碳纤维/铁硅铝复合材料的低频吸波性能

为获得吸波性能良好的吸波材料,将电阻型吸波剂碳纤维和磁损耗型吸波剂FeSiAl片状磁粉复合,以石蜡为基体,利用模压法制备出复合材料。采用激光粒度分析仪、扫描电子显微镜(SEM)、X射线衍射仪(XRD)对单一吸波剂进行了测试分析。结果发现,片状FeSiAl磁粉的粒度在数十到几百微米之间;碳纤维表面留有活性物质,截面处能看到皮芯结构;XRD衍射图谱中,FeSiAl呈现出bcc结构。对复合吸波材料的电磁参数进行测量对比,结果表明,FeSiAl片状磁粉在1~3GHz内的最佳反射率达到-40.7dB,有效吸收频带宽度约为0.5GHz;当加入长度等于4mm,含量为0.4%(质量分数)的碳纤维时,碳纤维/铁硅铝复合材料吸波性能最佳,其反射率为-49.6dB,有效吸收频带宽度为1.0GHz;FeSiAl片状磁粉平行于吸波片表面排列时,材料的反射率减小,吸波性能增强。

Absorbing Properties of Carbon Fiber/FeSiAl Composite in Low Frequency Band

In order to obtain better absorbing performance of absorbing material,using carbon fiber as the re-sistor type absorbent and FeSiAl magnetic flake as the magnetic loss type absorbent,with paraffin as the matrix,the composite material was prepared by molding method.Single absorbing agent was tested by using laser particle size analyzer,scanning electron microscope (SEM),X-ray diffraction (XRD)analysis.The results showed that the parti-cle size of FeSiAl magnetic flake is between tens to hundreds of microns.Active substances existed on the surface of carbon fiber,skin-core structure can be seen from the cross-section.XRD diffraction pattern proved that FeSiAl ap-peared bcc structure.For the measurement comparison of electromagnetic parameters of composite absorbing material, the results showed that the best reflectivity of FeSiAl magnetic flake reached -40.7 dB within 1-3 GHz,effective absorption band width was about 0.5 GHz.Absorbing performance of carbon fiber/FeSiAl composite was strongest when the length and content of carbon fiber were about 4 mm,and 0.4 wt%,respectively,accompanied by a reflecti-vity value of -49.6 dB,an effective absorption band width of 1.0 GHz.While sample surface was parallel to the ar-rangement direction of FeSiAl magnetic flake,the reflectivity of material decreased,which illustrates a strengthened wave absorption performance.