Method for manufacturing R-T-B system rare earth permanent magnet

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 R2T14B phase (wherein R represents one or more rare earth elements, providing that the rare earth elements include Y), and T represents one or more transition metal elements essentially containing Fe, or Fe and Co, and a grain boundary phase containing a higher amount of R than said main phase,
• wherein a product that is rich in Zr exists in said R2T14B phase,
• said manufacturing method comprising the steps of:
• preparing an R-T-B alloy containing as a main component said R2T14B phase and also containing the whole amount of Zr, and an R-T alloy containing R and T as main components, wherein the amount of R is higher than that of said R-T-B alloy;
• 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 R2T14B phase;
• and
• 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.