标题：Microstructure and properties of BN/Si3N4 composites with addition of microwave synthesized Y2O3-MgO nanopowders
作者：Zhao, Yujun; Wang, Yueyue; Zhou, Haifeng; Guan, Xiaoli
作者机构：[Zhao, Yujun; Wang, Yueyue; Zhou, Haifeng; Guan, Xiaoli] Qilu Univ Technol, Shandong Acad Sci, Coll Mat Sci & Engn, Key Lab Proc & Testing Technol Gla 更多
通讯作者：Zhao, Yujun;Zhao, YJ
通讯作者地址：[Zhao, YJ]Qilu Univ Technol, Shandong Acad Sci, Dept Mat Sci & Engn, Key Lab Proc & Testing Technol Glass & Funct Cera, Jinan 250353, Shandong, People 更多
关键词：BN/Si3N4 composites; Nanopowders; Dielectric properties;; Wave-transparent mechanisms
摘要：Y2O3-MgO nanocomposite powder was synthesized by a microwave technique and doped into gas-pressure sintered BN/Si3N4 composites to acquire a highly wave-transparent material that could be utilized in spacecrafts. The XRD and SEM analyses indicated that the main phases were rod-like beta-Si3N4 particles and MgSiO3. In this case, a BN/Si3N4 ceramic with 8 wt% Y2O3-MgO nanopowder displayed a density of 2.5 g/cm(3). The permittivity and transmission efficiency were approximately 4.6% and 71.4%, respectively, at frequencies of 8.2-12.4 GHz, which achieved the best overall wave-transparent performance. The porosity of the material in combination with the inclusion of the boron nitride component creates a synergistic effect that appears to contribute to wave transparent efficiency.