Recrystallization nucleation in V-4Cr-4Ti alloy

V-4Cr-4Ti alloy has been taken into account as one of the most promising candidate structural materials for future fusion reactors. In the present study, the recrystallization nucleation of the alloy is investigated by optical and electron microscopies and hardness tests. The results indicate that the nucleation preferentially occurs at original boundaries of deformed grains for static and dynamic recrystallization in spite of less total boundary area due to coarse initial grains in the alloy. Meanwhile, heavy deformation and lath-like pre-precipitates promote recrystallization nucleation within deformed grains, respectively. A deformation-induced dislocation piling up model has been proposed, which can explain for all the phenomena.