Abstract
The segregation process is described in terms of thermodynamic equations that use concepts of excess partial molar free energies and activity coefficients. Using such generalized equations, simplified equations are developed that can be used to check the segregation behavior in terms of thermodynamic quantities that are generally available in the literature. These simplified equations can be used to represent segregation semiquantitatively in many situations, including those where the elements form highly stable chemical compounds, such as sulfides, borides, and phosphides. The validity of our equations is checked by comparing the calculated segregation values with those observed on the surface of Ni, Cr, Al, Y, and NiCrAl(Y) alloys containing small concentrations of sulfur.
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Luthra, K.L., Briant, C.L. Thermodynamics of segregation in alloys. Metall Trans A 19, 2091–2098 (1988). https://doi.org/10.1007/BF02645211
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DOI: https://doi.org/10.1007/BF02645211