A quantitative investigation of the two current conduction in nickel alloys

The electrical resistivity at 4.2K has been measured for ternary alloys based on nickel (Ni 97 A x B 3-x , where A and B denote metallic elements). These include Ni(AlCr), Ni(AuCo), Ni(AuRh), Ni(CoRh), Ni(CoRu), Ni(CrFe), Ni(CrMn), Ni(CrSn), Ni(CrTi), Ni(CuRh), Ni(CuRu), Ni(CuV), Ni(FePt), Ni(FeRe), Ni(RhRu) and Ni(RuTi). Large deviations from Matthiessen's rule i.e. the additivity of individual residual resistivities, are found to be a general phenomenon. The experimental results have been analysed in terms of Mott's two current conduction model; quantitative values for the spin sub-band resistivities are derived for each of the solute elements mentioned above. For a given solute metal these values are fairly independent of the set of ternary alloys from which they are determined, which presents a strong argument in favour of the applicability of the two current conduction model to nickel alloys.