Dynamic Recrystallization and Phase Precipitation Behavior in Ti‐55531 Alloy During Through‐Transus Forging

The dynamic recrystallization (DRX) and α‐phase precipitation behavior of the Ti‐55531 titanium alloy during through‐transus forging are systematically investigated. The results indicate that flow characteristics are closely related to recrystallization mechanism, and the influence of cooling rate on the flow characteristics of the stress–strain curves is more significant compared to that of final deformation temperature. When the Ti‐55531 alloy is cooled from 870 °C to 800 °C at 5 °C min −1 , continuous DRX and discontinuous DRX (DDRX) are the main deformation mechanism of the β phase. As the final deformation temperature decreases to 700 °C, the extent of DDRX is reduced. Under these conditions, a novel DRX mechanism named geometric‐rotation DRX occurs, accompanying by large deformation‐driven subgrain rotation. Furthermore, an increase in the cooling rate from 5 to 60 °C min −1 favors the initiation and dominance of geometric DRX. Additionally, the precipitation of α phase increases with decreasing final deformation temperature and cooling rate. These fine α particles with an average size of 1.12 μm, effectively suppress DRX by enhancing dislocation pinning and restricting grain boundary migration. Moreover, the α phase precipitating adjacent to recrystallized β grains results in deviations from the Burgers orientation relationship, thereby further retarding the recrystallization of the β matrix.