中文摘要：

采用溶胶-凝胶与自蔓延燃烧相结合的方法制备出碳．纳米铁氧体复合材料，应用X射线衍射仪、扫描电镜分别对产物的晶体结构和微观形貌进行了表征分析，着重对比研究了超细碳材料加入前后的变化。利用小型烟箱试验测出产物在军用红外波段质量消光系数大于1．1m^2／g；利用矢量网络分析仪测试其在2～18GHz的电磁参数，并得到损耗角正切值随频率变化的曲线。结果表明：在纳米铁氧体中添加超细碳材料，铁氧体原有的磁损耗不变，介电损耗值有了显著提高，从而增加了电磁波的总损耗。由此证实超细碳-纳米铁氧体复合材料具有宽频吸波特性。

英文摘要：

Nano-ferrite composites were synthesized by sol-gel method and SHS. Crystal structure and surface appearance of products were investigated by XRD and SEM. Mass extinction coefficients of composites were more than 1.1m^2/g in the IR range by smoke box. Electromagnetic parameters were measured by vector network analysis from 2 GHz- 18GHz. The curve that tangent of loss angle change with frequency was drawn. The results showed that when super-fine carbon material was added into nano-ferrite, the dielectric loss was enhanced, and so electromagnetic loss was increased. It was proved that nano-ferrite composite should be acted as broad-band microwave absorbers. An approach was offered to broaden frequencies of stealth materials.