| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a means for sufficiently suppressing an eddy-current loss and preventing the lowering of a magnet characteristic caused by an insulating material, in a permanent magnet obtained by densifying permanent magnet powder with a coating layer comprising the insulating material, formed on surfaces of particles thereof. <P>SOLUTION: This invention relates to the permanent magnet obtained by densifying permanent magnet powder with a coating layer comprising the insulating material, formed on surfaces of particles thereof, wherein a relation H≥23000×d<SP>-1</SP>is satisfied wherein H (= t×ρ<SB>r</SB>÷ρ<SB>m</SB>) is defined as a value resulting from dividing the product of a thickness t(m) of the covering layer comprising the insulating material and a volume resistivity ρ<SB>r</SB>(Ωm) of the insulating material by a volume resistivity ρ<SB>m</SB>(Ωm) of the permanent magnet powder and d (mm) is a grain size of the permanent magnet powder. <P>COPYRIGHT: (C)2011,JPO&INPIT |
