High-temperature Mossbauer spectra of nanocrystalline Fe73.5Cu1Nb3B7Si
15.5 were measured in the temperature range from room temperature to 5
00 degrees C. The external field dependence of the crystalline compone
nt was studied at 350 degrees C. No indications of small particle effe
cts were detected. The amorphous component in the ribbon contributes t
o the exchange interaction of the system below its magnetic ordering t
emperature.