Energy Changes and the Lattice Resistance

Clegg, W.J.; Vandeperre, L.; Pitchford, J.E.

doi:10.4028/www.scientific.net/KEM.317-318.271

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Home Key Engineering Materials The Science of Engineering Ceramics IIIEnergy Changes and the Lattice Resistance

Energy Changes and the Lattice Resistance

Abstract:

The aim of this paper is to study the effect of relaxing the assumption in the Peierls analysis that the dislocation must be wide compared to the atom spacing. To do this the use of the continuum description of the in-plane strains caused by the presence of an edge dislocation is replaced by an atomistic interaction taken to be linear elastic. It is found that in this case the inplane interactions give a contribution to the overall misfit energy changes that are not present in the Peierls analysis because of the use of a continuum approach. This contribution modifies these energy changes so that the total misfit energy is a minimum at the conventional low energy positions (whereas in the Peierls analysis it is a maximum) and gives values of the Peierls stress in reasonable agreement with those measured.

Info:

Periodical:

Key Engineering Materials (Volumes 317-318)

Main Theme:

The Science of Engineering Ceramics III

Edited by:

T. Ohji, T. Sekino and K. Niihara

Pages:

271-276

DOI:

https://doi.org/10.4028/www.scientific.net/KEM.317-318.271

Citation:

W.J. Clegg et al., "Energy Changes and the Lattice Resistance", Key Engineering Materials, Vols. 317-318, pp. 271-276, 2006

Online since:

August 2006

Authors:

W.J. Clegg, L. Vandeperre, J.E. Pitchford

Keywords:

Ceramic, Dislocation Glide, Lattice Resistance, Plastic Flow

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$38.00

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References

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[2] R. Peierls: Proc. Phys. Soc., Vol 52 (1940) p.34.

[3] K. Ohsawa: Philos. Mag. A Vol 69 (1994) p.171.

[4] H.B. Huntington: Proc. Phys. Soc. B Vol 68 (1955) p.1043.

[5] J.N. Wang: Acta mater. Vol 44 (1996) p.1541.

[6] J.W. Christian and V. Vitek: Rep. Prog. Phys. Vol 33 (1970) p.307.

[7] J.P. Hirth and J. Lothe: Theory of Dislocations (McGraw-Hill, USA 1968).

[8] J. Frenkel: Z. Phys. Vol 37 (1926) p.572.

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139

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155

Dislocation Dynamics Simulations

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