Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-09T13:20:14.847Z Has data issue: false hasContentIssue false

Effect of Boron and Hydrogen on the Electronic Structure of Ni3Al

Published online by Cambridge University Press:  21 February 2011

N. Kioussis
Affiliation:
California State University Northridge, Department of Physics, Northridge, CA 91330
H. Watanabe
Affiliation:
California State University Northridge, Department of Physics, Northridge, CA 91330
R.G. Hemker
Affiliation:
California State University Northridge, Department of Physics, Northridge, CA 91330
W. Gourdin
Affiliation:
Lawrence Livermore National Laboratory, Department of Chemistry and Materials Science, Livermore, CA 94550
A. Gonis
Affiliation:
Lawrence Livermore National Laboratory, Department of Chemistry and Materials Science, Livermore, CA 94550
P.E. Johnson
Affiliation:
Lawrence Livermore National Laboratory, Department of Chemistry and Materials Science, Livermore, CA 94550
Get access

Abstract

Using first-principles electronic structure calculations based on the Linear-Muffin-Tin Orbital (LMTO) method, we have investigated the effects of interstitial boron and hydrogen on the electronic structure of the L12 ordered intermetallic Ni3A1. When it occupies an octahedral interstitial site entirely coordinated by six Ni atoms, we find that boron enhances the charge distribution found in the strongly-bound “pure” Ni3AI crystal: Charge is depleted at Ni and Al sites and enhanced in interstitial region. Substitution of Al atoms for two of the Ni atoms coordinating the boron, however, reduces the interstitial charge density between certain atomic planes. In contrast to boron, hydrogen appears to deplete the interstitial charge, even when fully coordinated by Ni atoms. We suggest that these results are broadly consistent with the notion of boron as a cohesion enhancer and hydrogen as an embrittler.

Type
Research Article
Copyright
Copyright © Materials Research Society 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Liu, C.T., in Alloy Phase Stability, edited by Gonis, A. and Stocks, G.M. (Kluwer Publications, 1989), pp.721.CrossRefGoogle Scholar
2. Liu, C.T., White, C.L., and Horton, J. A., Acta Metall. 33, 213 (1985).Google Scholar
3. Takasugi, T., Masahashi, N., and Izumi, O., Acta. Metall. 35, 381 (1987).Google Scholar
4. Li, H. and Chaki, T.K., Acta Metall. et Mater. 41, 1979 (1993).CrossRefGoogle Scholar
5. George, E.P., Liu, C.T., and Pope, D.P., Scripta Metall. et Mater. 27, 365 (1992).CrossRefGoogle Scholar
6. Lee, K.H. and White, C.L., Scripta Metall. et Mater. 29, 547 (1993).CrossRefGoogle Scholar
7. Ashby, M.F., Spaepen, F. and Williams, S., Acta Metall. 26, 1647 (1978).Google Scholar
8. Kioussis, N., Cooper, B.R., and Wills, J.M., Phys. Rev. B44, 10003 (1991).CrossRefGoogle Scholar
9. Andersen, O.K., Phys. Rev. B12, 3060 (1975); H.L Skriver, The LMTO Method, (Springer, Berlin, 1984).Google Scholar
10. Hedin, L. and Lundqvist, B.I., J. Phys. C 4, 2064 (1971).CrossRefGoogle Scholar
11. Koelling, D.D. and Harmon, B.N., J. Phys. C10, 3107 (1977).Google Scholar