Structural features of the extraordinary low glass transition temperature for Au65Cu18Si17 bulk metallic glass

Makoto Matsuura, Wei Zhang, Shinichi Yamaura, Takashi Fujita, Koji Ohara, Shinji Kohara, Jun Mizuno

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Au65Cu18Si17 bulk metallic glass (BMG) exhibits an extraordinary low glass transition temperature (<100°C) and a wide supercooled liquid region. In order to elucidate the structural features of the extraordinary low glass transition temperature and high glass forming ability of the Au65Cu18Si17 BMG, high-energy X-ray diffraction (HEXRD) and Extended X-ray Absorption Fine Structure (EXAFS) measurements were carried out using synchrotron radiation. A sharp first peak and oscillation of the structure factor S(Q) up to the high wave number Q can be attributed to the dominant weighting factor of the Au-Au correlation over others. A reverse Monte Carlo (RMC) simulation was applied simultaneously to the HEXRD and EXAFS data. The obtained RMC model shows a quite highly dense packed structure with large amount of icosahedral type clusters around Au atoms while small ones around Si atoms. The partial Cu-Cu pair distribution function g Cu,Cu(r) shows a sharp peak at a short interatomic distance, i.e., 2.38 Å. The Cu-Cu pairs with short interatomic distances and the large thermal fluctuation around Cu atoms are considered to be one of the structural characteristics of the low glass transition temperature of the Au 65Cu18Si17 BMG.

Original languageEnglish
Pages (from-to)1351-1355
Number of pages5
JournalMaterials Transactions
Volume54
Issue number8
DOIs
Publication statusPublished - 2013

    Fingerprint

Keywords

  • Bulk metallic glass
  • Eutectic alloy
  • Glass transition
  • Gold-silicon based alloys
  • High energy X-ray diffraction
  • Reverse Monte Carlo simulation
  • X-ray absorption fine structure

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering
  • Mechanics of Materials

Cite this