Preparation and Microwave Absorbing Properties of Multi-layered Radar(Microwave) Absorbing Materials Composites

Based on the electromagnetic wave propagation laws,a three-layered sheet radar(mi- crowave)absorbing system with the impedance-graded structure was designed.The surface layer, composed of TiO_2,easily,realizes matching to the free space and protection from destroying.The last layer,made up of magnetic micropowder(MMP)ballmilled from Fe,Co,etc,has significant absorbing effects.The medium layer,comprised of MMP and carbon fibers,forms the impedance- graded structure from the surface to the last layer.The results of experimental measurement show that reflectivity for the three-layer absorber is below-8dB in the frequency range of(8-18)GHz. Tensile strength is 10.8MPa,and peeling strength is 75.2N/cm,satisfying the use of engineering.