RARE EARTH-TRANSITION METAL-NITROGEN BASED MAGNETIC POWDER AND METHOD FOR PRODUCING THE SAME

• Main Authors: HOTTA HITOSHI, NAGANAMI TAKESHI
• Format: Patent
• Language: English; Japanese
• Published: 28.05.2015
• Subjects: ALLOYS; BASIC ELECTRIC ELEMENTS; CASTING; CHEMISTRY; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; INDUCTANCES; MAGNETS; MAKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; METALLURGY; PERFORMING OPERATIONS; POWDER METALLURGY; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WORKING METALLIC POWDER

PROBLEM TO BE SOLVED: To provide a rare earth-transition metal-nitrogen based magnet powder excellent in surface stability having especially high coercive force in which the ratio of a particle size of 1 μm or less is decreased without excessively pulverizing a reduction product after reduction diffusion.SOLUTION: There is provided a rare earth-transition metal-nitrogen based magnet powder produced by a reduction diffusion method. The magnet powder contains at least one element selected from Ti, Zr and Al in an outer peripheral part of a rare earth-iron-alloy and the ratio of a particle size having an average particle diameter (D50) of more than 4 μm and 10 μm or less is less than 10%. 【課題】還元拡散後の還元生成物に過度の粉砕を行わず、１μｍ以下の粒度の割合が減少し、特に高い保磁力を有する表面安定性に優れた希土類−遷移金属−窒素系磁石粉末とその安価な製造方法の提供。【解決手段】還元拡散法で製造される希土類−遷移金属−窒素系磁石粉末であって、希土類−鉄合金の外周部にＴｉ、Ｚｒ、Ａｌから選択される少なくとも一種の元素を含み、平均粒径（Ｄ５０）が４μｍを超え１０μｍ以下で、１μｍ以下の粒度の割合が１０％未満であることを特徴とする希土類−遷移金属−窒素系磁石粉末などにより提供する。【選択図】図１