Effect of Post-irradiation Annealing on Microstructure Evolution and Hardening in GH3535 Alloy Irradiated by Au Ions

The Au ion-irradiation experiments of GH3535 alloy, a candidate alloy structural material for molten salt reactor, was carried out in this study. Herein, isochronous annealing experiments were conducted from 200 to 850 °C to clarify the evolution behavior of damage defects with increasing temperature. The coarsening of dislocation loops and formation and dissolution of precipitates with increasing annealing temperature were characterized by transmission electron microscopy. Nanoindentation was performed to measure the variation of hardness caused by irradiation. Additionally, the relationship between irradiation hardening and microstructure evolution was established. This study lays a foundation for the evaluation of irradiation damage properties of GH3535 alloy at different annealing temperatures.