Paper Title:
Effect of C on Vacancy Migration in α-Iron
  Abstract

Carbon atoms are always present in Fe-based materials, either as impurities even in high purity samples or as an intrinsic constituent in steels. Density Functional Theory calculations have been performed to study the interaction between C atoms and vacancies (V) in α-Fe. We find that the formation of VCn complexes is energetically favourable for n ≤ 3, with VC2 being the most stable one. The energy gain corresponding to the clustering reaction VCn-1 + C → VCn depends mainly on the strength of C-C covalent bonds. The vacancy diffusivity is shown to be significantly modified by the formation of vacancy-carbon complexes, exhibiting non-Arrhenius behaviour. Effective vacancy diffusion coefficients in α-Fe are calculated as a function of temperature and carbon content using a simplified thermodynamic model. The results are discussed in detail in the limiting case of excess of C with respect to vacancies.

  Info
Periodical
Solid State Phenomena (Volume 139)
Edited by
Veena Tikare, Graeme E. Murch, Frédéric Soisson and Jeung Ku Kang
Pages
157-164
DOI
10.4028/www.scientific.net/SSP.139.157
Citation
C. C. Fu, E. Meslin, A. Barbu, F. Willaime, V. Oison, "Effect of C on Vacancy Migration in α-Iron", Solid State Phenomena, Vol. 139, pp. 157-164, 2008
Online since
April 2008
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Liudmila V. Selezneva, Andrei V. Nazarov
Abstract:This work is devoted to simulation of interstitial atom diffusion in fcc metals with point defects. We used the molecular static and the...
1275
Authors: Boris S. Bokstein, Alexander Epishin, Vladimir Esin, Mikhail I. Mendelev, Alexey O. Rodin, Sergey N. Zhevnenko
Abstract:Three cross diffusion-stresses effects are considered: mobility-stress effect, flux-stress effect and vacancy-stress effect. The value of...
79
Authors: Liudmila V. Selezneva, Andrei V. Nazarov
Abstract:This work is devoted to simulation of potential barrier spectrum for hydrogen atom and vacancy jumps in fcc- and bcc- metals taking into...
133
Authors: Leyla E. Isaeva, D.I. Bazhanov, S.S. Kulkov, S.E. Kulkova, Igor A. Abrikosov
Abstract:In this paper we have studied from first-principles the effect of magnetism on the hydrogen-metal interaction and the binding properties of...
19
Authors: Mikhail I. Mendelev, Alexey O. Rodin, Boris S. Bokstein
Abstract:We present results of the molecular dynamics study of Al selfdiffusion, Al and Fe diffusion in Al-Fe dilute alloys. We found that addition of...
733