The Physics of Metals and Metallography

, Volume 111, Issue 3, pp 229–235 | Cite as

Evaluation of the Peierls stress for boundary dislocations

  • A. Ostapovets
  • V. Paidar
Theory of Metals

Abstract

The Peierls stress for 1/6〈111〉 twinning dislocations and 1/2〈111〉 perfect dislocations in a bcc structure has been evaluated. The calculations have been performed using the Peierls-Nabarro formalism. The Peierls stresses have been determined from the migration energy of a twin boundary γtbm and the energy of an unstable stacking fault γus. The values of γtbm and γus have been calculated using a set of generalized many-body interatomic potentials. The potentials were defined so as to ensure different stability of the bcc structure relative to other structures. It has been shown that this approach provides realistic values of the Peierls stress. The values of the Peierls stress for 1/6〈111〉 twinning dislocations are very sensitive to the model parameters, unlike those for 1/2〈111〉 perfect dislocations.

Keywords

Peierls stress twinning bcc 

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Copyright information

© Pleiades Publishing, Ltd. 2011

Authors and Affiliations

  • A. Ostapovets
    • 1
  • V. Paidar
    • 1
  1. 1.Institute of PhysicsAcademy of Sciences of Czech RepublicPragueCzech Republic

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