A first-principles investigation of interstitial defects in dilute tungsten alloys
Journal article, 2015
The thermodynamic properties of intrinsic and extrinsic (Ti, V, Zr, Nb, Hf, Ta, Re) defects in tungsten have been investigated using density functional theory calculations. The formation energies of substitutional defects are discussed with respect to their thermodynamic solubility limits. Several different interstitial configurations have been identified as local minima on the potential energy surface. In addition to dumbbell configurations with orientations along < 111 > and < 110 >, a lower symmetry configuration is described, which is referred to as a bridge interstitial. This interstitial type is found to be the lowest energy configuration for mixed-interstitials containing Ti, V, and Re, and can be up to 0.2 eV lower in energy than the other configurations. According to the calculations Ti, V and Re also trap self-interstitial atoms, which can be produced in substantial numbers during ion irradiation, affecting the mobility of the latter. (C) 2015 Elsevier B.V. All rights reserved.
1972
Defects
Interstitials
Radiation-induced segregation
p315
metals
displacement field
Nuclear Science & Technology
total-energy calculations
derich.ph
point-defects
v255
Processing
Mining & Mineral
crystals
augmented-wave method
calculations
Trapping
molecular-dynamics simulations
Tungsten alloys
transition
Materials Science
zeitschrift fur physik
ab-initio
basis-set
Ion irradiation
Author
Leili Gharaee
Chalmers, Applied Physics, Materials and Surface Theory
Paul Erhart
Chalmers, Applied Physics, Materials and Surface Theory
Journal of Nuclear Materials
0022-3115 (ISSN)
Vol. 467 448-456Subject Categories
Subatomic Physics
Metallurgy and Metallic Materials
DOI
10.1016/j.jnucmat.2015.09.003