Abstract
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 ammo-nium 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(HFSSTM)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 absorp-tion 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°.
基金项目
国家自然科学基金(51971111)
Foundation of National Defense Science and Technology Key Laboratory(6142908-KQ111501114)
NETL
NSTL
维普
万方数据