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New Method for Determining the Nucleation and Crystal‐Growth Rates in Glasses
Author(s) -
Ray Chandra S.,
Fang Xiangyu,
Day Delbert E.
Publication year - 2000
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.2000.tb01287.x
Subject(s) - nucleation , differential thermal analysis , crystal (programming language) , polishing , materials science , grinding , crystal growth , analytical chemistry (journal) , mineralogy , chemistry , crystallography , optics , metallurgy , chromatography , physics , organic chemistry , computer science , diffraction , programming language
The rates for nucleation ( I ) and crystal growth ( U ) for a lithium disilicate (Li 2 O·2SiO 2 , LS 2 ) glass were determined, as a function of temperature, using a new differential thermal analysis (DTA) technique. This technique requires in situ nucleation and crystal‐growth heat treatment of a small amount of powdered sample inside the DTA apparatus, which then are followed by a DTA scan at a constant heating rate. The I and U values that have been determined at selected temperatures for the LS 2 glass are in excellent agreement with those reported in the literature. The technique also has been used to determine the concentration of quenched‐in nuclei in LS 2 glasses prepared from melts that have been quenched at different rates, which are in reasonable agreement with those estimated from theoretical considerations. This new DTA technique is less tedious, requires a smaller amount of sample, and is at least 10 times faster than the conventional methods that have been used to measure I and U . Also, no special sample preparation, other than simply grinding and screening the glass to a particle size that is suitable for use, is required in this technique, whereas grinding, polishing, or etching is required in conventional methods. The excellent agreement in the I or U values that have been determined for the LS 2 glass via the present and conventional methods demonstrates the accuracy, validity, and usefulness of this DTA method for rapid determination of the nucleation and crystal‐growth rates in glasses.