Amorphous (Zr–Y)<SUB>60</SUB>Al<SUB>15</SUB>Ni<SUB>25</SUB> Alloys with Two Supercooled Liquid Regions

Abstract

An amorphous phase exhibiting two distinguishable supercooled liquid regions was found in quaternary (Zr–Y)60Al15Ni25 alloys in which the main constituent elements of Zr and Y are immiscible in a solid state. The first- and second-stage supercooled liquid regions are observed in the temperature ranges of 640 to 664 K and 763 to 810 K, respectively, accompanied by the two-distinguishable exothermic peaks due to crystallization after the appearance of the supercooled liquid regions. The temperatures of the first- and the second-reactions appear to correspond to those for ternary Y60Al15Ni25 and Zr60Al15Ni25 amorphous alloys, respectively. The simultaneous dissolution of the immiscible Zr and Y elements is essential for the appearance of the two-stage supercooled liquid regions. From the appearance of the second-stage supercooled liquid region, it is concluded that the precipitation of the primary crystalline phase does not exert detrious influence on the appearance of the supercooled liquid region.