Thermodynamics of ternary nitrogen austenites

Abstract

The solubility of nitrogen in Fe-Mn-N austenites in equilibrium with N 2-gas at atmospheric pressure has been measured in the temperature range 1173-1450 K and in the Mn-composition range 0-15 at. % Mn. The thermodynamic functions of the dissolved N-atoms have been deduced from the solubility data and compared with those measured for N-austenites containing Ni, Co, and Cr as substitutional solutes. The thermodynamic properties of the f.c.c. ternary solid solutions are in good accord with the cell model for such systems. Elastic and thermal data have been used to predict the properties of the corresponding liquid ternary solutions from the measured data for the solid phase. Good agreement is found with experimental thermodynamic parameters for the liquid solutions at 1873 K. © 1983.