Preparation and phase analysis of YNi2B2C

Abstract The recently discovered superconducting compound YNi 2 B 2 C has been investigated regarding formation and phase composition for different starting stoichiometries. The arc-melted and annealed samples were examined by X-ray diffraction, scanning electron microscopy with EDX/WDX for local compositional analysis, and differential thermal analysis. As-melted samples contain secondary phases which are reduced under appropriate annealing conditions. For a carbon-rich starting stoichiometry, phase pure bulk YNi 2 B 2 C can be produced. In addition, the melting temperature of YNi 2 B 2 C has been determined by a pyrometric measurement. Since the first single crystals have been successfully grown with the aid of a Ni-rich flux, Ni-rich starting stoichiometries were more closely investigated for their phase composition.