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Dislocation interaction with C in alpha-Fe: a comparison between atomic simulations and elasticity theory

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 نشر من قبل Emmanuel Clouet
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف Emmanuel Clouet




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The interaction of C atoms with a screw and an edge dislocation is modelled at an atomic scale using an empirical Fe-C interatomic potential based on the Embedded Atom Method (EAM) and molecular statics simulations. Results of atomic simulations are compared with predictions of elasticity theory. It is shown that a quantitative agreement can be obtained between both modelling techniques as long as anisotropic elastic calculations are performed and both the dilatation and the tetragonal distortion induced by the C interstitial are considered. Using isotropic elasticity allows to predict the main trends of the interaction and considering only the interstitial dilatation will lead to a wrong interaction.



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