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The effect of continuous heating and isothermal heat treatments on ductile Cu 60 Zr 20 Ti 20 amorphous ribbons was monitored by differential scanning calorimetry, x-ray diffraction, synchrotron radiation transmission, and high-resolution transmission electron microscopy. Upon continuous heating, the alloy exhibited a glass transition, followed by a supercooled liquid region and two exothermic crystallization stages. Decomposition of the amorphous phase was also observed. The first crystallization stage resulted in the formation of a nanocomposite structure with hexagonal Cu 51 Zr 14 particles embedded in the amorphous matrix, while in the second crystallization stage hexagonal Cu 2 TiZr-like phase was precipitated. The released enthalpies were 19 J/g and 30 J/g for each crystallization stage. Crystallization kinetics was studied by the classical nucleation theory. Deviations from the Johnson-Mehl-Avrami-Kolmogorov theory may be explained by the contribution of the decomposition of the amorphous matrix.

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Bulk amorphous Fe 65.5 Cr 4 Mo 4 Ga 4 P 12 C 5 B 5.5 rods with diameters of 1.5-3 mm were prepared by copper mold casting. Besides casting, bulk amorphous Fe 77 Al 2.14 Ga 0.86 P 8.4 C 5 B 4 Si 2.6 samples in the shape of discs (diameter of 10 mm and thickness of 3 mm) were prepared from melt-spun ribbons by high-energy ball milling and subsequent compaction of the resulting powders in the supercooled liquid region. The ascast amorphous FeCrMoGaPCB samples exhibit a low coercivity, below 10 A·m −1 . In the case of the FeAlGaPCBSi alloy, the milling-induced stress causes significant differences in coercivity between the ribbons and the powders. The relatively low coercivity of about 5-10 A·m −1 characteristic for the melt-spun ribbons increases after 1 hour of ball milling to a value of about 2200 A·m −1 . Subsequent annealing of the ball-milled powders leads to a decrease of H c by a factor of 10 to about 220-250 A·m −1 . The bulk samples prepared by hot pressing of the crushed ribbons show a coercivity of about 120-140 A·m −1 . For both alloys, thermal stability measurements show a distinct glass transition, followed by a supercooled liquid region of 60 K for Fe 65.5 Cr 4 Mo 4 Ga 4 P 12 C 5 B 5.5 and of 30 K for Fe 77 Al 2.14 Ga 0.86 P 8.4 C 5 B 4 Si 2.6 . For the Fe 65.5 Cr 4 Mo 4 Ga 4 P 12 C 5 B 5.5 alloy, crystallization of the amorphous phase as observed by in-situ X-ray diffraction measurements in transmission configuration occurs via the formation of a metastable intermediate phase. The phases observed in the crystalline state obtained by heating do not correspond to those occurring after slow cooling.

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