Isothermal structural relaxation of Fe40Ni40B20 metallic glass in the relaxation times spectrum model

The structural relaxation of amorphous as-quenched Fe40Ni40B20 sample was investigated during isothermal annealing at temperatures close to 400 °C by: (i) the residual electrical resistance measured at liquid N2 temperature; (ii) the in-situ electrical resistance; and (iii) the length change. Experimental curves have been analyzed in the frame of the model of relaxation times spectrum using two independent methods for calculation of the spectrum. Apart from some quantitative differences within the specimens cut from different positions in the ribbon, the spectrum of relaxation times N(ln τ) is characterized by the three relatively sharp peaks with the characteristic relaxation times of about 75, 710 and 7000 s, respectively.