Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-02T21:01:58.407Z Has data issue: false hasContentIssue false

Direct Molecular Dynamics Simulations of Diffusion Mechanisms in NiAl

Published online by Cambridge University Press:  21 March 2011

D. Farkas
Affiliation:
Dept. of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
B. Soulé de Bas
Affiliation:
Dept. of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
Get access

Abstract

Molecular dynamics simulations of the diffusion process in ordered B2 NiAl at high temperature were performed using an embedded atom interatomic potential. Diffusion occurs through a variety of cyclic mechanisms that accomplish the motion of the vacancy through nearest neighbor jumps restoring order to the alloy at the end of the cycle. The traditionally postulated 6-jump cycle is only one of the various cycles observed and some of these are quite complex. A detailed sequential analysis of the observed 6-jump cycles was performed and the results are analyzed in terms of the activation energies for individual jumps calculated using molecular statics simulations.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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

REFERENCES

1. Donaldson, A. T. and Rawlings, R. D., Acta Metall. 24, 285 (1976)Google Scholar
2. Mishin, Y. and Farkas, D., Phil. Mag. A. 75, 1 (1997)Google Scholar
3. Elcock, E. W. and McCombie, C.W., Phys. Rev. 109, 6 (1958)Google Scholar
4. Wynblatt, P., Acta Metall. 15, 1453 (1967)Google Scholar
5. Vogl, G. and Sepiol, B., Acta Metall. Mater. 42, 3175 (1994)Google Scholar
6. Sepiol, B., Czihak, C., Meyer, A., Vogl, G., Metge, J., and Rüffer, R., Hyperfine Interact. 113, 449 (1998)Google Scholar
7. Kaisermayr, M., Combet, J., Ipser, H., Schicketanz, H., Sepiol, B., Vogl, G., Phys. Rev. B 61, 18 (2000)Google Scholar
8. Kao, C. R. and Chang, Y. A., Intermetallics 1, 237 (1993)Google Scholar
9. Athène, M., Bellon, P. and Martin, G., Phil. Mag. A 76, 3 (1997)Google Scholar
10. Farkas, D., Mutasa, B., Vaihlé, C., and Ternes, K., Modelling Simul. Mater. Sci. Eng. 3, 201 (1995)Google Scholar
11. Arita, M., Koiwa, M., and Ishioka, S., Acta Metall. 37, 1363 (1989)Google Scholar