Rate of Crystal Growth in Glass

Abstract

THE shape of the curve relating the rate of crystal growth to temperature of undercooling is familiar as a hump-backed curve. The shape of the low-temperature portion is usually ascribed to viscosity, and that at higher temperatures either to surface tension barriers hindering nucleus formation, or to a rather arbitrary undercooling factor based on the geometry of the phase diagram¹. The former is inadmissible where the growth of crystals already in existence is being considered, and the latter gives a very poor agreement with the experimental data, due, no doubt, to the arbitrary nature of the assumptions involved.