Stabilization of supercooled liquid and bulk glassy alloys in ferrous and non-ferrous systems

We have found that an anomalous stabilization of supercooled liquid against crystallization occurs in a number of multicomponent alloys in Mg-, Ln-, Zr-, Pd- and Fe-based systems and enables the production of bulk glassy alloys. The lowest critical cooling rate for formation of a glassy phase is 0.10 K/s and the maximum sample thickness reaches about 100 mm. The stabilization is a universal phenomenon in the alloy liquid which satisfies the following three criteria of (1) multicomponent systems consisting of more than three elements, (2) atomic size ratios among the main constituent elements, and (3) negative heats of mixing among their elements. Bulk glassy alloys exhibit good mechanical properties, a supercooled liquid region, a superviscous flow and soft magnetic properties. (C) 1999 Elsevier Science B.V. All rights reserved.