Shock compression of Ta single crystals with dislocation sources

ORAL

Abstract

We present non-equilibrium molecular dynamics (NEMD) simulations of shock wave compression of line Tantalum single crystals including pre-existing defects, which act as dislocation sources. We use the new embedded atom model (EAM) potential presented by Ravelo \textit{et al.} [Ravelo \textit{et al.}, SCCM2011 paper], developed for shock-wave simulations. We study the nucleation and evolution of dislocations and twins as a function of shock pressure and loading ramp time. We find a large dependence of the HEL (Hugoniot Elastic Limit) on strain rate. We compare the resulting dislocation densities and dislocation structures to existing experimental results on recovered samples.

*This research is funded by the ANPCyT project PICT2008-1325 and 06/M035 from SecTyP-U.N. Cuyo.

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Authors

  • Diego Tramontina

    • Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza, M5502JMA Argentina

  • Ramon Ravelo

    • University of Texas at El Paso
    • University of Texas, El Paso, TX
    • Physics Department and Materials Research Institute, University of Texas, El Paso, TX 79968

  • Eduardo Bringa

    • Instituto de Ciencias Basicas \& CONICET, UNCuyo, Mendoza 5500, Argentina
    • CONICET and Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza, Argentina
    • Universidad Nacional de Cuyo, Argentina
    • ICB-UNCUYO \& CONICET, Mendoza 5500, Argentina
    • CONICET and Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza, 5500 Argentina
    • Consejo Nacional de Investigaciones Cientificas y Tecnicas, CABA, C1033AAJ Argentina
    • Consejo Nacional de Investigaciones Cientificas y Tecnicas. CABA. C1033AAJ Argentina