Mechanical reinforced lightweight multifunctional metastructure with ultrabroadband microwave absorption

It was difficult to solve the conflict of integrating the lightweight property, mechanical resistance, and broadband microwave absorption into one composite structure. Herein, the glass fiber (GF)/carbon fiber (CF) reinforced lightweight multifunctional metastructure with mechanical resistance and broadband microwave absorption was designed and optimized through the genetic algorithms and fabricated with the autoclave-vacuum bag technique. The proposed GF/CF reinforced metastructure (GF/CFRM) covered the -10 dB effective bandwidth in the full frequency band of 2-18 GHz with average reflectivity of -16.7 dB. The proposed electromagnetic theory was effective to predict the reflectivity of the metastructure. The GF/CFRM achieved the flexural strength of 42 MPa with the areal density and equivalent density of 8.26 kg/m2. The addition of the patterned resistive film introduced multiple absorption peaks in different frequency points. The integration of the lightweight property, load bearing, and broadband microwave absorption was realized.