Directional crystallization in the bismuth-strontium-calcium-copper-oxygen system: Effect of phase separation.

Persistent Link:
http://hdl.handle.net/10150/186040
Title:
Directional crystallization in the bismuth-strontium-calcium-copper-oxygen system: Effect of phase separation.
Author:
Kim, Seong-Jin.
Issue Date:
1992
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Novel unidirectional crystallization was tested in glasses of the Bi-Sr-Ca-Cu-O system to produce highly oriented microstructures. Some evidence of liquid-liquid phase separations on cooling melts of Bi₂Sr₂Ca₁Cu₂Oₓ and Pb₀ͺ₃₂Bi₁ͺ₆₈Sr₁ͺ₇₅Ca₂Cu₃Oₓ is found for the first time from Differential Thermal Analysis (DTA), X-ray Diffraction (XRD), and Transmission Electron Microscope (TEM). This made it difficult to produce highly oriented microstructures through the present route because one of the phases in the phase separated structure is likely close to "R"-phase composition and lead to copious nucleation of "R"-phase on heating. This also resulted in sequential crystallization of the current liquids, first to "R"-phase and then to the Bi₂Sr₂Ca₁Cu₂Oₓ phase. Theoretical modelling was performed to understand general questions in the present route. The model suggests that a liquid with high interfacial energy is a good candidate for the present route to produce highly oriented microstructures. The model was tested in lithium diborate glass and showed a highly oriented microstructure. Thus, unidirectional crystallization is generally an attractive processing option for a liquid free of phase separation.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Dissertations, Academic.; Materials science.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Materials Science and Engineering; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Uhlmann, D. R.; Birnie, D. P., III

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleDirectional crystallization in the bismuth-strontium-calcium-copper-oxygen system: Effect of phase separation.en_US
dc.creatorKim, Seong-Jin.en_US
dc.contributor.authorKim, Seong-Jin.en_US
dc.date.issued1992en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractNovel unidirectional crystallization was tested in glasses of the Bi-Sr-Ca-Cu-O system to produce highly oriented microstructures. Some evidence of liquid-liquid phase separations on cooling melts of Bi₂Sr₂Ca₁Cu₂Oₓ and Pb₀ͺ₃₂Bi₁ͺ₆₈Sr₁ͺ₇₅Ca₂Cu₃Oₓ is found for the first time from Differential Thermal Analysis (DTA), X-ray Diffraction (XRD), and Transmission Electron Microscope (TEM). This made it difficult to produce highly oriented microstructures through the present route because one of the phases in the phase separated structure is likely close to "R"-phase composition and lead to copious nucleation of "R"-phase on heating. This also resulted in sequential crystallization of the current liquids, first to "R"-phase and then to the Bi₂Sr₂Ca₁Cu₂Oₓ phase. Theoretical modelling was performed to understand general questions in the present route. The model suggests that a liquid with high interfacial energy is a good candidate for the present route to produce highly oriented microstructures. The model was tested in lithium diborate glass and showed a highly oriented microstructure. Thus, unidirectional crystallization is generally an attractive processing option for a liquid free of phase separation.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectDissertations, Academic.en_US
dc.subjectMaterials science.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineMaterials Science and Engineeringen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairUhlmann, D. R.en_US
dc.contributor.chairBirnie, D. P., IIIen_US
dc.contributor.committeememberSchrimpf, R. D.en_US
dc.contributor.committeememberO'Hanlon, J. F.en_US
dc.contributor.committeememberZelinski, B. J. J.en_US
dc.identifier.proquest9307699en_US
dc.identifier.oclc714123389en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.