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Journal of Engineering Materials and Technology | Volume 131 | Issue 4 | PREDICTIVE SCIENCE AND TECHNOLOGY IN MECHANICS AND MATERIALS
PREDICTIVE SCIENCE AND TECHNOLOGY IN MECHANICS AND MATERIALS

Semi-Empirical Potential Methods for Atomistic Simulations of Metals and Their Construction Procedures

[+] Author and Article Information
Seong-Gon Kim1

Department of Physics and Astronomy, Center for Advanced Vehicular Systems, and Center for Computational Sciences, Mississippi State University, Mississippi State, MS 39762kimsg@hpc.msstate.edu

M. F. Horstemeyer

Center for Advanced Vehicular Systems, and Department of Mechanical Engineering, Mississippi State University, Mississippi State, MS 39762

M. I. Baskes

MST-8, MS G755, Los Alamos National Laboratory, Los Alamos, NM 87545

Masoud Rais-Rohani

Center for Advanced Vehicular Systems, and Department of Aerospace Engineering, Mississippi State University, Mississippi State, MS 39762

Sungho Kim, J. Houze, Amitava Moitra, Laalitha Liyanage

Department of Physics and Astronomy, and Center for Advanced Vehicular Systems, Mississippi State University, Mississippi State, MS 39762

B. Jelinek

Center for Advanced Vehicular Systems, Mississippi State University, Mississippi State, MS 39762

1

Corresponding author.

J. Eng. Mater. Technol 131(4), 041210 (Sep 01, 2009) (9 pages) doi:10.1115/1.3183784 History: Received March 10, 2009; Revised June 19, 2009; Published September 01, 2009
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General theory of semi-empirical potential methods including embedded-atom method and modified-embedded-atom method (MEAM) is reviewed. The procedures to construct these potentials are also reviewed. A multi-objective optimization (MOO) procedure has been developed to construct MEAM potentials with minimal manual fitting. This procedure has been applied successfully to develop a new MEAM potential for magnesium. The MOO procedure is designed to optimally reproduce multiple target values that consist of important material properties obtained from experiments and first-principle calculations based on density-functional theory. The optimized target quantities include elastic constants, cohesive energies, surface energies, vacancy-formation energies, and the forces on atoms in a variety of structures. The accuracy of the present potential is assessed by computing several material properties of Mg including their thermal properties. We found that the new MEAM potential shows a significant improvement over previously published potentials, especially for the atomic forces and melting temperature calculations.
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Figures

Grahic Jump Location
+The cohesive energies as a function of the lattice constant a for Mg atoms in hcp crystal structure compared with the ones obtained from the Rose equation. The data points are computed with the present MEAM potential while the curve is obtained from the Rose equation.
View Large  |  Save Figure  |  Download Slide (.ppt)
The cohesive energies as a function of the lattice constant a for Mg atoms in hcp crystal structure compared with the ones obtained from the Rose equation. The data points are computed with the present MEAM potential while the curve is obtained from the Rose equation.
Figure 1

The cohesive energies as a function of the lattice constant a for Mg atoms in hcp crystal structure compared with the ones obtained from the Rose equation. The data points are computed with the present MEAM potential while the curve is obtained from the Rose equation.

Grahic Jump Location
+The internal energies of Mg crystal in hcp structure as a function of temperature. The energies are obtained from the ensemble average of the MD simulations of five structures containing 448 Mg atoms.
View Large  |  Save Figure  |  Download Slide (.ppt)
The internal energies of Mg crystal in hcp structure as a function of temperature. The energies are obtained from the ensemble average of the MD simulations of five structures containing 448 Mg atoms.
Figure 2

The internal energies of Mg crystal in hcp structure as a function of temperature. The energies are obtained from the ensemble average of the MD simulations of five structures containing 448 Mg atoms.

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