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Estimation of the nucleation rate by differential scanning calorimetryA realistic computer model is presented for calculating the time-dependent volume fraction transformed during the devitrification of glasses, assuming the classical theory of nucleation and continuous growth. Time- and cluster-dependent nucleation rates are calculated by modeling directly the evolving cluster distribution. Statistical overlap in the volume fraction transformed is taken into account using the standard Johnson-Mehl-Avrami formalism. Devitrification behavior under isothermal and nonisothermal conditions is described. The model is used to demonstrate that the recent suggestion by Ray and Day (1990) that nonisothermal DSC studies can be used to determine the temperature for the peak nucleation rate, is qualitatively correct for lithium disilicate, the glass investigated.
Document ID
19920072788
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Kelton, Kenneth F.
(Washington University Saint Louis, MO, United States)
Date Acquired
August 15, 2013
Publication Date
September 1, 1992
Publication Information
Publication: American Ceramic Society, Journal
Volume: 75
Issue: 9 Se
ISSN: 0002-7820
Subject Category
Nonmetallic Materials
Accession Number
92A55412
Funding Number(s)
CONTRACT_GRANT: NAG8-873
Distribution Limits
Public
Copyright
Other

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