MÖSSBAUER AND ELECTRICAL STUDIES ON GLASSY ALLOY Fe72Co3Si15B10

Abstract

Metallic glass Fe 72 Co 3 Si 15 B 10 has been investigated using Mossbauer spectroscopy, electrical resistivity and thermoelectric power techniques. The saturation hyperfine magnetic field H eff (0), Curie temperature, T c and crystallization temperature, T x for the sample are found to be 265 ± 5 kOe, 725 ± 5 K and 810 ± 5 K, respectively, by the Mossbauer spectroscopy. Reduced hyperfine magnetic fields vs. reduced temperatures show a similar departure from the Brillouin curve as observed for other iron-rich metallic glasses and can be fitted to the Handrich's model with some modification. Distribution of hyperfine magnetic fields has been evaluated at room temperature which consists of a major single peak centred around the magnetic field close to the measured value of average hyperfine magnetic field H eff . Electrical resistivity data show that the crystallization takes place in two-step process with primary crystallization setting in at 815 K. Absolute thermoelectric power S of the sample is found to be negative through out the temperature region 80 K — 800 K and shows a parabolic behaviour with a minimum around 310 K with S= −5.6 μV/K Value of S falls steeply on crystallization.