Hostname: page-component-8448b6f56d-sxzjt Total loading time: 0 Render date: 2024-04-19T22:59:19.562Z Has data issue: false hasContentIssue false
  • English
  • Français

The Behavior of Intersttitals in Irradiated Graphite

Published online by Cambridge University Press:  28 February 2011

D. F. Pedraza
D. F. Pedraza*
Affiliation:
Oak Ridge National Laboratory, Metals and Ceramics Division, Oak Ridge, TN 37831–6069
Get access

Abstract

A computer model is developed to simulate the behavior of self-interstitials with particular attention to clustering. Owing to the layer structure of graphite, atomistic simulations can be performed using a large parallelepipedic supercell containing a few layers. In particular, interstitial clustering is studied here using a supercell that contains two basal planes only. Frenkel pairs are randomly produced. Interstitials are placed at sites between the crystal planes while vacancies are distributed in the two crystal planes. The size of the computational cell is 20000 atoms and periodic boundary conditions are used in two dimensions. Vacancies are assumed immobile whereas interstitials are given a certain mobility.

Two point defect sinks are considered, direct recombination of Frenkel pairs and interstitial clusters. The clusters are assumed to be mobile up to a certain size where they are presumed to become loop nuclei. Clusters can shrink by emission of singly bonded interstitials or by recombination of a peripheral interstitial with a neighboring vacancy. The conditions under which interstitial clustering occurs are reported. It is shown that when clustering occurs the cluster size population gradually shifts towards the largest size cluster. The implications of the present results for irradiation growth and irradiation-induced amorphization are discussed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 235: Symposium A – Phase Formation and Modification by Beam-Solid Interactions , 1991 , 437
Copyright
Copyright © Materials Research Society 1992

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. Simmons, J.H.W., Radiation Damage in Graphite. Pergamon Press (1965)CrossRefGoogle Scholar
2. Kelly, B.T., Physics of Graphite. Applied Science Publishers (1981)Google Scholar
3. Niwase, K., Sugimoto, M., Tanabe, T. and Fujita, F.E., J. Nucl. Mater. 155–157, 303 (1988)CrossRefGoogle Scholar
4. Goggin, P.R. and Reynolds, W.N., Phil. Mag. 8, 265 (1963)CrossRefGoogle Scholar
5. Martin, D.G. and Henson, R.W., Phil Mag. 9, 659 (1964)CrossRefGoogle Scholar
6. Coulson, C.A., Senent, S., Herraez, M.A., Leal, M. and Santos, E., Carbon 3, 445 (1965)CrossRefGoogle Scholar
7. Wallace, P.R., Solid State Comm. 4, 521 (1966)CrossRefGoogle Scholar
8. Thrower, P.A. and Loader, R.T., Carbon 7, 467 (1969)CrossRefGoogle Scholar
9. Abrahamson, J. and Maclagan, R., Carbon 22, 291 (1984)CrossRefGoogle Scholar
10. Tanabe, T., Niwase, K. and Nakamura, K., J. Nucl. Mater. 168, 191 (1989)CrossRefGoogle Scholar
11. Thrower, P.A. and Mayer, R.M., phys. stat. sol. (a) 47, 11 (1978)CrossRefGoogle Scholar
12. Kaxiras, E. and Pandey, K.C., Phys. Rev. Lett 61, 2693 (1988)CrossRefGoogle Scholar
13. Pedraza, D.F., Clustering of Interstitials in Graphite. A Computer Simulation Study. Unpublished Report, ORNL, (1991)Google Scholar