Structural changes of Co_{66}Ni_{12} Si_9B_{13} amorphous alloy, stimulated by isochronal and isothermal annealing, were observed by means of the methods: electrical resistivity, Hall effect and X-ray diffraction. In the amorphous matrix at the temperature 673 K phasesα-Co and (Co,Ni)_5Si_2B are created, while at the temperature 773 K the phase (Co,Ni)_3B is formed. The structural phase transitions are related to abrupt decrease in electrical and Hall resistivities at the background of systematic decrease in these parameters values during the alloy transition from the amorphous to the crystalline state.
Glasses and amorphous materials show, coexisting with the sound waves, a variety of low energy excitations: tunneling, quasi-localized vibrations and relaxations. The latter two are observed well into the liquid state. Using molecular dynamics both were shown to be centred on more than ten atoms or molecular units, which form chain-like structures. With increasing frequency the interaction of the quasi-localized modes with the sound waves and with each other increases, they delocalize. However, even at the so-called boson peak frequency, where the sound waves become overdamped due to the interaction, the vibrations can be decomposed into local and extended modes. Closely correlated with the local vibrations are the local relaxations, which can be envisaged as collective jumps of groups of atoms. With rising temperature both the total jump length and the number of atoms participating increases. In the melt when single jumps are no longer resolved one still observes a collective motion of chains of atoms.
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