Atomic Dynamics in Metallic Liquids and Glasses

نویسندگان

  • T. Egami
  • V. Levashov
  • R. S. Aga
  • J. R. Morris
چکیده

How atoms move in metallic glasses and liquids is an important question in discussing atomic transport, glass formation, structural relaxation and other properties of metallic glasses. While the concept of free-volume has long been used in describing atomic transport, computer simulations and isotope measurements have shown that atomic transport occurs by a much more collective process than assumed in the free-volume theory. We introduce a new approach to describe the atomic dynamics in metallic glasses, in terms of local energy landscapes related to fluctuations in the topology of atomic connectivity. This approach may form the basis for a new paradigm for discussing the structureproperties relationship in metallic glasses. [doi:10.2320/matertrans.MJ200763]

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تاریخ انتشار 2007