To provide a dust core excellent in specific resistance and strength.
The dust core includes soft magnetic particles, and a grain boundary phase formed among the soft magnetic particles. The grain boundary phase has a such composite dispersion system in which fine particles containing a high temperature softening material (nano particles of silica and aluminum) which contain a second inorganic oxide having a softening point higher than an annealing temperature are dispersed in the matrix containing a low temperature softening material (low-melting point glass particles) that contains a first inorganic oxide having a softening point lower than the annealing temperature of the soft magnetic particle. Since the grain boundary phase has the composite dispersion system like this, the soft magnetic particles are strongly coupled by the low temperature softening material and a predetermined interval is held by the high temperature softening material, to assure insulation property. Thus the dust core in which both a high specific resistance and a high strength are provided in a high dimension is provided.
TANI MASAAKI
HATTORI TAKESHI
OISHI YUSUKE
OKAMOTO DAISUKE
TOYOTA MOTOR CORP
| JP2010236018A | 2010-10-21 | |||
| JPH11158502A | 1999-06-15 |
Sansui International Patent Office