Structural and magnetic properties of the intergranular amorphous phase inFeNbB nanocrystalline alloys

Static and hyperfine magnetic characteristics of an Fes(0.85)Nb(7)B(12.5) n anocrystalline alloy consisting of bcc-Fe nanograins embedded in residual a morphous matrix are compared to those of a hypothetical composite alloy whi ch consists of bulk bcc-Fe and an amorphous alloy in the as-quenched state. The chemical composition of the latter and the proportions of these two co nstituents were estimated from the mass balance considerations according to the experimentally determined crystalline fraction. The two-phase descript ion of such a hypothetical composite alloy is a posteriori confirmed by the low temperature magnetic characteristics. The degree of compositional hete rogeneity of the residual amorphous matrix in the nanocrystalline sample is found to be considerably higher as compared to that of its bulk single-pha se as-quenched counterpart. The differences of magnetic behaviour versus te mperature allow some aspects of the chemical and structural nature of the i ntergranular amorphous phase in nanocrystalline alloy to be discussed.