NEUTRON-IRRADIATION EFFECT ON AMORPHOUS AND NANOCRYSTALLINE FEZRB(CU)AT LOW-TEMPERATURE

The microstructure and magnetic properties of the amorphous and nanocr ystalline Fe(87.5-X)Zr(6.5)sB(6)Cu(X) (s = 0, 1) were studied using Mo ssbauer spectroscopy at liquid nitrogen temperature. Low temperature m easurement of Mossbauer spectra enables a good resolution of the compo nents the sample consist of. Under these conditions effect of neutron irradiation is easily studied through changes of average value of hype rfine magnetic field, hyperfine field distribution and orientation of net magnetic moment. As-cast samples reveal the existence of inequival ent sites of Fe corresponding to broad six line spectra at 77 K. Chang es in the orientation of net magnetic moment were observed after neutr on irradiation. Considerable changes were observed in the amorphous re st of the nanocrystalline samples. After the neutron irradiation low a nd high field components are well separated. Field resolution increase s towards the higher stage of crystallization. Deviations in a magneti c structure are supposed to be a consequence of changes in a short ran ge order due to neutron irradiation. (C) 1997 Elsevier Science S.A.