Molecular dynamics modeling melting of of aluminum nanoparticles of the embedded atom method

AbstractThe dynamic fracture (spallation) of ductile metals is known to initiate through the nucleation and growth of microscopic voids. Here, we apply atomistic molecular dynamics modeling to the early growth of nanoscale (2nm radius) voids in face centered cubic metals using embedded atom potential models. The voids grow through anisotropic dislocation nucleation and emission into a cuboidal shape in agreement with experiment. The mechanism of this nucleation process is presented. The resulting viscous growth exponent at late times is about three times larger than expected from experiment for microscale voids, suggesting either a length scale dependence or a inadequacy of the molecular dynamics model such as the perfect crystal surrounding the void.

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Molecular Dynamics Modeling of Thermal Transport in Damaged Continua

2008 Second International Conference on Integration and Commercialization of Micro and Nanosystems ◽

10.1115/micronano2008-70070 ◽

2008 ◽

Author(s):

Navin Kumar ◽

Kishore Pochiraju

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Dynamics Modeling ◽

Damage State ◽

Damage Propagation ◽

Embedded Atom ◽

Solid Gold ◽

Change Behavior ◽

Molecular Dynamics Modeling ◽

Atomic Interactions

The interaction between the damage state and the thermal conductivity is studied in this paper. The damage propagation and the effective thermal conductivity of the damaged continuum is studied using equilibrium molecular dynamics (EMD) method based on the Green-Kubo relation. A solid gold lattice is considered and the damage is initiated and propagated by stretching two opposite ends while system is maintained at constant volume, constant temperature (NVT) condition. Both Lennard-Jones (LJ) 6–12 and embedded-atom method (EAM) potentials are used to model the inter-atomic interactions. Results are presented illustrating the load-displacement relationship during damage growth and the thermal conductivity change behavior for a selected crack length.

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Molecular dynamics modeling and simulation of lubricant between sliding solids

Journal of Micromechanics and Molecular Physics ◽

10.1142/s2424913017500096 ◽

2017 ◽

Vol 02 (02) ◽

pp. 1750009 ◽

Cited By ~ 4

Author(s):

Mir Ali Ghaffari ◽

Yan Zhang ◽

Shaoping Xiao

Keyword(s):

Modeling And Simulation ◽

Hydrodynamic Lubrication ◽

Molecular Model ◽

Embedded Atom Method ◽

Dynamics Modeling ◽

Crystal Lattices ◽

Jones Potential ◽

Cubic Crystal ◽

Embedded Atom ◽

Molecular Dynamics Modeling

This paper presents molecular dynamic modeling and simulation of lubricant between sliding solids. Linear [Formula: see text]-alkanes with united atoms were used to model lubricant while iron sliding solids were modeled with body-centered cubic crystal lattices. We employed various potential functions, including the embedded atom method, the multibody force field and the Lennard–Jones potential, to approximate the interatomic interactions in the molecular model. Hydrodynamic lubrication was considered in this paper. We found that the temperature and the chain length of alkanes had effects on the friction between lubricated sliding solids. In addition, one debris, modeled as a nanoparticle, was added in the lubricant to study its effect on the friction. It was observed that nanoparticles would increase the friction in hydrodynamic lubrication.

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