Crystallization of bulk amorphous alloy (Fe40Ni40P14B6)96Ga4 in supercooled liquid region

Transmission electron microscopy is used to resolve the crystallization of the bulk amorphous alloy (Fe40Ni40P14B6)96Ga4. Nanocrystallization is observed in supercooled liquid region for bulk amorphous alloy (Fe40Ni40P14B6)96Ga4. The annealing temperature varies from 680 K to 730 K where supercooled liquid region exists. The annealing time is 60 min for all samples. Crystallization does not occur until the annealing temperature exceeds 680 K. Crystal unions consisting of nanocrystals start to precipitate in amorphous base when the annealing temperature arrives at 690 K. The average diameter of crystal unions is about 150-250 nm. Crystal unions already knock together when the annealing temperature comes to 700 K. When the annealing temperature reaches 710 K, another microstructure is formed, consisting of the uniform nanocrystals with a grain size of about 8 nm. When the annealing temperature is increased to 730 K, the nanocrystals grow up into the bacilliform crystals with the average diameter of about 30 nm.