Modification of NiCo/NiFe-coated carbon fibers to attenuate centimeterwave

The modification of NiCo/NiFe-coated carbon fibers is studied to improve the attenuation properties in centimeter wave band. The oxidation modification has been adopted after carbon fibers(CF) is coated with Ni-Fe or Ni-Co by electroless plating, and the prepared products are characterized by scanning electron microscope (SEM), thermogravimetric analyzer(TG), X-ray powder diffraction(XRD) and vector network analyzer. The results showed that metal nickel is still exist in Ni-Fe-CFs after annealing in air at 500 °C for 1 h, and the antioxidative properties of Ni-Fe coating are better. The attenuation properties of Ni-Fe-CFs are slightly better compared to the original material from 3.92 GHz to 14.8 GHz. However the coated Ni-Co alloys are transformed entirely into oxides and phosphides under the same conditions. The attenuation of Ni-Co-CFs is obviously higher than the original material from 4.32 GHz to 16.24 GHz, and the strongest attenuation is 6.44 dB at 16 GHz.