The deformation of polycrystalline tungsten at 200°C

Abstract

The strain rate sensitivity of the stress at the apparent proportional limit, [sgrave]_A, and the variation of dislocation density with strain have been investigated for polycrystalline tungsten deformed at 200°c. The results are consistent with Hahn's (1962) theory of yielding and the dislocation velocities at [sgrave]_A evaluate to ∼ 10⁻⁴ and ∼ 10⁻² cm sec⁻¹ at strain rates of 1 and 50% min⁻¹, respectively.