The Effect of Vanadium Doping on Carbon Behavior in Tungsten: A First-Principle Study

Using density functional theory based on first-principles and selecting W15V1${{\rm{W}}_{15}}{{\rm{V}}_1}$ structure to replace WV${\rm{WV}}$ alloy, the electronic properties and mechanical properties of W15V1${{\rm{W}}_{15}}{{\rm{V}}_1}$ and W15V1C${{\rm{W}}_{15}}{{\rm{V}}_1}{\rm{C}}$ are investigated in this paper. These properties are compared to investigate the effect of radiation of carbon (C) impurity on W15V1${{\rm{W}}_{15}}{{\rm{V}}_1}$ lattice when WV${\rm{WV}}$ alloy is applied as plasma facing materials in a nuclear fusion device. It is found that carbon impurity can greatly improve the ductility of tungsten (W) metal and tungsten vanadium (WV) alloy in the W15V1${{\rm{W}}_{15}}{{\rm{V}}_1}$ lattice. For further research, solution energy of one C atom at different positions in W15V1${{\rm{W}}_{15}}{{\rm{V}}_1}$ lattice is also calculated in this paper. It is found that in the W15V1${{\rm{W}}_{15}}{{\rm{V}}_1}$ lattice, the C atom is more energetically favorable sitting at the octahedral interstitial site nearest to V atom, with solution energy of 1.25 eV.