Surface Crystallization of Metal-Metalloid-Glasses

Abstract

AbstractPreferential crystal nucleation and growth may occur at surfaces because of a decrease in surface energy, a greater ease of diffusion and stress relaxation or a change in surface composition. Segregation as well as selective oxidation are assumed to possess the strongest influence on surface crystallization.Crystal nucleation and growth at both surfaces of melt-spun ribbons has been studied systematically in a number of Ni-B and Co-B glasses by means of quantitative light and electron microscopy. Crystal diameter distributions indicate a transient type heterogeneous nucleatior mode for surface crystallization. The results will be compared wi th crystallization in the bulk.