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

Research output: Contribution to report/book/conference proceedingsIn-proceedings paper

Authors

Institutes & Expert groups

  • HZDR - Helmholtz,Zentrum Dresden, Rossendorf
  • PbPU - Peter the Great St.Petersburg Polytechnic University - Russia

Documents & links

Abstract

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.

Details

Original languageEnglish
Title of host publicationNuclear Fusion
Subtitle of host publication13th International Conference on Computer Simulation of Radiation Effects in Solids (COSIRES)
Pages150-154
Number of pages5
Volume393
Edition2017
DOIs
Publication statusPublished - 15 Feb 2017
Event2016 - COSIRES: Computer Simulation of Radiation Effects in Solids - Loughborough, United Kingdom
Duration: 19 Jun 201624 Jun 2016
http://www.cosires2016.co.uk/

Publication series

NameNuclear Instruments and Methods in Physics Research Section B
PublisherElsevier

Conference

Conference2016 - COSIRES
CountryUnited Kingdom
CityLoughborough
Period2016-06-192016-06-24
Internet address

Keywords

  • Ab initio, Ab initio calculations, Dislocation lines, Edge and screw dislocations, Elasticity theory, Interaction energies, Single vacancies, Temperature range

ID: 6775827