Prediction of the Glass-Forming Ability of Cu-Zr Binary Alloys

Based on the random solution model and stoichiometric intermetallic compound Gibbs free energy model, the driving forces for the crystallization from the undercooled liquid of Cu-Zr binary alloys were evaluated by using Turnbull and Thompson-Spaepen (TS) approximate equations, respectively. Using Davies-Uhlmann kinetic formulations within the frame of continuous nucleation theory (CNT), two groups of time-temperature transformation (TTT) curves of eight compositions of the binary system were calculated, and thereby the corresponding critical cooling rates were obtained. It is shown that both groups of the calculated values for the glass-forming ability (GFA) are in good agreement with the experimental data. The critical cooling rates evaluated by using TS equation are in good agreement with the experimental data compared with that evaluated by using Turnbull equation.