Molecular dynamics simulations of shock-induced plasticity in tantalum
Journal article, 2014
We present Non-Equilibrium Molecular Dynamics (NEMD) simulations of shock wave compression along the [001] direction in monocrystalline Tantalum, including pre-existing defects which act as dislocation sources. We use a new Embedded Atom Model (EAM) potential and study the nucleation and evolution of dislocations as a function of shock pressure and loading rise time. We find that the flow stress and dislocation density behind the shock front depend on strain rate. We find excellent agreement with recent experimental results on strength and recovered microstructure, which goes from dislocations to a mixture of dislocations and twins, to twinning dominated response, as the shock pressure increases.
Tantalum
Shocks
Molecular dynamics
Author
Diego Tramontina
Universidad Nacional de Cuyo
Paul Erhart
Chalmers, Applied Physics, Materials and Surface Theory
Timothy Germann
Los Alamos National Laboratory
James Hawreliak
Lawrence Livermore National Laboratory
Andrew Higginbotham
University of Oxford
Nigel Park
Atomic Weapons Establishment
Raman Ravelo
Los Alamos National Laboratory
University of Texas at El Paso
Alexander Stukowski
Technische Universität Darmstadt
Mathew Suggit
University of Oxford
Yizhe Tang
Johns Hopkins University
Justin Wark
University of Oxford
Eduardo Bringa
Universidad Nacional de Cuyo
Consejo Nacional de Investigaciones Cientificas y Tecnicas
High Energy Density Physics
1574-1818 (ISSN)
Vol. 10 3 9-15Subject Categories
Physical Sciences
Other Physics Topics
Condensed Matter Physics
Infrastructure
C3SE (Chalmers Centre for Computational Science and Engineering)
Areas of Advance
Materials Science
DOI
10.1016/j.hedp.2013.10.007