Thermodynamic assessment of arsenic in iron and nickel alloys

The activities of the different components in Fe–As, Ni–As and Fe–Ni–As systems were calculated using a combination of the molecular interaction volume model, Miedema’s semi-empirical enthalpy model and the Tanaka equation. The calculated values were in good agreement with previously reported experimental measurements. The Henrian coefficients of arsenic at infinite dilution in iron and nickel-based solutions were calculated and their dependence on temperature was represented by the following equations: The interaction parameters were also calculated and presented as functions of temperature: