First-principles theory of magnetically driven anomalous ordering in bcc Fe-Cr alloys

• Ab initio perturbation-theory techniques, such as the generalized perturbation method and magnetic force theorem, are used to determine the Heisenberg exchange interaction parameters and the effective cluster interactions in Fe-rich bcc Fe-Cr alloys in different magnetic states. We establish a direct connection between chemical and magnetic exchange interactions, as well as their dependence on the global magnetic state of the alloy. These findings have important implications for phase equilibria in magnetic alloys. In particular, we demonstrate that the experimentally reported concentration interval of anomalous ordering in Fe-Cr alloys is determined by the thermal history of the alloys through the value of global magnetization at the annealing temperature.

Subject headings

NATURVETENSKAP  -- Kemi -- Fysikalisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Physical Chemistry (hsv//eng)

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Materialteknik -- Metallurgi och metalliska material (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering -- Metallurgy and Metallic Materials (hsv//eng)

Keyword

exchange interactions

ferromagnetic metals

mossbauer

system

iron

decomposition

energies

Publication and Content Type

ref (subject category)

art (subject category)