Modeling of supersonic crowdion clusters in FCC lattice: Effect of the interatomic potential

Among a wide variety of point defects, crowdions can be distinguished by their high energy of formation and relatively low migration barriers, which makes them an important agent of mass transfer in lattices subjected to severe plastic deformation, irradiation, etc. It was previously shown that complexes and clusters of crowdions are even more mobile than single interstitials, which opened new mechanisms for the transfer of energy and mass in materials under intense external impacts. One of the most popular and convenient methods for analyzing crowdions is molecular dynamics, where the results can strongly depend on the interatomic potential used in the study. In this work, we compare the characteristics of a crowdion in an fcc lattice obtained using two different interatomic potentials — the pairwise Morse potential and the many-body potential for Al developed by the embedded atom method. It was found that the use of the many-body potential significantly affects the dynamics of crowdion propagation, including the features of atomic collisions, the evolution of energy localization and the propagation path.

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Self Diffusion and Activation Energy of Liquid Palladium

International Journal of Modern Physics C ◽

10.1142/s0129183197001089 ◽

1997 ◽

Vol 08 (06) ◽

pp. 1217-1221 ◽

Cited By ~ 6

Author(s):

J. I. Akhter ◽

K. Yaldram

Keyword(s):

Activation Energy ◽

Molecular Dynamics ◽

Embedded Atom Method ◽

Many Body ◽

Fcc Metals ◽

Self Diffusion ◽

Embedded Atom ◽

The Many ◽

Body Potential ◽

Self Diffusion Coefficient

Molecular dynamics studies of the temperature dependence of self diffusion coefficient of palladium has been carried out using the many body potential generated by the Embedded Atom Method of Daw and Baskes. These values as well as the results for activation energy are compared with similar results for other fcc metals.

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Defect Cluster Formation in High Energy Displacement Cascades in Copper

MRS Proceedings ◽

10.1557/proc-650-r4.2 ◽

2000 ◽

Vol 650 ◽

Cited By ~ 3

Author(s):

Yuri N. Osetsky ◽

David J. Bacon

Keyword(s):

Cluster Formation ◽

Pair Potential ◽

Simulation Method ◽

High Energy ◽

Interatomic Potentials ◽

Dislocation Loops ◽

Many Body ◽

Displacement Cascades ◽

Stacking Fault Tetrahedra ◽

Body Potential

ABSTRACTPrimary radiation damage in displacement cascades in metals has been studied extensively by atomistic simulation during the last decade. The variety of defect types observed in cascade simulation is not entirely consistent with experimental data. For example, experiments on copper show a very effective production of stacking fault tetrahedra (SFTs) but this was not observed systematically in cascade simulation. To clarify this and related issues, extensive simulation of displacement cascades in copper have been performed using two different interatomic potentials, a short-range many-body potential and a long-range pair potential. We have studied the damage created by primary knock-on-atoms of energy up to 20keV, i.e. below the energy range for formation of subcascades, at temperatures 100 and 600K. Special attention was paid to cascade statistics and the accuracy of simulation in the collision stage. The former required many simulations for each temperature whereas the latter involved a modification of the simulation method. The results on variety of clusters observed, e.g. SFTs, glissile and sessile interstitial clusters, and faulted and perfect interstitial dislocation loops, lead to conclusions on the effect of the potentials and the significant variation of the number of Frenkel pairs and clustering effects produced in different cascades under the same conditions.

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Accurate Interatomic Potentials for Ni, Al and Ni3Al

MRS Proceedings ◽

10.1557/proc-82-175 ◽

1986 ◽

Vol 82 ◽

Cited By ~ 472

Author(s):

Arthur F. Voter ◽

Shao Ping Chen

Keyword(s):

Interatomic Potential ◽

Alloy System ◽

Atomistic Simulations ◽

Al Alloy ◽

Interatomic Potentials ◽

Many Body ◽

Fitting Procedure ◽

Crack Tips ◽

Computational Dependence ◽

Body Potential

ABSTRACTTo obtain meaningful results from atomistic simulations of materials, the interatomic potentials must be capable of reproducing the thermodynamic properties of the system of interest. Pairwise potentials have known deficiencies that make them unsuitable for quantitative investigations of defective regions such as crack tips and free surfaces. Daw and Baskes [Phys. Rev. B 29, 6443 (1984)] have shown that including a local “volume” term for each atom gives the necessary many-body character without the severe computational dependence of explicit n-body potential terms. Using a similar approach, we have fit an interatomic potential to the Ni3Al alloy system. This potential can treat diatomic Ni2, diatomic Al2, fcc Ni, fcc Al and L12 Ni3Al on an equal footing. Details of the fitting procedure are presented, along with the calculation of some properties not included in the fit.

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Dislocation Generation and Crack Propagation in Metals Examined in Molecular Dynamics Simulations

MRS Proceedings ◽

10.1557/proc-278-173 ◽

1992 ◽

Vol 278 ◽

Cited By ~ 6

Author(s):

J. A. Rifkin ◽

C. S. Becquart ◽

D. Kim ◽

P. C. Clapp

Keyword(s):

Crack Propagation ◽

Atomistic Simulations ◽

Many Body ◽

Dislocation Generation ◽

Embedded Atom ◽

Stress Levels ◽

Different Temperatures ◽

The Many ◽

Dynamics Simulations ◽

Many Body Interactions

AbstractWe have carried out a series of atomistic simulations on arrays of about 10,000 atoms containing an atomically sharp crack and subjected to increasing stress levels. The ordered stoichiometric alloys B2 NiAl, B2 RuAl and A15 Nb3AI have been studied at different temperatures and stress levels, as well as the elements Al, Ni, Nb and Ru. The many body interactions used in the simulations were derived semi-empirically, using techniques related to the Embedded Atom Method. Trends in dislocation generation rates and crack propagation modes will be discussed and compared to experimental indications where possible, and some of the simulations will be demonstrated in the form of computer movies.

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Свойства движущихся дискретных бризеров в бериллии

Физика твердого тела ◽

10.21883/ftt.2018.05.45798.334 ◽

2018 ◽

Vol 60 (5) ◽

pp. 978

Author(s):

O.B. Бачурина ◽

P.T. Мурзаев ◽

A.C. Семенов ◽

E.A. Корзникова ◽

C.B. Дмитриев

Keyword(s):

Energy Transport ◽

Interatomic Potential ◽

Maximum Velocity ◽

Face Centered Cubic ◽

Sound Waves ◽

Many Body ◽

Hexagonal Close Packed ◽

Bcc Lattice ◽

Face Centered ◽

The Many

AbstractDiscrete breathers (DBs) have been described among pure metals with face-centered cubic (FCC) and body-centered cubic (BCC) lattice, but for hexagonal close-packed (HCP) metals, their properties are little studied. In this paper, the properties of standing and moving DBs in beryllium HCP metal are analyzed by the molecular dynamics method using the many-body interatomic potential. It is shown that the DB is localized in a close-packed atomic row in the basal plane, while oscillations with a large amplitude along the close-packed row are made by two or three atoms, moving in antiphase with the nearest neighbors. Dependences of the DB frequency on the amplitude, as well as the velocity of the DB on its amplitude and on parameter δ, which determines the phase difference of the oscillations of neighboring atoms, are obtained. The maximum velocity of the DB movement in beryllium reaches 4.35 km/s, which is 33.7% of the velocity of longitudinal sound waves. The obtained results supplement our concepts about the mechanisms of localization and energy transport in HCP metals.

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ATOMISTIC SCALE SIMULATION OF TEXTURED SURFACES ON DRY SLIDING FRICTION

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2013-0079 ◽

2013 ◽

Vol 37 (3) ◽

pp. 927-936 ◽

Cited By ~ 4

Author(s):

Ming-Yuan Chen ◽

Zheng-Han Hong ◽

Te-Hua Fang ◽

Shao-Hui Kang ◽

Li-Min Kuo

Keyword(s):

Sliding Friction ◽

Surface Texturing ◽

Dynamics Simulation ◽

Embedded Atom Method ◽

Textured Surface ◽

Textured Surfaces ◽

Many Body ◽

Embedded Atom ◽

Modified Embedded Atom Method ◽

Body Potential

Fe sliding on a Fe substrate with surface texturing is investigated using molecular dynamics simulation. The modified embedded-atom method many-body potential is used to describe the interaction of Fe atoms. The tribological properties of surface texturing during nanosliding are discussed. Results indicate that a textured surface has lower friction than that of a flat surface. In addition, a surface with parallel grooves has lower friction than that of a dimpled surface. Hence, surface texturing greatly affects friction.

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Effects of Angular Dependent Terms in the Interatomic Potential on Defect Properties in TiAl

MRS Proceedings ◽

10.1557/proc-364-151 ◽

1994 ◽

Vol 364 ◽

Cited By ~ 3

Author(s):

Julia Panova ◽

Diana Farkas

Keyword(s):

Interatomic Potential ◽

Stacking Faults ◽

Core Structure ◽

Interatomic Potentials ◽

The Core ◽

Embedded Atom ◽

Dependent Term

AbstractInteratomic potentials of the Embedded Atom and Embedded Defect types were used to study the effect of the angular dependent term in the Embedded Defect potential on the properties of defects in TiAl. The defect properties were computed with interatomic potentials developed with and without angular dependent terms. It was found that the inclusion of the angular dependent terms tends to increase the energies of the APB’s and lower the energies of stacking faults. The effects of the angular term on the relaxation around vacancies and antisites in TiAl was also studied, as well as the core structure of several dislocations in this compound.

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Interatomic Forces and Bonding Mechanisms in MgO Clusters

MRS Proceedings ◽

10.1557/proc-193-21 ◽

1990 ◽

Vol 193 ◽

Cited By ~ 3

Author(s):

Nancy F. Wright ◽

Gayle S. Painter

Keyword(s):

Interatomic Potentials ◽

Many Body ◽

Restoring Force ◽

Mechanical Study ◽

Quantum Mechanical Study ◽

Force Curves ◽

The Many ◽

Quantum Treatment ◽

Oxygen Ratio

ABSTRACTWe report results from a first-principles local spin density quantum mechanical study of the energetics and elastic properties of a series of magnesium-oxygen clusters of various morphologies. The role of quantum effects, e.g. covalency, in the bonding character of diatomic MgO is determined by comparison of classical and quantum restoring force curves. The dependence of binding properties on geometry and metal to oxygen ratio is determined by comparison of binding energy curves for a series of clusters. Results show that while gross features of the binding curves may be represented by simple interatomic potentials, details require the many body corrections of a full quantum treatment.

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