Effect of (Ti+Al)/Nb Value in γ′,γ″ and γ Phase Mixture on Volume Fraction of Phases in IN718 Alloy
An optimized mathematical model was established to calculate the composition and volume fraction of γ′-Ni3Al and γ″-Ni3Nb phases in IN718 alloy.The feasibility and accuracy of MPSM to calculate the composition and volume fraction of these two phases were also demonstrated.The composition,volume fraction and elemental partitioning fraction of the two precipitated phases after adjusting (Ti+Al) /Nb value in γ′,γ″ and γ mixture were calculated through the application of MPSM method.The reason why the adjustment could affect the high-temperature stability of modified IN718 alloys was also explained.