Interaction of hydrogen and helium with nanometric dislocation loops in tungsten assessed by atomistic calculations

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Beam interactions with materials and atoms, 2017-02, Vol.393, p.164-168
• Main Authors: Grigorev, Petr, Bakaev, Alexander, Terentyev, Dmitry, Van Oost, Guido, Noterdaeme, Jean-Marie, Zhurkin, Evgeny E.
• Format: Article
• Language: English
• Subjects: Dislocation loops; Helium; Hydrogen retention; Molecular Dynamics; Tungsten
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2016.10.036

The interaction of H and He interstitial atoms with ½〈111〉 and 〈100〉 loops in tungsten (W) was studied by means of Molecular Static and Molecular Dynamics simulations. A recently developed interatomic potential was benchmarked using data for dislocation loops obtained earlier with two other W potentials available in literature. Molecular Static calculations demonstrated that ½〈111〉 loops feature a wide spectrum of the binding energy with a maximum value of 1.1eV for H and 1.93eV for He as compared to 0.89eV and 1.56eV for a straight ½〈111〉{110} edge dislocation. For 〈100〉 loops, the values of the binding energy were found to be 1.63eV and 2.87eV for H and He, respectively. These results help to better understand the role played by dislocation loops in H/He retention in tungsten. Based on the obtained results, a contribution of the considered dislocation loops to the trapping and retention under plasma exposure is discussed.