High temperature thermodynamic properties of iron-nickel alloys

A correlation is presented for the thermodynamic properties of alloys of iron and nickel at high temperatures. It covers both solid and liquid phases and is in good agreement with the available experimental information. The correlation is based on the assumption that the solutions consist of a mixture of chemical species in a state of thermodynamic equilibrium. The three-suffix Margules equations with zero ternary interactions and the regular solution assumption are used to describe the activity coefficients of the (assumed) species. The correlation is applicable over the full range of compositions, and is recommended for use at temperatures higher than 800 K. Values calculated for properties of interest are included.