17 Interplay of dislocation slip and deformation twinning in tantalum at high strain rates

摘要

Deformation twinning was introduced in Ta through dynamic compression shear and uniaxial compression at high strain rates up to ~10~4 s~(-1) at low temperatures. Under dominant shear, the specimens showed continuous strain softening at high rates, and the deformation twins showed anomalous and highly irregular morphologies. Under compression, deformation twins appeared as typical straight and thin plates accompanied by considerable strain hardening in mechanical response. The results are correlated with the interplay of slip and deformation twinning unique for body-centered cubic metals.