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Quasistatic measurements of room-temperature anelastic relaxation were used to characterize the properties of shear transformation zones (STZs) in amorphous Al 86.8 Ni 3.7 Y 9.5 in the dilute limit. Using a combination of nanoindenter cantilever bending and mandrel bend relaxation techniques, anelastic relaxation was measured over times ranging from 1 s to 3 Â 10 7 s. Direct spectrum analysis yields relaxation-time spectra, which display seven distinct peaks. The results were analyzed using a linear dashpot-and-spring model, combined with transition-state theory, to yield several STZ properties. These reveal a quantized hierarchy of STZs that differ from each other by one atomic volume. Potential STZs occupy a large volume fraction of the solid. They access their ergodic space, with the ratio of forward-to backward jump rates ranging from 1.03 to 4.3 for the range of stress values used.

Plastic deformation of amorphous Al 90 Fe 5 Gd 5 was investigated using nanoindentation and atomic force microscopy. While serrated flow was detected only at high loading rates, shear bands were observed for all loading rates, ranging from 1 to 100 nm/s. However, the details of shear-band formation depend on the loading rate.

Metastable solid solutions of Fe and Cu, which are immiscible in equilibrium, have been formed using high-energy ball milling of elemental powder mixtures. Single-phase face-centered-cubic (fee) solid solution was obtained for 0

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