Production of rare earth magnets, rare earth magnet material and the alloy powder

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PROBLEM TO BE SOLVED : To provide a method for manufacturing rare-earth magnet by which the rare earth magnet of high magnetic characteristic is supplied easily and stably and an end material amount generated in the case of working a magnet is reduced, by improving the oxidation and yield of R component so as to expand a sintering temperature area in a method using a single alloy, and to provide alloy and powder useful for the method. SOLUTION : The method for manufacturing comprises a process for preparing a material alloy (A) and a raw material (B). The material alloy (A) has the specific composition of R-B-M. In the material alloy (A), an R2Fe14B phase is a main phase and is 77 vol.%, an R-rich phase is 15 to 23 vol.%, 90 vol.% of the R2Fe14B phase consists of crystal grains of a specific grain diameter, and the axial lattice constant of the R2Fe14B phase is larger than that in a balanced state by 0.3 to 1%. The material alloy (B) has the specific composition of R-B-M. In the material alloy (B), a main phase R2Fe14B is 85 vol.%, and an R-rich phase is not larger than 15 vol.%. The method also comprises a process of crushing the alloys (A) and (B), a process of molding crushed powder, a process of sintering the molded matter, and a heat treatment process for treating a sintered matter with heat. COPYRIGHT : (C)2004, JPO&NCIPI