Towards Multiscale Modeling of Metals via Embedded Particle Computer Simulation

Abstract

Abstract. The embedded atom method is adapted to study solid friction and the mechanical behavior of a model metal which incorporates the effect of electronic glue in its structure. The elastic properties of real metals are reproduced by a set of basic model potentials as revealed by analytic considerations. A slightly modified version of a classical nonequilibrium molecular dynamics computer simulation is employed to study the dynamics and structural changes of the model metal undergoing a process of solid friction and an uniaxial compression in order to analyze, e.g., plastic yield, transient friction coefficients, and the underlying structure. Under the appropriate choice of parameters, the model turns out to also be applicable for studying multiscale structures in porous metals.

Flow Properties Inferred from Generalized Maxwell Models

“…The time dependence of the shear stress is qualitatively similar to that one found in NEMD computer simulations for the plastic flow of solids and in sliding friction [39,40]. The friction force observed in experiments shows a similar behaviour [43].…”

“…Plastic flow and shear-induced melting occur in solid friction processes. These phenomena have been studied in Non-Equilibrium-Molecular-Dynamics (NEMD) computer simulations [39,40]. The present theory provides a generic model for the flow of solids.…”

A numerical study of the SPH method for simulating transient viscoelastic free surface flows

“…Since its invention, it has been extensively studied, extended and applied in many areas such as the dynamic response of elasto-plastic materials [18][19][20], free surface flows [21], low-Reynolds number viscous flows [22][23][24], solid friction [25], incompressible fluids [26,27], heat transfer [28], multi-phase flows [29,30], geophysical flows [31][32][33] and turbulence modeling [34]. Solid friction has often been studied using embedded atom methods, a method very similar in spirit to SPH [35]. It was not until 2002 that the first application of SPH for the simulation of viscoelastic flows was attempted by Ellero et al [36], where a corotational Jaumann-Maxwell model was used to describe the viscoelastic behavior of the fluid and a particularly simple time-dependent problem of the viscoelastic relaxation in a 2D channel was solved by SPH.…”

Modeling of Metals and Metal Sponges via Embedded Particle Computer Simulation

“…Shear induced breakup of structure is observed. For example, at the highest density a polycrystalline conformation with rotating entities is observed (and finally a bcc dominated structure) whereas for smaller densities a more homogeneous evolution (towards fcc) is visible from the plots [20] the highest density a polycrystalline conformation with rotating entities is observed (and finally a bcc dominated structure) whereas for smaller densities a more homogeneous evolution (towards fcc) is visible from the plots. A structural analysis and structure factors for a sample snapshot at density flow direction figure).…”

“…In the early works [7], F was taken from electron gas computations provided in [18]. We will review a set of particularly simple and generic model potentials [19,20] motivated through semiempirical calculations which are expected to describe the mechanical properties of metals ranging from the nanometer scale (asperites) up to the macroscopic scale (solid friction, metal foams). The model is characterized by a few model parameters such as reference energy, time and length.…”