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The atomic distribution in amorphous FeZr alloys is found to be close to random, nevertheless, the composition can not be viewed as being homogenous at the nm-scale. The spatial variation of the local composition is identified as the root of the unusual magnetic properties in amorphous Fe 1 - x Zr x alloys. The findings are discussed and generalised with respect to the physical properties of amorphous and crystalline materials. [ABSTRACT FROM AUTHOR]

Since the early days of phase diagram calculation, the CALPHAD community has accepted a method of data assessment that is based on using Gibbs energy expressions for stoichiometric compounds that consist of a part that represents the contributions of the reference components, the so-called Neumann-Kopp sum, and a part that represents the Gibbs energy of formation. Usually, the latter consists only of a simple A + B * T term, which implies on the one hand that enthalpy and entropy of formation of a compound are temperature independent, and on the other, that the heat capacity of the respective compound is given by the Neumann-Kopp sum of the Cps of the constituents. In most cases this method yields acceptable results, also for the heat capacity. However, if certain elementary components are involved, this is not so. The paper highlights the problem outlining a remedial treatment that can be applied to problematic heat capacity functions present in pre-existing assessments, and thus giving a suggestion of how to prevent the problem in the future. [ABSTRACT FROM AUTHOR]

Vanadium (V)–aluminum (Al)–carbon (C) thin films were deposited on Al2O3 (11̄20) substrates at 500 °C by direct current magnetron sputtering using a powder metallurgical composite target with 2:1:1 MAX phase stoichiometry. Transmission electron microscopy (TEM) and x-ray diffraction results suggest that a hexagonal Al-containing vanadium carbide solid solution (V,Al)2Cx was formed. The films exhibited a strong basal plane texture. The lattice parameter of the hexagonal solid solution was dependent on the annealing temperature: the c lattice parameter decreased by 3.45% after annealing for 1 h at 750 °C compared to the as-deposited film. Based on the comparison between experimental and theoretical lattice parameter data, it is reasonable to assume that this annealing-induced change in lattice parameter is a consequence of atomic ordering. Meanwhile, the formation of V2AlC MAX phase was observed at 650 °C and phase-pure V2AlC was obtained at 850 °C. TEM images support the notion that V2AlC forms by nucleation and growth. [ABSTRACT FROM AUTHOR]