Ab initio study of interaction of helium with edge and screw dislocations in tungsten

Alexander Bakaev, Dmitry Terentyev, Petr Grigorev, Matthias Posselt, Evgeni E. Zhurkin

    Research outputpeer-review


    The interaction of a single He atom with edge and screw dislocations in tungsten has been studied using ab initio calculations. It was revealed that He is strongly attracted to the core of both dislocations with the interaction energy of −1.3 and −3.0 eV for screw and edge dislocations, respectively, which corresponds to the detrapping temperature in thermal desorption spectroscopy experiments of about 500 K and 1050 K, respectively. The lowest energy positions for He around the dislocation cores are identified and the atomic structures are rationalized on the basis of elasticity theory considerations. Both types of dislocations exhibit a higher binding energy for He as compared to the He-He binding (known as self-trapping) and are weaker traps as compared to a single vacancy. It is, thus, concluded that the strong attraction to dislocation lines can contribute to the nucleation of He clusters in the temperature range which already excludes He self-trapping. © 2016 Elsevier B.V.
    Original languageEnglish
    Title of host publicationNuclear Fusion
    Subtitle of host publication13th International Conference on Computer Simulation of Radiation Effects in Solids (COSIRES)
    Number of pages5
    StatePublished - 15 Feb 2017
    Event2016 - COSIRES: Computer Simulation of Radiation Effects in Solids - Loughborough
    Duration: 19 Jun 201624 Jun 2016

    Publication series

    NameNuclear Instruments and Methods in Physics Research Section B


    Conference2016 - COSIRES
    Country/TerritoryUnited Kingdom
    Internet address

    Cite this