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Showing 1 to 18 of 18 for “"molecular statics"”.
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Molecular Statics Simulation in Aluminum
… toughness in aluminum were studied by using the Molecular Statics Technique with atomic interactions described in terms of the Embedded Atom Method. It was found that aluminum is a ductile material in which the cracks generate dislocations, blunting the cracks. The blunting and the dislocation …
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High Performance Computing Issues in Large-Scale Molecular Statics Simulations
… to meeting these challenges in the context of a Molecular Statics code. We describe sequential and parallel optimizations made to the code and also a suite of tools constructed to facilitate the execution of the Molecular Statics program on a network of parallel machines with the aim of …
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Atomistic studies on irradiation damage in iron
… induced by radiation have been simulated using molecular dynamics (MD). The number and type of defects produced are compared for pure iron and iron with a small hydrogen concentration. Second, the inter- action energy between point defects and line dislocations has been calculated for a number …
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Simulation of Bulk and Grain Boundary Diffusion in B2 NiAl
Molecular dynamics simulations of the diffusion process in ordered B2 compounds at high temperature were performed using an embedded atom interatomic potential developed to fit NiAl properties. Diffusion in the bulk occurs through a variety of cyclic mechanisms that accomplish the motion of the …
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Development of Kinetic Monte Carlo Code to Study Oxygen Mobility in Lanthanum-doped Ceria
… confirm the so-called lanthanum trapping effect. Molecular Statics simulations were performed using interatomic potentials for cerium oxide provided by Gotte et al., Minervini et al. and Sayle et al. to calculate local configuration-dependent oxygen vacancy migration energies. Kinetic Monte Carlo …
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Atomistic simulation of deformation induced rotation in Cu-Nb composites
… (Cu-Nb) nano-composite models is simulated using molecular statics techniques to assess the rotational stability of Cu-Nb interfaces at high strains up to 90% thickness reduction. Crystals strain and rotate under compression, and certain Cu-Nb composites have been shown to reach a steady state of …
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Computer simulation of defect evolution in lanthanum doped cerium dioxide under irradiation
… or mixed oxide fuel (MOX), is developed for both molecular statics (MS) and molecular dynamics (MD) simulations. Then the single xenon incorporation and migration behaviors in ceria are examined using MS calculation. Although the vacancy cluster with only one cerium vacancy is found to be a stable …
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Grain boundary studies in ordered intermetallic compound Ni3 Al
… atomistic computer simulations, namely, molecular statics simulation and two dimensional lattice gas model, were carried out. Both results showed a similar trend of disordering near the grain boundary regardless of grain boundary composition and atomic interaction energy assumptions. …
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Defect Structures in Ordered Intermetallics; Grain Boundaries and Surfaces in FeAl, NiAl, CoAl and TiAl
… and <I>L</I>1₀ γ-TiAl were investigated using molecular statics and embedded atom potentials in order to explore general trends for a series of B2 compounds as well as TiAl. The potentials used correctly predict the proper mechanism of compositional disorder of these compounds. Using these …
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Mechanisms of Deformation and Fracture in TiAl: An Atomistic Simulation Study
… with point defects in the lattice. We use the molecular statics technique with atomic interactions described in terms of the embedded atom method. We simulate the crack propagation along (100), (001), (110) and (111) planes in TiAl. The cleavage along (100) and (001) planes shows purely brittle …
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Deformation mechanisms in B2 aluminides: shear faults and dislocation core structures in FeAl, NiAl, CoAl and FeNiAl
… to better understand this lack of ductility, molecular statics simulations of planar fault defects and dislocation core structures were conducted in a series of B2 aluminides with increasing ordering energy (FeAl, NiAl, CoAl). The simulation results in NiAl were compared with in-situ straining …
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Study of Nanowires Using Molecular Dynamics Simulations
… nanoscale effects. Three-dimensional atomistic molecular dynamics studies were performed for each sample using the super computer System X located at Virginia Tech. Thermal grain growth simulations were performed on 4 nm grain size nc-Ni by observing grain sizes over time for temperatures from …
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Plastic Deformation in Complex Crystal Structures
… with a Peierls dislocation configuration and a molecular statics energy calculation. A simple model built electrostatic and Lennard-Jones interactions was used for the rocksalt structure, this model was found to describe the hard slip system well, but was insufficient to describe the softer slip …
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Multiscale modeling and analysis of nanofibers and nonwoven materials
… a framework to model the nonwoven mats. First, molecular dynamics (MD) simulations are used to investigate the properties of polymeric nanofibers. The fibers consist of chains that mimic the prototypical polymer polyethylene that have diameters in the range 1.9-23.0 nm. We analyzed these …
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Modeling of plastic deformation due to slip-its implications in characterizing fatigue crack growth thresholds and non-Schmid behavior in transforming alloys
… grain/twin boundaries within the framework of Molecular Dynamics and characterized the on-going dislocation reactions as well as the crystalline resistance at the boundary against the glide of dislocations participating in these reactions. Subsequently, the effective threshold stress intensity …
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Modeling of Effect of Alloying Elements on Radiation Damage in Metallic Alloys
… damage in iron-based metallic. Systematic molecular dynamics simulations were conducted to study the alloying element effects on the primary damage in Fe-based alloys, including defect production and dislocation loop transformations, and their connections with defect thermodynamics. First, …
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A new age of fuel performance code criteria studied through advanced atomistic simulation techniques
A fundamental step in understanding the effects of irradiation on metallic uranium and uranium dioxide ceramic fuels, or any material, must start with the nature of radiation damage on the atomic level. The atomic damage displacement results in a multitude of defects that influence the fuel …
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Molecular Dynamics Investigation on the Fracture Behavior of Nanocrystalline Fe
Crack propagation studies in nanocrystalline alpha-iron samples with grain sizes ranging from 6 to 12 nm are reported at temperatures ranging from 100K to 600K using atomistic simulations. For all grain sizes, a combination of intragranular and intergranular fracture is observed. Mechanisms such as …