A COMPARATIVE-STUDY OF METASTABLE ALLOY FORMATION BY ION MIXING AND THERMAL ANNEALING OF MULTILAYERS IN THE IMMISCIBLE Y-ZR SYSTEM

Amorphous alloys were formed in an immiscible Y-Zr system by ion mixin g and thermal annealing of multilayered films consisting of nine alter nate metal layers. In addition, two metastable crystalline phases, i.e . a fee Zr-rich and a fee Y-rich phase, were also obtained. A compatib le thermodynamic interpretation was proposed and illustrated by a Gibb s free energy diagram, which was constructed based on Miedema's model and included the free energy curve of the multilayered films possessin g excess interfacial energy. The formation mechanism of the metastable crystalline phase is also discussed in terms of the electronic struct ure as well as the growth kinetics. (C) 1998 Elsevier Science S.A.