FIRST-PRINCIPLES CALCULATION OF THE SITE SUBSTITUTION OF TRANSITION METAL ELEMENTS IN THE NbCr2 LAVES PHASE
Jian Sun
上海交通大学材料学院
Cite this article:
Jian Sun. FIRST-PRINCIPLES CALCULATION OF THE SITE SUBSTITUTION OF TRANSITION METAL ELEMENTS IN THE NbCr2 LAVES PHASE. Acta Metall Sin, 2006, 42(8): 801-804 .
Abstract In this paper, the site occupancy of transition metal elements, such as V, Ti and W, in the C15 NbCr2 Laves-phase compound were investigated by the full-potential linearized augmented plane-wave-method within the generalized gradient approximation. The calculated results show that there are different site substitution behaviors for these alloy elements in NbCr2. V preferentially substitutes the Cr sites, and W has a weak site preference on the Cr site. Ti preferentially occupies the Nb sites in NbCr2. The calculations of the heat of formation show that only V occupying the Cr sites and Ti occupying the Nb sites can stabilize NbCr2 Laves phase. The site substitution behaviors of those transition metal elements in NbCr2 are also discussed with the calculated electronic structure of the ternary Laves phases.
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