Primary crystals in ZrTiCuNiBe bulk glasses

ZrTiCuNiBe glasses can be prepared in massive form by quenching of the liquid melt with a cooling rate of about 10ks-1. During cooling down of the melt a small fraction of primary crystals in the glassy matrix is difficult to avoid. Morphology microstructure and chemical composition of these primary crystals have been investigated by optical microscopy, transmission electron microscopy (TEM) and TEM-EDX. Two types of crystal morphology were observed, dendritic and prismatic. TEM-EDX analysis (which cannot detect Be) indicate that these two types of crystals have similar composition. TEM diffraction of the prismatic crystals revealed an ordered orthorhombic structure with lattice parameters of a = 0.37 nm, b = 0.66 nm, c = 0.63 nm. The true composition of the prismatic crystals and the matrix was determined by FIM/AP-analysis. This analysis revealed a composition of the prismatic crystals according to ZrBe2 with small additions of Ti, Cu and Ni.