とする異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法。 A method for producing an Nd--Fe--B magnetic powder by subjecting an Nd--Fe--B system hot-worked magnet to a hydrogen embrittlement treatment including a hydrogen absorption step and a dehydrogenation step, wherein the dehydrogenation step is performed by 150 A method for producing an anisotropic Nd--Fe--B system magnetic powder characterized in that the process is carried out at a temperature of at least 500.degree.
  2. 　前記水素吸蔵工程を水素雰囲気にて３０℃以上４００℃以下の温度で行うことを特徴とする請求項１に記載の異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法。 The method for producing an anisotropic Nd--Fe--B magnetic powder according to claim 1, characterized in that the hydrogen absorbing step is carried out in a hydrogen atmosphere at a temperature of 30°C or higher and 400°C or lower.
  3. 　前記水素吸蔵工程における炉内圧力が１０１３ｈＰａ以上１０７０ｈＰａ以下であることを特徴とする請求項１または２に記載の異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法。 The method for producing an anisotropic Nd--Fe--B magnetic powder according to claim 1 or 2, characterized in that the pressure in the furnace in the hydrogen absorbing step is 1013 hPa or more and 1070 hPa or less.
  4. 　前記脱水素工程において炉内圧力が１００Ｐａ以下となるまで真空排気を行うことを特徴とする請求項１または２に記載の異方性Ｎｄ－Ｆｅ－Ｂ系磁性粉末の製造方法。

          3. The method for producing an anisotropic Nd--Fe--B magnetic powder according to claim 1, wherein in said dehydrogenation step, the furnace is evacuated to a pressure of 100 Pa or less.
PCT/JP2022/044508 2021-12-07 2022-12-02 PRODUCTION METHOD FOR ANISOTROPIC Nd-Fe-B MAGNETIC POWDER WO2023106221A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN202280069088.5A CN118120033A (en) 2021-12-07 2022-12-02 Method for producing anisotropic Nd-Fe-B magnetic powder
JP2023566283A JPWO2023106221A1 (en) 2021-12-07 2022-12-02

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2021-198745 2021-12-07
JP2021198745 2021-12-07

Publications (1)

Publication Number Publication Date
WO2023106221A1 true WO2023106221A1 (en) 2023-06-15

Family

ID=86730403

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/044508 WO2023106221A1 (en) 2021-12-07 2022-12-02 PRODUCTION METHOD FOR ANISOTROPIC Nd-Fe-B MAGNETIC POWDER

Country Status (3)

Country Link
JP (1) JPWO2023106221A1 (en)
CN (1) CN118120033A (en)
WO (1) WO2023106221A1 (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004137582A (en) * 2002-10-21 2004-05-13 Sumitomo Special Metals Co Ltd Sintered rare earth magnet and its production method

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004137582A (en) * 2002-10-21 2004-05-13 Sumitomo Special Metals Co Ltd Sintered rare earth magnet and its production method

Also Published As

Publication number Publication date
JPWO2023106221A1 (en) 2023-06-15
CN118120033A (en) 2024-05-31

Similar Documents

Publication Publication Date Title
JP6366666B2 (en) Method for producing sintered Nd-Fe-B magnetic body containing no heavy rare earth element
JP6037128B2 (en) R-T-B rare earth magnet powder, method for producing R-T-B rare earth magnet powder, and bonded magnet
CN109102976B (en) Method for improving magnetic property of rare earth neodymium iron boron
JPH01704A (en) Rare earth-iron permanent magnet
JP2018157197A (en) Highly thermally stable rare earth permanent magnet material, method for manufacturing the same, and magnet including the same
JP5708242B2 (en) Rare earth magnet manufacturing method
CN110895985A (en) Mixed rare earth sintered neodymium-iron-boron permanent magnet and preparation method thereof
JPH0366105A (en) Rare earth anisotropic powder and magnet, and manufacture thereof
CN114334416B (en) Method for preparing high-performance neodymium-iron-boron magnet by solid-liquid phase separation diffusion process
JPH01257308A (en) Magnet for voice coil motor
KR102454771B1 (en) A Preparation Method of a Rare Earth Anisotropic Bonded Magnetic Powder
JP5742733B2 (en) Rare earth magnet manufacturing method
WO2023106221A1 (en) PRODUCTION METHOD FOR ANISOTROPIC Nd-Fe-B MAGNETIC POWDER
JP2015128118A (en) Method of manufacturing rare-earth magnet
JPH1070023A (en) Permanent magnet and manufacture thereof
CN110299235B (en) Method for producing R-T-B sintered magnet
CN113838658A (en) Preparation method of iron-silicon magnetic powder core
JP2002075715A (en) Anisotropic bulk exchange spring magnet and manufacturing method thereof
JP2018060931A (en) Method for producing r-t-b based magnet
JP6447804B2 (en) Method for manufacturing magnet compact
JP2016502260A (en) Among the HDDR methods, a hydrogen release and recombination stage control method, a method for producing a rare earth-iron-boron rare earth magnetic powder including a hydrogen release and recombination stage, and a rare earth-iron-boron rare earth magnetic powder produced thereby
US10546688B2 (en) Method for producing rare-earth magnet
CN109148133B (en) Rare earth permanent magnet and preparation method thereof
JPH04143221A (en) Production of permanent magnet
CN113903590A (en) Resource-saving 48H neodymium-iron-boron permanent magnet material preparation process

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22904150

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 202280069088.5

Country of ref document: CN

ENP Entry into the national phase

Ref document number: 2023566283

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE