There exist three standard phenomenological models (normal growth,screw dislocation growth and 2-D nucleated gowth) that have been employed for the description of interface crystal growth processes in inorganic glasses.it was believed that one could decide which of these growth models was operative in a given system by inspectionof a plot of the reduced growth rate,U_R,as a function of undercooling.#DELTA#T.However,we have discovered that discerning the mechaism entails a more complex analysis,for which one has to compare the magnitudes of experiemntal and calculated growth rates as well as assess the physical parameters that ente rinto the theories.Furthermore,we have observed that growth mechanisms can change (perhaps several times) as the degree of undercooling of the melt is increased.We illustrate these points by means of analysing,and in some cases reanalysing,crystal growth data obtained for several different inorganic glasses.Since we limit our attention to interface controlled processes,only pseudo one component glasses where thermal dissipation effects are neglibible are considered.
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