Method for manufacturing permanent magnet

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PURPOSE : To improve magnetic characteristics of an R-T-B sintered magnet and to manufacture such a magnet at low cost. CONSTITUTION : When a permanent magnet containing R (rare earth element) T (Fe or Fe and Co) and B as main ingredients and R2T14B of a main phase is manufactured by molding and sintering a mixture of powder of base alloy for the main phase and base alloy for a grain boundary phase, as the alloy for the main phase, alloy containing R2T14B columnar crystal grains having a mean grain size of 3-50mum and R-rich phase (crystal grain boundary) and containing 26-32wt.% of R is used, and as the alloy for the grain boundary phase, crystalline alloy containing 32-60wt.% of R and the residue of substantially Co or Co and Fe is used. The mean crystalline grain size of the alloy for the grain boundary phase is preferably 0.1-20mum by a quenching method such as a single roll method, etc.