A Molecular Dynamics Study of Cu Segregation to the Σ11 Grain Boundary In Al

1996 ◽  
Vol 428 ◽  
Author(s):  
Hanchen Huang ◽  
T. Diaz de la Rubia ◽  
M. J. Fluss

AbstractWe present results of molecular dynamics (MD) simulation studies of Cu segregation to the Σ11 grain boundary (GB) in Al. The simulations were performed with Embedded Atom Method (EAM) potentials for Al and Al-Cu. The results predict that copper atoms tend to order along either side of the interface even at the pure symmetrical GB, forming alternating chains along the direction. The nucleation of the chains is driven by a change in the local atomic level stress induced by the pre-existing Cu atoms at the GB.

2020 ◽  
Vol 978 ◽  
pp. 436-445
Author(s):  
Mouparna Manna ◽  
Snehanshu Pal

In this present study, molecular dynamics (MD) simulation has been performed to investigate the influence of applied hydrostatic compressive and tensile pressure on glass forming process of Ni62Nb38 bimetallic glass using embedded atom method (EAM). During fast cooling (~10 K ps-1), tensile and compressive pressure has been applied having 0.001 GPa,0.01 GPa and 0.1 GPa magnitude. The glass transition temperature (Tg) for each pressurized (Tensile and Compressive nature) cooling case has been calculated and Tg is found to be dependent on both magnitude and nature of the pressure applied during cooling process.Voronoi cluster analysis has also been carried out to identify the structural evaluation during hydrostatically pressurised fast cooling process. In case of both hydrostatic tensile and compressive pressurised cooling processes, Tgincreases with the increase of pressure from 0.001 GPa to 0.1 GPa in magnitude.


2013 ◽  
Vol 592-593 ◽  
pp. 55-58 ◽  
Author(s):  
Dmitrij Sergeevich Kryzhevich ◽  
Aleksandr Vyacheslavovich Korhuganov ◽  
Konstantin Petrovich Zolnikov ◽  
Sergei Grigorievich Psakhye

Molecular dynamics investigation of metal crystallite with bcc lattice under nanoindentation was carried out. Potentials of interatomic interactions were calculated on the base of the approximation of the embedded atom method. The potentials chosen make it possible to describe with a high accuracy the elastic and surface properties of the simulated metal and energy parameters of defects, which is important for solution of the task posed in the work. For clarity and simpler indentation data interpretation, an extended cylindrical indenter was used in the investigation and loading was realized by its lateral surface. The simulated crystallite had a parallelepiped shape. The loaded plane of crystallite was modeled as a free surface while the positions of atoms in the opposite plane of crystallite were fixed along the indentation direction. Other planes of crystallite were simulated as free surfaces. The indenter velocity varied from 5 to 25 m/s in different calculations. The loading of the model crystallite was realized at 300 K. Influence of interfaces (free surfaces and grain boundaries) on peculiarities of plastic deformation nucleation and interactions of generated structural defects with interfaces in simulated crystallite under nanoindentation were investigated.


Open Physics ◽  
2006 ◽  
Vol 4 (4) ◽  
Author(s):  
Yasemin Çiftci ◽  
Kemal Çolakoğlu ◽  
Sefa Kazanç ◽  
SonerÖzgen

AbstractThis paper describes the effect of pressure on some the mechanical properties of transition metals Cu, Ag, and Au, such as elastic constants and bulk modulus. Using molecular dynamics (MD) simulation, the present study was carried out using the modified many-body Morse potential function expression in the framework of the Embedded Atom Method (EAM). The effect of pressure on equilibrium volume, elastic constants, and bulk modulus were determined, and found to be in agreement with other theoretical calculations and experimental data.


1990 ◽  
Vol 202 ◽  
Author(s):  
M. Karimi ◽  
P. Tibbits ◽  
D. Ila ◽  
I. Dalins ◽  
G. Vidali

ABSTRACTIsothermal-isobaric Molecular Dynamics (MD) simulation of a submonolayer Pb film in c(2×2) ordered structure adsorbed on a Cu(100) substrate showed retention of order to high T. The Embedded Atom Method (EAM) calculated the energy of atoms of overlayer and substrate. The time-averaged squared modulus of the two dimensional structure factor for the Pb overlayer measured the order of the overlayer. The results are for increasing T only, and require verification by simulated cooling.


2021 ◽  
Author(s):  
Karthik Narayan

This thesis presents a powerful numerical fitting procedure for generating Embedded Atom Method (EAM) inter-atomic potentials for pure Face Centred Cubic (FCC) and Body Centred Cubic (BCC) metals. The numerical fitting procedure involves assuming a reasonable parameterized form for a portion of the EAM potential, and then fitting the remaining portion to select thermal and elastic properties of the metal. Molecular Dynamics (MD) simulation is used to effect the fitting procedure. The procedure is used to generate an EAM potential for copper, an FCC metal. This resulting EAM potential is used to conduct MD simulations of perfect copper crystals containing voids of different geometries. Following this, a bridged Finite Element-Molecular Dynamics (FE-MD) method is presented, which can be used to simulate large atomic systems much more efficiently than MD simulation alone. The method implements a novel element discretization scheme proposed by the author that is so general that it can be applied to any system of objects interacting with each other via any potential (simple or complex, EAM or otherwise). This bridged FE-MD method is used to reanalyze the voids in the copper crystal lattice. The resulting virial stress increment patterns are found to agree remarkably with the earlier MD simulation results. Furthermore, the bridged FE-MD method is much quicker than the pure MD simulation. These two facts prove the power and usefulness of the bridged FE-MD method, and validate the proposed element discretization scheme


2019 ◽  
Vol 87 (3) ◽  
pp. 31301 ◽  
Author(s):  
Hicham El Azrak ◽  
Abdessamad Hassani ◽  
Abdelhadi Makan ◽  
Fouad Eddiai ◽  
Khalid Sbiaai ◽  
...  

In this paper, molecular dynamics (MD) simulation of surface morphology during homoepitaxial growth of Copper was investigated. For this purpose, simulations of Cu deposition on the Cu(111) substrate with an incidence energy of 0.06 eV at 300K were performed using the embedded-atom method (EAM). The grown thin film on Cu(111) reveled a rough surface morphology. During deposition, the important fraction of atoms intended for the upper layers undergone a rising rate of about 40% starting from the 2nd period and continued to increase until 65%, while the lower level reached a permanent rate of only 25% by the 4th period. Otherwise, except at the first layer level, the lower layers are incomplete. This void in the lower layers has favored the growth of the upper layers until a rate of 143% and has accelerated their time appearance. Th incidence energy has favored the filling of lower layers by reducing this surface roughness. However, the temperature effect needs more relaxation time to fill the lower layers.


2009 ◽  
Vol 1224 ◽  
Author(s):  
Yoshiaki Kogure ◽  
Toshio Kogugi ◽  
Tadatoshi Nozaki ◽  
Masao Doyama

AbstractAtomistic configuration and motion of dislocation have been simulated by means of molecular dynamics method. The embedded atom method potential for copper is adopted in the simulation. Model crystal is a rectangular solid containing about 140,000 atoms. An edge dislocation is introduced along [112] direction near the center of model crystal, and the system is relaxed. After the dislocation configuration is stabilized, a shear stress is applied and released. Wavy motion of dislocation is developed on the Peierls valleys when the free boundary condition is adopted. Motion of pinned dislocation is also simulated.


1995 ◽  
Vol 10 (7) ◽  
pp. 1589-1592 ◽  
Author(s):  
Chun-Li Liu ◽  
S.J. Plimpton

Molecular dynamics (MD) simulations of diffusion in a Σ5(310) [001] Al tilt grain boundary were performed using for the first time three different potentials based on the embedded atom method (EAM). The EAM potentials that produce more accurate melting temperatures also yield activation energies in better agreement with experimental data. Compared to pair potentials, the EAM potentials also give more accurate results.


2007 ◽  
Vol 539-543 ◽  
pp. 3546-3550 ◽  
Author(s):  
Sung Hoon Lee ◽  
Sang Soo Han ◽  
Jeung Ku Kang ◽  
Hyuck Mo Lee

The molecular dynamics (MD) simulation employing the embedded atom method (EAM) has been performed to examine the phase stability of Pt nanoclusters, Ptn (n=38, 147, 309 and 561 atoms) with size and temperature. From heating and freezing curves of the nanoclusters, the clusters (Pt147, Pt309 and Pt561) larger than 1 nm in size showed an icosahedral morphology near 460 ~ 660 K during freezing, where the formation energy of the icosahedral phase is 0.051 eV/atom for Pt147, 0.056eV/atom for Pt309 and 0.067 eV/atom for Pt561. We also investigated coalescence between two Pt nanoclusters and observed that the minimum size of the coalescent one is around 1 nm at 673 K.


1988 ◽  
Vol 141 ◽  
Author(s):  
J. F. Lutsko ◽  
D. Wolf ◽  
S. R. Phillpot

AbstractThe behavior of a metallic grain boundary at high temperatures is studied using an embedded atom potential. A recently developed molecular dynamics code is used which allows the simulation of an isolated grain boundary at temperatures as high as the bulk melting point. The stability of the boundary below the melting point is studied and compared with earlier investigations which have suggested the existence of a “premelting“ transition. It is found that the boundary migrates at high temperature but remains well defined up to the bulk melting point. In contrast to simulations of ideal crystals, it was not possible to superheat the grain boundary due to the nucleation of bulk melting at the boundary.


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