| 摘要 |
PURPOSE:To obtain powder of title fine particles having great value of magnetization, appropriate coercive force, and superior temp. stability by heating and calcining a coprecipitate generated from a ferrous salt, ferric salt, Ba salt, specified metal salt, and alkaline aq. soln. CONSTITUTION:A coprecipitate is generated from a mixture of a ferrous salt and ferric salt wherein a proportion of ferric salt to the total of the ferrous salt plus ferric salt is 5-100% expressed in terms of Fe<2+>/(Fe<2+>+Fe<2+>), a Ba salt, a metal M salt [M is at least one bivalent metal selected from Co, Ni, Zn, Mg and at least one tetravalent metal selected from Ti, Sn, Zr, and Ge], and an alkaline aq. soln. By heating and calcining the coprecipitate, plate-shaped fine particles of oxide contg. Ba and Fe as primary components and having a crystal structure wherein a proportion of a peak intensity for 2theta=43.4 deg. to a peak intensity at 2theta=45.2 deg. in an X-ray diffraction analysis when Fe is used as target, are obtd. |
