Abstract :
A comparative study of the deformation behavior of tantalum and a tantalum 2.5 wt.% tungsten alloy is carried out. High strain-rate experimental data are used to develop phenomenological constitutive relations. The temperature and the strain-rate sensitivity of the flow stresses are compared. It is observed that although the flow stress for the Ta–2.5%W alloy is greater than that of Ta, the corresponding temperature and strain-rate sensitivity is less pronounced. Ta–2.5%W experiences a solid-solution softening, wherein the athermal stress component has increased, while the thermal component has decreased by the alloying.