Effect of carbon nanotube content on the radar absorbing properties of carbon nanotube/resin composites

The radar wave absorbing properties of carbon nanotube based composites were investigated. Carbon nanotubes were added to epoxy resin with different weights and dispersed by sonication to prepare radar absorption composite materials (RAM). Then the composite paste was put into an aluminium pan to form the test sample. Carbon nanotubes were characterized by TEM and radar absorbing properties were obtained by the arc reflectivity method. Results indicate that carbon nanotubes have excellent radar absorbing properties in the waveband of 2-18 GHz. The best parameters are obtained using mass fraction carbon nanotube additions of 8% and 10%. The highest absorbing peak of -22.55 dB at 12.32 GHz is obtained for the composite with an addition of 8% carbon nanotubes and the composite has a bandwidth of 2.56 GHz at R-8 dB and 4.00 GHz at R-5 dB. With an addition of 10%, the absorbing peak of -14.59 dB is located at 13.67 GHz with the largest bandwidths of 2.80 GHz at R-8 dB and 7.00 GHz at R-5 dB.