• 제목/요약/키워드: $Pb(Mg_{1/2}Nb_{1/2})O_3$

검색결과 196건 처리시간 0.022초

Sol의 물리화학적 변수들이 $Pb(Mg, Zn)_{1/3}Nb_{2/3}O_3$ 박막의 우선 배향성에 미치는 효과 (Effects of Physico-chemical Factors of Sol on the Degree of Preferred Orientation in $Pb(Mg, Zn)_{1/3}Nb_{2/3}O_3$ Thin Films)

  • 조문규;장현명;김광수
    • 한국세라믹학회지
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    • 제32권3호
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    • pp.305-312
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    • 1995
  • Thin films of Pb(Mg, Zn)1/3Nb2/3O3 were fabricated by spin coating the Pb-Mg-Zn-Nb-O complex alkoxide sols on(111) Pt-coated MgO (100) planes. It was observed that the content of H2O and the rheological characteristics of sol greatly influenced the orientation of perovskite grains after thin-film formation. A strong preferential orientation of (100)-type planes of the perovskite grains was obtained for the sol aged for 15 days with the molar ratio of H2O to total metal alkoxides=2. As small angle X-ray scattering experiment in the Porod region was performed to correlate the observed preferential orientation with the network structure of precursors at various stage of aging. It was shown that the degree of branching of the Pb-Mg-Zn-Nb-O precursor chain had a direct effect on the preferred oreintation, and weakly branched precursor systems led to highly oriented grains after thin-film formation.

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$Pb(Mg_{1/3}Nb_{2/3})O_3$ 고용체의 규칙격자 구조에 있어서 장거리 규칙도의 의존성 (Dependency of Long-range Order Parameter on the Ordered Structure of $Pb(Mg_{1/3}Nb_{2/3})O_3$ Solid Solutions)

  • 박경순;김좌연;이재원;김광배
    • Applied Microscopy
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    • 제28권3호
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    • pp.415-424
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    • 1998
  • [ $Pb(Mg_{1/3}Nb_{2/3})O_3$ ] (PMN) 고용체의 고분해능 격자 이미지에 있어서 장거리 규칙도의 의존성을 컴퓨터 이미지 시뮬레이션을 이용하여 연구하였다. 컴퓨터 이미지 시뮬레이션은 multislice 방법으로 시편 두께, 초점 거리, 장거리 규칙도를 변화시켜 실시하였다. PMN에 있어서, 규칙격자 구조를 가지는 격자 이미지는 장거리 규칙도에 주로 의존하는 것을 발견하였다. 완전한 규칙격자 구조를 가지는 이미지는 유사 육방정 형태를 보였다 장거리 규칙도가 감소함에 따라, 유사 육방정 형태로부터 직사각형 형태로 변화되었고, 완전한 불규칙격자 구조를 가지는 이미지는 직사각형 형태를 보였다. 또한, 한 주어진 장거리 규칙도에서 시뮬레이션으로 얻은 이미지는 B-위치 양이온의 함량에 관계없이 거의 동일하였다.

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Nd, La, K, Na이 치환된 $Pb(Mg_{1/3}Nb_{2/3})O_3$ 세라믹의 구조 및 유전 성질에 관한 연구 (Structural and Dielectric Properties of $Pb(Mg_{1/3}Nb_{2/3})O_3$ Ceramics Substituted by Nd, La, K and Na)

  • 권숙화;박휴범;김정;홍영식;김시중
    • 한국세라믹학회지
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    • 제32권7호
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    • pp.839-845
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    • 1995
  • The structural and dielectric properties of Pb(Mg1/3Nb2/3)O3 ceramics substituted by Nd3+, La3+, K+ and Na+ were studied over 0~50 at.% substituent content. The 1 : 1 ordering behavior of Mg2+ and Nb5+ ions in the B site sublattice was observed in Nd3+-and La3+-modified compounds. The degree of ordering was increased with Nd3+, La3+ content in the compounds. But K+-or Na+-modified compounds did not exhibit the ordering behavior. This was explained by charge and size effect of A and B site cations and oxygen vacancies. As the mole fractions of substituent increased, the maximum values of dielectric constants were rapidly decreased and the phase transitions were broadened. Phase transition temperature was correlated with the covalency of A-O and B-O bonding.

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공진법 기반의 [011] 분극 Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 압전단결정 물성규명 (Characterization of [011] Poled Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 Single Crystals by Resonance Method)

  • 제엽;심민섭;조요한;이원옥;이상구;이정민;서희선
    • 한국전기전자재료학회논문지
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    • 제34권6호
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    • pp.466-474
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    • 2021
  • [011] poled ternary Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) single crystals have been investigated for active materials for acoustic transducers because of their high piezoelectric properties in both shear and transverse modes. In order to use [011] poled PIN-PMN-PT single crystals for acoustic transducers, the characterization of full-matrix material properties is required. In this study, full sets of compliance, dielectric, and piezoelectric constants of [011] poled rhombohedral PIN-PMN-PT were measured by a resonance method. Dimensions and geometries of 12 samples were proposed for measuring 17 independent material constants of [011] poled rhombohedral PIN-PMN-PT single crystals. Two sets of samples with different PT concentrations, 0.24PIN-0.49PMN-0.27PT and 0.24PIN-0.46PMN-0.30PT, were fabricated and their material properties were measured. Measured impedance spectra and simulated impedance spectra of the samples were compared to check the accuracy of the measurements.