All-atom molecular-level computational analyses of polyurea/fused-silica interfacial decohesion caused by impinging tensile stress-waves

M. Grujicic (Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA)
R. Yavari (Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA)
J.S. Snipes (Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA)
S. Ramaswami (Department of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA)
R.S. Barsoum (Office of Naval Research, Ships and Engineering Systems Division, Arlington, Virginia, USA)

International Journal of Structural Integrity

ISSN: 1757-9864

Publication date: 11 November 2014

Abstract

Purpose

The purpose of this paper is to address the problems of interaction of tensile stress-waves with polyurea/fused-silica and fused-silica/polyurea interfaces, and the potential for the accompanying interfacial decohesion.

Design/methodology/approach

The problems are investigated using all-atom non-equilibrium molecular-dynamics methods and tools. Before these methods/tools are employed, previously determined material constitutive relations for polyurea and fused-silica are used, within an acoustic-impedance-matching procedure, to predict the outcome of the interactions of stress-waves with the material-interfaces in question. These predictions pertain solely to the stress-wave/interface interaction aspects resulting in the formation of transmitted and reflected stress- or release-waves, but do not contain any information regarding potential interfacial decohesion. Direct molecular-level simulations confirmed some of these predictions, but also provided direct evidence of the nature and the extent of interfacial decohesion. To properly model the initial state of interfacial cohesion and its degradation during stress-wave-loading, reactive forcefield potentials are utilized.

Findings

Direct molecular-level simulations of the polyurea/fused-silica interfacial regions prior to loading revealed local changes in the bonding structure, suggesting the formation of an interphase. This interphase was subsequently found to greatly affect the polyurea/fused-silica decohesion strength.

Originality/value

To the authors’ knowledge, the present work is the first public-domain report of the use of the non-equilibrium molecular dynamics and reactive force-field potentials to study the problem of interfacial decohesion caused by the interaction of tensile waves with material interfaces.

Keywords

Citation

Grujicic, M., Yavari, R., Snipes, J., Ramaswami, S. and Barsoum, R. (2014), "All-atom molecular-level computational analyses of polyurea/fused-silica interfacial decohesion caused by impinging tensile stress-waves", International Journal of Structural Integrity, Vol. 5 No. 4, pp. 339-367. https://doi.org/10.1108/IJSI-01-2014-0001

Download as .RIS

Publisher

:

Emerald Group Publishing Limited

Copyright © 2014, Emerald Group Publishing Limited

Please note you might not have access to this content

You may be able to access this content by login via Shibboleth, Open Athens or with your Emerald account.
If you would like to contact us about accessing this content, click the button and fill out the form.
To rent this content from Deepdyve, please click the button.