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Effect of Non-Glide Components of the Stress Tensor on Deformation Behavior of Bcc Transition Metals

Published online by Cambridge University Press:  10 February 2011

K. Ito
Affiliation:
Department of Materials Science and Engineering, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
V. Vitek
Affiliation:
Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104-6272.
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Abstract

In this paper we demonstrate by atomic computer simulation that the non-Schmid slip behavior in bcc metals is a direct consequence of the non-planar core structure of 1/2<111> screw dislocations and their response to the applied stress tensor. The analysis has been carried out in detail for tantalum using the Finnis-Sinclair type central force many-body potentials. Two distinct non-Schmid effects have been discerned. The first is twinning-antitwinning slip asymmetry on {112} planes. This is an intrinsic property of the bcc structure and depends on the sense of the applied glide stress. The second non-Schmid effect is extrinsic and is controlled by the non-glide shear stresses perpendicular to the total Burgers vector on {110} planes into which the stress-free core of screw dislocations spread.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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References

1. Schmid, E. and Boas, W., Kristallplastizität, (Berlin: Springer, 1928).Google Scholar
2. Christian, J.W., Metall. Trans. A14, 1237 (1983).Google Scholar
3. Duesbery, M.S., in Dislocations in Solids, edited by Nabarro, F.R.N., (Elsevier: Amsterdam, 1989), p. 67.Google Scholar
4. Vitek, V., Prog. Mater. Sci., 36, 1 (1992).Google Scholar
5. Taylor, G., Prog. Mater. Sci., 36, 29 (1992).Google Scholar
6. Christian, J.W., in Proc. 3rd Int. Conf. on Reinstoffe in Wissenschaft und Technik, (Berlin, Akademie-Verlag, 1970), p. 263.Google Scholar
7. Sestak, B., in Proc. 3rd Int. Conf. on Reinstoffe in Wissenschaft und Technik, (Berlin, Akademie-Verlag, 1970), p. 221.Google Scholar
8. Kubin, L.P., Rev. Deform. Behav. Mater., 4, 181 (1982).Google Scholar
9. Dipersio, J. and Escaig, B., Phys. Stat. Sol. (a), 40, 393 (1977).Google Scholar
10. Sakai, A., Nishioka, Y. and Suzuki, H., J. Phys. Soc. Japan, 46, 881 (1979).Google Scholar
11. Duesbery, M.S. and Vitek, V., Acta Mater. 46, 1481 (1998).Google Scholar
12. Escaig, B., J. Phys. Paris, 29, 225 (1968).Google Scholar
13. Escaig, B., J. Phys. France, 35, C7 (1974).Google Scholar
14. Finnis, M.W. and Sinclair, J.E., Phil. Mag., A50, 45 (1984).Google Scholar
15. Ackland, G.J., and Thetford, R., Phil. Mag. A56, 15 (1987).Google Scholar