importance for the understanding of the observed often-preferential surface devitrification of a variety of vitre-
ous materials. According to the mechanism discussed here, the basic parameter of the system considered that
determines the preference to surface crystallization is—in addition to the surface specific energies—the misfit
parameter
. The parameter is a measure of the relative change in the volume of the glass in crystallization. In agreement with experimental results, it is found that in heating processes of glasses, the preferential surface
crystallization has to occur for systems with large values of the misfit parameter
. Moreover, in comparison with planar interfaces, the inhibiting effect of elastic strains on crystallization is even more decreased for glass
powders and rough surface structures of the glass samples. In this way, powders of glass, edges, corners, etc.
on the glass surface may act as centers for crystallization catalysis.