Applied Microscopy

Korean Society of Microscopy (한국현미경학회)
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Microstructural Characterizations on $(Na_{1/2}Pr_{1/2})TiO_3$ Ceramics

$(Li_{1/2}Pr_{1/2})TiO_3$ 세라믹의 미세구조 평가

  • Lee, Hwack-Joo (New Materials Evaluation Center, Korea Research Institute of Standards and Science) ;
  • Ryu, Hyun (New Materials Evaluation Center, Korea Research Institute of Standards and Science) ;
  • Park, Hyun-Min (New Materials Evaluation Center, Korea Research Institute of Standards and Science) ;
  • Cho, Yang-Koo (New Materials Evaluation Center, Korea Research Institute of Standards and Science) ;
  • Nahm, Sahn (Division of Materials and Metallurgical Engineering, Korea University)
  • 이확주 (한국표준과학연구원 물질량 표준부) ;
  • 류현 (한국표준과학연구원 물질량 표준부) ;
  • 박현민 (한국표준과학연구원 물질량 표준부) ;
  • 조양구 (한국표준과학연구원 물질량 표준부) ;
  • 남산 (고려대학교 공과대학 재료공학부)
  • Published : 2002.09.01
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Abstract

Microstructural investigations of $(Li_{1/2}Pr_{1/2})TiO_3$ (LPT) complex perovskite compounds were carried out using X-ray diffractometry and transmission electron microscopy. LPT has not only the ordering of A-site cation deficiencies but also has the antiphase and inphase tilting of oxygen octahedron and the antiparallel shift of cations. Both the antiphase boundaries and the ferroelastic domains are present in the microstructure. Spinodal decomposition is found in the microstructure. The measured dielectric properties were ${\varepsilon}_r=84.6,\;Q\;{\Large f}_o=776\;GHz,\;{\tau}_{f}=-233.66ppm/^{\circ}C$.

복합 페로브스카이트$(Li_{1/2}Pr_{1/2})TiO_3$ (LPT)의 미세구조를 X-ray diffractometry와 투과전자현미경으로 관찰하였다. LPT는 A-site 양이온 결핍에 의한 vacancy ordering을 갖고 있으며 산소 팔면체의 antiphase tilting과 inphase tilting 그리고 A-site 양이온의 anti-parallel shift 가 관찰되었다. 스피노달 분해에 의한 상변태도 관찰되었다. 측정된 NPT 재료의 유전체 특성은 ${\varepsilon}_r=84.6,\;Q\;{\Large f}_o=776\;GHz,\;{\tau}_{f}=-233.66ppm/^{\circ}C$이었다.

Keywords

References

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