کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1593863 1002718 2011 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Thermo-physical properties of body-centered cubic iron–magnesium alloys under extreme conditions
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد دانش مواد (عمومی)
پیش نمایش صفحه اول مقاله
Thermo-physical properties of body-centered cubic iron–magnesium alloys under extreme conditions
چکیده انگلیسی

Using density functional theory formulated within the framework of the exact muffin-tin orbitals method, we investigate the thermo-physical properties of body-centered cubic (bcc) iron–magnesium alloys, containing 5 and 10 atomic % Mg, under extreme conditions, at high pressure and high temperature. The temperature effect is taken into account via the Fermi–Dirac distribution of the electrons. We find that at high pressures pure bcc iron is dynamically unstable at any temperature, having a negative tetragonal shear modulus (C′C′). Magnesium alloying significantly increases C′C′ of Fe, and bcc Fe–Mg alloys become dynamically stable at high temperature. The electronic structure origin of the stabilization effect of Mg is discussed in detail. We show that the thermo-physical properties of a bcc Fe–Mg alloy with 5% Mg agree well with those of the Earth’s inner core as provided by seismic observations.

Research highlights
► At the conditions of the Earth’s inner core, Mg stabilizes bcc iron dynamically.
► Fe0.95Mg0.05 reproduces the physical properties of the inner core.
► A bcc structured Fe–Mg alloy is a strong candidate model of the inner core.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solid State Communications - Volume 151, Issue 3, February 2011, Pages 203–207
نویسندگان
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