Fracture properties of nanoscale single-crystal silicon plates: Molecular dynamics simulations and finite element method

Developing new techniques for the prediction of materials behaviors in nano-scales has been an attractive and challenging area for many researches. Molecular Dynamics (MD) is the popular method that is usually used to simulate the behavior of nano-scale material. Considering high computational costs of MD, however, has made this technique inapplicable as well as inflexible in various situations. To overcome these difficulties, alternative procedures are thought. Considering its capabilities, Finite Element Analysis (FEA) seems to be the most appropriate substitute for MD simulations in most cases. But since the material properties in nano, micro, and macro scales are different, therefore to use FEA methods in nano-scale modeling one must use material properties appropriate to that scale. To this end, a previously developed Hybrid Molecular Dynamics-Finite Element (HMDFE) approach was used to investigate the nanoindentation behavior of single crystal silicon with Berkovich indenter. In this study, a FEA model was developed based on the material properties extracted from molecular dynamics simulation of uniaxial tension test on single crystal Silicon. Eventually, by comparison of FEA results with experimental data, the validity of this new technique for the prediction of nanoindentation behavior of Silicon was concluded.

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Potential Analysis in Nanoturning of Single Crystal Silicon Using Molecular Dynamics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.3236 ◽

2011 ◽

Vol 239-242 ◽

pp. 3236-3239 ◽

Cited By ~ 2

Author(s):

Ying Chun Liang ◽

Zhi Guo Wang ◽

Ming Jun Chen ◽

Jia Xuan Chen ◽

Zhen Tong

Keyword(s):

Molecular Dynamics ◽

Single Crystal ◽

Diamond Tool ◽

Single Crystal Silicon ◽

Crystal Silicon ◽

Potential Analysis ◽

Ductile Mode ◽

Tool Surface ◽

Dynamics Simulations ◽

Nanoscale Cutting

Molecular dynamics simulations of the single crystal silicon nanoscale cutting with a diamond tool in ductile mode are carried out to investigate the adhesion phenomenon. After relaxation the silicon atoms on the surface reconstruct to make the potential decrease. The silicon atoms close to the diamond tool have the lowest potential (<-5.5 eV) and form a stable structure with surface atoms on the tool surface.

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Stochastic Finite Element Method (FEM) and Design of Experiments for Pressure Vessel and Piping (PVP) Decision Making

Volume 6: Materials and Fabrication ◽

10.1115/pvp2006-icpvt-11-93927 ◽

2006 ◽

Cited By ~ 1

Author(s):

Jeffrey T. Fong ◽

James J. Filliben ◽

Roland deWit ◽

Barry Bernstein

Keyword(s):

Finite Element Method ◽

Decision Making ◽

Finite Element ◽

Design Of Experiments ◽

Single Crystal Silicon ◽

Quantitative Measure ◽

Crystal Silicon ◽

Stochastic Fem ◽

Anisotropic Elastic ◽

Element Method

Using an example from a recent study of the finite element method (FEM) solutions of the natural frequencies of single-crystal silicon cantilevers in atomic force microscopy (AFM), we present the results of an analysis using two powerful tools of engineering statistics, namely, (a) stochastic FEM, and (b) design of experiments. The analysis of the FEM results using ABAQUS, ANSYS, and LS-DYNA anisotropic elastic element types yields conclusions that engineers can use to justify decisions with quantitative measure of uncertainties. For PVP engineers, we show with an example that this methodology is equally applicable to their decision making process and the appropriate risk assessment.

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Torsion/Simple Shear of Single Crystal Copper

Journal of Engineering Materials and Technology ◽

10.1115/1.1480407 ◽

2002 ◽

Vol 124 (3) ◽

pp. 322-328 ◽

Cited By ~ 18

Author(s):

M. F. Horstemeyer ◽

J. Lim ◽

W. Y. Lu ◽

D. A. Mosher ◽

M. I. Baskes ◽

...

Keyword(s):

Molecular Dynamics ◽

Finite Element ◽

Single Crystal ◽

Molecular Dynamics Simulations ◽

Simple Shear ◽

Wave Amplitude ◽

Finite Element Simulations ◽

Deformation Wave ◽

Single Crystal Copper ◽

Dynamics Simulations

We analyze simple shear and torsion of single crystal copper by employing experiments, molecular dynamics simulations, and finite element simulations in order to focus on the kinematic responses and the apparent yield strengths at different length scales of the specimens. In order to compare torsion with simple shear, the specimens were designed to be of similar size. To accomplish this, the ratio of the cylinder circumference to the axial gage length in torsion equaled the ratio of the length to height of the simple shear specimens (0.43). With the [110] crystallographic direction parallel to the rotational axis of the specimen, we observed a deformation wave of material that oscillated around the specimen in torsion and through the length of the specimen in simple shear. In torsion, the ratio of the wave amplitude divided by cylinder circumference ranged from 0.02–0.07 for the three different methods of analysis: experiments, molecular dynamics simulations, and finite element simulations. In simple shear, the ratio of the deformation wave amplitude divided by the specimen length and the corresponding values predicted by the molecular dynamics and finite element simulations (simple shear experiments were not performed) ranged from 0.23–0.26. Although each different analysis method gave similar results for each type boundary condition, the simple shear case gave approximately five times more amplitude than torsion. We attributed this observation to the plastic spin behaving differently as the simple shear case constrained the dislocation activity to planar double slip, but the torsion specimen experienced quadruple slip. The finite element simulations showed a clear relation with the plastic spin and the oscillation of the material wave. As for the yield stress in simple shear, a size scale dependence was found regarding two different size atomistic simulations for copper (332 atoms and 23628 atoms). We extrapolated the atomistic yield stresses to the order of a centimeter, and these comparisons were close to experimental data in the literature and the present study.

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Nanoindentation of single-crystal and polycrystalline yttria-stabilized zirconia: A comparative study by experiments and molecular dynamics simulations

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.160336 ◽

2021 ◽

pp. 160336

Author(s):

Jianli Zhou ◽

Zhenjun Jiao ◽

Jin Zhang ◽

Zheng Zhong

Keyword(s):

Molecular Dynamics ◽

Comparative Study ◽

Single Crystal ◽

Molecular Dynamics Simulations ◽

Yttria Stabilized Zirconia ◽

Stabilized Zirconia ◽

Dynamics Simulations

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THE ATOMIC FINITE ELEMENT METHOD AS A BRIDGE BETWEEN MOLECULAR DYNAMICS AND CONTINUUM MECHANICS

Journal of Multiscale Modelling ◽

10.1142/s1756973711000339 ◽

2011 ◽

Vol 03 (01n02) ◽

pp. 39-47 ◽

Cited By ~ 6

Author(s):

R. NEUGEBAUER ◽

R. WERTHEIM ◽

U. SEMMLER

Keyword(s):

Finite Element Method ◽

Molecular Dynamics ◽

Finite Element ◽

High Performance ◽

Cutting Tools ◽

Deposition Process ◽

Dislocation Behavior ◽

Crystal Plasticity Fem ◽

The Continuum ◽

Element Method

On cutting tools for high performance cutting (HPC) processes or for hard-to-cut materials, there is an increased importance in so-called superlattice coatings with hundreds of layers each of which is only a few nanometers in thickness. Homogeneity or average material properties based on the properties of single layers are not valid in these dimensions any more. Consequently, continuum mechanical material models cannot be used for modeling the behavior of nanolayers. Therefore, the interaction potentials between the single atoms should be considered. A new, so-called atomic finite element method (AFEM) is presented. In the AFEM the interatomic bonds are modeled as nonlinear spring elements. The AFEM is the connection between the molecular dynamics (MD) method and the crystal plasticity FEM (CPFEM). The MD simulates the atomic deposition process. The CPFEM considers the behavior of anisotropic crystals using the continuum mechanical FEM. On one side, the atomic structure data simulated by MD defines the interface to AFEM. On the other side, the boundary conditions (displacements and tractions) of the AFEM model are interpolated from the CPFEM simulations. In AFEM, the lattice deformation, the crack and dislocation behavior can be simulated and calculated at the nanometer scale.

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