Study On The Electro-Magnetic Parameter And Mircowave Absorption Property Of Carbon Nanotuber Composties

The electromagnetic parameters and the electro-magnetic wave absorption property of carbon nano-tube (CNT) composites were studied in this paper by means of experiment and simulation. Main work includes the study on the electromagnetic parameters of multi-wall CNTs and simulation of microwave-absorbing property, electro-magnetic wave absorption properties of epoxy/CNTs composites within X and K. band, and electromagnetic parameters and electro-magnetic wave absorption properties of Epoxy/CNT composites in C1 band.The result shows the wax/CNT composites have a high permittivity in 2-18GHz. The maximum is 65.35 (at 2GHz) for CNTs with the diameter of 40-60nm out of all CNTs. However, the permeability of all CNT composites is very low. The results show that the epoxy/CNT coating has very good electro-magnetic wave absorption property in X and K band.The permittivity of the CNT composites with matrix of epoxy resin is higher than that of wax-matrix. The permeability of all composites was still the same. Simulation results show that it is hard to achieve an application level while only using CNTs alone as the absorber in the band of 3-6GHz. The experiment results show that the magnetic materials can improve the absorption property in the low frequency bands. When using 80% carbonyl iron powders and 5% CNTs as the absorber, the peak occurs at 3.26GHz with a height of -7.18dB., As using 80% carbonyl iron powders composite as the back layer and 5% CNT composites as the front layer the absorption property reaches -20.75dB.