Hostname: page-component-77c89778f8-9q27g Total loading time: 0 Render date: 2024-07-17T00:21:08.110Z Has data issue: false hasContentIssue false

On The Mechanism of Interstitial Cluster Migration in α -FE

Published online by Cambridge University Press:  15 February 2011

A.V. Barashev
Affiliation:
Materials Science and Engineering, Department of Engineering, The University of Liverpool, Brownlow Hill, Liverpool, L69 3GH, UK, a.barashev@liv.ac.uk
Yu.N. Osetsky
Affiliation:
Materials Science and Engineering, Department of Engineering, The University of Liverpool, Brownlow Hill, Liverpool, L69 3GH, UK
D.J. Bacon
Affiliation:
Materials Science and Engineering, Department of Engineering, The University of Liverpool, Brownlow Hill, Liverpool, L69 3GH, UK
Get access

Abstract

Recent molecular dynamics (MD) computer simulations have shown that clusters consisting of up to a few tens of self-interstitial atoms (SIAs) are highly mobile along closed-packed crystallographic directions in pure copper and iron. This effect has important consequences for microstructure evolution in irradiated metals and so it is desirable to investigate the mechanisms of the cluster motion. In the present paper the results of MD modelling of the thermally-activated motion of clusters of 3, 9 and 17 SIAs in α-Fe in the temperature range from 90 to 1400 K are analyzed. The extensive MD data has enabled the migration of clusters, as well as that of individual SIAs in the clusters, to be treated with high statistical accuracy. The correlation between the motion of the centre of gravity of a cluster and the jumps of individual SIAs in the cluster is revealed. It is found that the SIAs in a cluster jump almost independently and their jump frequency depends on the number of SIAs in the cluster. This leads to a simple relationship between the jump frequency of a cluster and the number of SIAs in it. The cluster jump frequency exhibits a deviation from the Arrhenius relationship. The reason for this is discussed.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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. Grasse, D., Guerard, B.von and Peisl, J., J. Nucl. Mat. 120, 304 (1984); R.Rauch, J.Peisl, A.Schmalzbauer and G.Wallner, 168, 101 (1989).Google Scholar
2. Bacon, D.J., Calder, A.F. and Gao, F., J. Nucl. Mat. 251, 1 (1997).Google Scholar
3. Rubia, T.Diaz de la and Guinan, M.W., Phys. Rev. Lett. 66, 2766 (1991).Google Scholar
4. Foreman, A.J.E., Phythian, W.J. and English, C.A., Phil. Mag. A66, 651 (1992).Google Scholar
5. Wirth, B.D., Odette, G.R., Maroudas, D. and Lucas, G.E., J. Nucl. Mat. 244, 185 (1997); R.Stoller, G.R.Odette and B.D.Wirth, Phil. Mag.A66651 1992, 251,49 (1997).Google Scholar
6. Whiting, B.J. and Bacon, D.J. in Microstructure Evolution During Irradiation, edited by Robertson, I.M., Was, G.S., Hobbs, L.W. and Rubia, T.Diaz de la (Mat. Res. Soc. Proc. 439, Warrendale, Pennsylvania, 1997) pp.384394.Google Scholar
7. Osetsky, Yu.N., Serra, A., and Priego, V. in Diffusion Mechanisms in Crystalline Materials, edited by Mishin, Yu., Yogl, G., Cowern, N., Catlow, R., Farcas, D. (Mat. Res. Soc. Proc. 527, Warrendale, Pennsylvania, 1998) pp.5968.Google Scholar
8. Woo, C.H. and Singh, B.N., Phil. Mag. A65, 889 (1992); B.N.Singh and A.J.E.Foreman, (Mat. Res. Soc. Proc. 527 Warrendale, Pennsylvania, 1998) pp.59 68. A66, 975 (1992).Google Scholar
9. Trinkaus, H., Singh, B.N. and Foreman, A.J.E., J. Nucl. Mat. 249, 91 (1997); B.N.Singh, S.I.Golubov, H.Trinkaus, A.Serra, Yu.N.Osetsky and A.V.Barashev, B.N.Singh and A.J.E.Foreman, (Mat. Res. Soc. Proc. 527 Warrendale, Pennsylvania, 1998) pp.59 68. A66, 975 (1992). 251, 107 (1997).Google Scholar
10. Ackland, G.J., Bacon, D.J., Calder, A.F. and Harry, T., Phil. Mag. A75, 713 (1997).Google Scholar