Spinodal decomposition of Ni–Nb–Y metallic glasses

✍ Scribed by N. Mattern; G. Goerigk; U. Vainio; M.K. Miller; T. Gemming; J. Eckert

• Book ID: 103998697
• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 607 KB
• Volume: 57
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/j.actamat.2008.10.028

✦ Synopsis

Phase-separated Ni-Nb-Y metallic glasses were prepared by rapid quenching from the melt. The early stages of decomposition were characterized in Ni-Nb-Y alloys with Ni contents of more than 60 at.%. Strongly correlated chemical fluctuations with a nanometer length scale were found to exist in the as-quenched state. The observed fluctuation lengths range from 5 to 12 nm, depending on the actual composition of the glass. The ''frozen-in" early stages of decomposition occur in the deeply undercooled melt due to the reduction in the critical temperature of liquid-liquid phase separation with Ni content. Annealing of the phase-separated Ni 70 Nb 15 Y 15 glass below the crystallization temperature leads to an increase in the amplitude of the fluctuations. However, the wavelength was unchanged, which provides evidence for the spinodal character of the decomposition.