Microstructure and properties of BN/Si3N4 composites with addition of microwave synthesized Y2O3-MgO nanopowders

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 β-Si3N4 particles...

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Bibliographic Details
Published inCeramics international Vol. 45; no. 1; pp. 299 - 303
Main Authors Zhao, Yujun, Wang, Yueyue, Zhou, Haifeng, Guan, Xiaoli
Format Journal Article
LanguageEnglish
Published Elsevier Ltd 01.01.2019
Subjects
BN/Si3N4 composites
Dielectric properties
Nanopowders
Wave-transparent mechanisms
BN/Si3N4 composites
Nanopowders
Wave-transparent mechanisms
Dielectric properties
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Summary: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 β-Si3N4 particles and MgSiO3. In this case, a BN/Si3N4 ceramic with 8 wt% Y2O3-MgO nanopowder displayed a density of 2.5 g/cm3. 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.
ISSN:0272-8842
1873-3956
DOI:10.1016/j.ceramint.2018.09.166