PURPOSE: To obtain a magnet particularly having good temperature characteristics by sintering an alloy composed mainly of Fe and containing a rare earth element R containing Y, Co, B and Ga, thereby producing a permanent magnet which is composed mainly of a ferromagnetic Fe-rich phase of the tetragonal system and containing a non-magnetic Laves phase.
CONSTITUTION: A given amount of Ga is added to a composition of the R-B-Co- Fe system to develop a non-magnetic Laves phase. Its wt.% composition is such that R is 10W40%, B is 0.1W8%, Co is 1W30%, Ga is 0.1W1%, and the remainder is substantially Fe. This alloy is ground to an average particle diameter of 2W10μm, oriented by applying a magnetic field when pressing, subsequently sintered in Ar of about 1100°C, and then aged. If the proportion of the Laves phase is 2W10vol.%, B is 0.8W0.95wt.% and 90wt.% or less of Ga is substituted by Al, then a permanent magnet is obtained which has a higher Curie temperature an paticularly has good temperature characteristics.
TSUTAI AKIHIKO
SAKAI ISAO
INOMATA KOICHIRO
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