Ab-initio study of C and N point defects in the C14-Fe2Nb phase

College

College of Science

Department/Unit

Physics

Document Type

Article

Source Title

Journal of Alloys and Compounds

Volume

693

First Page

1315

Last Page

1322

Publication Date

1-1-2017

Abstract

Nb-alloying of steels can lead to the formation of topologically close-packed (TCP) phases, particularly Fe2Nb Laves and Fe7Nb6μ phases. The stability of these TCP phases is strongly affected by the presence of light elements like C and N. We calculate the solution energy of C and N in C14-Fe2Nb using density functional theory. N shows a strong preference to dissolve in larger interstitial voids while C shows a strong tendency to bind with a neighbouring Nb atom. The computed solution energies suggest N incorporation into Fe2Nb Laves phases while C is hardly soluble. The N-N interaction in Fe2Nb is strongly attractive and twice as strong as that of C-C. A comparison to C interstitials in the μ-Fe7Nb6phase shows similar dependence of the solution energy on the atomic environment. In order to aid future work, we additionally provide the coordinates of interstitial sites in all TCP phases (A15, Zr4Al3, C14, C15, C36, χ, μ, σ, M, P, δ and R.) in the supplementary material. © 2016 Elsevier B.V.

html

Digitial Object Identifier (DOI)

10.1016/j.jallcom.2016.10.030

Disciplines

Physics

Keywords

Niobium alloys; Aluminum alloys; Binary systems (Metallurgy); Zirconium alloys; Point defects

Upload File

wf_yes

This document is currently not available here.

Share

COinS