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Properties related to the glass transition of metallic melts are reviewed both on empirical ground and using the statistics of local minima in the potential energy landscape of the material. For metallic alloys some correlations have been disputed (e.g., the one between the Kauzmann and VFT temperatures). In the first part of this report these issues are considered and the possible reasons for either good or poor correlation are outlined. Then the relationship of the glass transition to mechanical properties (e.g., strength, moduli) is described with special attention to the failure mechanism of amorphous alloys via shear band propagation. The relationships are discussed for glass-forming alloys in comparison also with properties of other families of glass-formers.

Amorphous alloys are metastable phases which have generated considerable interest in recent years because of their promising properties. This review considers thermodynamic and kinetic aspects in the modelling of metallic amorphous phases. The relevant literature on the glass transition and the thermodynamics of amorphous phases is discussed in detail. The CALPHAD approach is used for thermodynamic modelling: it employs collected experimental data to obtain a reliable assessment of properties and metastable phase diagrams. Thermodynamic modelling of Short Range Order (SRO) in the liquid and glass transition is described and critically discussed with regard to rapid solidification experiments. Solid state amorphization and amorphization by means of deposition are also discussed. The extension to kinetics is then described, involving a number of modelling parameters. Predictions can thus be carried out of the Glass Forming Range (GFR), i.e. the composition range where glass formation is expected, according to different levels of approximation and for various processes. The importance of model parameters (thermodynamic driving force, interfacial energy, transport properties) is also assessed and some case studies (Cu–Zr, Fe–B and Cu–Mg–Y) are discussed. Recent results on the simulation of nanocrystals growth in amorphous materials are reported.

TGA, MS and DSC of a solid polymeric Ge hydride, obtained by γ-radiolysis of GeH 4 , are reported. Upon heating, it undergoes two successive weight losses at 463 and 1173 K. At 948 K two crystal phases are formed, one of them is pure germanium. Some comparisons with a-Ge: H produced via RF sputtering or glow discharge are reported.