NiFe1 . 98Nd0 . 02O4-Fe 双层吸波涂层设计及制备

目的制备高性能NiFe1.98Nd0.02O4-Fe双层吸波涂层。方法采用溶胶凝胶自燃烧法制备钕掺杂NiFe1.98Nd0.02O4。借助X射线衍射仪、扫描电镜和矢量网络分析仪对NiFe1.98Nd0.02O4和羰基铁的结构、形貌、电磁参数进行测试分析。采用遗传算法对NiFe1.98Nd0.02O4-羰基铁双层涂层的厚度进行优化设计。结果以环氧树脂为基体,以羰基铁和NiFe1.98Nd0.02O4为吸波剂的双层吸波涂层具备较好的吸波性能,厚度约1 mm,反射率在9.25~11.35 GHz范围内均小于-10 dB。结论 NiFe1.98Nd0.02O4层和羰基铁层在吸波性能上有很好的互补性,理论优化结果和实验结果相同。

Design and Preparation of Double-layer Microwave Absorbers Based on Carbonyl Iron and NiFe1 . 98Nd0 . 02O4

Objective To prepare high-performance double-absorbing coating NiFe_{1 . 98}Nd_{0 . 02}O₄ -Fe. Methods Nd substituted nickel ferrites ( NiFe_{1 . 98}Nd_{0 . 02}O₄ ) were prepared using the sol-gel-autocombustion method. The microstructures, morphology and the electromagnetic properties of NiFe_{1 . 98}Nd_{0 . 02}O₄ and carbonyl iron were characterized with X-ray diffraction ( XRD) , scanning electron microscopy ( SEM) and a vector network analyzer. The thickness of double-layers microwave absorption coating was optimized by the genetic algorithm ( GA) . Results Using carbonyl iron and NiFe_{1 . 98}Nd_{0 . 02}O₄ as absorbents, double composite absorbing coating with thickness d = 1 mm was prepared. The results showed that the reflection loss of coating was less than-10 dB over the range from 9. 25 GHz to 11. 35 GHz. Conclusion The results of measurements showed that the microwave absorption property of NiFe_{1 . 98}Nd_{0 . 02}O₄ and carbonyl iron were complementary to each other. The calculated RL agreed closely with the experimental results in the whole measured frequency range.