Recrystallization and grain growth behavior of variously deformed CoCrFeMnNi high-entropy alloys: microstructure characterization and modeling

The recrystallization and grain growth behavior of CoCrFeMnNi high-entropy alloys (HEAs) with different plastic deformations were studied. Differential scanning calorimetry (DSC) tests were novelly adopted to characterize the recrystallization process. Experimental results suggest that pre-deformation has great promotion on the recrystallization rate and degree. The recrystallized grain size decreases with increasing deformation due to increased potential nucleation sites. Severe deformation and low annealing temperature are helpful to refine annealed grains. A static recrystallization model for variously deformed HEAs was developed, in which the recrystallization rate was expressed as a function of strain and annealing temperature. An improved grain growth model was established, which takes the recrystallization process into consideration and declares that the annealed grain size decreases first and then increases. The recrystallization fraction and the annealed grain size of the HEAs with different deformations annealed at different temperatures can be predicted.