STRUCTURE TRANSFORMATIONS IN AMORPHOUS FE, CO, AND PD BASED ALLOYS DURING CRYSTALLIZATION TO THE NANOCRYSTALLINE STATE

Amorphous Fe73.5Cu1Nb3Si13.5B9, Fe5Co70Si15B10 and Pd81Cu7Si12 alloys, produced by superfast quenching from the melt followed by fast hearin g to 723-923 K and soaking for 10s in vacuum were investigated. The cr ystallization of an amorphous Fe73Ni0.5Cu1Nb3Si13.5B9 alloy was determ ined by methods of transmission electron microscopy (in situ). The Fe7 3.5Cu1Nb3Si13.5B9 alloy annealed at 923 K for 10 s produces a grain si ze of 6 nm, with phases alpha-FeSi13 at.%, (FeNb)(2)B, and (FeNb)B. An Fe5Co70Si15B10 alloy annealed at 923 K for 10 s produces a grain size of 25 nm, with phases - alpha-Fe, alpha-Co, beta-Co, Fe3Si, Co2Si, an d (FeCo)(2)B. A Pd81Cu7Si12 alloy annealed at 823 K for 10 s produces a grain size of 25 nm, with phases - Pd, Pd-Cu(gamma), Pd5Si, i-PdxSi. (C) 1997 Acta Metallurgica Inc.