▎ 摘　　要

NOVELTY - A high-temperature-resistant broadband wave-absorbing structure composite material is composed of a composite material medium layer and a periodic structure layer, which are compounded in order from outside to inside. The composite material medium layer is a fiber preform reinforced ceramic matrix composite material comprising a wave-transmitting layer and a loss layer, in order from outside to inside. The periodic structure layer is a metal composite material. USE - High-temperature-resistant composite material is used in selective absorption of electromagnetic waves of different frequencies. ADVANTAGE - The high-temperature-resistant broadband wave-absorbing structure composite material effectively realizes broadband absorption of electromagnetic waves. The structural strength and heat resistance of the composite material is significantly improved due to the obvious improvement of the integrity, and due to the material properties. Due to the high-impedance surface, the composite material can achieve selective absorption of electromagnetic waves of different frequencies through different periodic structures, and has excellent tuning ability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the high-temperature-resistant broadband wave-absorbing structure composite material, which involves (i) selecting different combinations of fiber layers to prepare fiber preforms, in which organization of each layer of the fabric is preferably plain weave or 2/2 twill, (ii) processing the fiber preform at 300-1000degrees Celsius under vacuum or inert atmosphere, (iii) preparing interfaces on the fiber preforms by chemical vapor deposition or dip-pyrolysis, (iv) preparing matrix of the fiber preform with the interface by immersion-pyrolysis which is performed using 0.1-20 %mass wave absorber to obtain composite material medium layer, (v) processing the surface of the composite material medium layer and selecting periodic structure type according to the requirements of wave absorbing performance, and (vi) etching surface of the selected periodic structure and electroplating.