Manufacture of acicular ferromagnetic iron particles
    2.
    发明授权
    Manufacture of acicular ferromagnetic iron particles 失效
    针状铁磁铁颗粒的制造

    公开(公告)号:US4178171A

    公开(公告)日:1979-12-11

    申请号:US888508

    申请日:1978-03-20

    摘要: A process for the manufacture of acicular ferromagnetic iron particles by reducing acicular iron(III) oxide hydroxides which consist of pure synthetic lepidocrocite or a mixture of synthetic goethite and at least 70% by weight of synthetic lepidocrocite.The iron(III) oxide hydroxides used carry, on their surface, an alkaline earth metal cation and an anion of a monobasic, dibasic or tribasic aliphatic carboxylic acid of up to 6 carbon atoms or an organic compound containing at least two groups capable of chelating the alkaline earth metal cation, and are produced in such a way that they consist of at least 70 percent by weight of lepidocrocite and have a length-to-width ratio of not less than 15:1.Reduction of such iron(III) oxide hydroxides gives iron particles with pronounced shape anisotropy, which exhibit both good magnetic properties and a narrow field strength distribution.

    摘要翻译: 通过还原针状铁(III)氢氧化物来制造针状铁磁性铁粒子的方法,该针状铁氧化物由纯合成锂铁矿石或合成针铁矿和至少70%重量的合成锂铁矿石混合物组成。 所用的氧化铁(III)氢氧化物在其表面上带有至多6个碳原子的一元,二元或三元脂肪族羧酸的碱土金属阳离子和阴离子,或含至少两个能够螯合的基团的有机化合物 碱土金属阳离子,并且以这样的方式制备,使得它们由至少70重量%的氯铁矿石组成,并且具有不小于15:1的长宽比。 这种氧化还原铁(III)氢氧化物的还原产生具有显着形状各向异性的铁颗粒,其具有良好的磁性能和窄的场强分布。