Get access

Intrinsically Ductile Failure in a Nanocrystalline Beta Titanium Alloy

Authors

  • Wei Xu,

    Corresponding author
    1. Department of Mechanical Engineering and ARC Centre of Excellence for Design in Light Metals, University of Melbourne, Victoria 3010, (Australia)
    • Department of Mechanical Engineering and ARC Centre of Excellence for Design in Light Metals, University of Melbourne, Victoria 3010, (Australia)
    Search for more papers by this author
  • Roberto B. Figueiredo,

    1. Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, Belo Horizonte, MG 31270-901, (Brazil)
    Search for more papers by this author
  • Xiaolin Wu,

    1. Department of Mechanical Engineering and ARC Centre of Excellence for Design in Light Metals, University of Melbourne, Victoria 3010, (Australia)
    Search for more papers by this author
  • Simon Pauly,

    1. Institut für Komplexe Materialien, IFW Dresden, Helmholtzstraβe 20, D-01069 Dresden, (Germany)
    Search for more papers by this author
  • Mihai Stoica,

    1. Institut für Komplexe Materialien, IFW Dresden, Helmholtzstraβe 20, D-01069 Dresden, (Germany)
    Search for more papers by this author
  • Jürgen Eckert,

    1. Institut für Komplexe Materialien, IFW Dresden, Helmholtzstraβe 20, D-01069 Dresden, (Germany)
    2. Institut für Werkstoffwissenschaft, TU Dresden, D-01062 Dresden, (Germany)
    3. Materials Research Group, School of Engineering Sciences, University of Southampton, Southampton SO17 1BJ, (UK)
    4. Departments of Aerospace and Mechanical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-1453, (USA)
    Search for more papers by this author
  • Terence G. Langdon,

    1. Materials Research Group, School of Engineering Sciences, University of Southampton, Southampton SO17 1BJ, (UK)
    2. Departments of Aerospace and Mechanical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-1453, (USA)
    Search for more papers by this author
  • Kenong Xia

    Corresponding author
    1. Department of Mechanical Engineering and ARC Centre of Excellence for Design in Light Metals, University of Melbourne, Victoria 3010, (Australia)
    • Department of Mechanical Engineering and ARC Centre of Excellence for Design in Light Metals, University of Melbourne, Victoria 3010, (Australia)
    Search for more papers by this author

  • Support is gratefully acknowledged from the Australian Research Council, the AvH Foundation, the German Science Foundation, and the National Science Foundation of the United States (Grant No. DMR-0855009).

Abstract

A nanocrystalline bcc Ti67.4Nb24.6Zr5Sn3 alloy is shown to fracture in an intrinsically ductile manner with exceptionally large dimples (up to 10 µm) which are two orders of magnitude greater than the grain size (≈ 40 nm). This large plasticity length scale is attributed to a combination of low shear modulus (≈ 27 GPa), high Poisson's ratio (≈ 0.4) and ultrahigh strength (UTS ≈ 1.1 GPa), close to the ideal shear stress, which facilitates ideal shear deformation to promote transgranular shear.

Ancillary