PROCESS FOR PRODUCTION OF RARE EARTH ALLOY POWDER, ANISOTROPIC BONDED MAGNET, AND SINTERED MAGNET

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A process for producing a rare earth alloy powder by a hydrogenation-decomposition/dehydrogenation-recombination method, which comprises (a) a step of hydrogenating/decomposing a raw material alloy containing a rare earth element to produce a decomposition product, (b) a step of releasing hydrogen from the decomposition product to reduce the hydrogen concentration in the decomposition product, and (c) a step of further releasing hydrogen from the decomposition product at a lower release rate than the hydrogen release rate employed in step (b) to produce the rare earth alloy powder, and which is characterized in that an R2Fe14B phase (wherein R represents a rare earth element) covers a rare earth hydride phase in the cross section of the decomposition product, and step (b) advances to step (c) at the time point at which the ratio of the area of the R2Fe14B phase to the total area of the cross section becomes 25-55%.