Published September 15, 2007 | Version v1
Journal article

Growth mechanism from nano-ordered clusters to nanocrystals in a deeply undercooled melt of Zr-Ni-Ti metallic glass

  • 1. Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Tennessee 37996-2200 (United States)
  • 2. Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China)
  • 3. Department of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210014 (China)
  • 4. State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China)

Description

Both experimental studies and molecular dynamics (MD) simulations reveal a unique atomic-scale growth mechanism during crystallization of an amorphous alloy Zr65Ni25Ti10. By using a high-resolution transmission electron microscope incorporated with nanobeam diffraction technique, we have clearly seen imperfect ordered packing of nano-ordered clusters (NOCs) with a size of 1-2 nm embedded in this amorphous material. Under a very large undercooling condition, NOCs essentially act as preexisting nuclei that can grow directly into nanocrystals during annealing treatments. The growth mechanism includes three distinct steps in succession: formation of quasi-ordered structure with one-dimensional (1D) periodicity, and then 2D periodicity, and finally forming 3D nanocrystals. These three growth steps are cross-linked, and atomic movements are also accommodated by a rotation of atomic planes. This growth mechanism is unambiguously verified by MD simulation

Additional details

Identifiers

Publishing Information

Journal Title
Journal of Applied Physics
Journal Volume
102
Journal Issue
6
Journal Page Range
p. 063515-063515.5
ISSN
0021-8979
CODEN
JAPIAU

Optional Information

Notes
(c) 2007 American Institute of Physics