| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide inexpensive ferrite magnet powder that has excellent magnet characteristics even in a composition region which is excessive in Fe<SB>2</SB>O<SB>3</SB>than the stoichiometric composition. <P>SOLUTION: The ferrite magnet powder contains the phase of the magnetoplumbite type crystal structure expressed by the chemical formula of (A<SB>1-x</SB>R<SB>x</SB>)O-n[(Fe<SP>3+</SP><SB>1-y</SB>Fe<SP>2+</SP><SB>y</SB>)<SB>2</SB>O<SB>3</SB>] by ≥80% in mole ratio and has a mean particle diameter of 0.5-3.0 μm. In the chemical formula, the reference symbol A denotes at least one kind of element selected out of Ba and Sr, and the reference symbol R denotes at least one kind of element selected from among rare-earth elements. In addition, x, y, and n denote mole ratios and are respectively adjusted to meet 0<x≤0.6, 0<y≤0.05, and 6.0<n≤6.6. In sintering of the magnet powder, the atmosphere is controlled to a reducing atmosphere so that the phase of the magnetoplumbite type crystal structure expressed by the chemical formula may be produced by ≥80% in mole ratio. The bonded magnet is manufactured by using this magnetic powder. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
