Preparation of cobalt-containing, acicular, magnetic iron oxides
    7.
    发明授权
    Preparation of cobalt-containing, acicular, magnetic iron oxides 失效
    含钴,针状,磁性氧化铁的制备

    公开(公告)号:US4770903A

    公开(公告)日:1988-09-13

    申请号:US45552

    申请日:1987-05-04

    CPC分类号: G11B5/712 G11B5/70657

    摘要: Acicular, magnetic iron oxide consisting of a core of gamma-iron(III) oxide and a ferrite shell containing a total of from 0.4 to 12% by weight of cobalt(II) ions and from 0.1 to 15% by weight of iron(II) ions, the percentages being based on the total amount of magnetic material, is prepared by a process in which an iron(II) hydroxide precipitate is applied to the gamma-iron(III) oxide core in a first stage and an iron-(II)/cobalt hydroxide precipitate is applied to the said core in a second stage, and the core is then converted to the ferrite shell by oxidation.

    摘要翻译: 针状磁性氧化铁由氧化铁(III)的核心和总共含有0.4〜12重量%的钴(II)离子和0.1〜15重量%的铁(II)的铁氧体壳组成 )离子,其百分比基于磁性材料的总量,通过其中将氢氧化铁(II)沉淀物施加到第一阶段中的γ-铁(III)氧化物核和铁 - ( II)/氢氧化钴沉淀物在第二阶段施加到所述芯上,然后通过氧化将芯转变成铁氧体壳。