Elastic stresses in surface crystallization of glasses: phase transformations at spike tips

Abstract

Elastic energy, evolving in the crystallization of the tip of a spike located at a planar interface of a solid, is determined by finite element method calculations. The energy per volume of the newly evolving phase depends significantly on the geometry of the spike. In agreement with expectations expressed earlier, it tends to zero for thin needles. The results give additional support to the theoretical concept that differences in the degree of evolution of elastic strains in crystallization in the bulk and near interfaces may be the origin for the preferential surface crystallization of solids in general, and glasses as a special case. In particular, the results explain why sharp corners, edges etc. on the surface of the glass may act as catalysts for crystallization.