Atomic-scale simulation of intergranular segregation of H in Al-Mg: implications for H-induced damage

• Published in: Philosophical magazine (Abingdon, England) England), 2003-12, Vol.83 (35), p.3995-4009
• Main Authors: Tanguy, D., Magnin, T.
• Format: Article
• Language: English
• Subjects: Atom and molecule irradiation effects; Condensed matter: structure, mechanical and thermal properties; Defects and impurities in crystals; microstructure; Exact sciences and technology; Grain and twin boundaries; Physical radiation effects, radiation damage; Physics; Point defects (vacancies, interstitials, color centers, etc.) and defect clusters; Structure of solids and liquids; crystallography
• ISSN: 1478-6435; 1478-6443
• DOI: 10.1080/14786430310001613192

The goal of this work is to make a contribution to the understanding of the microscopic mechanisms of H-induced intergranular damage. We develop an embedded-atom method interatomic potential for H in the Al-Mg system with the main aim of reproducing the current understanding of H trapping to vacancies. This model is used to investigate the effect of the Mg-H affinity on the segregation of H on the Σ =5 (310) [001] grain boundary. Monte Carlo simulations in the grand canonical ensemble are used to estimate equilibrium H concentrations at this boundary at T=300 K. A large structure change, associated with the H enrichment of the grain boundary, is reported. The implications on damage to the interface are discussed.