Journal
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING
Volume 24, Issue 4, Pages -Publisher
IOP PUBLISHING LTD
DOI: 10.1088/0965-0393/24/4/045012
Keywords
superalloys; dislocation; impurity; EAM interatomic potential
Funding
- Thomas Young Centre-US Air Force Research Laboratory Collaboration - European Office of Aerospace Research and Development
- Engineering and Physical Sciences Research Council (EPSRC) [EP/L014742/1, EP/L027682/1]
- US Office of Naval Research Global
- DOE Office of Science User Facility [DE-AC02-06CH11357]
- Science Research Investment Fund
- EPSRC [EP/C523938/1, EP/L014742/1, EP/L027682/1] Funding Source: UKRI
- Engineering and Physical Sciences Research Council [EP/L027682/1, EP/C523938/1, EP/L014742/1] Funding Source: researchfish
Ask authors/readers for more resources
We present detailed comparisons between the results of embedded atom model (EAM) and density functional theory (DFT) calculations on defected Ni alloy systems. We find that the EAM interatomic potentials reproduce low-temperature structural properties in both the gamma and gamma' phases, and yield accurate atomic forces in bulk-like configurations even at temperatures as high as similar to 1200 K. However, they fail to describe more complex chemical bonding, in configurations including defects such as vacancies or dislocations, for which we observe significant deviations between the EAM and DFT forces, suggesting that derived properties such as (free) energy barriers to vacancy migration and dislocation glide may also be inaccurate. Testing against full DFT calculations further reveals that these deviations have a local character, and are typically severe only up to the first or second neighbours of the defect. This suggests that a QM/MM approach can be used to accurately reproduce QM observables, fully exploiting the EAM potential efficiency in the MM zone. This approach could be easily extended to ternary systems for which developing a reliable and fully transferable EAM parameterisation would be extremely challenging e.g. Ni alloy model systems with a W or Re-containing QM zone.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available