RECYCLING METHOD OF RARE EARTH-TRANSITION METAL SCRAP, MAGNETIC SUBSTANCE POWDER FOR WAVE ABSORPTIO

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PROBLEM TO BE SOLVED : To provide a method for inexpensively and effectively recycling a rare earth-transition metal scrap obtained through production or disposal of rare-earth magnets or hydrogen-storing alloys, beyond the boundaries of its regeneration into a similar material. SOLUTION : The rare earth-transition metal scrap is heat-treated in an oxygen-containing atmosphere. Here, the scrap in dudes at least one chosen from defective products or unnecessary residues not composing products, which are produced during the production of rare-earth magnets or hydrogen-storing alloys, and wastes recovered from used products onto which rare-earth magnets or hydrogen-storing alloys have been mounted. Based on this oxidation reaction, a reaction treatment for disproportion is performed, whereby a transition metal-based magnetic fine particle having an average particle size of ≤500 nm and a higher content of transition metal than that in a rare earth-transition metal-based intermetallic compound essentially composing the scrap and a rare-earth oxide particle having an average particle size of ≤500 nm and essentially comprising excessive rare-earth metals are liberated and produced through decomposition. In this way, the scrap is regenerated as a magnetic substance powder for wave absorption comprising a composite of the transition metal-based metal fine particle and the rare-earth oxide.