Cohesion enhancing effect of magnesium in aluminum grain boundary: A first-principles determination
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States)
- Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208 (United States)
The effect of magnesium on grain boundary cohesion in aluminum was investigated by means of first-principles calculations using the Rice-Wang model [Rice and Wang, Mater. Sci. Eng. A 107, 23 (1989)]. It is demonstrated that magnesium is a cohesion enhancer with a potency of -0.11 eV/atom. It is further determined through electronic structure and bonding character analysis that the cohesion enhancing property of magnesium is due to a charge transfer mechanism which is unusually strong and overcomes the negative result of the size effect mechanism. Consistent with experimental results, this work clarifies the controversy and establishes that Mg segregation does not contribute to stress corrosion cracking in Al alloys.
- OSTI ID:
- 22025582
- Journal Information:
- Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 23 Vol. 100; ISSN APPLAB; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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