Theoretical study on hydrogen solubility and diffusivity in the γ-TiAl L10 structure

Abstract : The present work is a discussion on hydrogen solubility and diffusivity in the TiAl-L10 system using first-principles calculations. First, ground-state properties of the TiAl-L10 system are presented and discussed using elastic, phonon and thermal properties. They are compared with literature results. After having analyzed the geometry of L10 using the space-group theory, ten potential interstitial sites for hydrogen insertion were identified (among which the various octahedral and tetrahedral sites). After relaxation, only three configurations remained stable, but one site was significantly more stable than the others. The interactions between hydrogen and metal atoms are then described and analyzed by computing different quantities such as phonon properties, charge transfers, formation volumes and elastic dipoles. Diffusion mechanisms were then studied by analyzing the possible displacements at the atomic scale, and the diffusion coefficient of H atoms in TiAl was finally computed. Results how that H diffusion is strongly anisotropic.
Document type :
Journal articles
Complete list of metadatas

Cited literature [50 references]  Display  Hide  Download
Contributor : Open Archive Toulouse Archive Ouverte (oatao) <>
Submitted on : Monday, May 20, 2019 - 4:31:52 PM
Last modification on : Friday, June 14, 2019 - 6:31:29 PM


 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : 2019-10-10

Please log in to resquest access to the document




Damien Connétable. Theoretical study on hydrogen solubility and diffusivity in the γ-TiAl L10 structure. International Journal of Hydrogen Energy, Elsevier, 2019, 44 (23), pp.12215-12227. ⟨10.1016/j.ijhydene.2019.03.110⟩. ⟨hal-02134645⟩



Record views