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High entropy alloys (HEAs), or concentrated solid solution alloys, are chemically complex metallic solid solutions in which five or more elements occupy the same crystallographic lattice sites with nearly equal compositions. The high degree of chemical disorder gives rise to considerable local lattice distortions, atomic-level stresses, and complex electronic structure, resulting in interesting properties. We calculated the electronic structure and the atomic-level stresses of AlxTiyZryPdyCuyNiy, x = 0.5, y = 1 (Al0.5TiZrPdCuNi) HEA in the glassy phase using the density functional theory (DFT) approach. We also briefly discuss the electronic structure in its crystalline phase. Whereas it has been reported recently that the crystalline phase of this HEA is obtained as a metastable phase during the crystallization of a glassy phase, the crystalline phase was found to be unstable at T = 0 in the DFT calculation. For this reason, we focus mainly on the glassy phase in this work. The importance of charge transfer among elements on the atomic-level pressure and the role for atomic-level stresses to characterize the electronic and structural heterogeneity are discussed. [ABSTRACT FROM AUTHOR]

Metallic melts above the liquidus temperature exhibit nearly Arrhenius-type temperature dependence of viscosity. On cooling below the equilibrium liquidus temperature metallic melts exhibit a non-Arrhenius temperature dependence of viscosity characterized by liquid fragility phenomenon which origin is still not well understood. Structural changes and vitrification of the Pd42.5Cu30Ni7.5P20 liquid alloy on cooling from above the equilibrium liquidus temperature are studied by synchrotron radiation X-ray diffraction and compared with the results of first-principles calculations. Subsequent analysis of the atomic and electronic structure of the alloy in liquid and glassy states reveals formation of chemical short-range order in the temperature range corresponding to such a non-Arrhenius behavior. The first-principles calculations were applied to confirm the experimental findings. [ABSTRACT FROM AUTHOR]

Discusses a study which determined the spatial magnetic correlation in nickel-manganese base amorphous alloys. Measurement of the nuclear and magnetic parts of the structure factor of the alloy; Discussion of pulsed neutron scattering; Effects of annealing on the compositional short-range order.

Presents a study which examined the consequences for magnetism of icosahedral site symmetry and of long-range icosahedral ordering as found in quasicrystals. Factors that were predicted for long-range icosahedrally ordered magnets; Description of icosahedral quasicrystals; Reason for using the term quasicrystals; Examples of crystal structures that exist with local icosahedral structural units.

Presents a study that investigated the relation between anelasticity and the relaxation behavior of the Curie temperature in amorphous alloys. Information on the kinetics of the Curie temperature relaxation; Effect of the preannealing temperature on the kinetics of the Curie temperature; Determination of the saturation value of the Curie temperature against the inverse of the annealing temperature.

Presents a study that investigated the creep-induced magnetic anisotropy in metallic glass. Information on a computer model of the creep deformation; Effect of the simulated structural anisotropy on the magnetic anisotropy of metallic glasses; Analysis of magnetic anisotropy caused by bond-orientational anisotropy.

Discusses the results of a synchrotron x-ray scattering study. Structural anisotropy of sputter-deposited amorphous terbium-iron-cobalt thin films; Mechanisms which lead to the observed structural and magnetic anisotropies; Observed structural anisotropy.

Reports on the first direct observation of structural anisotropy in the magneto-optical amorphous thin films by x-ray diffraction measurements. Measurement of the scattering intensities of the thin films; Annealing effect.

Presents a study that proposed an evidence of structural anisotropy due to anelastic polarization in an amorphous alloy. Background on creep-induced magnetic anisotropy; Determination of structural anisotropy induced by creep deformation; Analysis of the diffraction spectra of the amorphous alloy.

Presents the abstract of a study by Dmowski et al which examined the local structure of aluminum[sub75](manganese, chromium, ruthenium, rhenium, silicon)[sub25] icosahedral alloys with pulsed neutron scattering.