Alloying effects on the elastic parameters of ferromagnetic and paramagnetic Fe from first-principles theory
2011 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 110, no 7, 073707- p.Article in journal (Refereed) Published
The elastic properties of paramagnetic face-centered-cubic (fcc) Fe(1-x)M(x) (M = Al, Si, V, Cr, Mn, Co, Ni, and Rh; 0 <= x <= 0.1) random alloys are investigated using the exact muffin-tin orbitals density functional method in combination with the coherent-potential approximation. We find that the theoretical lattice parameter of fcc Fe is strongly enlarged by Al, V, and Rh and slightly reduced by Si, Cr, and Co, while it remains nearly constant with Mn and Ni. Both positive and negative alloying effects appear for the elastic constants C(ij)(x) of fcc Fe. These findings are in contrast to those obtained for ferromagnetic body-centered-cubic (bcc) Fe alloys, where all alloying elements considered here are predicted to enlarge the lattice parameter and decrease the C(11)(x) and C(12)(x) elastic constants of bcc Fe. With some exceptions, alloying has much larger effects on ferromagnetic bcc alloys than on paramagnetic fcc ones. Based on the theoretical elastic parameters of the paramagnetic fcc and ferromagnetic bcc phases, simple parameterizations in terms of chemical composition of the equilibrium lattice constants, single-crystal elastic constants, and polycrystalline elastic moduli of Fe-based alloys are presented.
Place, publisher, year, edition, pages
2011. Vol. 110, no 7, 073707- p.
coherent-potential approximation, initio molecular-dynamics, total-energy calculations, wave basis-set, lattice-dynamics, single-crystals, iron, constants, metals, model
IdentifiersURN: urn:nbn:se:kth:diva-46855DOI: 10.1063/1.3644907ISI: 000295883000055ScopusID: 2-s2.0-80054969961OAI: oai:DiVA.org:kth-46855DiVA: diva2:454356
FunderSwedish Research Council
QC 201111072011-11-072011-11-072011-11-23Bibliographically approved