| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide inexpensive ferrite magnet powder that has excellent magnet characteristics in a stoichiometric composition and even in a composition region which is slightly excessive in AO than the stoichiometric composition, and to provide a method of manufacturing the magnet powder and an inexpensive bonded magnet that is improved in characteristics by using the magnet powder. <P>SOLUTION: To ferrite magnet powder is composed of the single 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>] 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 5.7≤n≤6.0. In sintering of the magnet powder, the atmosphere is controlled to a reducing atmosphere so that the single phase of the magnetoplumbite type crystal structure expressed by the chemical formula may be produced. The bonded magnet is manufactured by using this magnetic powder. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
