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Simple Flexible Boundary Conditions for the Atomistic Simulation of Dislocation Core Structure and Motion

Published online by Cambridge University Press:  01 January 1992

Roberto Pasianot
Affiliation:
C.N.E.A., Av. Libertador 8250, Buenos Aires 1429, Argentina.
Eduardo J. Savino
Affiliation:
C.N.E.A., Av. Libertador 8250, Buenos Aires 1429, Argentina.
Zhao-Yang Xie
Affiliation:
Department of Materials Science and Engineering, VPI & SU, Blacksburg, VA 24061, USA.
Diana Farkas
Affiliation:
Department of Materials Science and Engineering, VPI & SU, Blacksburg, VA 24061, USA.
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Abstract

Flexible boundary codes for the atomistic simulation of dislocations and other defects have been developed in the past mainly by Sinclair [1], Gehlen et al.[2], and Sinclair et al.[3]. These codes permitted the use of smaller atomic arrays than rigid boundary codes, gave descriptions of core non-linear effects and allowed fair assessments of the Peierls stress for dislocation motion. Green functions (continuum or discrete) or surface traction forces were used to relax the boundary atoms.

A much simpler approach is followed here. Core and mobility effects at the boundary are accounted for by a dipole tensor centered at the dislocation line, whose components constitute six more parameters of the minimization process. Results are presented for [100] dislocations in NiAl. It is shown that, within the limitations of the technique, reliable values of the Peierls stress are obtained.

Type
Research Article
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

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