Broadband absorption of macro pyramid structure based flame retardant absorbers  

作　　者：Hengda Sun Ying Zhang Yue Wu Yue Zhao Ming Zhou Lie Liu Shaolong Tang Guangbin Ji 

机构地区：[1]College of Materials Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China [2]General Test Systems Inc.,Shenzhen 518102,China [3]National Laboratory of Solid State Microstructures,Nanjing University,Nanjing 210093,China

出　　处：《Journal of Materials Science & Technology》2022年第33期228-238,共11页材料科学技术（英文版）

基　　金：financially supported by the National Nature Science Foundation of China(No.51971111);the Foundation of National Defense Science and Technology Key Laboratory(No.6142908-KQ111501114)。

摘　　要：Flame-retardant materials with good electromagnetic wave absorption play an increasingly important role in Over-the-Air(OTA)tests in microwave anechoic chambers.In this work,carbon nanotubes and ammonium polyphosphate(CNTs@APP)composite were prepared by crosslinking with the silane coupling agent(KH550).The flame retardancy is improved with the increase of APP.However,the microwave absorption performance(MAP)and processing difficulty changed greatly as well.Therefore,magnesium aluminum double-layer metal hydroxide(LDH)was obtained by coprecipitation method and processing into the coating,so as to realize flame retardancy which reaches the limiting oxygen index(LOI)of 24.8%and good MAP at the same time.Then,a high-frequency structure simulator(HFSS^(TM))was used to simulate the pyramid model to realize the broadband absorption,and the optimal parameter range was obtained,that is,when the total height of the material is 40 mm,the height of the base accounts for 1/5-1/3,and the tangent of the half top angle is near 1/5,which result in the best MAP.Finally,the broadband absorption of 14.36 GHz(3.64-18 GHz)was realized when the base height is 1/3,and the broadband absorption of 14 GHz(4-18 GHz)can be realized under the condition of large-angle oblique incidence of 0°-60°.

关 键 词：Electromagnetic wave absorption Broad bandwidth Pyramid structure Flame retardant HFSS^(TM) 

分 类 号：TB332[一般工业技术—材料科学与工程]