| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce the composition distribution occurring among the individual particles of FePt nanoparticles and to improve magnetic properties. <P>SOLUTION: The metal magnetic powder has a composition which contains, when T represents either or both of Fe and Co and M represents either or both of Pt and Pd, T and M in a composition ratio where the value of X in the formula: [T<SB>X</SB>M<SB>1-X</SB>] ranges from 0.3 to 0.7 and in which the amount of metallic elements other than T and M becomes ≤30 atomic% (including 0%) in an atomic percentage to (T+M) and the balance is composed of inevitable impurities in manufacturing. In this metal magnetic powder, the average particle diameter (D<SB>TEM</SB>) measured by TEM (transmission electron microscope) observation is ≤50 nm, and further, the number of particles satisfying inequality 0.90X<SB>av</SB>≤X<SB>1</SB>, X<SB>2</SB>, ... X<SB>100</SB>≤1.10X<SB>av</SB>is ≥95 out of 100 and also inequality (standard deviation σ of X<SB>1</SB>, X<SB>2</SB>, ... X<SB>100</SB>)≤20% is satisfied. In the above formulas, X<SB>av</SB>stands for a value actually measured as powder with respect to the value of X in the composition formula: [T<SB>X</SB>M<SB>1-X</SB>]; and [X<SB>1</SB>, X<SB>2</SB>, ... X<SB>100</SB>] stands for respective values of the individual X measured with respect to 100 particles arbitrarily selected in a state where ≥1,000 particles are present in the measurement visual field, at the TEM-EDX (energy dispersive X-ray) measurement of the powder. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
