Preparation and microwave absorbing properties of nano-rod barium ferrite

The nano-rod of barium ferrite was made of iron nitrate and barium nitrate as raw materials by combustion method of sol-gel and self-propagation. The composition, morphology and magnetic properties of barium ferrite nano-rod were characterized by X-ray diffraction analysis, transmission electron microscopy and vibrating sample magnetometer. The cement-based composite absorption materials of doping barium ferrite nano-rod was prepared, and its microwave absorbing properties were measured by reflection method. The results indicate that the average particle size and length of barium ferrite nano-rod are 40-60 nm and 100 nm respectively, the saturation magnetization and coercivity are 49.87 A·m²/kg and 63.1 A/m. When the contents of barium ferrite nano-rod in cement reaches 1.83% (by mass) and thickness of specimen is 20 mm, the least reflectivity of cement-based composite is -16.78 dB and bandwidth for -10 dB reaches 6 GHz in 2-18 GHz frequency range.