TY - JOUR
T1 - Structural evolution of vacancy clusters in α -iron
T2 - A kinetic activation-relaxation technique study
AU - Rahman, Md Mijanur
AU - El-Mellouhi, Fedwa
AU - Mousseau, Normand
N1 - Publisher Copyright:
© 2023 American Physical Society.
PY - 2023/9
Y1 - 2023/9
N2 - The kinetics of vacancies in materials plays a significant role in determining their physical properties. In this work, we investigate diffusion of vacancies in α-iron using the kinetic activation-relaxation technique, an off-lattice kinetic Monte Carlo method with on-the-fly catalog building based on the activation-relaxation technique nouveau coupled with an embedded atom method potential. We focus on the evolution of one to eight vacancies to provide a detailed picture of the energy landscape, overall kinetics, and diffusion mechanisms associated with these defects. We show formation energies, activation barriers for the ground state of all eight systems, and migration barriers for the diffuse systems. This study points to an unsuspected dynamic richness, even for this simple system, that can only be discovered through comprehensive and systematic approaches such as the kinetic activation-relaxation technique. The complex energetic environment controlling the kinetics of small vacancy clusters, we find here, demonstrates that simple rules are not sufficient to develop a robust approach to predictive control and prevention of damage processes associated with vacancy clusters in structural metals.
AB - The kinetics of vacancies in materials plays a significant role in determining their physical properties. In this work, we investigate diffusion of vacancies in α-iron using the kinetic activation-relaxation technique, an off-lattice kinetic Monte Carlo method with on-the-fly catalog building based on the activation-relaxation technique nouveau coupled with an embedded atom method potential. We focus on the evolution of one to eight vacancies to provide a detailed picture of the energy landscape, overall kinetics, and diffusion mechanisms associated with these defects. We show formation energies, activation barriers for the ground state of all eight systems, and migration barriers for the diffuse systems. This study points to an unsuspected dynamic richness, even for this simple system, that can only be discovered through comprehensive and systematic approaches such as the kinetic activation-relaxation technique. The complex energetic environment controlling the kinetics of small vacancy clusters, we find here, demonstrates that simple rules are not sufficient to develop a robust approach to predictive control and prevention of damage processes associated with vacancy clusters in structural metals.
UR - http://www.scopus.com/inward/record.url?scp=85173011574&partnerID=8YFLogxK
U2 - 10.1103/PhysRevMaterials.7.093602
DO - 10.1103/PhysRevMaterials.7.093602
M3 - Article
AN - SCOPUS:85173011574
SN - 2475-9953
VL - 7
JO - Physical Review Materials
JF - Physical Review Materials
IS - 9
M1 - 093602
ER -