Partition Behavior of Alloying Elements in Nickel-Based Alloys and Their Activity Interaction Parameters and Infinite Dilution Activity Coefficients

The partition behavior of alloying elements between the γ’ and γ phases in Nickel-based alloys was investigated by using infinite dilution activity coefficient and activity interaction parameter. The results showed that the preferential partition behavior of elements in the γ’ and γ phases is related to its infinite dilution activity coefficient (\ln \gamma _i^0). When \ln \gamma _i^0 \ll 0, the element i has a strong tendency to partition in the γ’ phase; When \ln \gamma _i^0 approaches to zero, the element i has preferentially partition to the matrix γ phase. In addition, the partition behavior of element i in the γ’ and γ phases is also affected by the third element j in Nickel-based alloys, and this effect can be distinguished by the sign of the second-order activity interaction parameter \rho _i^{ij}.