METHOD FOR REGENERATING SCRAP MAGNETS

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In an example of a conventional method, the regeneration of sintered magnets is achieved by means of a number of processes involving solvent extraction etc. As a result, productivity is poor and, since a number of solvents such as hydrofluoric acid and the like are used, the cost is high. The present method includes the following steps : a step in which scrap iron - boron - rare earth sintered magnets are recovered and pulverized and recovered raw material powder is obtained; a step in which a sintered compact is obtained from said recovered raw material powder using a powder metallurgical method and a step in which said sintered compact is arranged in a treatment chamber and heated, and a material for metal vaporization purposes containing at least one of Dy and Tb which is arranged in the same or another treatment chamber is vaporized, and vaporized metal atoms are deposited on the sintered magnet surface while the amount of said atoms which are being supplied is controlled, and the deposited metal atoms are diffused into the crystal grain boundaries and/or crystal grain boundary phase of the sintered compact.