Contraction and expansion effects on the substitution-defect properties of thirteen alloying elements in bcc Fe

Details Contraction and expansion effects on the substitution-defect properties of thirteen alloying elements in bcc Fe Contraction and expansion effects on the substitution-defect properties of thirteen alloying elements in bcc Fe

2010-08-18

arxiv.org/abs/1008.3001v1

Physics

Condensed Matter

Materials Science

Submitted to Journal of Nuclear Materials

Scientific paper

Proposed as blanket structural materials for fusion power reactors, reduced activation ferritic/martensitic (RAFM) steel undergoes volume expanding and contracting in a cyclic mode under service environment. Particularly, being subjected to significant fluxes of fusion neutrons RAFM steel suffers considerable local volume variations in the radiation damage involved regions. It is necessary to study the structure properties of the alloying elements in contraction and expansion states. In this paper we studied local substitution structures of thirteen alloying elements Al, Co, Cr, Cu, Mn, Mo, Nb, Ni, Si, Ta, Ti, V, and W in bcc Fe and calculated their substitutional energies in the volume variation range from -1.0% to 1.0%. From the structure relaxation results of the first five neighbor shells around the substitutional atom we find the relaxation in each neighbor shell keeps approximately uniform within the volume variation from -1.0% to 1.0% except those of Mn and the relaxation of the fifth neighbor shell is stronger than that of the third and forth, indicating that the lattice distortion due to the substitution atom is easier to spread in <111> direction than in other direction. The relaxation pattern and intensity are related to the size and electron structure of the substitutional atom. For some alloying elements, such as Mo, Nb, Ni, Ta, Ti and W, the substitutional energy decreases noticeably when the volume increases. Further analysis show that the substitutional energy comprises the energy variation originated from local structure relaxation and the chemical potential difference of the substitutional atom between its elemental crystalline state and the solid solution phase in bcc Fe. We think the approximately uniform relaxation of each neighbor shell around a substitutional atom give rise to a linear decrease in the substitutional energy with the increasing volume.

Affiliated with

Also associated with

No associations

Rating

Contraction and expansion effects on the substitution-defect properties of thirteen alloying elements in bcc Fe does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Contraction and expansion effects on the substitution-defect properties of thirteen alloying elements in bcc Fe, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Contraction and expansion effects on the substitution-defect properties of thirteen alloying elements in bcc Fe will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-504007