镀Al空心玻璃微球FeCo合金/环氧树脂复合材料的吸波性能

利用磁控溅射法对空心玻璃微球表面镀Al。研究了由镀Al空心玻璃微球FeCo合金/环氧树脂制成的复合材料在2~18GHz频段范围内的电磁特性, 利用模型计算了所制备样品的微波反射率。结果表明, 在镀Al空心玻璃微球和FeCo合金粉末总体积分数一定的条件下, 随着镀Al空心玻璃微球与FeCo 合金体积比的增加, 复合材料介电常数实部ε′减小， 虚部ε″ 变化不明显; 磁导率的实部μ′ 和虚部μ″ 均减小； 反射率峰值向高频方向移动。 当 镀Al空心玻璃微球与FeCo合金体积比2∶1时, 涂层厚度为2mm, 吸收峰值达到-29.69dB, 其面密度仅为3.71kg/m2, 吸收率小于-10dB的带宽达到2.4GHz。由此可见, 通过改变镀Al空心玻璃微球与FeCo合金的体积比, 可以调节电磁参数, 提高材料的吸波性能。 

Microwave absorbing properties of Al-coated hollow glass microspheres-FeCo powders/epoxy resin composites

The magnetron sputtering was employed to sputter Al on the hollow glass microspheres. The electromagnetic characteristic of the composites consisting of Al-coated hollow glass microspheresFeCo powders was studied in the frequency range of 2~18GHz. The microwave absorbing property (R) of the composite was theoretically calculated. It has been found that the ε′,μ′and μ″  of the composites decreased with increasing the volume fraction of the Al-coated hollow glass microspheres, while ε″ has no significant change, when the overall volume fraction of Al-coated hollow glass microspheres and FeCo powders was fixed. The calculated peak value of R was moved to high frequency. The material with Al-coated hollow glass microspheres and FeCo powders volume ratio of 2∶1 and thickness of 2mm achieves the maximum absorbing value of -29.69dB, and the surface density is only 3.71kg/m2, and the bandwidth (with respect to -10dB absorption) is 2.4 GHz. Thus through changing the volume ratio of Al-coated hollow glass microspheres and FeCo powders, the electromagnetic parameter of the composite could be adjusted and the microwave absorbing property of the materials could be improved.