Mg–Ni–La Amorphous Alloys with a Wide Supercooled Liquid Region

Abstract

New Mg–Ni–La amorphous alloys exhibiting the glass transition phenomenon were found to form in a wide compositional range of 10 to 40 at% Ni and 5 to 30 at%La by the melt-spinning technique. The glass transition temperature (Tg) increases from 427 to 453 K with increasing La content while no distinct change of Tg with Ni content is seen. The temeprature span ΔTx(=Tx−Tg) between Tg and onset tempera-ture of crystallization (Tx) increases first with increasing Ni and La content, shows the largest value of 58 K for Mg50Ni30La20, and then decreases. This ΔTx value is larger than that for Pd-based amorphous alloys, being comparable to that for a Pt60Ni15P25 amorphous alloy which exhibits the widest Tx among amorphous metallic materials. Specific heats of the amorphous solid and supercooled liquid were also determined for the Mg50Ni30La20 amorphous alloy.