ROLE OF ALUMINUM IN STRUCTURAL AND MAGNETIC-PROPERTIES OF NANOCRYSTALLINE ALLOY FESIBNBCU

The influence of partial substitution of Fe, Si and B elements by Al ( up to 9%) is analyzed for a nanocrystalline FeSiBNbCu alloy. Structura l studies show that the increment of Al deteriorates the glass forming ability of the material. Coercivity in amorphous as-quenched samples becomes lower as the Al content increases in two alloy series: while a fter nanocrystallization values as small as about 0.5 A/m are obtained . DSC thermograms show that addition of Al advances the nucleation of the crystalline phase. Also, a particular evolution is noticed when Si is replaced by Al: the exothermic peak characteristic of alpha-(Fe,Si ) phase begins to split into two peaks while increasing the Al content .