Thermal equilibrium defects in iron-based alloys

Abstract

The Mossbauer spectra of 57Fe were measured for the thermal equilibrium b.c.c. Pe0.947V0.053 and Fe0.956Co0.044 solid solutions being at temperature ranging from 300 to 1,000 K. The obtained data were analysed in terms of concentration of unoccupied sites in the 14-site surroundings of an 57Fe Mossbauer probe in a b.c.c. sample. It turned out that the probe detects unoccupied sites in its neighbourhood when the temperature of the material studied does not exceed about 900 K. This result suggests that the Mossbauer spectroscopy “sees” the pre-vacancy effect revealed by the positron annihilation spectroscopy in the early 1960s.