Dependence of electrical resistivity of Fe-Al alloys on composition

A series of binary Fe-Al alloys containing 20-40 at.% Al, having ordered D0(3) (Fe(3)Al) or B2 (FeAl) structure, was cast from pure elements. For a comparison, specimens were also prepared from corresponding complex Fe-Al alloys with additional alloying elements of C, Cr, Ti, Zr and B. All specimens were investigated in two states, as-prepared and heat treated (723 K/120h). Electrical resistivity was measured at 291 K (RT) and 77 K (liquid N(2)), respectively, by means of usual potentiometric method. Electrical resistivity data of these series of Fe-Al alloys with and without additional alloying elements are presented and discussed. Differences between resistivity of binary and complex alloys are mainly due to substitution of Fe by Cr in the D0(3) matrix. The addition of C in alloys with B2 structure lowers the resistivity of the matrix due to K-phase Fe(3)AlC(x) precipitation. A strong correlation was observed between the temperature dependent part of electrical resistivity and long-range order in pure binary Fe Al alloys. (C) 2010 Elsevier Ltd. All rights reserved.