Molecular dynamics simulations of shock-induced plasticity in tantalum
Artikel i vetenskaplig tidskrift, 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.

Shocks

Tantalum

Molecular dynamics

Författare

Diego Tramontina

Universidad Nacional de Cuyo

Paul Erhart

Chalmers, Teknisk fysik, Material- och ytteori

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 Universitat 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 9-15

Ämneskategorier

Fysik

Annan fysik

Den kondenserade materiens fysik

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

Styrkeområden

Materialvetenskap

DOI

10.1016/j.hedp.2013.10.007