skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A Comparison of 3D Finite Element Simulations for Berkovich and Conical Indentation of Fused Silica

Abstract

Much of our understanding of elastic-plastic contact mechanics as it relates to the interpretation of nanoindentation data comes from two-dimensional, axisymmetric finite element simulations of conical indentation. In many instances, conical results adequately describe real experimental results; however, there are instances where conical simulations fail to capture important behavior. Three-dimensional finite element simulations of Berkovich triangular pyramidal indentation of fused silica are compared to similar simulations with a 70.3{sup o} cone. It is shown that a potentially significant difference between the two indenters exists for the contact areas and contact stiffnesses. Implications for the interpretation of nanoindentation data are discussed.

Authors:
 [1];  [2];  [1]
+ Show Author Affiliations
  1. ORNL
  2. MTS Nanoinstruments Innovation Center, Oak Ridge
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shared Research Equipment Collaborative Research Center
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
935723
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Surface Science and Engineering; Journal Volume: 1; Journal Issue: 2-3
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; SILICA; THREE-DIMENSIONAL CALCULATIONS; FINITE ELEMENT METHOD; ELASTICITY; PLASTICITY; CONICAL CONFIGURATION

Citation Formats

Shim, Sang Hoon, Oliver, Warren C., and Pharr, George Mathews. A Comparison of 3D Finite Element Simulations for Berkovich and Conical Indentation of Fused Silica. United States: N. p., 2007. Web. doi:10.1504/IJSURFSE.2007.015028.
Copy to clipboard
Shim, Sang Hoon, Oliver, Warren C., & Pharr, George Mathews. A Comparison of 3D Finite Element Simulations for Berkovich and Conical Indentation of Fused Silica. United States. doi:10.1504/IJSURFSE.2007.015028.
Copy to clipboard
Shim, Sang Hoon, Oliver, Warren C., and Pharr, George Mathews. Mon . "A Comparison of 3D Finite Element Simulations for Berkovich and Conical Indentation of Fused Silica". United States. doi:10.1504/IJSURFSE.2007.015028.
Copy to clipboard
@article{osti_935723,
title = {A Comparison of 3D Finite Element Simulations for Berkovich and Conical Indentation of Fused Silica},
author = {Shim, Sang Hoon and Oliver, Warren C. and Pharr, George Mathews},
abstractNote = {Much of our understanding of elastic-plastic contact mechanics as it relates to the interpretation of nanoindentation data comes from two-dimensional, axisymmetric finite element simulations of conical indentation. In many instances, conical results adequately describe real experimental results; however, there are instances where conical simulations fail to capture important behavior. Three-dimensional finite element simulations of Berkovich triangular pyramidal indentation of fused silica are compared to similar simulations with a 70.3{sup o} cone. It is shown that a potentially significant difference between the two indenters exists for the contact areas and contact stiffnesses. Implications for the interpretation of nanoindentation data are discussed.},
doi = {10.1504/IJSURFSE.2007.015028},
journal = {International Journal of Surface Science and Engineering},
number = 2-3,
volume = 1,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
Copy to clipboard
Journal Article:
DOI:  10.1504/IJSURFSE.2007.015028
Other availability
Find in Google Scholar Find in Google Scholar
Search WorldCat Search WorldCat to find libraries that may hold this journal
Save / Share:
Export Metadata
Save to My Library
You must Sign In or Create an Account in order to save documents to your library.

  • ; ; ; ... - AIP Conference Proceedings
    SLAC's Advanced Computations Department (ACD) has developed the first parallel Finite Element 3D Particle-In-Cell (PIC) code, Pic3P, for simulations of RF guns and other spacecharge dominated beam-cavity interactions. Pic3P solves the complete set of Maxwell-Lorentz equations and thus includes space charge, retardation and wakefield effects from first principles. Pic3P uses higher-order Finite Element methods on unstructured conformal meshes. A novel scheme for causal adaptive refinement and dynamic load balancing enable unprecedented simulation accuracy, aiding the design and operation of the next generation of accelerator facilities. Application to the Linac Coherent Light Source (LCLS) RF gun is presented.

  • ; ; ; ... - Medical Physics
    Purpose: To design a new compact S-band linac waveguide capable of producing a 10 MV x-ray beam, while maintaining the length (27.5 cm) of current 6 MV waveguides. This will allow higher x-ray energies to be used in our linac-MRI systems with the same footprint. Methods: Finite element software COMSOL Multiphysics was used to design an accelerator cavity matching one published in an experiment breakdown study, to ensure that our modeled cavities do not exceed the threshold electric fields published. This cavity was used as the basis for designing an accelerator waveguide, where each cavity of the full waveguide wasmore » tuned to resonate at 2.997 GHz by adjusting the cavity diameter. The RF field solution within the waveguide was calculated, and together with an electron-gun phase space generated using Opera3D/SCALA, were input into electron tracking software PARMELA to compute the electron phase space striking the x-ray target. This target phase space was then used in BEAM Monte Carlo simulations to generate percent depth doses curves for this new linac, which were then used to re-optimize the waveguide geometry. Results: The shunt impedance, Q-factor, and peak-to-mean electric field ratio were matched to those published for the breakdown study to within 0.1% error. After tuning the full waveguide, the peak surface fields are calculated to be 207 MV/m, 13% below the breakdown threshold, and a d-max depth of 2.42 cm, a D10/20 value of 1.59, compared to 2.45 cm and 1.59, respectively, for the simulated Varian 10 MV linac and brehmsstrahlung production efficiency 20% lower than a simulated Varian 10 MV linac. Conclusion: This work demonstrates the design of a functional 27.5 cm waveguide producing 10 MV photons with characteristics similar to a Varian 10 MV linac.« less

  • ; ; ; ... - Journal of Experimental and Theoretical Physics
    The formation of conical emission of supercontinuum during filamentation of femtosecond laser pulses with central wavelengths in a wide range is studied experimentally, numerically, and analytically. The frequency-angular intensity distribution of the spectral components of conical emission is determined by the interference of supercontinuum emission in a filament of a femtosecond laser pulse. The interference of supercontinuum emission has a general character, exists at different regimes of group velocity dispersion, gives rise to the fine spectral structure after the pulse splitting into subpulses and the formation of a distributed supercontinuum source in an extended filament, and causes the decomposition ofmore » the continuous spectrum of conical emission into many high-contrast maxima after pulse refocusing in the filament. In spectroscopic studies with a tunable femtosecond radiation source based on a TOPAS parametric amplifier, we used an original scheme with a wedge fused silica sample. Numerical simulations have been performed using a system of equations of nonlinear-optical interaction of laser radiation under conditions of diffraction, wave nonstationarity, and material dispersion in fused silica. The analytic study is based on the interference model of formation of conical emission by supercontinuum sources moving in a filament.« less

  • ; ; ; ... - Fatigue and Fracture of Engineering Materials and Structures
    In an effort to reproduce computationally the observed evolution of microstructurally small fatigue cracks (MSFCs), a method is presented for generating conformal, finite-element (FE), volume meshes from 3D measurements of MSFC propagation. The resulting volume meshes contain traction-free surfaces that conform to incrementally measured 3D crack shapes. Grain morphologies measured using near-field high-energy X-ray diffraction microscopy are also represented within the FE volume meshes. Proof-of-concept simulations are performed to demonstrate the utility of the mesh-generation method. The proof-of-concept simulations employ a crystal-plasticity constitutive model and are performed using the conformal FE meshes corresponding to successive crack-growth increments. Although the simulationsmore » for each crack increment are currently independent of one another, they need not be, and transfer of material-state information among successive crack-increment meshes is discussed. The mesh-generation method was developed using post-mortem measurements, yet it is general enough that it can be applied to in-situ measurements of 3D MSFC propagation.« less
    Cited by 2

  • ; ; - AIP Conference Proceedings
    This paper presents different finite element simulations of thixoforging realised on Forge2(c) software. Compression and axial extrusion tests are particularly studied. The constitutive equation used for these simulations is based on a micro-macro approach accounting for the semi-solid microstructural evolution. The constitutive equation parameters are identified thanks to successive comparisons of the simulated load-displacement responses with experimental ones for compression tests on steel semi-solid at different temperatures. The relevance of the modelling is then analysed through extrusion tests. It is shown that the constitutive equation developed by the authors provides simulated results closer to the experimental ones than the classicalmore » Norton-Hoff law. It demonstrates the capacity of prediction of such a modelling. Moreover, these simulations give a lot of information concerning the role of parameters such as solid fraction, initial solid skeleton degree of agglomeration, thermal exchanges, or strain rate during thixoforging of high melting point materials.« less