An Enthalpy of Solution of Cobalt and Nickel in Iron Studied with⁵⁷Fe Mössbauer Spectroscopy

Abstract

The room temperature Mssbauer spectra of 57 Fe were measured for iron-based solid solutions Fe 1-x Co x and Fe 1-x Ni x with x in the range 0.01 x 0.05. The obtained data were analysed in terms of the binding energy E b between two Co or Ni atoms in the studied materials using the extended Hrynkiewicz-Krlas idea. It was found that the energy is positive or the non-iron atoms interact repulsively. The extrapolated value of E b for x = 0 was used for computation of the enthalpy of solution of cobalt and nickel in iron. The results were compared with our previous Mssbauer spectroscopy findings, the values resulting from the Miedema's model of alloys and the data derived from the enthalpy of formation of the Fe-Co and Fe-Ni systems, obtained with calorimetric methods. The comparison shows that the present results are in a qualitative agreement with the Miedema's model predictions and calorimetric measurements but they are at variance with the previous Mssbauer spectroscopy findings.