Tohoku University

Toda Kogyo Corporation

Yasunobu Ogata

Migaku Takahashi

Naoya Kobayashi

Tomoyuki Ogawa

Chammika Ruwan Polwatta Gallage

Kaori Kohara

Ferromagnetic particles including an FeNcompound phase in an amount of not less than 80% as measured by M&#xf6;ssbauer spectrum and each having an outer shell in which FeO is present in the form of a film having a thickness of not more than 5 nm. Ferromagnetic particles may be made by subjecting iron oxide or iron oxyhydroxide having an average major axis diameter of 40 to 5000 nm and an aspect ratio (major axis diameter/minor axis diameter) of 1 to 200 as a starting material to dispersing treatment to prepare aggregated particles; subjecting the iron compound particles passed through a mesh to hydrogen reducing treatment at a temperature of 160 to 420&#xb0; C.; and then subjecting the resulting particles to nitridation treatment at a temperature of 130 to 170&#xb0; C.

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Sendai, Japan

Yasunobu Ogata