Improved hot workability of Cu-3.18wt%Ti alloy via cooperative control of dynamic recrystallization and precipitation

Abstract

The poor hot workability of Cu-Ti alloys has become a bottleneck restricting the further improvement of properties and applications. In this work, the coupling effects of grain structure, precipitates and solid solubility on the hot deformation behaviors of Cu-3.18wt%Ti alloy were deeply studied. Our results show that based on the obtained constitutive equation and thermal activation energies, the corresponding hot workability maps of alloy can be established and used to guide the designation of hot working process. The complex interactions that occur between dislocation and precipitates lead to the differences in dynamic recrystallization (DRX) and precipitation for the changed strain rates and temperatures. The deformability can be improved by coupling control of DRX and dynamic precipitation. The corresponding mechanisms of hot deformation and microstructural evolution of grain structure, precipitates and solid solubility of Ti in the matrix during the hot deformation has been put forward. Our results provide fundamental insight into the DRX, precipitation and coordinated deformation of Cu-Ti alloys with poor deformability, as a function of hot strain.