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 language | English |
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Pages (from-to) | 1943-1956 |
Number of pages | 14 |
Journal | Journal of Materials Research |
Volume | 30 |
Issue number | 12 |
DOIs | |
Publication status | Published - 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