| 摘要 |
<P>PROBLEM TO BE SOLVED: To further improve magnetic characteristics while fining spinel type ferrimagnetic-substance grains, and to provide magnetic grain powder having a particularly large coercive force. <P>SOLUTION: In spinel type ferrimagnetic fine-grain powder, the value of the ratio (n) (Fe/(Co+Ni+M)) of Fe to (Co+Ni+M) is 2.2<n<3.0, and 0.65<x<0.9, 0.08<y<0.3, 0.008<z<0.025 and x+y+z=1 hold, in a composition formula (CoO)<SB>x</SB>(NiO)<SB>y-z</SB>(M<SB>2</SB>O<SB>3</SB>)<SB>0.5z</SB>-n/2Fe<SB>2</SB>O<SB>3</SB>(M represents Cr or Y). <P>COPYRIGHT: (C)2007,JPO&INPIT |
