Patent ID: 7255752
Filing Date: 2007-08-14
Classification: H01F

Abstract:
1. A method for manufacturing an R-T-B system rare earth permanent magnet comprising a sintered body having 0.03% to 0.25% by weight of Zr, wherein said sintered body comprises a main phase consisting of an R wherein a product that is rich in Zr exists in said R said manufacturing method comprising the steps of: preparing an R-T-B alloy containing as a main component said R obtaining a mixture of a powder of said R-T-B alloy and a powder of said R-T alloy; preparing a compacted body with a certain form from said mixture; and sintering said compacted body, wherein, in said sintering step, said product is generated in said R wherein said R-T-B alloy is prepared by the strip casting method under the condition that the peripheral velocity of a chill roll is 1.0 to 1.8 m/s.