Structure and crystallization kinetics of a Cu_(50)Zr_(45)Ti_5 glassy alloy

摘要

The crystallization kinetics and structure changes in a melt-spun Cu_(50)Zr_(45)Ti_5 glassy alloy on heating were investigated by X-ray diffractometry, transmission electron microscopy, differential scanning calorimetry and differential isothermal calorimetry. The glassy phase in the Cu_(50)Zr_(45)Ti_5 alloy was crystallized forming Cu_(10)Zr_7 and CuZr_2 phases upon thermal annealing. The activation energy for crystallization obtained by the Arrhenius equation was 435 kJ/mol. The crystallization process took place by nucleation and growth mechanism, and an Avrami exponent of about 3.3 may indicate a three-dimensional interface-controlled growth of nuclei with a decreasing nucleation rate.