An AFM investigation of the mesostructure of Fe-based nanocrystalline ribbon

The mesostructure at the cross section of the Fe-based nanocrystalline (Fe73.5Cu1Nb3Si13.5B9) ribbon was observed with atomic force microscopy (AFM). An apparent mesostructural difference was found between the sticking roller face area (SRFA) and the free face area (FFA) of the ribbon crystallized after annealing. In SRFA there is a pre-ponderance of rough grain gathering in longitudinal ar-rangement, while in FFA a fine grain gathering arranged transversely dominates. This phenomenon could be due to the different residual stress remained in the different areas of the amorphous ribbon resulting from the single-roller quenching technique.