METHOD FOR MANUFACTURING RARE EARTH MAGNET

• Main Authors: ICHIKIZAKI DAISUKE, TAKAHASHI TAKAAKI, SAKUMA DAISUKE, KOMORI KENSUKE
• Format: Patent
• Language: English; Japanese
• Published: 12.05.2016
• 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 method for manufacturing a rare earth magnet, which enables the manufacturing of a rare earth magnet superior in magnetic property even if magnetic powder manufactured by a liquid quenching technique includes both of nanocrystal and amorphous.SOLUTION: A method for manufacturing a rare earth magnet comprises: a first step where a molten metal expressed by the compositional formula, (Rl)(Rh)TBM(where Rl represents at least one light rare earth element including Y; Rh represents at least one heavy rare earth element of Dy and Tb; T represents at least one transition metal of Fe, Ni and Co; B represents boron; M represents at least one kind of Ga, Al and Cu; 27≤x≤44, 0≤y≤10, z=100-x-y-s-t, 0.75≤s≤3.4 and 0≤t≤3, provided that the numerical values are represented in mass%) is quenched, thereby producing magnetic powder MF having nanocrystal magnetic powder and amorphous magnetic powder mixed therein, and an average crystal grain diameter of 500 nm or less; and a second step where the magnetic powder MF is sintered to produce a sintered compact S, and a hot plastic working is performed on the sintered compact S, thereby manufacturing the rare earth magnet C.SELECTED DRAWING: Figure 1 【課題】液体急冷法にて製作される磁性粉末がナノ結晶質と非晶質の双方を含んでいても、磁気特性に優れた希土類磁石を製造することのできる希土類磁石の製造方法を提供する。【解決手段】(Rl)x(Rh)yTzBsMt(RlはYを含む1種以上の軽希土類元素、RhはDy、Tbの少なくとも1種からなる重希土類元素、TはFe、Ni、Coの少なくとも1種以上を含む遷移金属、Bはホウ素、MはGa、Al、Cuの少なくとも1種類以上で、27≦x≦44、0≦y≦10、z=100-x-y-s-t、0.75≦s≦3.4、0≦t≦3で、いずれも質量%)の組成式で表される金属溶湯を急冷し、平均結晶粒径が500nm以下のナノ結晶質の磁性粉末と非晶質の磁性粉末が混在する磁性粉末ＭＦを製作する第１のステップ、磁性粉末ＭＦを焼結して焼結体Ｓを製作し、焼結体Ｓに熱間塑性加工を施して希土類磁石Ｃを製造する第２のステップからなる希土類磁石の製造方法である。【選択図】図１