Effect of initial microstructure on dynamic recrystallization behavior during creep deformation of a modified Nimonic 80A superalloy

Solution treatment temperature in Alloy 80A variants governed microstructural evolution through carbide dissolution and recrystallization. Elevated temperatures yielded coarse, homogeneous grains, whereas lower temperatures induced bimodal structures via PSN and pinning. The bimodal microstructure facilitated dynamic recrystallization and grain boundary sliding during creep, thereby accelerating damage and diminishing creep life. • Initial grain structure significantly influences dynamic recrystallization kinetics during creep. • Bimodal microstructure from lower-temperature treatment promotes early DRX and thermal softening during creep. • High-temperature solution treatment dissolves carbides, suppresses DRX. • Suppression of DRX in coarse structures leads to improved creep resistance.