Crystallization behaviour of amorphous Zr1-xCox alloys with 0.20 ≤ x ≤ 0.41

The crystallization of melt-spun amorphous Zr_1-xCo_x alloys with 0.20 ≤ x ≤ 0.41 has been studied under both isothermal and non-isothermal conditions by use of DSC-technique. Up to three peaks were observed. The crystallization temperature varies with composition from 631 K for x = 0.20 to 746 K for x = 0.41. Isothermal annealing of x = 0.41 shows that the kinetics of the crystallization can be described by the Johnson-Mehl-Avrami equation with n ≈ 2.85 at lower annealing temperatures (712.5 – 725 K) while in the temperature range 725 K to 740 K n increases with increasing annealing temperature. The phases formed during the crystallization process have been identified by means of X-ray diffraction techniques and electron microscope studies. For compositions around x = 0.33 microcrystalline phases are formed upon crystallization.