Amorphous Formation in an Undercooled Binary Ni-Si Alloy under Slow Cooling Rate

High undercooling up to 392 K was achieved in eutectic Ni70.2Si29.8 alloy melt by using glass fluxing combined with cyclic superheating.A small quantity of amorphous phase was obtained in bulk eutectic Ni70.2Si29.8 alloy when undercooling exceeds 240 K under slow cooling conditions (about 1 K/s).The amorphous phase was confirmed by high-resolution transmission electron microscopy and differential scanning calorimetry.