Saturation magnetization and amorphous Curie point changes during the early stage of amorphous-nanocrystalline transformation of a FINEMET-type alloy

Saturation magnetization and thermomagnetic curves were determined on FINEM ET-type glassy precursors after different heat treatments below the nanocry stallization temperature. Saturation magnetization (M-s) shows a maximum at the early stage of nanocrystallization, then it drops to below the M-s cha racteristic for the as-quenched state. Curie temperature of the amorphous p hase (T-c(am)) increases continuously due to structural relaxation up to th e beginning of nanocrystallization. The results are interpreted on the basi s of irreversible structural relaxation as well as Si redistribution betwee n the Fe(Si) nanograins and the intergranular amorphous shell. (C) 2000 Els evier Science B.V. All rights reserved.