Self-organization of Cu-Ag during controlled severe plastic deformation at high temperatures

Salman N. Arshad, Timothy G. Lach, Julia Ivanisenko, Daria Setman, Pascal Bellon, Shen J. Dillon (Corresponding author), Robert S. Averback

Publications: Contribution to journalArticlePeer Reviewed

Abstract

Cu 90Ag 10 alloys were subjected to severe plastic deformation at temperatures ranging from 25 to 400 °C and strain rates ranging from 0.1 to 6.25 s -1 using high-pressure torsion. The deformed samples were characterized by x-ray diffraction, transmission electron microscopy, and atom-probe tomography. A dynamic competition between shear-induced mixing and thermally activated decomposition led to the self-organization of the Cu-Ag system at length scales varying from a few atomic distances at room temperature to ≈50 nm at 400 °C. Steady-state microstructural length scales were minimally affected by varying the strain rate, although at 400 °C, the grain morphology did depend on strain-rate. Our results show that diffusion below 300 °C is dominated by nonequilibrium vacancies, and by comparison with previous Kinetic Monte Carlo simulations [D. Schwen et al., J. Mater. Res. 28, 2687-2693 (2013)], their concentration could be obtained.

Original languageEnglish
Pages (from-to)1943-1956
Number of pages14
JournalJournal of Materials Research
Volume30
Issue number12
DOIs
Publication statusPublished - Jun 2015

Austrian Fields of Science 2012

  • 103018 Materials physics

Keywords

  • HIGH-PRESSURE TORSION
  • SUPERSATURATED SOLID-SOLUTIONS
  • MECHANICAL-PROPERTIES
  • IMMISCIBLE ALLOYS
  • LENGTH SCALE
  • METALS
  • SYSTEMS
  • POWDERS
  • HEAT
  • FE
  • Ag
  • Cu
  • mechanical alloying

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