The ideal tensile strength and deformation behavior of a tungsten single crystal

We employ first-principles total energy method based on the density functional theory with the generalized gradient approximation to investigate the ideal tensile strengths of a bcc tungsten (W) single crystal systemically. The ideal tensile strengths are shown to be 29.1, 49.2 and 37.6 GPa for bcc W in the [0 0 1], [1 1 0] and [1 1 1] directions, respectively. The [0 0 1] direction is shown to be the weakest direction due to the occurrence of structure transition at the lower strain and the [1 1 0] direction is strongest. The results can provide a useful reference for W as a PFM in the nuclear fusion Tokamak. (C) 2009 Elsevier B.V. All rights reserved.