MICROSTRUCTURE AND HYPERFINE INTERACTIONS OF THE FE73.5NB4.5CR5CUB16 NANOCRYSTALLINE ALLOYS - MOSSBAUER-EFFECT TEMPERATURE-MEASUREMENTS

Mossbauer spectrometry, magnetization measurements and differential sc anning calorimetry were used to investigate the microstructure and hyp erfine interactions in the Fe73.5Nb4.5Cr5CuB16 nanocrystalline alloy o btained by heat treatment of the original amorphous precursor at the t emperature of 550 degrees C for 1 hour. Fe-57 transmission Mossbauer s pectra were taken in the temperature range 5-475 K without and with ex ternal magnetic field oriented parallel (H-ext approximate to 0.05 T) and perpendicular (H-ext approximate to 4 T) to the ribbon-shaped samp le. The as-quenched state of the alloy was also investigated. The Moss bauer effect measurements confirmed the presence of alpha-Fe phase upo n nanocrystallization. Magnetic states of Fe atoms in amorphous and in terfacial regions are studied via distributions of hyperfine fields.