Calculations of Crystallization Temperature of Multicomponent Metallic Glasses

Abstract

A model for calculating crystallization temperature (T x ) of multicomponent metallic glasses is proposed by modifying the Miedema's model which is used for calculating T x of binary systems. The calculations were carried out for nearly 900 metallic glasses including 470 binary and 398 ternary alloys. In the present model, the cavity formation energy (ΔH for cavity ) for multicomponent metallic glasses was theoretically derived on the basis of the Miedema's model. The equation for expressing the relation between experimental T x and theoretical ΔH for cavity was statistically analyzed by the least-squares method, yielding T x = 4.16 x ΔH for cavity + 318. The binary and ternary systems tend to show different equations between Tx and ΔH for cavity . The inherent equation in each system was analyzed as simultaneous achievement of the increase in stability of metallic glasses and decrease in ΔH for cavity due to multicomponent alloying. Furthermore, the glass-forming ability was predicted by reduced crystallization temperature instead of reduced glass transition temperature. As a result, it was found that reduced crystallization temperature can be calculated close to reduced glass transition temperature except for Pt-, Pd- and La-based systems. It is of great importance that T x can be calculated for multicomponent metallic glasses by semi-empirical method.