Structure and Magnetic Properties οf Fe(Mn)-Si-B-Nb-Cu Alloys

According to high energy X-ray diffraction measurements no significant changes were observed in a short range atomic order of amorphous ribbons $Fe_{73.5-x}Mn_xCu_1Nb_3Si_{13.5}B_9$ (x=1 up to 15 at.%). Thermal stability of the as-prepared alloys was investigated by differential scanning calorimetry and by in situ X-ray diffraction measurements. The two-step crystallization process was revealed, crystallization temperatures $T_{x1}$ and $T_{x2}$ were influenced by Mn content (thermal separation between $T_{x1}$ and $T_{x2}$ completely vanished for x=9). Nanocrystalline state of annealed samples was confirmed by electron transmission microscopy. The influence of Mn substitution on magnetic properties was confirmed by thermomagnetic measurements.