First-principles study of atomic ordering in fcc Ni-Cr alloys
2014 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 89, no 6, 064103- p.Article in journal (Refereed) Published
We investigate atomic ordering in fcc Ni-rich Ni-Cr alloys using first-principles techniques and statistical mechanics simulations based on the Ising Hamiltonian with effective cluster interactions computed by the screened generalized perturbation method (SGPM) and projector augmented wave (PAW) method. We demonstrate that effective chemical interactions in this system are quite sensitive to alloy composition and in fact to the specific configurational state. The chemical interactions for the high-temperature random state produce the atomic short-range order (SRO) with intensity maximum close to the (2/3 2/3 0) point of the reciprocal space in agreement with the previous first-principles investigation. A consistent with diffuse neutron scattering data maximum at the (1 1/2 0) position is obtained onlywhenwe take into consideration relatively small strain-induced interactions, which solves a long-standing inconsistency between theory and experiment in this system. The calculated transition temperature of order-disorder transition of Ni2Cr alloy, 880 K, is in good agreement with the experimental value of 863 K.
Place, publisher, year, edition, pages
2014. Vol. 89, no 6, 064103- p.
Short-Range Order, Inhomogeneous Electron-Gas, Disordered Binary Alloys, At-Percent Cr, Molecular-Dynamics, Diffuse-Scattering, Lattice-Parameter, Potential Model, Solid-Solution, Monte-Carlo
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-129342DOI: 10.1103/PhysRevB.89.064103ISI: 000332375400003ScopusID: 2-s2.0-84894694789OAI: oai:DiVA.org:kth-129342DiVA: diva2:651754
FunderSwedish Research Council, 15339-91505-33EU, European Research CouncilVinnova
QC 20140331. Updated from manuscript to article in journal.2013-09-272013-09-272014-03-31Bibliographically approved