Simulation of copper atom diffusion via the vacancy mechanism in a dilute Fe-Cu alloy.

Journal Article · Sat Jan 01 04:00:00 EST 2005 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.71.174205· OSTI ID:1003358

Arokiam, Alan ^[1]; Barashev, Aleksandr ^[1]; Bacon, David J ^[1]; Osetskiy, Yury N ^[2]

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1. University of Liverpool
2. ORNL

Atomic diffusion in pure {alpha}-Fe and Fe-l at.% Cu crystals via vacancies is investigated by molecular-dynamics computer simulation. In order to generate a large statistical set, modeling is performed for the temperature range of 1000-1800 K. The migration energy and preexponential factors in diffusion coefficients of copper and iron atoms are estimated and compared with the results of a five-frequency model, using different approaches for the frequencies, and Monte Carlo studies, where the energy barriers are obtained by molecular statics. It is concluded that the five-frequency model is valid. The vacancy-copper atom cross-diffusion coefficient is estimated by both molecular-dynamics and Monte Carlo methods and is concluded to be negative over the entire temperature range studied, indicating that under irradiation conditions copper atoms migrate in the direction opposite to the vacancy flux. It has been observed that, at temperatures above 1500 K, about 0.5% of the vacancy jumps are double jumps, when two atoms move simultaneously in a <111> direction towards the vacancy.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1003358
• Journal Information: Physical Review B, Journal Name: Physical Review B Journal Issue: 17 Vol. 71; ISSN 1098-0121; ISSN 1550-235X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ATOMS
COMPUTERIZED SIMULATION
COPPER
DIFFUSION
IRON
IRRADIATION
MONTE CARLO METHOD
SIMULATION
VACANCIES