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Grain growth kinetics in liquid-phase-sintered zinc oxide-barium oxide ceramicsGrain growth of ZnO in the presence of a liquid phase of the ZnO-BaO system has been studied for temperatures from 1300 to 1400 C. The specimens were treated in boiling water and the grains were separated by dissolving the matrix phase in an ultrasonic bath. As a consequence 3D grain size measurements were possible. Microstructural examination shows some grain coalescence with a wide range of neck size ratios and corresponding dihedral angles, however, most grains are isolated. Lognormal grain size distributions show similar shapes, indicating that the growth mechanism is invariant over this time and temperature. All regressions between G exp n and time for n = 2 and 3 proved statistically significant. The rate constants calculated with the growth exponent set to n = 3 are on the same order of magnitude as in metallic systems. The apparent activation energy for growth is estimated between 355 and 458 kJ/mol.
Document ID
19920036194
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Yang, Sung-Chul
(Rensselaer Polytechnic Institute, Troy, NY, United States)
German, Randall M.
(Pennsylvania State University University Park, United States)
Date Acquired
August 15, 2013
Publication Date
December 1, 1991
Publication Information
Publication: American Ceramic Society, Journal
Volume: 74
ISSN: 0002-7820
Subject Category
Nonmetallic Materials
Accession Number
92A18818
Funding Number(s)
CONTRACT_GRANT: NAG3-1095
Distribution Limits
Public
Copyright
Other

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