Enhanced microwave absorption properties of nickel-coated carbon fiber/glass fiber hybrid epoxy composites-towards an industrial reality

Abstract

The Nickel-coated carbon fibers (NiCFs)/glass fibers (GFs) hybrid epoxy composites were manufactured by employing papermaking technology to produce NiCFs/GFs paper followed by composites liquid molding. The microwave absorbing properties of single-layered and double-layered NiCFs/GFs hybrid epoxy composites were evaluated. The reflection loss (RL) were calculated by the measured complex permittivity and permeability using waveguide method by vector network analyzer in the X-band (8.2-12.4 GHz) range. The double-layered composites were fabricated by using matching layer and absorbing layer to enhance the microwave absorption performance. The enhanced microwave absorbing properties of double-layered composites with minimum RL of -48.1 dB and effective absorption bandwidth of 3.2 GHz in the X band can be achieved when the total thickness of the matching layer and absorbing layer is 2.5 mm, which is attributed to synergistic effect of improved impedance matching characteristic and superior microwave attenuation capability of the absorbing layer, demonstrating that the NiCFs/GFs hybrid epoxy composites can be a promising candidate of high performance microwave absorbing materials for realizing industrialization.