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arXiv · 0910.2544

Debye temperature of disordered bcc-Fe-Cr alloys

S. M. Dubiel·J. Cieslak·B. F. O. Costa
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Abstract

Debye temperature, TD, of Fe100-xCrx disordered alloys with 0 ~95 the Debye temperature is smaller than the one for the metallic iron, with a local minimum at x=~55 at which the relative decrease of TD amounts to ~12%. The first maximum coincides quite well with that found for the spin-waves stiffness coefficient, D0, while the pretty steep decrease observed for x>~95 which is indicative of a decoupling of the probe Fe atoms from the underlying chromium matrix is likely related to the spin-density waves which constitute the magnetic structure of chromium in that interval of composition. The harmonic force constant calculated from the Debye temperature of the least Fe-concentrated alloy (x>99.9) amounts to only 23% of the one characteristic of a pure chromium.

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S. M. Dubiel, J. Cieslak, B. F. O. Costa. 2009-10-14. Debye temperature of disordered bcc-Fe-Cr alloys. https://doi.org/10.1088/0953-8984%2F22%2F5%2F055402

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