English

Study of phase stability in the $\sigma$-FeCr system

Materials Science 2011-03-23 v1

Abstract

Formation energy of the σ\sigma-phase in the Fe-Cr alloy system, ΔE\Delta E, was computed versus the occupancy changes on each of the five possible lattice sites. Its dependence on a number of Fe-atoms per unit cell, NFeN_{Fe}, was either monotonically increasing or decreasing function of NFeN_{Fe}, depending on the site on which Fe-occupancy was changed. Based on the calculated ΔE\Delta E - values, the average formation energy, <ΔE><\Delta E>, was determined as a weighted over probabilities of different atomic configurations. The latter has a minimum in the concentration range where the σ\sigma-phase exists. The minimum in that range of composition was also found for the free energy calculated for 2000 K and taking only the configurational entropy into account.

Keywords

Cite

@article{arxiv.1103.4260,
  title  = {Study of phase stability in the $\sigma$-FeCr system},
  author = {J. Cieslak and J. Tobola and S. M. Dubiel},
  journal= {arXiv preprint arXiv:1103.4260},
  year   = {2011}
}