Doctoral Dissertations

Abstract

"The transformation of a synthetic mica composition K₂Mg₅Si₈O₂₀F₄ from amorphous to crystalline structure was studied isothermally at selected temperatures from 560°C to 1150°C. thermal changes associated with the transformation were followed by differential thermal analysis techniques. Structural changes promoted by the isothermal treatments were observed by density measurements, Debye-Scherrer X-ray diffraction techniques, electron replication microscopy, and electron scanning microscopy. Isothermal treatment at 450°C for 9 hours produces structural ordering in quenched K₂Mg₅Si₈O₂₀F₄ glass. Fluorine exerts a significant influence on the transformation temperature; decreasing amounts of fluorine producing increasing transformation temperatures. The crystallizing phase rapidly attains a limiting particle size and morphology at temperatures in the 600°C region. Treatments of quenches K₂Mg₅Si₈O₂₀F₄ glass at 900°C and above promotes a change from spherulitic to blocky crystal habit, accompanied by a more complete development of mica structure during growth"--Abstract, page ii.

Advisor(s)

Moore, Robert E., 1930-2003

Committee Member(s)

Tappmeyer, Wilbur P.
Hill, Otto H.
Guyon, John C. 1931-
Day, D. E.

Department(s)

Materials Science and Engineering

Degree Name

Ph. D. in Ceramic Engineering

Sponsor(s)

National Science Foundation (U.S.)

Publisher

University of Missouri--Rolla

Publication Date

1969

Pagination

viii, 69 pages

Note about bibliography

Includes bibliographical references (pages 66-68).

Rights

© 1969 William H. Daniels, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Library of Congress Subject Headings

Glass-ceramics -- Analysis
Mica
Crystallization

Thesis Number

T 2256

Print OCLC #

6009332

Electronic OCLC #

832732270

Share

 
COinS