소결시간에 따른 적층형 Mg0.93Ca0.07TiO3-(Ca0.3Li0.14Sm0.42)TiO3 세라믹스의 마이크로파 유전특성 |
조준엽, 윤기현, 김응수1, 김태홍2 |
연세대학교 세라믹공학과 1경기대학교 재료공학과 2한국전자통신연구원 정보화기술연구소 |
Effect of Sintering Time on Microwave Dielectric Properties of Layered Mg0.93Ca0.07TiO3-(Ca0.3Li0.14Sm0.42)TiO3 Ceramics |
Joon-Yeob Cho, Ki-Hyun Yoon, Eung Soo Kim1, Tae-Hong Kim2 |
Department of Ceramic Engineering, Yonsei University 1Department of Materials Engineering, Kyonggi University 2Information Technology Research Group, Electronics and Telecommunications Research Institute |
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ABSTRACT |
Effect of the sintering time on the microwave dielectric properties of the layered Functionally Graded Materials(FGMs) of the Mg0.93Ca0.07TiO3(MCT) with (Ca0.3Li0.14Sm0.42)TiO3(CLST) ceramics was investigated. The dielectric constant of layered FGMs specimens showed a nearly constant value and did not change significantly with sintering time. The quality factor, however, was affected by the relative density and thermal stress developed in each dielectric layer. With an increase of the relative density and the decrease of the induced thermal stresses, quality factor of the layered FGMs specimens increased and the quality factor was incluenced sensitively by the change of compressive stress developed in MCT layers which had a lower thermal expansion coefficient than that of CLST. For the layered FGMs specimen sintered at 1300$^{circ}C$ for 9h, the compressive stress developed in MCT layer showed the maximum value, which, in turn, the quality factor of the specimen was the minimum value. |
Key words:
Layered FGMs, $Mg_{0.93}Ca_{0.07}TiO_3$, $(Ca_{0.3}Li_{0.14}Sm_{0.42})TiO_3$, Quality factor, Thermal stress |
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