New method for determination of hidden supercooled liquid region of TiZr-based amorphous alloys

TiZr-based metallic glass has a unique glass transition point. It is located at the top of the first exothermic peak instead of at the typical endothermic transformation reaction before the supercooled liquid region (∆Tx). It is hard to identify the glass transition temperature (Tg) and ∆Tx of these TiZr-based amorphous alloys by an exothermic-exothermic reaction. In this study, based on the physical characteristics of the free volume reduction, KWW-exponent β, the activation energy for structural relaxation (Qrelax), and the incubation time by isothermal annealing in DSC analyses, the exact Tg point can be precisely identified. As a result, the Ti42Zr42Ta3Si10Sn3 amorphous alloy presents an extra-wide supercooled liquid region (∆Tx), up to 149 K.