• The solidified Alloy 625 Plus ingot exhibits a typical dendritic microstructure with significant segregation of Ti, Nb, and Mo, leading to precipitate formation in interdendritic regions.
• Homogenization effectively reduces element segregation; diffusion constants (D0) and activation energies (Q) for Ti, Nb, and Mo were quantified, enabling predictive diffusion equations.
• A homogenization treatment at 1220 °C for 8 h yields low deformation resistance, high recrystallization degree, and optimal deformation coordination, making it a rational single-stage process.
• The study provides a scientific basis for optimizing homogenization and hot working of Alloy 625 Plus, enhancing its mechanical properties and corrosion resistance for demanding energy and aerospace applications.