To stably make producable of high characteristic rare-earth-metal magnetic alloy exceeding 400 KJ/m3 in a mass-production level.
A method for producing a rare-earth-metal alloy thin sheet is performed as the followings, that is, when the alloy thin sheet is obtained by rapidly cooling with a cooling roll to molten alloy having the composition composed of 26.8-32.0% R (rare-earth-metal elements containing Y), 0.3-1.5% B, 0.005-1.2% C, 0-4.0% additional element M (Ga, Zr, Nb, Hf, Ta, W, Mo, Al, Si, V, Cr, Ti, Cu, Ag, Mn, Ni, Ge, Sn, Bi, Pb, Zn) and the balance T (Fe and/or Co) with inevitable impurities, the cooling roll is used to one, in which the surface layer in contact with the molten alloy has 10-30 mm thickness and 500-1000 mm the outer diameter formed of copper or a copper alloy having ≥200 W/m°C thermal conductivity, and the molten alloy is rapidly cooled by rotating, the cooling roll at 20-120 rotation/min speed while water-cooling this inner part.
HIROTA KOICHI
SATO KOJI
MINOWA TAKEHISA
Saori Shigematsu
Katsunari Kobayashi
Takeshi Ishikawa
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