中文摘要：

采用高分子凝胶法制备了纳米镍铁氧体，然后用热压法制备了镍铁氧体／聚苯乙烯复合材料。镍铁氧体的结构、形貌和复合材料的电磁性能分别采用X射线衍射仪（XRD）、透射电镜（TEM）和HP8510网络分析仪进行了研究。结果表明，当煅烧温度为600℃时，镍铁氧体晶相生成。随着煅烧温度的升高，镍铁氧体晶体晶型趋向完整。在X波段，复合材料的复介电常数和复磁导率值随着镍铁氧体煅烧温度的升高而增大。1000℃煅烧的镍铁氧体所制备的镍铁氧体／苯乙烯复合材料在11．47GHz处的最小反射率为-12．67dB。

英文摘要：

NiFe2O4 nanoparticles were synthesized by the polyacrylamide gel method. The nickel ferrite/polystyrene composites were prepared by the hot pressing method. The structural characteristics, morphology of NiFe204 and electromagnetic properties of the composites were analyzed by X-ray diffraction （XRD）, transmission electron microscope （TEM） and HP8510 network analyzer. The results indicated that a pure spinel structure of NiFe2O4 formed at 600℃. The NiFe204 was better crystallized with the increase of calcining temperature. The complex permeability and complex permittivity of the composites in X-band （8.2-12.4GHz） frequency range increased with the increase calcining temperature of NiFe204. The composite with ferrite calcined at 1000℃ showed a minimum reflection loss of -12.67dB at 11.47GHz.