摘 要：采用 sol－gel 方法制备 M 型六角锶铁氧体。利用 X 光衍射、透射电子显微镜和 VSM 对纳米晶样品进行了研 究。当热处理温度小于800℃‚样品存在复相。在同样条件 下‚压成薄片的样品存在硬磁与软磁 SrFe₁₂O₁₉／γ-Fe₂O₃ 的 纳米复合相的磁性交换耦合作用。温度为800℃的薄片样 品‚比饱和磁化强度σS 为75．6emu／g‚内禀矫顽力 Hcj 为 6015Oe‚最大磁能积 （ BH）Max 为1．87MGOe‚而粉末样品相 应的分别为75．9emu／g‚6400 Oe 和1．52MGOe。当热处理 温度大于850℃时‚只有单一 M 相。 

关键词：六角锶铁氧体；纳米复合；交换耦合；磁性

Abstract：Strontium hexaferrite powders are prepared by the sol-gel method.The samples are analyzed by X ray diffraction (XRD) , transmission electron microscope (TEM) , and vibrating sample magnetometer (VSM) .When thermal treatment temperature is below 800℃, there are two phases of γ Fe ₂O ₃ and SrFe ₁₂ O ₁₉ .In the same conditions, the samples pressed into a flake exist exchange coupling interaction on the magnetic properties between the two nanostructured phases of γ Fe ₂O ₃ and SrFe ₁₂ O ₁₉ .At this situation the thermal treatment at 800℃ produces a nanocomposite with a intrinsic coercivity of 6015 Oe, a maximum magnetization at 18 kOe of 75.6 emu/g and a maximum energy product of 1.87 MGOe as compared with the powder sample of 6400 Oe, 75.9 emu/g and 1.52MGOe respectively.Only a compound SrFe ₁₂ O ₁₉ is detected over 850℃.

Keywords：strontium hexaferrite;nanocomposite;exchange coupling;magnetic properties