The basic polyhedral clusters, the optimum glass formers, and the composition-structure-property (glass-forming ability) correlation in Cu-Zr metallic glasses J. Appl. Phys. 107, 063508 (2010) We studied atomic and electronic structures of binary Cu-Zr metallic glasses (MGs) using combined experimental and computational methods including X-ray absorption fine structure spectroscopy, electrical resistivity, thermoelectric power (TEP) measurements, molecular dynamics (MD) simulations, and ab-initio calculations. The results of MD simulations and extended X-ray absorption fine structure analysis indicate that atomic order of Cu-Zr MGs and can be described in terms of interpenetrating icosahedral-like clusters involving five-fold symmetry. MD configurations were used as an input for calculations of theoretical electronic density of states (DOS) functions which exhibits good agreement with the experimental X-ray absorption near-edge spectra. We found no indication of minimum of DOS at Fermi energy predicted by Mott's nearly free electron (NFE) model for glass-forming alloys. The theoretical DOS was subsequently used to test Mott's model describing the temperature variation of electrical resistivity and thermoelectric power of transition metal-based MGs. We demonstrate that the measured temperature variations of electrical resistivity and TEP remain in a contradiction with this model. On the other hand, the experimental temperature dependence of electrical resistivity can be explained by incipient localization of conduction electrons. It is shown that weak localization model works up to relatively high temperatures when localization is destroyed by phonons. Our results indicate that electron transport properties of Cu-Zr MGs are dominated by localization effects rather than by electronic structure.We suggest that NFE model fails to explain a relatively high glass-forming ability of binary Cu-Zr alloys. V C 2014 AIP Publishing LLC.[http://dx

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Nominal Y0.3B&.6Na0.1CuO~6 thin films were prepared with small grains having an orientation of the c axis perpendicular to the MgO substrate. The electrical resistivity and the thermoelectric power in the absence and in the presence of a magnetic field are reported. The magnetic field dependence of the irreversibility line is discussed. The role of the field for disentangling intragrain and intergrain effects in both coefficients is emphasized.

We present a model describing the temperature dependence of the resistivity of the Al92Sm8 system during formation of fcc-Al nanocrystals. We take into consideration changes in resistivity of the amorphous phase due to the changing content of Al, the varying density of the crystallization nuclei, the creation of the Sm layer on the grain surface and decomposition appearing during annealing of the amorphous phase. Our calculations exhibit a better agreement with experimental electrical resistivity data for the nanocrystallization model considering previous decomposition of amorphous structure and formation of a monatomic Sm layer on grain boundaries than for a model of nanocrystallization on quenched-in nuclei with growth controlled by diffusion with a diffusion field impingement.

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