LiZn铁氧体的制备和吸波性能研究

Preparation and Microwave Absorption Properties of LiZn Ferrite

用溶胶-凝胶法制备了Li0.35Zn0.3Fe2.35O4粉体,采用HP8722ES矢量网络分析仪测量了样品在2～18GHz频率范围的复介电常数εr(εr=ε′-jε″)和复磁导率μr(μr=μ′-jμ″).采用传输线理论公式,对材料的吸波性能进行了模拟.结果表明,随着匹配厚度d的增加,吸波性能增强.当d=4mm时,材料的吸波曲线出现双吸收峰;d=5mm时,材料的吸收峰值位于4.4GHz,反射率为-19.96dB,-10dB吸收带为2.8～9.0GHz,带宽为6.2GHz.吸波材料在低频区有良好的吸波性能.

Li0.35Zn0.3Fe2.35O4 ferrite powder was prepared by Sol-Gel method.The electromagnetic parameters εr（εr=ε′-j ε″） and μr（μr=μ′-j μ″） in 2-18GHz band of the products were tested by HP 8722ES vector network analyzer.Microwave absorbing capability is simulated on the basis of transmission line theory.The result shows that the reflection loss decreases with the increase of thickness（d）.When the thickness is 4mm,the absorption curve shows two absorption peaks.When the thickness is 5mm,the absorption peak is located at 4.4GHz,the reflection loss is-19.96dB,and the absorption band of less than-10dB is from 2.8GHz to 9.0GHz with the bandwidth of 6.2GHz.Microwave absorbing capability is good in low frequency range.