Tailoring the Dielectric and Mechanical Properties of Si3N4 Ceramics |
Seung Jun Lee, Seok-Min Yong, Jin-Woo Park, Jaeho Choi, Seungsu Baek |
The 4th Research and Development Institute, Agency for Defense Development |
질화규소 세라믹의 유전 및 기계적 특성 제어에 관한 연구 |
이승준, 용석민, 박진우, 최재호, 백승수 |
국방과학연구소 제4기술연구본부 |
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Abstract |
The present study investigates the effect of PMMA and BN content on microstructure, mechanical and dielectric
properties of silicon nitride(Si3N4) ceramics in Y2O3-Al2O3 additive system. The total additive content was fixed at
8 wt.% and the amount of PMMA varies from 0 to 40 wt.% and BN varies from 0 to 36 wt.%, respectively. The
crystalline phases of the samples were determined by X-ray diffraction analysis. All the sintered sample shows
complete transformation of α to β-Si3N4 during the sintering process indicated that the phase transformation was
unaffected by the PMMA or BN content. However, the microstructure shows that the residual porosity increased
with increasing PMMA and BN content. In addition, the flexural strength and the dielectric constant decrease with
addition of PMMA and BN due to the residual porosity. This article provides empirical study of design parameters
for Si3N4-based radome materials. |
Key Words:
$Si_3N_4$, Radome, Dielectric Properties, Flexural Strength |
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