Morphology of surface crystallites on amorphous Fe87Zr7B5Cu1

Abstract

Surface crystallites a few tens of nanometres in breadth have been observed on the as-melt-spun surface of an alloy of compositionFe ₈₇ Zr ₇ B ₆ Cu ₁. These crystallites are preferentially oriented, and exhibit a (2 0 0) texture. Heat treatments at temperatures in the interval 623–773 °C caused the surface grains to coarsen and new, randomly oriented crystals to form. Compositional inhomogeneities were found to contribute to the formation of the surface crystallites. Results suggest that surface energy effects are more important during the nucleation of crystallites in the liquid than they are below the glass transition temperature.