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The effect of high stress and high temperature on the structure of binary Al 90 Y 10 amorphous alloy has been investigated. Deformation of the alloy was carried out by high pressure torsion at room temperature; heating was produced up to 220 °C. It was revealed that both treatments leaded to the primary crystallization of the alloy. Produced Al nanocrystals were randomly distributed over the amorphous matrix. For the deformed sample no correlation between the location of nanocrystals and the positions of shear bands was observed. The nanocrystals formed due to the deformation were more euhedral and smaller in average size (~9 nm) than those produced by heating (~15 nm). We have shown that the size distributions for two states of the alloy differ from each other substantially. Based on the obtained data for Al nanocrystals size distribution we have concluded that the deformation-induced nanocrystallization in Al 90 Y 10 occurs by heterogeneous mechanism and the crystallization at the heating takes place by the mixed (heterogeneous and homogeneous) one.

A series of new Fe80−xCoxP14B6 (x=20, 25, 30, 32, 35, 40) glasses has been prepared by melt-spinning technique. The FeCo-based glasses crystallize via one stage eutectic reaction into a mixture of a-Fe (bcc) solid solution and a b.c.-tetragonal Fe3P-like phase at temperatures approx. 50 K higher than the Fe80−xNixP14B6 metallic glasses. The compositional dependence of the crystallization temperatures at constant rate heating of the FeCo-based glasses has a minimum at x=30 that correlates well with the values of the apparent activation energy of crystallization derived from the Kissinger analysis. The as-quenched Fe80−xCoxP14B6 ribbons within the range examined have superior saturation magnetization in comparison with that of the commercial Fe40Ni40P14B6 glass, for example the maximum value of the saturation magnetization Ms estimated from vibrating sample magnetometer measurements is as high as 153 emu/g (about 1.415 T, for a density of 7.42 g/cm3) for the Fe48Co32P14B6 alloy.