PURPOSE: To realize a high performance magnet by making an R2TM17 series bond magnet (R denotes rare earth elements and TM denotes transition metals) high in Br compsn.
CONSTITUTION: In an alloy for an R2TM17-based bond magnet, the average cooling rate from the molten metal to the m.p. is regulated to 100 to <10000°C/sec and the Raynoid's number of the flow of molten metal poured and sprayed from a molten metal pouring nozzle or a tundish is regulated to ≤4000, by that the average of the secondary arm distance of dendrite formed at the time of casting is regulated to ≤10μm as well as the volume of the part in which the angle at which its growing direction forms the perpendicular of the cooled face of the alloy is regulated to ≤30° is regulated to ≥90% of the total volume. In this way, the high-iron compsn. and rate earth substituted compsn. which are hardly homogenized can be practicable, and the energy product of a bond magnet can be improved.
ISHIBASHI TOSHIYUKI
KITAZAWA ATSUNORI
AKIOKA KOJI
