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Atom probe tomography was used to characterize the distribution of atoms in bulk amorphous Pd 40 Ni 40 P 20 , Pd 40 Ni 40− x Fe x P 20 (0 x 50 Cu 50 ) 100− x P x ( x =16.5, 17.5, 19) alloys. The analyses were performed on samples cut from 7-mm diameter rods, which were prepared by quenching the melt at cooling rates of approximately 200 K/s. All the alloys were examined in the as-quenched condition. In the Pd 40 Ni 40− x Fe x P 20 glasses, the increase in Fe concentration causes a systematic increase in the clustering of palladium and ordering of phosphorus. The 20% Fe alloy exhibited a two-phase microstructure. The (Pd 50 Cu 50 ) 100− x P x glasses exhibited fine-scale phase separation into copper-enriched/phosphorus-depleted and copper-depleted/phosphorus-enriched regions. These observations follow from statistical analysis of the concentration frequency distributions, the composition enrichments of shells around each atom, and composition maps.

The formation of Fe-SiC composite, nanocrystalline solids through ball milling is reported. The effects of mechanical deformation, crystallite size and gaseous elements on the solid state reaction between Fe and SiC are also investigated. The formation of Fe3C after a long milling time is attributed to the kinetics of the reaction between nanocrystalline Fe and SiC.

A study of the amorphous phase reaction by mechanical alloying (MA) in different atmospheres has been carried out. Structural changes during milling were examined by means of X-ray analysis. The amounts of the gaseous elements absorbed by the powder particles during milling were determined by chemical analysis. It was found that there is almost no influence on the MA process either in an argon or a nitrogen atmosphere. During the milling process in air or an oxygen atmosphere, intermetallic compounds and oxides appeared, accompanying the formation of the amorphous phase. The intermetallic compounds appeared due to the presence of oxygen atoms.

Solid state amorphous phase change is studied in the Ni-Ti system. It is found that the crystalline to amorphous transition can be obtained by the mechanical alloying, or by annealing of the multilayers produced by mechanical alloying and/or cold rolling. Different products are found after the annealing of the multilayers. The activation energies and interdiffusion coefficients are obtained for the solid state amorphous reaction.

A recently proposed Gibbs-Bogoliubov type thermodynamic variational calculation, using the hard-sphere system as the reference system for supercooled metallic liquids, is extended to the supercooled-liquid states of Ga, Tl and Ti metals. The calculated results for the specific heat at constant pressure and the closely related quantities are examined. It appears that the liquid-glass transition is kinetic in nature and that the glass-forming ability of these metals is not low.