Hostname: page-component-7479d7b7d-767nl Total loading time: 0 Render date: 2024-07-11T21:25:10.276Z Has data issue: false hasContentIssue false
  • English
  • Français

Phase Stability, Point Defects and Site Preference of Feal and Nial with Ternary Additions

Published online by Cambridge University Press:  22 February 2011

C.L. Fu  and
J. Zou
C.L. Fu
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, P. O. Box 2008, Oak Ridge, TN 37831-6114
J. Zou
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, P. O. Box 2008, Oak Ridge, TN 37831-6114
Get access

Abstract

First-principles calculations have been used to investigate the defect properties and the site preference of FeAl and NiAl with ternary additions. It is found that a “triple-defect” structure model becomes invalid in describing the defect structure of FeAl (which is weakly ordered). The calculated mono-vacancy concentration on the Fe sites is lower than available experimental values by an order of magnitude, which may suggest the formation of defect complexes or the need of sufficiently long annealing time to anneal out quenched-in vacancies. For the site preference of ternary additions in FeAl, Cr and Ti are found to occupy Al sublattices, whereas Ni has a distinct preference for the Fe sites. The substitutional behavior of ternary elements in FeAl is consistent with the trend in the calculated heat-of-formation. For Fe addition in Al-rich NiAl, Fe atoms occupy Ni sublattices exclusively. The site preference of Fe addition in Ni-rich NiAl is dependent on alloy composition and temperature. At low temperatures, Fe atoms are found to preferentially occupy Al sublattices in Ni-rich alloys.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 364: Symposium L – High-Temperature Ordered Intermetallic Alloys–VI , 1994 , 91
Copyright
Copyright © Materials Research Society 1995

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. Schneibel, J. H., George, E. P., Specht, E. D., and Horton, J. A., (these proceedings).Google Scholar
2. Darolia, R., Lahrman, D., and Field, R., Scripta Metall. Mater. 26, 1007 (1992).Google Scholar
3. Fu, C. L., Ye, Y. Y., Yoo, M. H., and Ho, K. M., Phys. Rev. B48, 6712 (1993).Google Scholar
4. Zou, J. and Fu, C. L., Phys. Rev. B (Jan. 1995).Google Scholar
5. Chang, Y. A., Pike, L. M., Liu, C. T. et al., Intermetallics 1, 107 (1993).Google Scholar
6. Ho, K. and Dodd, R. A., Scripta Matall. 12, 1055 (1978).Google Scholar
7. Khosla, S. et al., in Alloy Modeling and Design, Stocks, G. M. and Turchi, P. E. A., eds., TMS publication, p. 257 (1994).Google Scholar
8. Li, D., Li, P., Sun, D., and Lin, D., in High-Temperature Ordered Intermetallics V, Baker, I. et al., eds., Materials Research Society, vol.288, p. 281 (1993).Google Scholar
9. Kong, C. H. and Munroe, P. R., Scripta Metall. Meter. 30, 1079 (1994).Google Scholar
10. Anderson, I. M., Duncan, A. J., and Bentley, J., (these proceedings).Google Scholar
11. Chartier, P. et al., J. Appl. Phys. 75, 3842 (1994)Google Scholar