Mössbauer study of FeCoNbBCu hitperm-type alloys

FeCoNbBCu alloys have been studied by Mössbauer spectrometry. A high contribution of the interfacial region in the nanocrystalline samples to the hyperfine field distribution is detected. The possible presence of B in the nanocrystalline grains is also discussed. Low values of the hyperfine field with respect to the disordered α-FeCo phase suggest the presence of the ordered α′α′-FeCo phase. Recrystallization phenomena at the second crystallization stage are confirmed.