Variation of Dielectric Constnat with Grain Size of Pyrochlore Phase in the PMN-Pyrochlore Diphasic Mixtrues

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J. Korean Ceram. Soc. > Volume 30(5); 1993 > Article

Journal of the Korean Ceramic Society 1993;30(5): 365.

Pyrochlore상의 입자크기에 따른 PMN-Pyrochlore 2상 혼합체의 유전율 변화

허강일, 김정주, 조상희

경북대학교 무기재료공학과

Variation of Dielectric Constnat with Grain Size of Pyrochlore Phase in the PMN-Pyrochlore Diphasic Mixtrues

ABSTRACT

Variation of dielectric constant in PMN-Pyrochlore diphasic mixtures were investigated with grain size of pyrochlore phase. Size of pyrochlore phase was controlled by the numbers of calcining and sedimentation method during powder processing. When grain size of pyrochlore phase is large in the sintered specimen, dielectric constant slowly decreased with increase of amount of pyrochlore phase. On the contary, grain size of pyrochlore phase is small, dielectric constant drastically decreased. It was thought that small sized pyrochlore grains more easily surrounded high dielectric phase (perovskite PMN) than large ones with addition of pyrochlore phase.