| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rare earth-iron-boron based magnet which includes a low coercive force and a high squareness ratio suitable as the magnet for motor, and to provide a method of manufacturing the same. <P>SOLUTION: A permanent magnet includes a predetermined composition and a squareness ratio of 85% or more which is represented by the ratio of the remanent magnetization to the magnetization in a magnetic field where the coercive force is 0.5-5 kOe and 10 kOe or more. Preferably, the general formula (R1<SB>1-x-y</SB>R2<SB>x</SB>R3<SB>y</SB>)<SB>a</SB>Fe<SB>b</SB>Co<SB>c</SB>B<SB>d</SB>M<SB>e</SB>X<SB>f</SB>C<SB>g</SB>satisfies the following conditions, R1: at least one selected from Nd or Pr, R2: at least one selected from Sm, La or Ce, R3: at least one selected from Tb or Dy, M: at least one selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Ni, or Cu, and X: at least one selected from Ga, Si or Al. <P>COPYRIGHT: (C)2010,JPO&INPIT |
