American Journal of Engineering and Applied Sciences

Cold Crystallization Behavior of a Zr44-Ti11-Cu10-Ni10-Be25 Metal Glassy Alloy

Raffaella Aversa, Daniela Parcesepe, Francesco Tamburrino, Antonio Apicella and Florian Ion Tiberiu Petrescu

DOI : 10.3844/ajeassp.2018.1005.1022

American Journal of Engineering and Applied Sciences

Volume 11, Issue 2

Pages 1005-1022

Abstract

Liquid crystals, a substance that flows like a liquid but has some degree of ordering in the arrangement of its molecules. "Depending on temperature or the presence of an electric potential difference, molecules in a liquid crystal can either be randomly, partially or completely aligned."Isothermal cycles of the metalized metallic alloy Zr44-Ti11-Cu10-Ni10-Be25 (cold crystallization obtained by heating the glassy glass samples) were investigated in this study in the metastable state of the overheated liquid metal at elevated temperatures above the glass transition. Complex crystallizing behaviors with multiple and selective exothermic peaks crystallization of higher mobility atoms from an alloy induced by isothermal annealing have been observed to result in an experimentally observed increase in temperature required to induce glass metal relaxation (vitreous transition). Dynamic DSC analysis indicated that only two atomic species present in the metastable liquid are involved in the recrystallization process below 450-470°C. Isothermic isolation in the temperature range between 400° and 450°C was chosen for subsequent investigation of the thermal kinetics occurring in the supercooled chilled liquid. The activation energies associated with the two crystallization processes are, respectively, -181 kJ/mol and -262 kJ/mol.

Copyright

© 2018 Raffaella Aversa, Daniela Parcesepe, Francesco Tamburrino, Antonio Apicella and Florian Ion Tiberiu Petrescu. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.