Magnetic Softening and Hardening in Metglas® 2605SC at the Onset of Nanocrystallization

Abstract

ABSTRACTMössbauer spectroscopy, coercive field and permeability were used to study the transformations produced by annealing at 375°C as-quenched amorphous ribbons of Metglas® 2605 SC of nominal composition Fe81B13.5Si3.5C2. The coercive field showed a decrease (softening) in the 0-30 min range, followed by an increase (hardening) for annealing times above 30 min. Permeability exhibited the opposite behavior, with a maximum for about 30 min. The Mössbauer magnetic hyperfine spectra showed variations in the intensities ratios, which were related with macroscopic measurements in good agreement with the softening-hardening processes.