Orientation-dependent response of nanovoids in Tantalum*

Defective BCC Tantalum monocrystals are expected to display a particularly rich behavior when stressed along different directions. Using molecular dynamics simulations, we model Ta monocrystals containing a single spherical void of different sizes, under uniaxial compression, for two different empirical potentials. Differences on the yield point, dislocation generation and plastic heating are observed depending on the void size and stress direction, as distinct slip systems are activated, resulting in a variety of dislocation structures and mobilities. We calculate plastic heating and dislocation densities, and compare results for different interatomic potentials.