Dynamic Impact Tests of Tantalum Single Crystals

In this work, Taylor impact experiments are conducted using tantalum single crystals to understand their dynamic behaviors and plastic anisotropy. Tantalum single crystals oriented along [100], [110], [111] and [149] directions are tested at different impact velocities to examine their orientation dependent mechanical behaviors at various strain rates and temperatures. Single crystals showed highly localized deformation and strong plastic anisotropy compared to polycrystalline tantalum. In addition, [100], [110] and [111] single crystals exhibited four, two and three-fold symmetries in their impact surfaces, respectively. A simple crystallographic analysis based on the Schmid law is used to understand the observed symmetries in deformed single crystal projectiles. The first Taylor impact tests using single crystals suggest that the crystallography strongly influences deformation behaviors at high strain rates and temperature regimes.