NMR studies of electron and gamma irradiated CoFeNiSiBC amorphous alloy

NMR spectra were obtained by spin-echo technique in the frequency interval of 40--I40 MHz at the temperature 4.2 K. Samples of the investigated amorphous ribbon of the composition Co--12.6%Ni-6.1%Fe-4.6%B-6.3%Si-0.018%C were prepared by rapid quenching from the melt. After electron and gamma irradiation the NMR spectrum main lines widths are decreased and the frequencies of the main peaks are shifted. The observed changes of the spectrum can be interpreted as irradiation-induced changes in Co2B and Co3B short-range order and as destruction of crystal nuclei. These findings are confirmed by increase of the crystallization temperature controlled by thermomagnetic analysis.