Molecular-level Analysis of Shock-wave Physics and Derivation of the Hugoniot Relations for Soda-lime Glass
Abstract
Non-equilibrium and equilibrium molecular dynamics simulations are employed to study the mechanical response of soda-lime glass (a material commonly used in transparent armor applications) when subjected to the loading conditions associated with the generation and propagation of planar shock waves. Particular attention is given to the identification and characterization of various (inelastic-deformation and energy-dissipation) molecular-level phenomena and processes taking place at the shock front. The results obtained revealed that the shock loading causes a 2 4% (shock strength-dependent) density increase. In addition, an increase in the average coordination number of the silicon atoms is observed along with the creation of smaller Si O rings. These processes are associated with significant energy absorption and dissipation and are believed to control the blast/ballistic impact mitigation potential of soda-lime glass. This study was also aimed at the determination (via purely computational means) of the shock Hugoniot (i.e., a set of axial stress vs. density/specific-volume vs. internal energy vs. particle velocity vs. temperature) material states obtained in soda-lime glass after the passage of a shock wave of a given strength and on the comparison of the computed results with their experimental counterparts. The availability of a shock Hugoniot is critical for construction of a high deformation-rate, large-strain, high pressure material model which can be used within a continuum-level computational analysis to capture the response of a soda-lime glass-based laminated transparent armor structure (e.g., a military vehicle windshield, door window, etc.) to blast/ ballistic impact loading.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 17, 2011
- Accession Number
- ADA585322
Entities
People
- B. Pandurangan
- Bryan A. Cheeseman
- George A. Gazonas
- M. Grujičić
- Pranav Patel
- W. C. Bell
Organizations
- United States Army Research Laboratory