In situ formation of two glassy phases in the Nd–Zr–Al–Co alloy system

The Nd–Zr–Al–Co alloy system undergoes metastable liquid phase separation over a wide composition range during quenching and subsequently solidifies into two different Nd-rich and Zr-rich amorphous phases. As-quenched samples consist of two amorphous phases of spherical shape with a wide range of length scale (from several nm to μm), and exhibit two distinct exothermic reactions during continuous heating. Viscosity and magnetic properties have been measured to identify potential practical applications of phase-separating metallic glasses.