Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.advisor | 김희택 | - |
dc.contributor.author | 최대우 | - |
dc.date.accessioned | 2020-04-07T16:58:59Z | - |
dc.date.available | 2020-04-07T16:58:59Z | - |
dc.date.issued | 2008-02 | - |
dc.identifier.uri | https://repository.hanyang.ac.kr/handle/20.500.11754/147386 | - |
dc.identifier.uri | http://hanyang.dcollection.net/common/orgView/200000408340 | en_US |
dc.description.abstract | Perovskite 구조를 갖는 PbTiO3는 작은 유전율, 높은 상전이온도 그리고 전기기계결함 계수의 이방성, 자발분극 및 초전계수가 큰 것등의 특징이 있지만 소결이 어렵다는 점과 고온에서 분극처리를 행하지 않으면 충분한 결합계수가 얻어지지 않는 결점을 가지고 있다. 따라서 이러한 결점을 개선하기 위한 방법으로써 PbTiO3에 대한 첨가물의 효과가 고상반응법에 의해 연구 되었으며 그 결과 Pb의 일부를 희토류나 알카리류의 원소로 치환할 경우 소결 및 분극 처리가 용이하게 되었다는 연구가 보고되었다. 특히 Pb1-xLaxTiO3(PLT)의 조성이 우수한 것으로 알려져 있다. 본 연구에서는 기존의 습식 밀링공정 뒤 건조된 파우더를 하소 과정 가운데 합성되는 고상반응과는 달리 높은 기계적 에너지가 화학에너지로 변화되는 SPEX Milling장비를 이용하여 기계화학적 합성으로 중간 하소 공정이 없는 Perovskite구조의 PLT를 제조해 보았다. 본 실험에서는 SPEX Milling시간에 의한 상변화 및 입자 사이즈 변화, 밀도를 살펴보았고 소결 온도에 따른 상변화, 밀도와 표면과 단면의 소결상태와 grain 크기와 유전율과 품질계수를 X선 회절과 전자현미경, 아르키메데스, 고성능 LCR meter를 이용하여 분석해보았다.; Lead titanate(PT) ceramics modified by rare earth elements and alkaline earth elements have emerged as highly promising materials for several piezo-electric applications due to existensce of large electro-mechanical anisotropy in the coupling factors along and transverse direction of polarization. These modified materials are extremely good for high frequency applications. Pyroelectric PT ceramics have been found useful for use in theraml imaging and human detection. Lanthanum doped lead titanate(PLT) ceramics display excellent electro-optic and photostriction properties. The PLT ceramics have been widely studied for applications in dynamic random access memories(DRAM), uncooled infrared detectors and electro-optic devices, due to their large electro-mechanical anisotopy in the coupling factors along and perpendicular to the directon of polarization and large pyroelectric coefficient along the polarization axis. In general, these properties of lanthanum doped lead titanate materials mostly depended on the lanthanum concentration and one of the characteristics can be optimized by adjusting the molar ratio of Pb/La. The PLT ceramic powder are conventionally prepared by solid-state recation, sol-gel process, chemical precipitation, metallo-oranic decomposition(MOD) process, or hydrothermal treatment. In all these methods, calcinations at more of less high temperature are needed to get pure crtstaalized perovskite Pb1-xLaxTiO3. however, the homogeneity, morphology and size of the particle, which greatly affect the sinterability and the property of the ceramics, are difficult to control due to the high temperature treatment during the preparation. The mecahnochemical Process is superior to both the conventional solid-state reaction and the wet-chemistry-baseed processing routes for the ceramic powder preparation for several reasons. It uses low-cost and widely available oxides as starting materials and skips the calcination step at an intermediate temperature, leading to simplified process. The influence of milling Time and Sintering Temperature on the phase formation, crystal structure, density and powder morphology was observed. | - |
dc.publisher | 한양대학교 | - |
dc.title | 기계화학공정을 이용한 perovskite 구조의 Lead Lanthanum Titanium oxdie의 제조 및 평가 | - |
dc.title.alternative | Preparation and characteristic Perovskite structure Lead Lanthanum Titanium Oxide by Mechano Chemical Process | - |
dc.type | Theses | - |
dc.contributor.googleauthor | 최대우 | - |
dc.contributor.alternativeauthor | Choi, Dae-Woo | - |
dc.sector.campus | S | - |
dc.sector.daehak | 대학원 | - |
dc.sector.department | 정밀화학공학과 | - |
dc.description.degree | Master | - |
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